diff --git a/pkg/dart2native/lib/generate.dart b/pkg/dart2native/lib/generate.dart
index 5304ab7dec6..0fb6d690d41 100644
--- a/pkg/dart2native/lib/generate.dart
+++ b/pkg/dart2native/lib/generate.dart
@@ -72,7 +72,6 @@ Future<void> generateNative({
   String? resourcesFile,
   String enableExperiment = '',
   bool enableAsserts = false,
-  bool soundNullSafety = true,
   bool verbose = false,
   String verbosity = 'all',
   List<String> extraOptions = const [],
@@ -122,7 +121,6 @@ Future<void> generateNative({
       extraGenKernelOptions: [
         '--invocation-modes=compile',
         '--verbosity=$verbosity',
-        '--${soundNullSafety ? '' : 'no-'}sound-null-safety',
       ],
       resourcesFile: resourcesFile,
       aot: true,
@@ -150,7 +148,6 @@ Future<void> generateNative({
         extraGenKernelOptions: [
           '--invocation-modes=compile',
           '--verbosity=$verbosity',
-          '--${soundNullSafety ? '' : 'no-'}sound-null-safety',
         ],
         nativeAssets: nativeAssets,
         aot: true,
@@ -172,12 +169,8 @@ Future<void> generateNative({
       );
     }
 
-    final extraAotOptions = <String>[
-      if (!soundNullSafety) '--no-sound-null-safety',
-      ...extraOptions
-    ];
     if (verbose) {
-      print('Generating AOT snapshot. $genSnapshot $extraAotOptions');
+      print('Generating AOT snapshot. $genSnapshot $extraOptions');
     }
     final snapshotFile =
         kind == Kind.aot ? outputPath : path.join(tempDir.path, 'snapshot.aot');
@@ -186,7 +179,7 @@ Future<void> generateNative({
       snapshotFile,
       debugPath,
       enableAsserts,
-      extraAotOptions,
+      extraOptions,
     );
 
     if (verbose || snapshotResult.exitCode != 0) {
@@ -260,7 +253,6 @@ Future<void> generateKernel({
   //   What are the implications of using a product mode kernel
   //   in a non-product runtime?
   bool product = true,
-  bool soundNullSafety = true,
   bool verbose = false,
   String? nativeAssets,
   String? resourcesFile,
@@ -282,7 +274,6 @@ Future<void> generateKernel({
     extraGenKernelOptions: [
       '--invocation-modes=compile',
       '--verbosity=$verbosity',
-      '--${soundNullSafety ? '' : 'no-'}sound-null-safety',
     ],
     nativeAssets: nativeAssets,
     resourcesFile: resourcesFile,
diff --git a/pkg/dartdev/lib/src/commands/compile.dart b/pkg/dartdev/lib/src/commands/compile.dart
index c8564ae7913..6b403e048c8 100644
--- a/pkg/dartdev/lib/src/commands/compile.dart
+++ b/pkg/dartdev/lib/src/commands/compile.dart
@@ -235,7 +235,6 @@ class CompileKernelSnapshotCommand extends CompileSubcommandCommand {
         enableExperiment: args.enabledExperiments.join(','),
         linkPlatform: args.flag('link-platform'),
         embedSources: args.flag('embed-sources'),
-        soundNullSafety: args.flag('sound-null-safety'),
         verbose: verbose,
         verbosity: args.option('verbosity')!,
       );
@@ -518,7 +517,6 @@ Remove debugging information from the output and save it separately to the speci
         packages: args.option('packages'),
         enableExperiment: args.enabledExperiments.join(','),
         enableAsserts: args.flag('enable-asserts'),
-        soundNullSafety: args.flag('sound-null-safety'),
         debugFile: args.option('save-debugging-info'),
         verbose: verbose,
         verbosity: args.option('verbosity')!,
diff --git a/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally.dart.weak.transformed.expect b/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally.dart.weak.transformed.expect
index d99c27234a5..bd2d823ad50 100644
--- a/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally.dart.weak.transformed.expect
@@ -20,7 +20,7 @@ static const field core::String var12 = #C5;
 static const field core::int var13 = #C2;
 static method fn(dynamic error) → core::int {
   try {
-    throw error as{TypeError,Unchecked} core::Object;
+    throw let dynamic #t1 = error in #t1 == null ?{core::Object} #t1 as{TypeError} core::Object : #t1{core::Object};
   }
   on core::String catch(no-exception-var) {
     return 0;
@@ -31,7 +31,7 @@ static method fn(dynamic error) → core::int {
 }
 static method fn1(dynamic error) → core::int {
   try {
-    throw error as{TypeError,Unchecked} core::Object;
+    throw let dynamic #t2 = error in #t2 == null ?{core::Object} #t2 as{TypeError} core::Object : #t2{core::Object};
   }
   on core::int catch(final core::int e) {
     return e;
@@ -44,7 +44,7 @@ static method finallyReturn(dynamic error) → core::int {
   try
     try {
       if(!(error =={core::Object::==}{(core::Object) → core::bool} 1))
-        throw error as{TypeError,Unchecked} core::Object;
+        throw let dynamic #t3 = error in #t3 == null ?{core::Object} #t3 as{TypeError} core::Object : #t3{core::Object};
     }
     on core::int catch(final core::int e) {
       return e;
diff --git a/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart.weak.transformed.expect b/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart.weak.transformed.expect
index 82893accf97..8133640c296 100644
--- a/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart.weak.transformed.expect
@@ -62,7 +62,7 @@ static method finallyThrow(core::int x) → core::int {
 }
 static method unhandledThrow(dynamic x) → core::int {
   try {
-    throw x as{TypeError,Unchecked} core::Object;
+    throw let dynamic #t1 = x in #t1 == null ?{core::Object} #t1 as{TypeError} core::Object : #t1{core::Object};
   }
   on core::String catch(final core::String e) {
     throw e;
diff --git a/pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart.weak.transformed.expect b/pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart.weak.transformed.expect
index aa4842ffaca..12eb3c53c4c 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart.weak.transformed.expect
@@ -40,20 +40,20 @@ static method test() → dynamic {
   self::Class c = new self::Class::•();
   (core::int, core::int) → core::int f = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:16:30: Error: A value of type 'int Function(int, int)?' can't be assigned to a variable of type 'int Function(int, int)' because 'int Function(int, int)?' is nullable and 'int Function(int, int)' isn't.
   int Function(int, int) f = alias;
-                             ^" in (let final <T extends core::Object? = dynamic>(T%, core::int) →? T% #t1 = self::alias in #t1 == null ?{(core::int, core::int) →? core::int} null : #t1{<T extends core::Object? = dynamic>(T%, core::int) → T%}<core::int>) as{TypeError,Unchecked} (core::int, core::int) → core::int;
+                             ^" in let (core::int, core::int) →? core::int #t1 = let final <T extends core::Object? = dynamic>(T%, core::int) →? T% #t2 = self::alias in #t2 == null ?{(core::int, core::int) →? core::int} null : #t2{<T extends core::Object? = dynamic>(T%, core::int) → T%}<core::int> in #t1 == null ?{(core::int, core::int) → core::int} #t1 as{TypeError} (core::int, core::int) → core::int : #t1{(core::int, core::int) → core::int};
   (core::int, core::int?) →? core::int g;
   g = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:18:7: Error: A value of type 'int Function(int, int)?' can't be assigned to a variable of type 'int Function(int, int?)?' because 'int?' is nullable and 'int' isn't.
   g = alias;
-      ^" in (let final <T extends core::Object? = dynamic>(T%, core::int) →? T% #t2 = self::alias in #t2 == null ?{(core::int, core::int) →? core::int} null : #t2{<T extends core::Object? = dynamic>(T%, core::int) → T%}<core::int>) as{TypeError,Unchecked} (core::int, core::int?) →? core::int;
+      ^" in (let final <T extends core::Object? = dynamic>(T%, core::int) →? T% #t3 = self::alias in #t3 == null ?{(core::int, core::int) →? core::int} null : #t3{<T extends core::Object? = dynamic>(T%, core::int) → T%}<core::int>) as{TypeError} (core::int, core::int?) →? core::int;
   (core::int, core::int?) → core::int h = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:19:27: Error: A value of type 'int Function(int, int)' can't be assigned to a variable of type 'int Function(int, int?)' because 'int?' is nullable and 'int' isn't.
   int Function(int, int?) h = c;
-                          ^" in ((let final self::Class #t3 = c in #t3 == null ?{<T extends core::Object? = dynamic>(T%, core::int) → T%} null : #t3.{self::Class::call}{<T extends core::Object? = dynamic>(T%, core::int) → T%})<core::int>) as{TypeError,Unchecked} (core::int, core::int?) → core::int;
+                          ^" in ((let final self::Class #t4 = c in #t4 == null ?{<T extends core::Object? = dynamic>(T%, core::int) → T%} null : #t4.{self::Class::call}{<T extends core::Object? = dynamic>(T%, core::int) → T%})<core::int>) as{TypeError} (core::int, core::int?) → core::int;
   g = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:20:3: Error: A value of type 'int Function(int, int)' can't be assigned to a variable of type 'int Function(int, int?)?' because 'int?' is nullable and 'int' isn't.
   g = c;
-  ^" in ((let final self::Class #t4 = c in #t4 == null ?{<T extends core::Object? = dynamic>(T%, core::int) → T%} null : #t4.{self::Class::call}{<T extends core::Object? = dynamic>(T%, core::int) → T%})<core::int>) as{TypeError,Unchecked} (core::int, core::int?) →? core::int;
+  ^" in ((let final self::Class #t5 = c in #t5 == null ?{<T extends core::Object? = dynamic>(T%, core::int) → T%} null : #t5.{self::Class::call}{<T extends core::Object? = dynamic>(T%, core::int) → T%})<core::int>) as{TypeError} (core::int, core::int?) →? core::int;
   self::method(invalid-expression "pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:21:10: Error: The argument type 'int Function(int, int)?' can't be assigned to the parameter type 'int Function(int, int?)' because 'int?' is nullable and 'int' isn't.
   method(alias);
-         ^" in (let final <T extends core::Object? = dynamic>(T%, core::int) →? T% #t5 = self::alias in #t5 == null ?{(core::int, core::int) →? core::int} null : #t5{<T extends core::Object? = dynamic>(T%, core::int) → T%}<core::int>) as{TypeError,Unchecked} (core::int, core::int?) → core::int);
+         ^" in (let final <T extends core::Object? = dynamic>(T%, core::int) →? T% #t6 = self::alias in #t6 == null ?{(core::int, core::int) →? core::int} null : #t6{<T extends core::Object? = dynamic>(T%, core::int) → T%}<core::int>) as{TypeError} (core::int, core::int?) → core::int);
 }
 static method main() → dynamic {}
 
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/invalid_redirect.dart.weak.transformed.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/invalid_redirect.dart.weak.transformed.expect
index 24ec5885ddb..fe694aad4be 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/invalid_redirect.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/invalid_redirect.dart.weak.transformed.expect
@@ -84,7 +84,7 @@ class LinkFactory extends core::Object {
     return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/invalid_redirect.dart:14:12: Error: The value 'null' can't be returned from a function with return type 'LinkFactory' because 'LinkFactory' is not nullable.
  - 'LinkFactory' is from 'pkg/front_end/testcases/constructor_tearoffs/lowering/invalid_redirect.dart'.
     return null;
-           ^" in null as{TypeError,Unchecked} self::LinkFactory;
+           ^" in let Null #t1 = null in #t1 == null ?{self::LinkFactory} #t1 as{TypeError} self::LinkFactory : #t1{self::LinkFactory};
   }
   static method _#create#tearOff() → self::LinkFactory
     return self::LinkFactory::create();
diff --git a/pkg/front_end/testcases/extension_types/assign_interface_type.dart.weak.transformed.expect b/pkg/front_end/testcases/extension_types/assign_interface_type.dart.weak.transformed.expect
index 60ad2e84e59..151a31bd6e6 100644
--- a/pkg/front_end/testcases/extension_types/assign_interface_type.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/extension_types/assign_interface_type.dart.weak.transformed.expect
@@ -388,22 +388,22 @@ static method test<T1 extends core::Object? = dynamic, T2 extends self::A, T3 ex
   o = invalid-expression "pkg/front_end/testcases/extension_types/assign_interface_type.dart:39:7: Error: A value of type 'C' can't be assigned to a variable of type 'Object' because 'C' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   o = c; // Error
-      ^" in c as{TypeError,Unchecked} core::Object;
+      ^" in let self::C% /* erasure=core::Object?, declared=! */ #t1 = c in #t1 == null ?{core::Object} #t1 as{TypeError} core::Object : #t1{core::Object};
   o = d;
   o = invalid-expression "pkg/front_end/testcases/extension_types/assign_interface_type.dart:41:7: Error: A value of type 'D2' can't be assigned to a variable of type 'Object' because 'D2' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   o = d2; // Error
-      ^" in d2 as{TypeError,Unchecked} core::Object;
+      ^" in let self::D2% /* erasure=core::Object, declared=! */ #t2 = d2 in #t2 == null ?{core::Object} #t2 as{TypeError} core::Object : #t2{core::Object};
   o = e;
   o = f;
   o = invalid-expression "pkg/front_end/testcases/extension_types/assign_interface_type.dart:44:7: Error: A value of type 'G<T1>' can't be assigned to a variable of type 'Object' because 'G<T1>' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   o = g1; // Error
-      ^" in g1 as{TypeError,Unchecked} core::Object;
+      ^" in let self::G<self::test::T1%>% /* erasure=self::test::T1%, declared=! */ #t3 = g1 in #t3 == null ?{core::Object} #t3 as{TypeError} core::Object : #t3{core::Object};
   o = invalid-expression "pkg/front_end/testcases/extension_types/assign_interface_type.dart:45:7: Error: A value of type 'G<T2>' can't be assigned to a variable of type 'Object' because 'G<T2>' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   o = g2; // Error
-      ^" in g2 as{TypeError,Unchecked} core::Object;
+      ^" in let self::G<self::test::T2>% /* erasure=self::test::T2, declared=! */ #t4 = g2 in #t4 == null ?{core::Object} #t4 as{TypeError} core::Object : #t4{core::Object};
   o = g3;
   a = invalid-expression "pkg/front_end/testcases/extension_types/assign_interface_type.dart:48:7: Error: A value of type 'Object' can't be assigned to a variable of type 'A'.
  - 'Object' is from 'dart:core'.
diff --git a/pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart.weak.transformed.expect b/pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart.weak.transformed.expect
index 1465afd6618..73bbda4ce5c 100644
--- a/pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart.weak.transformed.expect
@@ -208,122 +208,122 @@ static method test1(self::E1% /* erasure=core::Object, declared=! */ e1, self::E
   core::Object v1 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:14:15: Error: A value of type 'E1' can't be assigned to a variable of type 'Object' because 'E1' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object v1 = e1; // Error.
-              ^" in e1 as{TypeError,Unchecked} core::Object;
+              ^" in let self::E1% /* erasure=core::Object, declared=! */ #t1 = e1 in #t1 == null ?{core::Object} #t1 as{TypeError} core::Object : #t1{core::Object};
   e1 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:15:8: Error: The value 'null' can't be assigned to a variable of type 'E1' because 'E1' is not nullable.
   e1 = null; // Error.
-       ^" in null as{TypeError,Unchecked} self::E1% /* erasure=core::Object, declared=! */;
+       ^" in let Null #t2 = null in #t2 == null ?{self::E1% /* erasure=core::Object, declared=! */} #t2 as{TypeError} self::E1% /* erasure=core::Object, declared=! */ : #t2{self::E1% /* erasure=core::Object, declared=! */};
   core::Object v2 = e2;
   e2 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:18:8: Error: The value 'null' can't be assigned to a variable of type 'E2' because 'E2' is not nullable.
   e2 = null; // Error.
-       ^" in null as{TypeError,Unchecked} self::E2 /* erasure=core::Object */;
+       ^" in let Null #t3 = null in #t3 == null ?{self::E2 /* erasure=core::Object */} #t3 as{TypeError} self::E2 /* erasure=core::Object */ : #t3{self::E2 /* erasure=core::Object */};
   core::Object v3 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:20:15: Error: A value of type 'E3' can't be assigned to a variable of type 'Object' because 'E3' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object v3 = e3; // Error.
-              ^" in e3 as{TypeError,Unchecked} core::Object;
+              ^" in let self::E3% /* erasure=core::Object, declared=! */ #t4 = e3 in #t4 == null ?{core::Object} #t4 as{TypeError} core::Object : #t4{core::Object};
   e3 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:21:8: Error: The value 'null' can't be assigned to a variable of type 'E3' because 'E3' is not nullable.
   e3 = null; // Error.
-       ^" in null as{TypeError,Unchecked} self::E3% /* erasure=core::Object, declared=! */;
+       ^" in let Null #t5 = null in #t5 == null ?{self::E3% /* erasure=core::Object, declared=! */} #t5 as{TypeError} self::E3% /* erasure=core::Object, declared=! */ : #t5{self::E3% /* erasure=core::Object, declared=! */};
   core::Object v4 = e4;
   e4 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:24:8: Error: The value 'null' can't be assigned to a variable of type 'E4' because 'E4' is not nullable.
   e4 = null; // Error.
-       ^" in null as{TypeError,Unchecked} self::E4 /* erasure=core::Object */;
+       ^" in let Null #t6 = null in #t6 == null ?{self::E4 /* erasure=core::Object */} #t6 as{TypeError} self::E4 /* erasure=core::Object */ : #t6{self::E4 /* erasure=core::Object */};
   core::Object v5 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:26:15: Error: A value of type 'E5<dynamic>' can't be assigned to a variable of type 'Object' because 'E5<dynamic>' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object v5 = e5; // Error.
-              ^" in e5 as{TypeError,Unchecked} core::Object;
+              ^" in let self::E5<dynamic>% /* erasure=dynamic, declared=! */ #t7 = e5 in #t7 == null ?{core::Object} #t7 as{TypeError} core::Object : #t7{core::Object};
   e5 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:27:8: Error: The value 'null' can't be assigned to a variable of type 'E5<dynamic>' because 'E5<dynamic>' is not nullable.
   e5 = null; // Error.
-       ^" in null as{TypeError,Unchecked} self::E5<dynamic>% /* erasure=dynamic, declared=! */;
+       ^" in let Null #t8 = null in #t8 == null ?{self::E5<dynamic>% /* erasure=dynamic, declared=! */} #t8 as{TypeError} self::E5<dynamic>% /* erasure=dynamic, declared=! */ : #t8{self::E5<dynamic>% /* erasure=dynamic, declared=! */};
   core::Object v6 = e6;
   e6 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:30:8: Error: The value 'null' can't be assigned to a variable of type 'E6<Object>' because 'E6<Object>' is not nullable.
  - 'Object' is from 'dart:core'.
   e6 = null; // Error.
-       ^" in null as{TypeError,Unchecked} self::E6<core::Object> /* erasure=core::Object */;
+       ^" in let Null #t9 = null in #t9 == null ?{self::E6<core::Object> /* erasure=core::Object */} #t9 as{TypeError} self::E6<core::Object> /* erasure=core::Object */ : #t9{self::E6<core::Object> /* erasure=core::Object */};
   core::Object v7 = e7;
   e7 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:33:8: Error: The value 'null' can't be assigned to a variable of type 'E7' because 'E7' is not nullable.
   e7 = null; // Error.
-       ^" in null as{TypeError,Unchecked} self::E7 /* erasure=core::num */;
+       ^" in let Null #t10 = null in #t10 == null ?{self::E7 /* erasure=core::num */} #t10 as{TypeError} self::E7 /* erasure=core::num */ : #t10{self::E7 /* erasure=core::num */};
 }
 static method test2<X1 extends self::E1% /* erasure=core::Object, declared=! */, X2 extends self::E2 /* erasure=core::Object */, X3 extends self::E3% /* erasure=core::Object, declared=! */, X4 extends self::E4 /* erasure=core::Object */, X5 extends self::E5<dynamic>% /* erasure=dynamic, declared=! */, X6 extends self::E6<core::Object> /* erasure=core::Object */, X7 extends self::E7 /* erasure=core::num */>(self::test2::X1% x1, self::test2::X2 x2, self::test2::X3% x3, self::test2::X4 x4, self::test2::X5% x5, self::test2::X6 x6, self::test2::X7 x7) → dynamic {
   core::Object v1 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:38:15: Error: A value of type 'X1' can't be assigned to a variable of type 'Object' because 'X1' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object v1 = x1; // Error.
-              ^" in x1 as{TypeError,Unchecked} core::Object;
+              ^" in let self::test2::X1% #t11 = x1 in #t11 == null ?{core::Object} #t11 as{TypeError} core::Object : #t11{core::Object};
   x1 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:39:8: Error: The value 'null' can't be assigned to a variable of type 'X1' because 'X1' is not nullable.
   x1 = null; // Error.
-       ^" in null as{TypeError,Unchecked} Never;
+       ^" in let Null #t12 = null in #t12 == null ?{Never} #t12 as{TypeError} Never : #t12{Never};
   core::Object v2 = x2;
   x2 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:42:8: Error: The value 'null' can't be assigned to a variable of type 'X2' because 'X2' is not nullable.
   x2 = null; // Error.
-       ^" in null as{TypeError,Unchecked} Never;
+       ^" in let Null #t13 = null in #t13 == null ?{Never} #t13 as{TypeError} Never : #t13{Never};
   core::Object v3 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:44:15: Error: A value of type 'X3' can't be assigned to a variable of type 'Object' because 'X3' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object v3 = x3; // Error.
-              ^" in x3 as{TypeError,Unchecked} core::Object;
+              ^" in let self::test2::X3% #t14 = x3 in #t14 == null ?{core::Object} #t14 as{TypeError} core::Object : #t14{core::Object};
   x3 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:45:8: Error: The value 'null' can't be assigned to a variable of type 'X3' because 'X3' is not nullable.
   x3 = null; // Error.
-       ^" in null as{TypeError,Unchecked} Never;
+       ^" in let Null #t15 = null in #t15 == null ?{Never} #t15 as{TypeError} Never : #t15{Never};
   core::Object v4 = x4;
   x4 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:48:8: Error: The value 'null' can't be assigned to a variable of type 'X4' because 'X4' is not nullable.
   x4 = null; // Error.
-       ^" in null as{TypeError,Unchecked} Never;
+       ^" in let Null #t16 = null in #t16 == null ?{Never} #t16 as{TypeError} Never : #t16{Never};
   core::Object v5 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:50:15: Error: A value of type 'X5' can't be assigned to a variable of type 'Object' because 'X5' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object v5 = x5; // Error.
-              ^" in x5 as{TypeError,Unchecked} core::Object;
+              ^" in let self::test2::X5% #t17 = x5 in #t17 == null ?{core::Object} #t17 as{TypeError} core::Object : #t17{core::Object};
   x5 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:51:8: Error: The value 'null' can't be assigned to a variable of type 'X5' because 'X5' is not nullable.
   x5 = null; // Error.
-       ^" in null as{TypeError,Unchecked} Never;
+       ^" in let Null #t18 = null in #t18 == null ?{Never} #t18 as{TypeError} Never : #t18{Never};
   core::Object v6 = x6;
   x6 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:54:8: Error: The value 'null' can't be assigned to a variable of type 'X6' because 'X6' is not nullable.
   x6 = null; // Error.
-       ^" in null as{TypeError,Unchecked} Never;
+       ^" in let Null #t19 = null in #t19 == null ?{Never} #t19 as{TypeError} Never : #t19{Never};
   core::Object v7 = x7;
   x7 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:57:8: Error: The value 'null' can't be assigned to a variable of type 'X7' because 'X7' is not nullable.
   x7 = null; // Error.
-       ^" in null as{TypeError,Unchecked} Never;
+       ^" in let Null #t20 = null in #t20 == null ?{Never} #t20 as{TypeError} Never : #t20{Never};
 }
 static method test3(self::E1% /* erasure=core::Object, declared=! */ e1, self::E2 /* erasure=core::Object */ e2, self::E3% /* erasure=core::Object, declared=! */ e3, self::E4 /* erasure=core::Object */ e4, self::E5<dynamic>% /* erasure=dynamic, declared=! */ e5, self::E6<core::Object> /* erasure=core::Object */ e6, self::E7 /* erasure=core::num */ e7, core::String s, core::bool b) → dynamic {
   core::Object? v11 = b ?{core::Object?} e1 : s;
   core::Object v12 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:62:16: Error: A value of type 'Object?' can't be assigned to a variable of type 'Object' because 'Object?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object v12 = v11; // Error.
-               ^" in v11 as{TypeError,Unchecked} core::Object;
+               ^" in let core::Object? #t21 = v11 in #t21 == null ?{core::Object} #t21 as{TypeError} core::Object : #t21{core::Object};
   v11 = null;
   core::Object v21 = b ?{core::Object} e2 : s;
   core::Object v22 = v21;
   v21 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:67:9: Error: The value 'null' can't be assigned to a variable of type 'Object' because 'Object' is not nullable.
  - 'Object' is from 'dart:core'.
   v21 = null; // Error.
-        ^" in null as{TypeError,Unchecked} core::Object;
+        ^" in let Null #t22 = null in #t22 == null ?{core::Object} #t22 as{TypeError} core::Object : #t22{core::Object};
   core::Object? v31 = b ?{core::Object?} e3 : s;
   core::Object v32 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:70:16: Error: A value of type 'Object?' can't be assigned to a variable of type 'Object' because 'Object?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object v32 = v31; // Error.
-               ^" in v31 as{TypeError,Unchecked} core::Object;
+               ^" in let core::Object? #t23 = v31 in #t23 == null ?{core::Object} #t23 as{TypeError} core::Object : #t23{core::Object};
   v31 = null;
   core::Object v41 = b ?{core::Object} e4 : s;
   core::Object v42 = v41;
   v41 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:75:9: Error: The value 'null' can't be assigned to a variable of type 'Object' because 'Object' is not nullable.
  - 'Object' is from 'dart:core'.
   v41 = null; // Error.
-        ^" in null as{TypeError,Unchecked} core::Object;
+        ^" in let Null #t24 = null in #t24 == null ?{core::Object} #t24 as{TypeError} core::Object : #t24{core::Object};
   core::Object? v51 = b ?{core::Object?} e5 : s;
   core::Object v52 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:78:16: Error: A value of type 'Object?' can't be assigned to a variable of type 'Object' because 'Object?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object v52 = v51; // Error.
-               ^" in v51 as{TypeError,Unchecked} core::Object;
+               ^" in let core::Object? #t25 = v51 in #t25 == null ?{core::Object} #t25 as{TypeError} core::Object : #t25{core::Object};
   v51 = null;
   core::Object v61 = b ?{core::Object} e6 : s;
   core::Object v62 = v61;
   v61 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:83:9: Error: The value 'null' can't be assigned to a variable of type 'Object' because 'Object' is not nullable.
  - 'Object' is from 'dart:core'.
   v61 = null; // Error.
-        ^" in null as{TypeError,Unchecked} core::Object;
+        ^" in let Null #t26 = null in #t26 == null ?{core::Object} #t26 as{TypeError} core::Object : #t26{core::Object};
   core::Object v71 = b ?{core::Object} e7 : s;
   core::Object v72 = v71;
   v71 = invalid-expression "pkg/front_end/testcases/extension_types/non_nullable_if_implements_object.dart:87:9: Error: The value 'null' can't be assigned to a variable of type 'Object' because 'Object' is not nullable.
  - 'Object' is from 'dart:core'.
   v71 = null; // Error.
-        ^" in null as{TypeError,Unchecked} core::Object;
+        ^" in let Null #t27 = null in #t27 == null ?{core::Object} #t27 as{TypeError} core::Object : #t27{core::Object};
 }
diff --git a/pkg/front_end/testcases/extension_types/nullability.dart.weak.transformed.expect b/pkg/front_end/testcases/extension_types/nullability.dart.weak.transformed.expect
index 93d7c4a146a..58186a7f882 100644
--- a/pkg/front_end/testcases/extension_types/nullability.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/extension_types/nullability.dart.weak.transformed.expect
@@ -219,47 +219,47 @@ static method testNotNonNullable(self::E1<core::num?>% /* erasure=core::num?, de
   core::Object x1numNullable = invalid-expression "pkg/front_end/testcases/extension_types/nullability.dart:13:26: Error: A value of type 'E1<num?>' can't be assigned to a variable of type 'Object' because 'E1<num?>' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object x1numNullable = e1numNullableNNN; // Error.
-                         ^" in e1numNullableNNN as{TypeError,Unchecked} core::Object;
+                         ^" in let self::E1<core::num?>% /* erasure=core::num?, declared=! */ #t1 = e1numNullableNNN in #t1 == null ?{core::Object} #t1 as{TypeError} core::Object : #t1{core::Object};
   core::Object x1double = invalid-expression "pkg/front_end/testcases/extension_types/nullability.dart:14:21: Error: A value of type 'E1<double>' can't be assigned to a variable of type 'Object' because 'E1<double>' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object x1double = e1doubleNNN; // Error.
-                    ^" in e1doubleNNN as{TypeError,Unchecked} core::Object;
+                    ^" in let self::E1<core::double>% /* erasure=core::double, declared=! */ #t2 = e1doubleNNN in #t2 == null ?{core::Object} #t2 as{TypeError} core::Object : #t2{core::Object};
   core::Object x2 = invalid-expression "pkg/front_end/testcases/extension_types/nullability.dart:15:15: Error: A value of type 'E2' can't be assigned to a variable of type 'Object' because 'E2' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object x2 = e2NNN; // Error.
-              ^" in e2NNN as{TypeError,Unchecked} core::Object;
+              ^" in let self::E2% /* erasure=core::Object?, declared=! */ #t3 = e2NNN in #t3 == null ?{core::Object} #t3 as{TypeError} core::Object : #t3{core::Object};
   core::Object x3 = invalid-expression "pkg/front_end/testcases/extension_types/nullability.dart:16:15: Error: A value of type 'E3' can't be assigned to a variable of type 'Object' because 'E3' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object x3 = e3NNN; // Error.
-              ^" in e3NNN as{TypeError,Unchecked} core::Object;
+              ^" in let self::E3% /* erasure=core::String?, declared=! */ #t4 = e3NNN in #t4 == null ?{core::Object} #t4 as{TypeError} core::Object : #t4{core::Object};
   core::Object x4 = invalid-expression "pkg/front_end/testcases/extension_types/nullability.dart:17:15: Error: A value of type 'E4' can't be assigned to a variable of type 'Object' because 'E4' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object x4 = e4NNN; // Error.
-              ^" in e4NNN as{TypeError,Unchecked} core::Object;
+              ^" in let self::E4% /* erasure=core::int, declared=! */ #t5 = e4NNN in #t5 == null ?{core::Object} #t5 as{TypeError} core::Object : #t5{core::Object};
   core::Object x5 = invalid-expression "pkg/front_end/testcases/extension_types/nullability.dart:18:15: Error: A value of type 'E5' can't be assigned to a variable of type 'Object' because 'E5' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object x5 = e5NNN; // Error.
-              ^" in e5NNN as{TypeError,Unchecked} core::Object;
+              ^" in let self::E5% /* erasure=core::Object?, declared=! */ #t6 = e5NNN in #t6 == null ?{core::Object} #t6 as{TypeError} core::Object : #t6{core::Object};
 }
 static method testNotNullable(self::E1<core::num?>% /* erasure=core::num?, declared=! */ e1numNullableNN, self::E1<core::double>% /* erasure=core::double, declared=! */ e1doubleNN, self::E2% /* erasure=core::Object?, declared=! */ e2NN, self::E3% /* erasure=core::String?, declared=! */ e3NN, self::E4% /* erasure=core::int, declared=! */ e4NN, self::E5% /* erasure=core::Object?, declared=! */ e5NN, self::E1<core::num?>? /* erasure=core::num? */ e1numNullableNNNullable, self::E1<core::double>? /* erasure=core::double? */ e1doubleNNNullable, self::E2? /* erasure=core::Object? */ e2NNNullable, self::E3? /* erasure=core::String? */ e3NNNullable, self::E4? /* erasure=core::int? */ e4NNNullable, self::E5? /* erasure=core::Object? */ e5NNNullable) → dynamic {
   e1numNullableNN = invalid-expression "pkg/front_end/testcases/extension_types/nullability.dart:26:21: Error: The value 'null' can't be assigned to a variable of type 'E1<num?>' because 'E1<num?>' is not nullable.
   e1numNullableNN = null; // Error.
-                    ^" in null as{TypeError,Unchecked} self::E1<core::num?>% /* erasure=core::num?, declared=! */;
+                    ^" in let Null #t7 = null in #t7 == null ?{self::E1<core::num?>% /* erasure=core::num?, declared=! */} #t7 as{TypeError} self::E1<core::num?>% /* erasure=core::num?, declared=! */ : #t7{self::E1<core::num?>% /* erasure=core::num?, declared=! */};
   e1doubleNN = invalid-expression "pkg/front_end/testcases/extension_types/nullability.dart:27:16: Error: The value 'null' can't be assigned to a variable of type 'E1<double>' because 'E1<double>' is not nullable.
   e1doubleNN = null; // Error.
-               ^" in null as{TypeError,Unchecked} self::E1<core::double>% /* erasure=core::double, declared=! */;
+               ^" in let Null #t8 = null in #t8 == null ?{self::E1<core::double>% /* erasure=core::double, declared=! */} #t8 as{TypeError} self::E1<core::double>% /* erasure=core::double, declared=! */ : #t8{self::E1<core::double>% /* erasure=core::double, declared=! */};
   e2NN = invalid-expression "pkg/front_end/testcases/extension_types/nullability.dart:28:10: Error: The value 'null' can't be assigned to a variable of type 'E2' because 'E2' is not nullable.
   e2NN = null; // Error.
-         ^" in null as{TypeError,Unchecked} self::E2% /* erasure=core::Object?, declared=! */;
+         ^" in let Null #t9 = null in #t9 == null ?{self::E2% /* erasure=core::Object?, declared=! */} #t9 as{TypeError} self::E2% /* erasure=core::Object?, declared=! */ : #t9{self::E2% /* erasure=core::Object?, declared=! */};
   e3NN = invalid-expression "pkg/front_end/testcases/extension_types/nullability.dart:29:10: Error: The value 'null' can't be assigned to a variable of type 'E3' because 'E3' is not nullable.
   e3NN = null; // Error.
-         ^" in null as{TypeError,Unchecked} self::E3% /* erasure=core::String?, declared=! */;
+         ^" in let Null #t10 = null in #t10 == null ?{self::E3% /* erasure=core::String?, declared=! */} #t10 as{TypeError} self::E3% /* erasure=core::String?, declared=! */ : #t10{self::E3% /* erasure=core::String?, declared=! */};
   e4NN = invalid-expression "pkg/front_end/testcases/extension_types/nullability.dart:30:10: Error: The value 'null' can't be assigned to a variable of type 'E4' because 'E4' is not nullable.
   e4NN = null; // Error.
-         ^" in null as{TypeError,Unchecked} self::E4% /* erasure=core::int, declared=! */;
+         ^" in let Null #t11 = null in #t11 == null ?{self::E4% /* erasure=core::int, declared=! */} #t11 as{TypeError} self::E4% /* erasure=core::int, declared=! */ : #t11{self::E4% /* erasure=core::int, declared=! */};
   e5NN = invalid-expression "pkg/front_end/testcases/extension_types/nullability.dart:31:10: Error: The value 'null' can't be assigned to a variable of type 'E5' because 'E5' is not nullable.
   e5NN = null; // Error.
-         ^" in null as{TypeError,Unchecked} self::E5% /* erasure=core::Object?, declared=! */;
+         ^" in let Null #t12 = null in #t12 == null ?{self::E5% /* erasure=core::Object?, declared=! */} #t12 as{TypeError} self::E5% /* erasure=core::Object?, declared=! */ : #t12{self::E5% /* erasure=core::Object?, declared=! */};
   e1numNullableNNNullable = null;
   e1doubleNNNullable = null;
   e2NNNullable = null;
diff --git a/pkg/front_end/testcases/extension_types/pattern.dart.weak.transformed.expect b/pkg/front_end/testcases/extension_types/pattern.dart.weak.transformed.expect
index d7ea58ea867..afe12a85cfc 100644
--- a/pkg/front_end/testcases/extension_types/pattern.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/extension_types/pattern.dart.weak.transformed.expect
@@ -34,7 +34,7 @@ static method method(self::MyList<core::int> /* erasure=core::List<core::int> */
   hoisted has-declared-initializer core::bool b;
   {
     final synthesized self::MyMap<core::String, core::bool> /* erasure=core::Map<core::String, core::bool> */ #1#0 = map;
-    if(!(#1#0.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (let final core::bool #t2 = b = #1#0.{core::Map::[]}(#C2){(core::Object?) → core::bool?} as{Unchecked} core::bool in true)))
+    if(!(#1#0.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (let final core::bool #t2 = b = let core::bool? #t3 = #1#0.{core::Map::[]}(#C2){(core::Object?) → core::bool?} in #t3 == null ?{core::bool} #t3 as{Unchecked} core::bool : #t3{core::bool} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
   {
@@ -52,7 +52,7 @@ static method method(self::MyList<core::int> /* erasure=core::List<core::int> */
     {
       hoisted core::bool d;
       if(#3#0.{core::Map::containsKey}(#C2){(core::Object?) → core::bool}) {
-        d = #3#0.{core::Map::[]}(#C2){(core::Object?) → core::bool?} as{Unchecked} core::bool;
+        d = let core::bool? #t4 = #3#0.{core::Map::[]}(#C2){(core::Object?) → core::bool?} in #t4 == null ?{core::bool} #t4 as{Unchecked} core::bool : #t4{core::bool};
         {}
       }
     }
@@ -62,12 +62,12 @@ static method method(self::MyList<core::int> /* erasure=core::List<core::int> */
     final synthesized self::MyList<core::int> /* erasure=core::List<core::int> */ #4#0 = list;
     synthesized core::int #4#1;
     synthesized core::bool #4#1#isSet = false;
-    dynamic #t3;
+    dynamic #t5;
     {
       lowered hoisted core::int e#case#0;
       lowered hoisted core::int e#case#1;
-      if((#4#1#isSet ?{core::int} #4#1{core::int} : let final core::bool #t4 = #4#1#isSet = true in #4#1 = #4#0.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C1 && (let final core::int #t5 = e#case#0 = #4#0.{core::List::[]}(0){(core::int) → core::int} in true) && e#case#0.{core::num::>}(5){(core::num) → core::bool} && (let final core::int #t6 = #t3 = e#case#0 in true) || (#4#1#isSet ?{core::int} #4#1{core::int} : let final core::bool #t7 = #4#1#isSet = true in #4#1 = #4#0.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C3 && (let final core::int #t8 = e#case#1 = #4#0.{core::List::[]}(1){(core::int) → core::int} in true) && e#case#1.{core::num::<}(5){(core::num) → core::bool} && (let final core::int #t9 = #t3 = e#case#1 in true)) {
-        core::int e = #t3{core::int};
+      if((#4#1#isSet ?{core::int} #4#1{core::int} : let final core::bool #t6 = #4#1#isSet = true in #4#1 = #4#0.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C1 && (let final core::int #t7 = e#case#0 = #4#0.{core::List::[]}(0){(core::int) → core::int} in true) && e#case#0.{core::num::>}(5){(core::num) → core::bool} && (let final core::int #t8 = #t5 = e#case#0 in true) || (#4#1#isSet ?{core::int} #4#1{core::int} : let final core::bool #t9 = #4#1#isSet = true in #4#1 = #4#0.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C3 && (let final core::int #t10 = e#case#1 = #4#0.{core::List::[]}(1){(core::int) → core::int} in true) && e#case#1.{core::num::<}(5){(core::num) → core::bool} && (let final core::int #t11 = #t5 = e#case#1 in true)) {
+        core::int e = #t5{core::int};
         {
           core::print(e);
         }
@@ -79,7 +79,7 @@ static method method(self::MyList<core::int> /* erasure=core::List<core::int> */
     final synthesized self::MyMap<core::String, core::bool> /* erasure=core::Map<core::String, core::bool> */ #5#0 = map;
     {
       hoisted core::bool e;
-      if(#5#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && (let final core::bool #t10 = e = #5#0.{core::Map::[]}(#C1){(core::Object?) → core::bool?} as{Unchecked} core::bool in true)) {
+      if(#5#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && (let final core::bool #t12 = e = let core::bool? #t13 = #5#0.{core::Map::[]}(#C1){(core::Object?) → core::bool?} in #t13 == null ?{core::bool} #t13 as{Unchecked} core::bool : #t13{core::bool} in true)) {
         {
           core::print(e);
         }
diff --git a/pkg/front_end/testcases/extensions/on_type_variable_inference2.dart.weak.transformed.expect b/pkg/front_end/testcases/extensions/on_type_variable_inference2.dart.weak.transformed.expect
index e21d050ffe6..6c4a79e1258 100644
--- a/pkg/front_end/testcases/extensions/on_type_variable_inference2.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/extensions/on_type_variable_inference2.dart.weak.transformed.expect
@@ -152,15 +152,15 @@ static method errors() → dynamic {
   self::Extension|set#property<self::Struct>(new self::Struct::•(), invalid-expression "pkg/front_end/testcases/extensions/on_type_variable_inference2.dart:52:27: Error: The value 'null' can't be assigned to a variable of type 'Struct' because 'Struct' is not nullable.
  - 'Struct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference2.dart'.
   new Struct().property = null; // error
-                          ^" in null as{TypeError,Unchecked} self::Struct);
+                          ^" in let Null #t1 = null in #t1 == null ?{self::Struct} #t1 as{TypeError} self::Struct : #t1{self::Struct});
   self::Extension|set#property<self::StructA>(new self::StructA::•(), invalid-expression "pkg/front_end/testcases/extensions/on_type_variable_inference2.dart:53:28: Error: The value 'null' can't be assigned to a variable of type 'StructA' because 'StructA' is not nullable.
  - 'StructA' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference2.dart'.
   new StructA().property = null; // error
-                           ^" in null as{TypeError,Unchecked} self::StructA);
+                           ^" in let Null #t2 = null in #t2 == null ?{self::StructA} #t2 as{TypeError} self::StructA : #t2{self::StructA});
   self::Extension|set#property<self::StructB>(new self::StructB::•(), invalid-expression "pkg/front_end/testcases/extensions/on_type_variable_inference2.dart:54:28: Error: The value 'null' can't be assigned to a variable of type 'StructB' because 'StructB' is not nullable.
  - 'StructB' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference2.dart'.
   new StructB().property = null; // error
-                           ^" in null as{TypeError,Unchecked} self::StructB);
+                           ^" in let Null #t3 = null in #t3 == null ?{self::StructB} #t3 as{TypeError} self::StructB : #t3{self::StructB});
 }
 static method testNonStruct() → dynamic {
   self::NonStruct nonStruct;
diff --git a/pkg/front_end/testcases/general/bounds_as_is.dart.weak.transformed.expect b/pkg/front_end/testcases/general/bounds_as_is.dart.weak.transformed.expect
index 99442d91917..f7ee37292c2 100644
--- a/pkg/front_end/testcases/general/bounds_as_is.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/bounds_as_is.dart.weak.transformed.expect
@@ -110,7 +110,7 @@ static method t5a(dynamic o) → dynamic
 static method t6a(dynamic o) → dynamic
   return o as self::Class<self::ConcreteClass>;
 static method t7a(dynamic o) → dynamic
-  return o as{Unchecked} core::Object;
+  return let dynamic #t1 = o in #t1 == null ?{core::Object} #t1 as core::Object : #t1{core::Object};
 static method t8a(dynamic o) → dynamic
   return o as core::int;
 static method s1a(dynamic o) → dynamic
diff --git a/pkg/front_end/testcases/general/candidate_found.dart.weak.transformed.expect b/pkg/front_end/testcases/general/candidate_found.dart.weak.transformed.expect
index b5a5a3b788d..fffd72592e8 100644
--- a/pkg/front_end/testcases/general/candidate_found.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/candidate_found.dart.weak.transformed.expect
@@ -70,6 +70,6 @@ static method test() → dynamic {
                    ^";
   invalid-expression "pkg/front_end/testcases/general/candidate_found.dart:21:24: Error: Too few positional arguments: 1 required, 0 given.
   (null as Fisk).method();
-                       ^" in (null as{Unchecked} self::Fisk).{self::Fisk::method}{<inapplicable>}.(){() → invalid-type};
+                       ^" in (let Null #t1 = null in #t1 == null ?{self::Fisk} #t1 as self::Fisk : #t1{self::Fisk}).{self::Fisk::method}{<inapplicable>}.(){() → invalid-type};
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/circularity-via-initializing-formal2.dart.weak.transformed.expect b/pkg/front_end/testcases/general/circularity-via-initializing-formal2.dart.weak.transformed.expect
index afdf079caf2..d46778e59df 100644
--- a/pkg/front_end/testcases/general/circularity-via-initializing-formal2.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/circularity-via-initializing-formal2.dart.weak.transformed.expect
@@ -24,7 +24,7 @@ class C extends core::Object {
   field self::C f = new self::C::_circular(invalid-expression "pkg/front_end/testcases/general/circularity-via-initializing-formal2.dart:14:27: Error: The value 'null' can't be assigned to the parameter type 'C' because 'C' is not nullable.
  - 'C' is from 'pkg/front_end/testcases/general/circularity-via-initializing-formal2.dart'.
   var f = new C._circular(null);
-                          ^" in null as{TypeError,Unchecked} self::C);
+                          ^" in let Null #t1 = null in #t1 == null ?{self::C} #t1 as{TypeError} self::C : #t1{self::C});
   constructor _circular(self::C f) → self::C
     : self::C::f = f, super core::Object::•()
     ;
@@ -32,5 +32,5 @@ class C extends core::Object {
 static field self::C x = new self::C::_circular(invalid-expression "pkg/front_end/testcases/general/circularity-via-initializing-formal2.dart:11:25: Error: The value 'null' can't be assigned to the parameter type 'C' because 'C' is not nullable.
  - 'C' is from 'pkg/front_end/testcases/general/circularity-via-initializing-formal2.dart'.
 var x = new C._circular(null);
-                        ^" in null as{TypeError,Unchecked} self::C);
+                        ^" in let Null #t2 = null in #t2 == null ?{self::C} #t2 as{TypeError} self::C : #t2{self::C});
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue43400.dart.weak.transformed.expect b/pkg/front_end/testcases/general/issue43400.dart.weak.transformed.expect
index 33cf91f573c..738b4c2de46 100644
--- a/pkg/front_end/testcases/general/issue43400.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/issue43400.dart.weak.transformed.expect
@@ -25,4 +25,4 @@ extension Extension<A extends core::Object? = dynamic> on self::Generic<A%> {
 static field self::Generic<invalid-type> Extension|field = invalid-expression "pkg/front_end/testcases/general/issue43400.dart:8:29: Error: The value 'null' can't be assigned to a variable of type 'Generic<invalid-type>' because 'Generic<invalid-type>' is not nullable.
  - 'Generic' is from 'pkg/front_end/testcases/general/issue43400.dart'.
   static Generic<A> field = null;
-                            ^" in null as{TypeError,Unchecked} self::Generic<invalid-type>;
+                            ^" in let Null #t1 = null in #t1 == null ?{self::Generic<invalid-type>} #t1 as{TypeError} self::Generic<invalid-type> : #t1{self::Generic<invalid-type>};
diff --git a/pkg/front_end/testcases/general/issue48090.dart.weak.transformed.expect b/pkg/front_end/testcases/general/issue48090.dart.weak.transformed.expect
index cbf022b8490..1a88bc8dbe9 100644
--- a/pkg/front_end/testcases/general/issue48090.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/issue48090.dart.weak.transformed.expect
@@ -18,5 +18,5 @@ static method main() → void {
 static method test() → void {
   core::String debugName = invalid-expression "pkg/front_end/testcases/general/issue48090.dart:12:38: Error: A value of type 'String?' can't be assigned to a variable of type 'String' because 'String?' is nullable and 'String' isn't.
   String debugName = Isolate.current.debugName; // error
-                                     ^" in iso::Isolate::current.{iso::Isolate::debugName}{core::String?} as{TypeError,Unchecked} core::String;
+                                     ^" in let core::String? #t2 = iso::Isolate::current.{iso::Isolate::debugName}{core::String?} in #t2 == null ?{core::String} #t2 as{TypeError} core::String : #t2{core::String};
 }
diff --git a/pkg/front_end/testcases/general/issue52726.dart.weak.transformed.expect b/pkg/front_end/testcases/general/issue52726.dart.weak.transformed.expect
index c10f4931d99..5b8cb5c34c5 100644
--- a/pkg/front_end/testcases/general/issue52726.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/issue52726.dart.weak.transformed.expect
@@ -19,6 +19,6 @@ class WeakMap<K extends core::Object, V extends core::Object? = dynamic> extends
     core::Object o = invalid-expression "pkg/front_end/testcases/general/issue52726.dart:10:22: Error: A value of type 'Object?' can't be assigned to a variable of type 'Object' because 'Object?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
     Object o = first.first; // Error.
-                     ^" in first.{core::Iterable::first}{core::Object?} as{TypeError,Unchecked} core::Object;
+                     ^" in let core::Object? #t1 = first.{core::Iterable::first}{core::Object?} in #t1 == null ?{core::Object} #t1 as{TypeError} core::Object : #t1{core::Object};
   }
 }
diff --git a/pkg/front_end/testcases/general/issue52973_2.dart.weak.transformed.expect b/pkg/front_end/testcases/general/issue52973_2.dart.weak.transformed.expect
index a9498a7e1f7..3bfdd95f7e9 100644
--- a/pkg/front_end/testcases/general/issue52973_2.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/issue52973_2.dart.weak.transformed.expect
@@ -17,7 +17,7 @@ static method f<X extends core::Object? = dynamic>(self::f::X? arg) → void {
     self::CheckType|expect<core::List<self::f::X%>, (core::List<self::f::X%>) → core::List<self::f::X%>>(ys);
     core::List<self::f::X?> ys2 = xs;
     self::CheckType|expect<core::List<self::f::X?>, (core::List<self::f::X?>) → core::List<self::f::X?>>(ys2);
-    core::List<core::Object> ys3 = xs as{Unchecked} core::List<core::Object>;
+    core::List<core::Object> ys3 = xs as core::List<core::Object>;
     self::CheckType|expect<core::List<core::Object>, (core::List<core::Object>) → core::List<core::Object>>(ys3);
   }
 }
diff --git a/pkg/front_end/testcases/general/nested_variance2.dart.weak.transformed.expect b/pkg/front_end/testcases/general/nested_variance2.dart.weak.transformed.expect
index 9cc9f536865..d472d47271b 100644
--- a/pkg/front_end/testcases/general/nested_variance2.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/nested_variance2.dart.weak.transformed.expect
@@ -128,7 +128,7 @@ static method testTypeAliasAsTypeArgument(self::Acov<() → dynamic, dynamic> so
   <Y extends self::Acon<(Null) → dynamic, dynamic> = dynamic>() → void target2 = invalid-expression "pkg/front_end/testcases/general/nested_variance2.dart:84:42: Error: A value of type 'void Function<Y extends Acon<dynamic Function(Never), dynamic>>()' can't be assigned to a variable of type 'void Function<Y extends Acon<dynamic Function(Null), dynamic>>()' because 'Null' is nullable and 'Never' isn't.
  - 'Acon' is from 'pkg/front_end/testcases/general/nested_variance2.dart'.
   F<Acon<Fcon<Null>, dynamic>> target2 = fsource2;
-                                         ^" in fsource2 as{TypeError,Unchecked} <Y extends self::Acon<(Null) → dynamic, dynamic> = dynamic>() → void;
+                                         ^" in fsource2 as{TypeError} <Y extends self::Acon<(Null) → dynamic, dynamic> = dynamic>() → void;
   <Y extends self::Ainv<(dynamic) → dynamic, dynamic> = dynamic>() → void fsource3 = self::toF<self::Ainv<(dynamic) → dynamic, dynamic>>(source3);
   <Y extends self::Ainv<(dynamic) → dynamic, dynamic> = dynamic>() → void target3 = fsource3;
   <Y extends self::AcovBound<() → core::num, core::num> = dynamic>() → void fsource4 = self::toF<self::AcovBound<() → core::num, core::num>>(source4);
diff --git a/pkg/front_end/testcases/general/type_variable_in_static_context.dart.weak.transformed.expect b/pkg/front_end/testcases/general/type_variable_in_static_context.dart.weak.transformed.expect
index 7ce3d60bf1b..d57309b9062 100644
--- a/pkg/front_end/testcases/general/type_variable_in_static_context.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/type_variable_in_static_context.dart.weak.transformed.expect
@@ -553,7 +553,7 @@ abstract class Mixin<T extends core::Object? = dynamic> extends core::Object /*i
     return invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:132:30: Error: The value 'null' can't be returned from a function with return type 'Mixin<T>' because 'Mixin<T>' is not nullable.
  - 'Mixin' is from 'pkg/front_end/testcases/general/type_variable_in_static_context.dart'.
   factory Mixin.fact(T t) => null;
-                             ^" in null as{TypeError,Unchecked} Never;
+                             ^" in let Null #t1 = null in #t1 == null ?{Never} #t1 as{TypeError} Never : #t1{Never};
   @invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:137:4: Error: Couldn't find constructor 'T'.
   @T()
    ^"
diff --git a/pkg/front_end/testcases/incremental/no_outline_change_22.yaml.world.1.expect b/pkg/front_end/testcases/incremental/no_outline_change_22.yaml.world.1.expect
index 17442aef9c4..8b4cdc14aeb 100644
--- a/pkg/front_end/testcases/incremental/no_outline_change_22.yaml.world.1.expect
+++ b/pkg/front_end/testcases/incremental/no_outline_change_22.yaml.world.1.expect
@@ -318,7 +318,7 @@ library from "org-dartlang-test:///main.dart" as main {
       }
     }
     method /* from org-dartlang-sdk:///sdk/lib/collection/list.dart */ fillRange(dart.core::int start, dart.core::int end, [covariant-by-class dart.core::int? fill = #C2]) → void {
-      dart.core::int value = let dart.core::int? #t6 = fill in #t6 == null ?{dart.core::int} #t6 as{Unchecked} dart.core::int : #t6{dart.core::int};
+      dart.core::int value = let dart.core::int? #t6 = fill in #t6 == null ?{dart.core::int} let dart.core::int? #t7 = #t6 in #t7 == null ?{dart.core::int} #t7 as dart.core::int : #t7{dart.core::int} : #t6{dart.core::int};
       dart.core::RangeError::checkValidRange(start, end, this.{dart.core::List::length}{dart.core::int});
       for (dart.core::int i = start; i.{dart.core::num::<}(end){(dart.core::num) → dart.core::bool}; i = i.{dart.core::num::+}(1){(dart.core::num) → dart.core::int}) {
         this.{dart.core::List::[]=}(i, value){(dart.core::int, dart.core::int) → void};
@@ -492,7 +492,7 @@ library from "org-dartlang-test:///main.dart" as main {
           for (; :sync-for-iterator.{dart.core::Iterator::moveNext}(){() → dart.core::bool}; ) {
             dart.core::int element = :sync-for-iterator.{dart.core::Iterator::current}{dart.core::int};
             {
-              this.{dart.core::List::[]=}(let final dart.core::int #t7 = index in let final dart.core::int #t8 = index = #t7.{dart.core::num::+}(1){(dart.core::num) → dart.core::int} in #t7, element){(dart.core::int, dart.core::int) → void};
+              this.{dart.core::List::[]=}(let final dart.core::int #t8 = index in let final dart.core::int #t9 = index = #t8.{dart.core::num::+}(1){(dart.core::num) → dart.core::int} in #t8, element){(dart.core::int, dart.core::int) → void};
             }
           }
         }
diff --git a/pkg/front_end/testcases/incremental/no_outline_change_22.yaml.world.2.expect b/pkg/front_end/testcases/incremental/no_outline_change_22.yaml.world.2.expect
index 17442aef9c4..8b4cdc14aeb 100644
--- a/pkg/front_end/testcases/incremental/no_outline_change_22.yaml.world.2.expect
+++ b/pkg/front_end/testcases/incremental/no_outline_change_22.yaml.world.2.expect
@@ -318,7 +318,7 @@ library from "org-dartlang-test:///main.dart" as main {
       }
     }
     method /* from org-dartlang-sdk:///sdk/lib/collection/list.dart */ fillRange(dart.core::int start, dart.core::int end, [covariant-by-class dart.core::int? fill = #C2]) → void {
-      dart.core::int value = let dart.core::int? #t6 = fill in #t6 == null ?{dart.core::int} #t6 as{Unchecked} dart.core::int : #t6{dart.core::int};
+      dart.core::int value = let dart.core::int? #t6 = fill in #t6 == null ?{dart.core::int} let dart.core::int? #t7 = #t6 in #t7 == null ?{dart.core::int} #t7 as dart.core::int : #t7{dart.core::int} : #t6{dart.core::int};
       dart.core::RangeError::checkValidRange(start, end, this.{dart.core::List::length}{dart.core::int});
       for (dart.core::int i = start; i.{dart.core::num::<}(end){(dart.core::num) → dart.core::bool}; i = i.{dart.core::num::+}(1){(dart.core::num) → dart.core::int}) {
         this.{dart.core::List::[]=}(i, value){(dart.core::int, dart.core::int) → void};
@@ -492,7 +492,7 @@ library from "org-dartlang-test:///main.dart" as main {
           for (; :sync-for-iterator.{dart.core::Iterator::moveNext}(){() → dart.core::bool}; ) {
             dart.core::int element = :sync-for-iterator.{dart.core::Iterator::current}{dart.core::int};
             {
-              this.{dart.core::List::[]=}(let final dart.core::int #t7 = index in let final dart.core::int #t8 = index = #t7.{dart.core::num::+}(1){(dart.core::num) → dart.core::int} in #t7, element){(dart.core::int, dart.core::int) → void};
+              this.{dart.core::List::[]=}(let final dart.core::int #t8 = index in let final dart.core::int #t9 = index = #t8.{dart.core::num::+}(1){(dart.core::num) → dart.core::int} in #t8, element){(dart.core::int, dart.core::int) → void};
             }
           }
         }
diff --git a/pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart.weak.transformed.expect b/pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart.weak.transformed.expect
index 2024d28be43..568021626d4 100644
--- a/pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart.weak.transformed.expect
@@ -48,7 +48,7 @@ static method foo() → dynamic {
                                                             ^" in new self::B::•().{self::B::y}{core::int} as{TypeError} core::String;
   s = invalid-expression "pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart:24:32: Error: A value of type 'String?' can't be assigned to a variable of type 'String' because 'String?' is nullable and 'String' isn't.
   s = new B(). /*@target=B.z*/ z;
-                               ^" in new self::B::•().{self::B::z}{core::String?} as{TypeError,Unchecked} core::String;
+                               ^" in let core::String? #t1 = new self::B::•().{self::B::z}{core::String?} in #t1 == null ?{core::String} #t1 as{TypeError} core::String : #t1{core::String};
   s = invalid-expression "pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart:25:61: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
   s = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.w*/ w;
                                                             ^" in new self::B::•().{self::B::w}{core::int} as{TypeError} core::String;
diff --git a/pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart.weak.transformed.expect b/pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart.weak.transformed.expect
index 7629195966a..cc7676fcde8 100644
--- a/pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart.weak.transformed.expect
@@ -110,7 +110,7 @@ static field dynamic i = invalid-expression "pkg/front_end/testcases/inference/i
 Try correcting the operator to an existing operator, or defining a 'unary-' operator.
 var i = /*error:UNDEFINED_OPERATOR,info:DYNAMIC_INVOKE*/ -new A();
                                                          ^" in new self::A::•(){<unresolved>}.unary-();
-static field self::B j = null as{Unchecked} self::B;
+static field self::B j = let Null #t2 = null in #t2 == null ?{self::B} #t2 as self::B : #t2{self::B};
 static method test1() → dynamic {
   self::a = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:36:36: Error: A value of type 'String' can't be assigned to a variable of type 'A'.
  - 'A' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
@@ -128,16 +128,16 @@ static method test1() → dynamic {
  - 'List' is from 'dart:core'.
   c1 = /*error:INVALID_ASSIGNMENT*/ /*@typeArgs=dynamic*/ {};
                                                           ^" in ( block {
-    final core::Set<dynamic> #t2 = new col::_Set::•<dynamic>();
-  } =>#t2) as{TypeError} core::List<dynamic>;
+    final core::Set<dynamic> #t3 = new col::_Set::•<dynamic>();
+  } =>#t3) as{TypeError} core::List<dynamic>;
   self::c2 = core::_GrowableList::•<dynamic>(0);
   self::c2 = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:43:59: Error: A value of type 'Set<dynamic>' can't be assigned to a variable of type 'List<dynamic>'.
  - 'Set' is from 'dart:core'.
  - 'List' is from 'dart:core'.
   c2 = /*error:INVALID_ASSIGNMENT*/ /*@typeArgs=dynamic*/ {};
                                                           ^" in ( block {
-    final core::Set<dynamic> #t3 = new col::_Set::•<dynamic>();
-  } =>#t3) as{TypeError} core::List<dynamic>;
+    final core::Set<dynamic> #t4 = new col::_Set::•<dynamic>();
+  } =>#t4) as{TypeError} core::List<dynamic>;
   self::d = <dynamic, dynamic>{};
   self::d = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:45:36: Error: A value of type 'int' can't be assigned to a variable of type 'Map<dynamic, dynamic>'.
  - 'Map' is from 'dart:core'.
@@ -183,5 +183,5 @@ constants  {
 Extra constant evaluation status:
 Evaluated: InstanceInvocation @ org-dartlang-testcase:///infer_from_complex_expressions_if_outer_most_value_is_precise.dart:27:25 -> IntConstant(5)
 Evaluated: InstanceInvocation @ org-dartlang-testcase:///infer_from_complex_expressions_if_outer_most_value_is_precise.dart:30:32 -> IntConstant(-3)
-Evaluated: AsExpression @ org-dartlang-testcase:///infer_from_complex_expressions_if_outer_most_value_is_precise.dart:33:40 -> NullConstant(null)
+Evaluated: Let @ org-dartlang-testcase:///infer_from_complex_expressions_if_outer_most_value_is_precise.dart:33:5 -> NullConstant(null)
 Extra constant evaluation: evaluated: 46, effectively constant: 3
diff --git a/pkg/front_end/testcases/inference/infer_throw_downwards.dart.weak.transformed.expect b/pkg/front_end/testcases/inference/infer_throw_downwards.dart.weak.transformed.expect
index 89437731db9..aae0fb2ac68 100644
--- a/pkg/front_end/testcases/inference/infer_throw_downwards.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/inference/infer_throw_downwards.dart.weak.transformed.expect
@@ -2,10 +2,10 @@ library test;
 import self as self;
 import "dart:core" as core;
 
-static field Never x = throw self::f<dynamic>() as{TypeError,Unchecked} core::Object;
+static field Never x = throw let dynamic #t1 = self::f<dynamic>() in #t1 == null ?{core::Object} #t1 as{TypeError} core::Object : #t1{core::Object};
 static method f<T extends core::Object? = dynamic>() → self::f::T%
   return throw "";
 static method g() → void {
-  Never x = throw self::f<dynamic>() as{TypeError,Unchecked} core::Object;
+  Never x = throw let dynamic #t2 = self::f<dynamic>() in #t2 == null ?{core::Object} #t2 as{TypeError} core::Object : #t2{core::Object};
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/strongly_connected_component.dart.weak.transformed.expect b/pkg/front_end/testcases/inference_new/strongly_connected_component.dart.weak.transformed.expect
index 459f1b7defe..86bd6fe54dd 100644
--- a/pkg/front_end/testcases/inference_new/strongly_connected_component.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/inference_new/strongly_connected_component.dart.weak.transformed.expect
@@ -20,5 +20,5 @@ static field () → invalid-type z = () → invalid-type => self::x;
 static method f() → core::bool
   return invalid-expression "pkg/front_end/testcases/inference_new/strongly_connected_component.dart:8:13: Error: The value 'null' can't be returned from a function with return type 'bool' because 'bool' is not nullable.
 bool f() => null;
-            ^" in null as{TypeError,Unchecked} core::bool;
+            ^" in let Null #t1 = null in #t1 == null ?{core::bool} #t1 as{TypeError} core::bool : #t1{core::bool};
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_update_2/abstract_field.dart.weak.transformed.expect b/pkg/front_end/testcases/inference_update_2/abstract_field.dart.weak.transformed.expect
index a491f0cf792..9ca1d8bd42c 100644
--- a/pkg/front_end/testcases/inference_update_2/abstract_field.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/inference_update_2/abstract_field.dart.weak.transformed.expect
@@ -20,7 +20,7 @@ class D extends core::Object {
 static method acceptsInt(core::int x) → void {}
 static method testAbstractFinalFieldIsPromotable(self::C c) → void {
   if(!(c.{self::C::_f1}{core::int?} == null)) {
-    core::int x = c.{self::C::_f1}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t1 = c.{self::C::_f1}{core::int?} in #t1 == null ?{core::int} #t1 as{Unchecked} core::int : #t1{core::int};
     self::acceptsInt(x);
   }
 }
@@ -32,7 +32,7 @@ static method testAbstractNonFinalFieldIsNotPromotable(self::C c) → void {
 }
 static method testAbstractFinalFieldDoesNotBlockPromotionElsewhere(self::D d) → void {
   if(!(d.{self::D::_f1}{core::int?} == null)) {
-    core::int x = d.{self::D::_f1}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t2 = d.{self::D::_f1}{core::int?} in #t2 == null ?{core::int} #t2 as{Unchecked} core::int : #t2{core::int};
     self::acceptsInt(x);
   }
 }
diff --git a/pkg/front_end/testcases/inference_update_2/basic_field_promotion.dart.weak.transformed.expect b/pkg/front_end/testcases/inference_update_2/basic_field_promotion.dart.weak.transformed.expect
index 269423e6493..7460ce1b1b7 100644
--- a/pkg/front_end/testcases/inference_update_2/basic_field_promotion.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/inference_update_2/basic_field_promotion.dart.weak.transformed.expect
@@ -20,7 +20,7 @@ abstract class C extends core::Object {
 static method acceptsInt(core::int x) → void {}
 static method testPrivateFinalField(self::C c) → void {
   if(!(c.{self::C::_privateFinalField}{core::int?} == null)) {
-    core::int x = c.{self::C::_privateFinalField}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t1 = c.{self::C::_privateFinalField}{core::int?} in #t1 == null ?{core::int} #t1 as{Unchecked} core::int : #t1{core::int};
     self::acceptsInt(x);
   }
 }
@@ -44,7 +44,7 @@ static method testPublicField(self::C c) → void {
 }
 static method testPrivateAbstractGetter(self::C c) → void {
   if(!(c.{self::C::_privateAbstractGetter}{core::int?} == null)) {
-    core::int x = c.{self::C::_privateAbstractGetter}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t2 = c.{self::C::_privateAbstractGetter}{core::int?} in #t2 == null ?{core::int} #t2 as{Unchecked} core::int : #t2{core::int};
     self::acceptsInt(x);
   }
 }
diff --git a/pkg/front_end/testcases/inference_update_2/cascaded_field_promotion.dart.weak.transformed.expect b/pkg/front_end/testcases/inference_update_2/cascaded_field_promotion.dart.weak.transformed.expect
index f5409ee91fb..01db43bbb6d 100644
--- a/pkg/front_end/testcases/inference_update_2/cascaded_field_promotion.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/inference_update_2/cascaded_field_promotion.dart.weak.transformed.expect
@@ -17,14 +17,14 @@ static method cascadedPropertyAccess(self::C c) → void {
 static method cascadedNullAwarePropertyAccess(self::C? c) → void {
   let final self::C? #t2 = c in #t2 == null ?{self::C?} null : block {
     #t2{self::C}.{self::C::_field}{core::Object?}!.{core::Object::toString}(){() → core::String};
-    (#t2{self::C}.{self::C::_field}{core::Object?} as{Unchecked} core::Object).{core::Object::toString}(){() → core::String};
+    (let core::Object? #t3 = #t2{self::C}.{self::C::_field}{core::Object?} in #t3 == null ?{core::Object} #t3 as{Unchecked} core::Object : #t3{core::Object}).{core::Object::toString}(){() → core::String};
   } =>#t2;
-  let final self::C? #t3 = c in #t3 == null ?{core::Object?} null : #t3{self::C}.{self::C::_field}{core::Object?};
+  let final self::C? #t4 = c in #t4 == null ?{core::Object?} null : #t4{self::C}.{self::C::_field}{core::Object?};
 }
 static method cascadedInvocation(self::C c) → void {
   c.{self::C::_field}{core::Object?} as () → core::int;
-  let final self::C #t4 = c in block {
-    (#t4.{self::C::_field}{core::Object?} as{Unchecked} () → core::int)(){() → core::int}.{core::int::toString}(){() → core::String};
-  } =>#t4;
+  let final self::C #t5 = c in block {
+    (#t5.{self::C::_field}{core::Object?} as{Unchecked} () → core::int)(){() → core::int}.{core::int::toString}(){() → core::String};
+  } =>#t5;
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_update_2/field_promotion_and_no_such_method.dart.weak.transformed.expect b/pkg/front_end/testcases/inference_update_2/field_promotion_and_no_such_method.dart.weak.transformed.expect
index e2acc56f3e7..55635ce7942 100644
--- a/pkg/front_end/testcases/inference_update_2/field_promotion_and_no_such_method.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/inference_update_2/field_promotion_and_no_such_method.dart.weak.transformed.expect
@@ -47,7 +47,7 @@ static method testConflictsWithNoSuchMethodForwarder(self::C c) → void {
 }
 static method testNoConflictWithNoSuchMethodForwarderForDifferentLib(self::C c) → void {
   if(!(c.{self::C::_f2}{core::int?} == null)) {
-    core::int x = c.{self::C::_f2}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t1 = c.{self::C::_f2}{core::int?} in #t1 == null ?{core::int} #t1 as{Unchecked} core::int : #t1{core::int};
     self::acceptsInt(x);
   }
 }
diff --git a/pkg/front_end/testcases/inference_update_2/field_promotion_name_conflicts.dart.weak.transformed.expect b/pkg/front_end/testcases/inference_update_2/field_promotion_name_conflicts.dart.weak.transformed.expect
index 256e8ce9c85..d622a79af94 100644
--- a/pkg/front_end/testcases/inference_update_2/field_promotion_name_conflicts.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/inference_update_2/field_promotion_name_conflicts.dart.weak.transformed.expect
@@ -58,7 +58,7 @@ static extension-member method _extension#0|get#_f10(lowered final core::String
 static method acceptsInt(core::int x) → void {}
 static method testFinalField(self::C c) → void {
   if(!(c.{self::C::_f1}{core::int?} == null)) {
-    core::int x = c.{self::C::_f1}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t1 = c.{self::C::_f1}{core::int?} in #t1 == null ?{core::int} #t1 as{Unchecked} core::int : #t1{core::int};
     self::acceptsInt(x);
   }
 }
@@ -70,7 +70,7 @@ static method testNonFinalField(self::C c) → void {
 }
 static method testAbstractGetter(self::C c) → void {
   if(!(c.{self::C::_f3}{core::int?} == null)) {
-    core::int x = c.{self::C::_f3}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t2 = c.{self::C::_f3}{core::int?} in #t2 == null ?{core::int} #t2 as{Unchecked} core::int : #t2{core::int};
     self::acceptsInt(x);
   }
 }
@@ -82,37 +82,37 @@ static method testConcreteGetter(self::C c) → void {
 }
 static method testSetter(self::C c) → void {
   if(!(c.{self::C::_f5}{core::int?} == null)) {
-    core::int x = c.{self::C::_f5}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t3 = c.{self::C::_f5}{core::int?} in #t3 == null ?{core::int} #t3 as{Unchecked} core::int : #t3{core::int};
     self::acceptsInt(x);
   }
 }
 static method testStaticField(self::C c) → void {
   if(!(c.{self::C::_f6}{core::int?} == null)) {
-    core::int x = c.{self::C::_f6}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t4 = c.{self::C::_f6}{core::int?} in #t4 == null ?{core::int} #t4 as{Unchecked} core::int : #t4{core::int};
     self::acceptsInt(x);
   }
 }
 static method testStaticGetter(self::C c) → void {
   if(!(c.{self::C::_f7}{core::int?} == null)) {
-    core::int x = c.{self::C::_f7}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t5 = c.{self::C::_f7}{core::int?} in #t5 == null ?{core::int} #t5 as{Unchecked} core::int : #t5{core::int};
     self::acceptsInt(x);
   }
 }
 static method testTopLevelField(self::C c) → void {
   if(!(c.{self::C::_f8}{core::int?} == null)) {
-    core::int x = c.{self::C::_f8}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t6 = c.{self::C::_f8}{core::int?} in #t6 == null ?{core::int} #t6 as{Unchecked} core::int : #t6{core::int};
     self::acceptsInt(x);
   }
 }
 static method testTopLevelGetter(self::C c) → void {
   if(!(c.{self::C::_f9}{core::int?} == null)) {
-    core::int x = c.{self::C::_f9}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t7 = c.{self::C::_f9}{core::int?} in #t7 == null ?{core::int} #t7 as{Unchecked} core::int : #t7{core::int};
     self::acceptsInt(x);
   }
 }
 static method testExtensionGetter(self::C c) → void {
   if(!(c.{self::C::_f10}{core::int?} == null)) {
-    core::int x = c.{self::C::_f10}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t8 = c.{self::C::_f10}{core::int?} in #t8 == null ?{core::int} #t8 as{Unchecked} core::int : #t8{core::int};
     self::acceptsInt(x);
   }
 }
diff --git a/pkg/front_end/testcases/inference_update_2/issue52452.dart.weak.transformed.expect b/pkg/front_end/testcases/inference_update_2/issue52452.dart.weak.transformed.expect
index f49be602142..abb6ad521dc 100644
--- a/pkg/front_end/testcases/inference_update_2/issue52452.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/inference_update_2/issue52452.dart.weak.transformed.expect
@@ -63,13 +63,13 @@ static method testConflictWithNoSuchMethodForwarderIfImplementedInMixin(self::C
 }
 static method testNoConflictWithNoSuchMethodForwarderIfImplementedInMixin1(self::C c) → void {
   if(!(c.{self::C::_f3}{core::int?} == null)) {
-    core::int x = c.{self::C::_f3}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t1 = c.{self::C::_f3}{core::int?} in #t1 == null ?{core::int} #t1 as{Unchecked} core::int : #t1{core::int};
     self::acceptsInt(x);
   }
 }
 static method testNoConflictWithNoSuchMethodForwarderIfImplementedInMixin2(self::C c) → void {
   if(!(c.{self::C::_f4}{core::int?} == null)) {
-    core::int x = c.{self::C::_f4}{core::int?} as{Unchecked} core::int;
+    core::int x = let core::int? #t2 = c.{self::C::_f4}{core::int?} in #t2 == null ?{core::int} #t2 as{Unchecked} core::int : #t2{core::int};
     self::acceptsInt(x);
   }
 }
diff --git a/pkg/front_end/testcases/late_lowering/caching.dart.weak.transformed.expect b/pkg/front_end/testcases/late_lowering/caching.dart.weak.transformed.expect
index 6eda0848edf..d3389ccc727 100644
--- a/pkg/front_end/testcases/late_lowering/caching.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/late_lowering/caching.dart.weak.transformed.expect
@@ -138,7 +138,7 @@ static method ifCase(dynamic o) → core::int {
   }
   {
     final synthesized dynamic #17#0 = o;
-    if(#17#0 is core::Map<core::int, core::int> && #17#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (#17#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} as{Unchecked} core::int).{core::num::>=}(#C11){(core::num) → core::bool}) {
+    if(#17#0 is core::Map<core::int, core::int> && #17#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (let core::int? #t42 = #17#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} in #t42 == null ?{core::int} #t42 as{Unchecked} core::int : #t42{core::int}).{core::num::>=}(#C11){(core::num) → core::bool}) {
       return 18;
     }
   }
@@ -190,8 +190,8 @@ static method ifCase(dynamic o) → core::int {
     synthesized core::bool #24#4#isSet = false;
     {
       hoisted core::int b;
-      if(#24#0 is core::Map<dynamic, dynamic> && #24#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t42 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int) {
-        b = (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t43 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int;
+      if(#24#0 is core::Map<dynamic, dynamic> && #24#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t43 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int) {
+        b = (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t44 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int;
         {
           return 25;
         }
@@ -220,7 +220,7 @@ static method ifCase(dynamic o) → core::int {
     final synthesized dynamic #27#0 = o;
     {
       hoisted dynamic d;
-      if(#27#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #27#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t44 = d = #27#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
+      if(#27#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #27#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t45 = d = #27#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
         return 28;
       }
     }
@@ -238,7 +238,7 @@ static method ifCaseElse(dynamic o) → core::int {
       final synthesized dynamic #1#0 = o;
       synthesized core::Object? #1#2;
       synthesized core::bool #1#2#isSet = false;
-      if(#1#0 is ({f: core::Object?}) && ((let final core::int #t45 = (#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t46 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t47 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::>=}(#C2){(core::num) → core::bool}) && (let final core::int #t48 = (#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t49 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t50 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::<}(#C3){(core::num) → core::bool}))) {
+      if(#1#0 is ({f: core::Object?}) && ((let final core::int #t46 = (#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t47 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t48 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::>=}(#C2){(core::num) → core::bool}) && (let final core::int #t49 = (#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t50 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t51 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::<}(#C3){(core::num) → core::bool}))) {
         return 2;
       }
       else {
@@ -250,12 +250,12 @@ static method ifCaseElse(dynamic o) → core::int {
           final synthesized dynamic #3#0 = o;
           synthesized core::Object? #3#2;
           synthesized core::bool #3#2#isSet = false;
-          if(#3#0 is ({g: core::Object?}) && (let final core::int #t51 = (#3#2#isSet ?{core::Object?} #3#2{core::Object?} : let final core::bool #t52 = #3#2#isSet = true in #3#2 = #3#0{({g: core::Object?})}.g{core::Object?}) as core::int in #C6 =={core::num::==}{(core::Object) → core::bool} (#3#2#isSet ?{core::Object?} #3#2{core::Object?} : let final core::bool #t53 = #3#2#isSet = true in #3#2 = #3#0{({g: core::Object?})}.g{core::Object?}) as core::int)) {
+          if(#3#0 is ({g: core::Object?}) && (let final core::int #t52 = (#3#2#isSet ?{core::Object?} #3#2{core::Object?} : let final core::bool #t53 = #3#2#isSet = true in #3#2 = #3#0{({g: core::Object?})}.g{core::Object?}) as core::int in #C6 =={core::num::==}{(core::Object) → core::bool} (#3#2#isSet ?{core::Object?} #3#2{core::Object?} : let final core::bool #t54 = #3#2#isSet = true in #3#2 = #3#0{({g: core::Object?})}.g{core::Object?}) as core::int)) {
             return 4;
           }
           else {
             final synthesized dynamic #4#0 = o;
-            if(#4#0 is ({a: core::Object?}) && (let final core::Object? #t54 = #4#0{({a: core::Object?})}.a{core::Object?}! in true)) {
+            if(#4#0 is ({a: core::Object?}) && (let final core::Object? #t55 = #4#0{({a: core::Object?})}.a{core::Object?}! in true)) {
               return 5;
             }
             else {
@@ -277,7 +277,7 @@ static method ifCaseElse(dynamic o) → core::int {
                     final synthesized dynamic #8#0 = o;
                     synthesized core::int #8#2;
                     synthesized core::bool #8#2#isSet = false;
-                    if(#8#0 is core::List<dynamic> && (#8#2#isSet ?{core::int} #8#2{core::int} : let final core::bool #t55 = #8#2#isSet = true in #8#2 = #8#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool} && #C2 =={core::num::==}{(core::Object) → core::bool} #8#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} && #C8 =={core::num::==}{(core::Object) → core::bool} #8#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic} && #C3 =={core::num::==}{(core::Object) → core::bool} #8#0{core::List<dynamic>}.{core::List::[]}((#8#2#isSet ?{core::int} #8#2{core::int} : let final core::bool #t56 = #8#2#isSet = true in #8#2 = #8#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic}) {
+                    if(#8#0 is core::List<dynamic> && (#8#2#isSet ?{core::int} #8#2{core::int} : let final core::bool #t56 = #8#2#isSet = true in #8#2 = #8#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool} && #C2 =={core::num::==}{(core::Object) → core::bool} #8#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} && #C8 =={core::num::==}{(core::Object) → core::bool} #8#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic} && #C3 =={core::num::==}{(core::Object) → core::bool} #8#0{core::List<dynamic>}.{core::List::[]}((#8#2#isSet ?{core::int} #8#2{core::int} : let final core::bool #t57 = #8#2#isSet = true in #8#2 = #8#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic}) {
                       return 9;
                     }
                     else {
@@ -288,7 +288,7 @@ static method ifCaseElse(dynamic o) → core::int {
                       synthesized core::bool #9#15#isSet = false;
                       synthesized dynamic #9#19;
                       synthesized core::bool #9#19#isSet = false;
-                      if(#9#0 is core::List<dynamic> && #9#0{core::List<dynamic>}.{core::List::length}{core::int}.{core::num::>=}(#C7){(core::num) → core::bool} && #C8 =={core::num::==}{(core::Object) → core::bool} #9#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} && #C3 =={core::num::==}{(core::Object) → core::bool} #9#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic} && ((#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t57 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t58 = (#9#15#isSet ?{dynamic} #9#15{dynamic} : let final core::bool #t59 = #9#15#isSet = true in #9#15 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t60 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#9#15#isSet ?{dynamic} #9#15{dynamic} : let final core::bool #t61 = #9#15#isSet = true in #9#15 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t62 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t63 = (#9#19#isSet ?{dynamic} #9#19{dynamic} : let final core::bool #t64 = #9#19#isSet = true in #9#19 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t65 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#9#19#isSet ?{dynamic} #9#19{dynamic} : let final core::bool #t66 = #9#19#isSet = true in #9#19 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t67 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool}))) {
+                      if(#9#0 is core::List<dynamic> && #9#0{core::List<dynamic>}.{core::List::length}{core::int}.{core::num::>=}(#C7){(core::num) → core::bool} && #C8 =={core::num::==}{(core::Object) → core::bool} #9#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} && #C3 =={core::num::==}{(core::Object) → core::bool} #9#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic} && ((#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t58 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t59 = (#9#15#isSet ?{dynamic} #9#15{dynamic} : let final core::bool #t60 = #9#15#isSet = true in #9#15 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t61 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#9#15#isSet ?{dynamic} #9#15{dynamic} : let final core::bool #t62 = #9#15#isSet = true in #9#15 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t63 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t64 = (#9#19#isSet ?{dynamic} #9#19{dynamic} : let final core::bool #t65 = #9#19#isSet = true in #9#19 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t66 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#9#19#isSet ?{dynamic} #9#19{dynamic} : let final core::bool #t67 = #9#19#isSet = true in #9#19 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t68 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool}))) {
                         return 10;
                       }
                       else {
@@ -301,7 +301,7 @@ static method ifCaseElse(dynamic o) → core::int {
                         synthesized core::bool #10#16#isSet = false;
                         synthesized dynamic #10#20;
                         synthesized core::bool #10#20#isSet = false;
-                        if(#10#0 is core::List<dynamic> && (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t68 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool} && #C3 =={core::num::==}{(core::Object) → core::bool} #10#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} && #C4 =={core::num::==}{(core::Object) → core::bool} #10#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic} && ((#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t69 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t70 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t71 = (#10#16#isSet ?{dynamic} #10#16{dynamic} : let final core::bool #t72 = #10#16#isSet = true in #10#16 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t73 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t74 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#10#16#isSet ?{dynamic} #10#16{dynamic} : let final core::bool #t75 = #10#16#isSet = true in #10#16 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t76 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t77 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t78 = (#10#20#isSet ?{dynamic} #10#20{dynamic} : let final core::bool #t79 = #10#20#isSet = true in #10#20 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t80 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t81 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#10#20#isSet ?{dynamic} #10#20{dynamic} : let final core::bool #t82 = #10#20#isSet = true in #10#20 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t83 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t84 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool})) && #C5 =={core::num::==}{(core::Object) → core::bool} #10#0{core::List<dynamic>}.{core::List::[]}((#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t85 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic}) {
+                        if(#10#0 is core::List<dynamic> && (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t69 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool} && #C3 =={core::num::==}{(core::Object) → core::bool} #10#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} && #C4 =={core::num::==}{(core::Object) → core::bool} #10#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic} && ((#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t70 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t71 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t72 = (#10#16#isSet ?{dynamic} #10#16{dynamic} : let final core::bool #t73 = #10#16#isSet = true in #10#16 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t74 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t75 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#10#16#isSet ?{dynamic} #10#16{dynamic} : let final core::bool #t76 = #10#16#isSet = true in #10#16 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t77 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t78 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t79 = (#10#20#isSet ?{dynamic} #10#20{dynamic} : let final core::bool #t80 = #10#20#isSet = true in #10#20 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t81 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t82 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#10#20#isSet ?{dynamic} #10#20{dynamic} : let final core::bool #t83 = #10#20#isSet = true in #10#20 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t84 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t85 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool})) && #C5 =={core::num::==}{(core::Object) → core::bool} #10#0{core::List<dynamic>}.{core::List::[]}((#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t86 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic}) {
                           return 11;
                         }
                         else {
@@ -336,7 +336,7 @@ static method ifCaseElse(dynamic o) → core::int {
                                     }
                                     else {
                                       final synthesized dynamic #17#0 = o;
-                                      if(#17#0 is core::Map<core::int, core::int> && #17#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (#17#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} as{Unchecked} core::int).{core::num::>=}(#C11){(core::num) → core::bool}) {
+                                      if(#17#0 is core::Map<core::int, core::int> && #17#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (let core::int? #t87 = #17#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} in #t87 == null ?{core::int} #t87 as{Unchecked} core::int : #t87{core::int}).{core::num::>=}(#C11){(core::num) → core::bool}) {
                                         return 18;
                                       }
                                       else {
@@ -380,8 +380,8 @@ static method ifCaseElse(dynamic o) → core::int {
                                                       synthesized core::bool #24#4#isSet = false;
                                                       {
                                                         hoisted core::int b;
-                                                        if(#24#0 is core::Map<dynamic, dynamic> && #24#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t86 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int) {
-                                                          b = (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t87 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int;
+                                                        if(#24#0 is core::Map<dynamic, dynamic> && #24#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t88 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int) {
+                                                          b = (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t89 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int;
                                                           {
                                                             return 25;
                                                           }
@@ -405,7 +405,7 @@ static method ifCaseElse(dynamic o) → core::int {
                                                                 final synthesized dynamic #27#0 = o;
                                                                 {
                                                                   hoisted dynamic d;
-                                                                  if(#27#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #27#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t88 = d = #27#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
+                                                                  if(#27#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #27#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t90 = d = #27#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
                                                                     return 28;
                                                                   }
                                                                   else {
@@ -493,7 +493,7 @@ static method switchStatement(dynamic o) → core::int {
       }
     }
     {
-      if(#0#0 is ({f: core::Object?}) && ((let final core::int #t89 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t90 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t91 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::>=}(#C2){(core::num) → core::bool}) && (let final core::int #t92 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t93 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t94 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::<}(#C3){(core::num) → core::bool}))) {
+      if(#0#0 is ({f: core::Object?}) && ((let final core::int #t91 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t92 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t93 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::>=}(#C2){(core::num) → core::bool}) && (let final core::int #t94 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t95 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t96 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::<}(#C3){(core::num) → core::bool}))) {
         {
           return 2;
         }
@@ -507,63 +507,63 @@ static method switchStatement(dynamic o) → core::int {
       }
     }
     {
-      if(#0#0 is ({g: core::Object?}) && (let final core::int #t95 = (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t96 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int in #C6 =={core::num::==}{(core::Object) → core::bool} (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t97 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int)) {
+      if(#0#0 is ({g: core::Object?}) && (let final core::int #t97 = (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t98 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int in #C6 =={core::num::==}{(core::Object) → core::bool} (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t99 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int)) {
         {
           return 4;
         }
       }
     }
     {
-      if(#0#0 is ({a: core::Object?}) && (let final core::Object? #t98 = (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t99 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?})}.a{core::Object?})! in true)) {
+      if(#0#0 is ({a: core::Object?}) && (let final core::Object? #t100 = (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t101 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?})}.a{core::Object?})! in true)) {
         {
           return 5;
         }
       }
     }
     {
-      if(#0#0 is ({b: core::Object?}) && (!((#0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t100 = #0#23#isSet = true in #0#23 = #0#0{({b: core::Object?})}.b{core::Object?}) == null) && true)) {
+      if(#0#0 is ({b: core::Object?}) && (!((#0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t102 = #0#23#isSet = true in #0#23 = #0#0{({b: core::Object?})}.b{core::Object?}) == null) && true)) {
         {
           return 6;
         }
       }
     }
     {
-      if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t101 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C7 && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t102 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t103 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
+      if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t103 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C7 && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t104 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t105 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
         {
           return 7;
         }
       }
     }
     {
-      if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t104 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t105 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t106 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t107 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
+      if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t106 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t107 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t108 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t109 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
         {
           return 8;
         }
       }
     }
     {
-      if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t108 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t109 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t110 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t111 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t112 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t113 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
+      if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t110 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t111 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t112 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t113 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t114 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t115 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
         {
           return 9;
         }
       }
     }
     {
-      if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t114 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t115 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t116 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t117 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t118 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t119 = (#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t120 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t121 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t122 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t123 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t124 = (#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t125 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t126 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t127 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t128 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool}))) {
+      if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t116 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t117 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t118 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t119 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t120 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t121 = (#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t122 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t123 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t124 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t125 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t126 = (#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t127 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t128 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t129 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t130 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool}))) {
         {
           return 10;
         }
       }
     }
     {
-      if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t129 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t130 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t131 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C4 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t132 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t133 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t134 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t135 = (#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t136 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t137 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t138 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t139 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t140 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t141 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t142 = (#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t143 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t144 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t145 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t146 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t147 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t148 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool})) && #C5 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t149 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t150 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
+      if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t131 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t132 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t133 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C4 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t134 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t135 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t136 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t137 = (#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t138 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t139 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t140 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t141 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t142 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t143 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t144 = (#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t145 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t146 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t147 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t148 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t149 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t150 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool})) && #C5 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t151 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t152 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
         {
           return 11;
         }
       }
     }
     {
-      if(#0#0 is self::Class && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t151 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int})) {
+      if(#0#0 is self::Class && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t153 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int})) {
         {
           return 12;
         }
@@ -577,7 +577,7 @@ static method switchStatement(dynamic o) → core::int {
       }
     }
     {
-      if(#0#0 is self::Class && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t152 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int}) && #C8 =={core::num::==}{(core::Object) → core::bool} #0#0{self::Class}.{self::Class::getter}{core::int}) {
+      if(#0#0 is self::Class && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t154 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int}) && #C8 =={core::num::==}{(core::Object) → core::bool} #0#0{self::Class}.{self::Class::getter}{core::int}) {
         {
           return 14;
         }
@@ -605,14 +605,14 @@ static method switchStatement(dynamic o) → core::int {
       }
     }
     {
-      if(#0#0 is core::Map<core::int, core::int> && #0#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (#0#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} as{Unchecked} core::int).{core::num::>=}(#C11){(core::num) → core::bool}) {
+      if(#0#0 is core::Map<core::int, core::int> && #0#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (let core::int? #t155 = #0#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} in #t155 == null ?{core::int} #t155 as{Unchecked} core::int : #t155{core::int}).{core::num::>=}(#C11){(core::num) → core::bool}) {
         {
           return 18;
         }
       }
     }
     {
-      if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t153 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C1) {
+      if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t156 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C1) {
         {
           return 19;
         }
@@ -648,7 +648,7 @@ static method switchStatement(dynamic o) → core::int {
     }
     {
       hoisted dynamic a;
-      if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool} && (let final dynamic #t154 = a = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C7){(core::Object?) → dynamic} in true)) {
+      if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool} && (let final dynamic #t157 = a = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C7){(core::Object?) → dynamic} in true)) {
         {
           return 24;
         }
@@ -656,7 +656,7 @@ static method switchStatement(dynamic o) → core::int {
     }
     {
       hoisted core::int b;
-      if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && ((#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t155 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int && (let final core::int #t156 = b = (#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t157 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int in true))) {
+      if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && ((#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t158 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int && (let final core::int #t159 = b = (#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t160 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int in true))) {
         {
           return 25;
         }
@@ -671,7 +671,7 @@ static method switchStatement(dynamic o) → core::int {
     }
     {
       hoisted dynamic c;
-      if(#0#0 is ({a: core::Object?, b: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t158 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?, b: core::Object?})}.a{core::Object?}) && (let final core::Object? #t159 = c = #0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t160 = #0#23#isSet = true in #0#23 = #0#0{({a: core::Object?, b: core::Object?})}.b{core::Object?} in true)) {
+      if(#0#0 is ({a: core::Object?, b: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t161 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?, b: core::Object?})}.a{core::Object?}) && (let final core::Object? #t162 = c = #0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t163 = #0#23#isSet = true in #0#23 = #0#0{({a: core::Object?, b: core::Object?})}.b{core::Object?} in true)) {
         {
           return 27;
         }
@@ -679,7 +679,7 @@ static method switchStatement(dynamic o) → core::int {
     }
     {
       hoisted dynamic d;
-      if(#0#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #0#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t161 = d = #0#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
+      if(#0#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #0#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t164 = d = #0#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
         {
           return 28;
         }
@@ -697,7 +697,7 @@ static method switchStatement(dynamic o) → core::int {
 static method switchExpression(dynamic o) → core::int {
   core::print("o = ${o}");
   return block {
-    core::int #t162;
+    core::int #t165;
     final synthesized dynamic #0#0 = o;
     synthesized core::Object? #0#4;
     synthesized core::bool #0#4#isSet = false;
@@ -739,139 +739,139 @@ static method switchExpression(dynamic o) → core::int {
     {
       {
         if(#C1 =={core::num::==}{(core::Object) → core::bool} #0#0) {
-          #t162 = 1;
+          #t165 = 1;
           break #L2;
         }
       }
       {
-        if(#0#0 is ({f: core::Object?}) && ((let final core::int #t163 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t164 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t165 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::>=}(#C2){(core::num) → core::bool}) && (let final core::int #t166 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t167 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t168 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::<}(#C3){(core::num) → core::bool}))) {
-          #t162 = 2;
+        if(#0#0 is ({f: core::Object?}) && ((let final core::int #t166 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t167 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t168 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::>=}(#C2){(core::num) → core::bool}) && (let final core::int #t169 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t170 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t171 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::<}(#C3){(core::num) → core::bool}))) {
+          #t165 = 2;
           break #L2;
         }
       }
       {
         if(#C4 =={core::num::==}{(core::Object) → core::bool} #0#0 || #C5 =={core::num::==}{(core::Object) → core::bool} #0#0) {
-          #t162 = 3;
+          #t165 = 3;
           break #L2;
         }
       }
       {
-        if(#0#0 is ({g: core::Object?}) && (let final core::int #t169 = (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t170 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int in #C6 =={core::num::==}{(core::Object) → core::bool} (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t171 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int)) {
-          #t162 = 4;
+        if(#0#0 is ({g: core::Object?}) && (let final core::int #t172 = (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t173 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int in #C6 =={core::num::==}{(core::Object) → core::bool} (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t174 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int)) {
+          #t165 = 4;
           break #L2;
         }
       }
       {
-        if(#0#0 is ({a: core::Object?}) && (let final core::Object? #t172 = (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t173 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?})}.a{core::Object?})! in true)) {
-          #t162 = 5;
+        if(#0#0 is ({a: core::Object?}) && (let final core::Object? #t175 = (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t176 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?})}.a{core::Object?})! in true)) {
+          #t165 = 5;
           break #L2;
         }
       }
       {
-        if(#0#0 is ({b: core::Object?}) && (!((#0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t174 = #0#23#isSet = true in #0#23 = #0#0{({b: core::Object?})}.b{core::Object?}) == null) && true)) {
-          #t162 = 6;
+        if(#0#0 is ({b: core::Object?}) && (!((#0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t177 = #0#23#isSet = true in #0#23 = #0#0{({b: core::Object?})}.b{core::Object?}) == null) && true)) {
+          #t165 = 6;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t175 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C7 && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t176 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t177 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
-          #t162 = 7;
+        if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t178 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C7 && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t179 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t180 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
+          #t165 = 7;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t178 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t179 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t180 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t181 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
-          #t162 = 8;
+        if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t181 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t182 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t183 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t184 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
+          #t165 = 8;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t182 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t183 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t184 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t185 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t186 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t187 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
-          #t162 = 9;
+        if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t185 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t186 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t187 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t188 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t189 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t190 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
+          #t165 = 9;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t188 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t189 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t190 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t191 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t192 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t193 = (#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t194 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t195 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t196 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t197 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t198 = (#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t199 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t200 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t201 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t202 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool}))) {
-          #t162 = 10;
+        if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t191 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t192 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t193 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t194 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t195 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t196 = (#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t197 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t198 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t199 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t200 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t201 = (#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t202 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t203 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t204 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t205 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool}))) {
+          #t165 = 10;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t203 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t204 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t205 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C4 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t206 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t207 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t208 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t209 = (#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t210 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t211 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t212 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t213 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t214 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t215 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t216 = (#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t217 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t218 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t219 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t220 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t221 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t222 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool})) && #C5 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t223 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t224 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
-          #t162 = 11;
+        if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t206 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t207 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t208 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C4 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t209 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t210 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t211 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t212 = (#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t213 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t214 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t215 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t216 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t217 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t218 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t219 = (#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t220 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t221 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t222 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t223 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t224 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t225 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool})) && #C5 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t226 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t227 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
+          #t165 = 11;
           break #L2;
         }
       }
       {
-        if(#0#0 is self::Class && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t225 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int})) {
-          #t162 = 12;
+        if(#0#0 is self::Class && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t228 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int})) {
+          #t165 = 12;
           break #L2;
         }
       }
       {
         if(#0#0 is self::Class && #C7 =={core::num::==}{(core::Object) → core::bool} #0#0{self::Class}.{self::Class::finalField}{core::int}) {
-          #t162 = 13;
+          #t165 = 13;
           break #L2;
         }
       }
       {
-        if(#0#0 is self::Class && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t226 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int}) && #C8 =={core::num::==}{(core::Object) → core::bool} #0#0{self::Class}.{self::Class::getter}{core::int}) {
-          #t162 = 14;
+        if(#0#0 is self::Class && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t229 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int}) && #C8 =={core::num::==}{(core::Object) → core::bool} #0#0{self::Class}.{self::Class::getter}{core::int}) {
+          #t165 = 14;
           break #L2;
         }
       }
       {
         if(#0#0 is self::Class) {
-          #t162 = 15;
+          #t165 = 15;
           break #L2;
         }
       }
       {
         if(#0#0 =={core::Object::==}{(core::Object) → core::bool} #C9) {
-          #t162 = 16;
+          #t165 = 16;
           break #L2;
         }
       }
       {
         if(#0#0 is ({e: core::Object?}) && !(#0#0{({e: core::Object?})}.e{core::Object?} =={core::Object::==}{(core::Object) → core::bool} #C10)) {
-          #t162 = 17;
+          #t165 = 17;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::Map<core::int, core::int> && #0#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (#0#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} as{Unchecked} core::int).{core::num::>=}(#C11){(core::num) → core::bool}) {
-          #t162 = 18;
+        if(#0#0 is core::Map<core::int, core::int> && #0#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (let core::int? #t230 = #0#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} in #t230 == null ?{core::int} #t230 as{Unchecked} core::int : #t230{core::int}).{core::num::>=}(#C11){(core::num) → core::bool}) {
+          #t165 = 18;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t227 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C1) {
-          #t162 = 19;
+        if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t231 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C1) {
+          #t165 = 19;
           break #L2;
         }
       }
       {
         if(#0#0 is core::bool) {
-          #t162 = 20;
+          #t165 = 20;
           break #L2;
         }
       }
       {
         if(#0#0 is core::Map<dynamic, dynamic> && o{core::Map<dynamic, dynamic>}.{core::Map::isEmpty}{core::bool}) {
-          #t162 = 21;
+          #t165 = 21;
           break #L2;
         }
       }
       {
         if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C12){(core::Object?) → core::bool} && #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C12){(core::Object?) → dynamic} is core::int) {
-          #t162 = 22;
+          #t165 = 22;
           break #L2;
         }
       }
       {
         if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C1){(core::Object?) → dynamic} is core::String) {
-          #t162 = 23;
+          #t165 = 23;
           break #L2;
         }
       }
@@ -879,48 +879,48 @@ static method switchExpression(dynamic o) → core::int {
         hoisted dynamic a;
         if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool}) {
           a = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C7){(core::Object?) → dynamic};
-          #t162 = 24;
+          #t165 = 24;
           break #L2;
         }
       }
       {
         hoisted core::int b;
-        if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t228 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int) {
-          b = (#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t229 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int;
-          #t162 = 25;
+        if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t232 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int) {
+          b = (#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t233 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int;
+          #t165 = 25;
           break #L2;
         }
       }
       {
         if(#0#0 is (core::Object?, core::Object?) && #C12 =={core::num::==}{(core::Object) → core::bool} #0#0{(core::Object?, core::Object?)}.$1{core::Object?} && #C1 =={core::num::==}{(core::Object) → core::bool} #0#0{(core::Object?, core::Object?)}.$2{core::Object?}) {
-          #t162 = 26;
+          #t165 = 26;
           break #L2;
         }
       }
       {
         hoisted dynamic c;
-        if(#0#0 is ({a: core::Object?, b: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t230 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?, b: core::Object?})}.a{core::Object?})) {
-          c = #0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t231 = #0#23#isSet = true in #0#23 = #0#0{({a: core::Object?, b: core::Object?})}.b{core::Object?};
-          #t162 = 27;
+        if(#0#0 is ({a: core::Object?, b: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t234 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?, b: core::Object?})}.a{core::Object?})) {
+          c = #0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t235 = #0#23#isSet = true in #0#23 = #0#0{({a: core::Object?, b: core::Object?})}.b{core::Object?};
+          #t165 = 27;
           break #L2;
         }
       }
       {
         hoisted dynamic d;
-        if(#0#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #0#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t232 = d = #0#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
-          #t162 = 28;
+        if(#0#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #0#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t236 = d = #0#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
+          #t165 = 28;
           break #L2;
         }
       }
       {
         if(true) {
-          #t162 = 0;
+          #t165 = 0;
           break #L2;
         }
       }
       throw{for-error-handling} new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable type.");
     }
-  } =>#t162;
+  } =>#t165;
 }
 static method test(dynamic expected, dynamic value) → dynamic {
   self::expect(expected, self::ifCase(value));
@@ -1021,4 +1021,4 @@ Evaluated: RecordLiteral @ org-dartlang-testcase:///caching.dart:331:12 -> Recor
 Evaluated: RecordLiteral @ org-dartlang-testcase:///caching.dart:332:12 -> RecordConstant(const ({c: 0, d: 1}))
 Evaluated: RecordLiteral @ org-dartlang-testcase:///caching.dart:333:12 -> RecordConstant(const ({c: 0, d: 2}))
 Evaluated: RecordLiteral @ org-dartlang-testcase:///caching.dart:334:11 -> RecordConstant(const ({c: 0, d: "foo"}))
-Extra constant evaluation: evaluated: 2729, effectively constant: 14
+Extra constant evaluation: evaluated: 2753, effectively constant: 14
diff --git a/pkg/front_end/testcases/nnbd/assignability.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/assignability.dart.weak.transformed.expect
index 01cce49b74a..88205180cf4 100644
--- a/pkg/front_end/testcases/nnbd/assignability.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/assignability.dart.weak.transformed.expect
@@ -994,7 +994,7 @@ static method ok<XnonNull extends core::Object, YnonNull extends self::ok::XnonN
   dynamicVar = xPotentiallyNullArg;
   dynamicVar = yNonNullArg;
   dynamicVar = yPotentiallyNullArg;
-  core::Object objectVar = dynamicArg as{TypeError,ForDynamic,Unchecked} core::Object;
+  core::Object objectVar = let dynamic #t1 = dynamicArg in #t1 == null ?{core::Object} #t1 as{TypeError,ForDynamic} core::Object : #t1{core::Object};
   objectVar = objectArg;
   objectVar = numArg;
   objectVar = intArg;
@@ -1014,10 +1014,10 @@ static method ok<XnonNull extends core::Object, YnonNull extends self::ok::XnonN
   core::Function functionVar = dynamicArg as{TypeError,ForDynamic} core::Function;
   functionVar = functionArg;
   functionVar = toVoidArg;
-  functionVar = let final self::Tearoffable #t1 = tearoffableArg in #t1 == null ?{() → void} null : #t1.{self::Tearoffable::call}{() → void};
+  functionVar = let final self::Tearoffable #t2 = tearoffableArg in #t2 == null ?{() → void} null : #t2.{self::Tearoffable::call}{() → void};
   () → void toVoidVar = dynamicArg as{TypeError,ForDynamic} () → void;
   toVoidVar = toVoidArg;
-  toVoidVar = let final self::Tearoffable #t2 = tearoffableArg in #t2 == null ?{() → void} null : #t2.{self::Tearoffable::call}{() → void};
+  toVoidVar = let final self::Tearoffable #t3 = tearoffableArg in #t3 == null ?{() → void} null : #t3.{self::Tearoffable::call}{() → void};
   self::Tearoffable tearoffableVar = dynamicArg as{TypeError,ForDynamic} self::Tearoffable;
   tearoffableVar = tearoffableArg;
   self::ok::XnonNull xNonNullVar = dynamicArg as{TypeError,ForDynamic} self::ok::XnonNull;
@@ -1035,57 +1035,57 @@ static method error<XnonNull extends core::Object, YnonNull extends self::error:
   core::Object objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:114:22: Error: A value of type 'Object?' can't be assigned to a variable of type 'Object' because 'Object?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   Object objectVar = objectNullableArg;
-                     ^" in objectNullableArg as{TypeError,Unchecked} core::Object;
+                     ^" in let core::Object? #t4 = objectNullableArg in #t4 == null ?{core::Object} #t4 as{TypeError} core::Object : #t4{core::Object};
   objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:115:15: Error: A value of type 'num?' can't be assigned to a variable of type 'Object' because 'num?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   objectVar = numNullableArg;
-              ^" in numNullableArg as{TypeError,Unchecked} core::Object;
+              ^" in let core::num? #t5 = numNullableArg in #t5 == null ?{core::Object} #t5 as{TypeError} core::Object : #t5{core::Object};
   objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:116:15: Error: A value of type 'int?' can't be assigned to a variable of type 'Object' because 'int?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   objectVar = intNullableArg;
-              ^" in intNullableArg as{TypeError,Unchecked} core::Object;
+              ^" in let core::int? #t6 = intNullableArg in #t6 == null ?{core::Object} #t6 as{TypeError} core::Object : #t6{core::Object};
   objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:117:15: Error: A value of type 'double?' can't be assigned to a variable of type 'Object' because 'double?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   objectVar = doubleNullableArg;
-              ^" in doubleNullableArg as{TypeError,Unchecked} core::Object;
+              ^" in let core::double? #t7 = doubleNullableArg in #t7 == null ?{core::Object} #t7 as{TypeError} core::Object : #t7{core::Object};
   objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:118:15: Error: A value of type 'Function?' can't be assigned to a variable of type 'Object' because 'Function?' is nullable and 'Object' isn't.
  - 'Function' is from 'dart:core'.
  - 'Object' is from 'dart:core'.
   objectVar = functionNullableArg;
-              ^" in functionNullableArg as{TypeError,Unchecked} core::Object;
+              ^" in let core::Function? #t8 = functionNullableArg in #t8 == null ?{core::Object} #t8 as{TypeError} core::Object : #t8{core::Object};
   objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:119:15: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'Object' because 'void Function()?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   objectVar = toVoidNullableArg;
-              ^" in toVoidNullableArg as{TypeError,Unchecked} core::Object;
+              ^" in let () →? void #t9 = toVoidNullableArg in #t9 == null ?{core::Object} #t9 as{TypeError} core::Object : #t9{core::Object};
   objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:120:15: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'Object' because 'Tearoffable?' is nullable and 'Object' isn't.
  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
  - 'Object' is from 'dart:core'.
   objectVar = tearoffableNullableArg;
-              ^" in tearoffableNullableArg as{TypeError,Unchecked} core::Object;
+              ^" in let self::Tearoffable? #t10 = tearoffableNullableArg in #t10 == null ?{core::Object} #t10 as{TypeError} core::Object : #t10{core::Object};
   objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:121:15: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'Object' because 'XnonNull?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   objectVar = xNonNullNullableArg;
-              ^" in xNonNullNullableArg as{TypeError,Unchecked} core::Object;
+              ^" in let self::error::XnonNull? #t11 = xNonNullNullableArg in #t11 == null ?{core::Object} #t11 as{TypeError} core::Object : #t11{core::Object};
   objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:122:15: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'Object' because 'XpotentiallyNull' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   objectVar = xPotentiallyNullArg;
-              ^" in xPotentiallyNullArg as{TypeError,Unchecked} core::Object;
+              ^" in let self::error::XpotentiallyNull% #t12 = xPotentiallyNullArg in #t12 == null ?{core::Object} #t12 as{TypeError} core::Object : #t12{core::Object};
   objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:123:15: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'Object' because 'XpotentiallyNull?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   objectVar = xPotentiallyNullNullableArg;
-              ^" in xPotentiallyNullNullableArg as{TypeError,Unchecked} core::Object;
+              ^" in let self::error::XpotentiallyNull? #t13 = xPotentiallyNullNullableArg in #t13 == null ?{core::Object} #t13 as{TypeError} core::Object : #t13{core::Object};
   objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:124:15: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'Object' because 'YnonNull?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   objectVar = yNonNullNullableArg;
-              ^" in yNonNullNullableArg as{TypeError,Unchecked} core::Object;
+              ^" in let self::error::YnonNull? #t14 = yNonNullNullableArg in #t14 == null ?{core::Object} #t14 as{TypeError} core::Object : #t14{core::Object};
   objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:125:15: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'Object' because 'YpotentiallyNull' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   objectVar = yPotentiallyNullArg;
-              ^" in yPotentiallyNullArg as{TypeError,Unchecked} core::Object;
+              ^" in let self::error::YpotentiallyNull% #t15 = yPotentiallyNullArg in #t15 == null ?{core::Object} #t15 as{TypeError} core::Object : #t15{core::Object};
   objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:126:15: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'Object' because 'YpotentiallyNull?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   objectVar = yPotentiallyNullNullableArg;
-              ^" in yPotentiallyNullNullableArg as{TypeError,Unchecked} core::Object;
+              ^" in let self::error::YpotentiallyNull? #t16 = yPotentiallyNullNullableArg in #t16 == null ?{core::Object} #t16 as{TypeError} core::Object : #t16{core::Object};
   core::num numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:128:16: Error: A value of type 'Object' can't be assigned to a variable of type 'num'.
  - 'Object' is from 'dart:core'.
   num numVar = objectArg;
@@ -1096,13 +1096,13 @@ static method error<XnonNull extends core::Object, YnonNull extends self::error:
            ^" in objectNullableArg as{TypeError} core::num;
   numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:130:12: Error: A value of type 'num?' can't be assigned to a variable of type 'num' because 'num?' is nullable and 'num' isn't.
   numVar = numNullableArg;
-           ^" in numNullableArg as{TypeError,Unchecked} core::num;
+           ^" in let core::num? #t17 = numNullableArg in #t17 == null ?{core::num} #t17 as{TypeError} core::num : #t17{core::num};
   numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:131:12: Error: A value of type 'int?' can't be assigned to a variable of type 'num' because 'int?' is nullable and 'num' isn't.
   numVar = intNullableArg;
-           ^" in intNullableArg as{TypeError,Unchecked} core::num;
+           ^" in let core::int? #t18 = intNullableArg in #t18 == null ?{core::num} #t18 as{TypeError} core::num : #t18{core::num};
   numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:132:12: Error: A value of type 'double?' can't be assigned to a variable of type 'num' because 'double?' is nullable and 'num' isn't.
   numVar = doubleNullableArg;
-           ^" in doubleNullableArg as{TypeError,Unchecked} core::num;
+           ^" in let core::double? #t19 = doubleNullableArg in #t19 == null ?{core::num} #t19 as{TypeError} core::num : #t19{core::num};
   numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:133:12: Error: A value of type 'Function' can't be assigned to a variable of type 'num'.
  - 'Function' is from 'dart:core'.
   numVar = functionArg;
@@ -1165,7 +1165,7 @@ static method error<XnonNull extends core::Object, YnonNull extends self::error:
            ^" in numNullableArg as{TypeError} core::int;
   intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:152:12: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
   intVar = intNullableArg;
-           ^" in intNullableArg as{TypeError,Unchecked} core::int;
+           ^" in let core::int? #t20 = intNullableArg in #t20 == null ?{core::int} #t20 as{TypeError} core::int : #t20{core::int};
   intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:153:12: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
   intVar = doubleArg;
            ^" in doubleArg as{TypeError} core::int;
@@ -1240,7 +1240,7 @@ static method error<XnonNull extends core::Object, YnonNull extends self::error:
               ^" in intNullableArg as{TypeError} core::double;
   doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:176:15: Error: A value of type 'double?' can't be assigned to a variable of type 'double' because 'double?' is nullable and 'double' isn't.
   doubleVar = doubleNullableArg;
-              ^" in doubleNullableArg as{TypeError,Unchecked} core::double;
+              ^" in let core::double? #t21 = doubleNullableArg in #t21 == null ?{core::double} #t21 as{TypeError} core::double : #t21{core::double};
   doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:177:15: Error: A value of type 'Function' can't be assigned to a variable of type 'double'.
  - 'Function' is from 'dart:core'.
   doubleVar = functionArg;
@@ -1400,7 +1400,7 @@ static method error<XnonNull extends core::Object, YnonNull extends self::error:
               ^" in functionNullableArg as{TypeError} () → void;
   toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:222:15: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'void Function()' because 'void Function()?' is nullable and 'void Function()' isn't.
   toVoidVar = toVoidNullableArg;
-              ^" in toVoidNullableArg as{TypeError,Unchecked} () → void;
+              ^" in let () →? void #t22 = toVoidNullableArg in #t22 == null ?{() → void} #t22 as{TypeError} () → void : #t22{() → void};
   toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:223:15: Error: Can't tear off method 'call' from a potentially null value.
   toVoidVar = tearoffableNullableArg;
               ^" in tearoffableNullableArg as{TypeError} () → void;
@@ -1483,7 +1483,7 @@ static method error<XnonNull extends core::Object, YnonNull extends self::error:
   tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:245:20: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'Tearoffable' because 'Tearoffable?' is nullable and 'Tearoffable' isn't.
  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
   tearoffableVar = tearoffableNullableArg;
-                   ^" in tearoffableNullableArg as{TypeError,Unchecked} self::Tearoffable;
+                   ^" in let self::Tearoffable? #t23 = tearoffableNullableArg in #t23 == null ?{self::Tearoffable} #t23 as{TypeError} self::Tearoffable : #t23{self::Tearoffable};
   tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:246:20: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'Tearoffable'.
  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
   tearoffableVar = xNonNullArg;
diff --git a/pkg/front_end/testcases/nnbd/assignability_error_messages.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/assignability_error_messages.dart.weak.transformed.expect
index fa8729eb98f..94e1068835d 100644
--- a/pkg/front_end/testcases/nnbd/assignability_error_messages.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/assignability_error_messages.dart.weak.transformed.expect
@@ -207,12 +207,12 @@ static method foo(self::B? x, core::List<self::B?> l, core::Map<self::B?, self::
  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
   fooContext(x); // Error.
-             ^" in x as{TypeError,Unchecked} self::A);
+             ^" in let self::B? #t1 = x in #t1 == null ?{self::A} #t1 as{TypeError} self::A : #t1{self::A});
   self::A a = invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:30:9: Error: A value of type 'B?' can't be assigned to a variable of type 'A' because 'B?' is nullable and 'A' isn't.
  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
   A a = x; // Error.
-        ^" in x as{TypeError,Unchecked} self::A;
+        ^" in let self::B? #t2 = x in #t2 == null ?{self::A} #t2 as{TypeError} self::A : #t2{self::A};
   core::_GrowableList::_literal1<self::A>(invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:31:10: Error: Can't assign spread elements of type 'B?' to collection elements of type 'A' because 'B?' is nullable and 'A' isn't.
  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
@@ -236,14 +236,14 @@ static method foo(self::B? x, core::List<self::B?> l, core::Map<self::B?, self::
   {
     synthesized core::Iterator<self::B?> :sync-for-iterator = l.{core::Iterable::iterator}{core::Iterator<self::B?>};
     for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
-      final self::B? #t1 = :sync-for-iterator.{core::Iterator::current}{self::B?};
+      final self::B? #t3 = :sync-for-iterator.{core::Iterator::current}{self::B?};
       {
         self::A y = invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:35:10: Error: A value of type 'B?' can't be assigned to a variable of type 'A' because 'B?' is nullable and 'A' isn't.
  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
 Try changing the type of the variable.
   for (A y in l) {} // Error.
-         ^" in #t1 as{TypeError,Unchecked} self::A;
+         ^" in let self::B? #t4 = #t3 in #t4 == null ?{self::A} #t4 as{TypeError} self::A : #t4{self::A};
       }
     }
   }
@@ -253,7 +253,7 @@ Try changing the type of the variable.
  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
  - 'Iterable' is from 'dart:core'.
   for (A y in l2) {} // Error.
-              ^" in l2 as{TypeError,Unchecked} core::Iterable<dynamic>.{core::Iterable::iterator}{core::Iterator<Never>};
+              ^" in let core::List<self::B>? #t5 = l2 in #t5 == null ?{core::Iterable<dynamic>} #t5 as{TypeError} core::Iterable<dynamic> : #t5{core::Iterable<dynamic>}.{core::Iterable::iterator}{core::Iterator<Never>};
     for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
       self::A y = :sync-for-iterator.{core::Iterator::current}{Never};
       {}
@@ -278,7 +278,7 @@ Try changing the type of the variable.
  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
       return x; // Error.
-             ^" in x as{TypeError,Unchecked} self::A;
+             ^" in let self::B? #t6 = x in #t6 == null ?{self::A} #t6 as{TypeError} self::A : #t6{self::A};
     }
     else {
       return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:47:18: Error: A value of type 'Future<B?>' can't be returned from an async function with return type 'FutureOr<A>'.
@@ -293,7 +293,7 @@ Try changing the type of the variable.
  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
   return x; // Error.
-         ^" in x as{TypeError,Unchecked} self::A;
+         ^" in let self::B? #t7 = x in #t7 == null ?{self::A} #t7 as{TypeError} self::A : #t7{self::A};
 }
 static method bar(core::List<self::B?> x, core::List<core::List<self::B?>> l, core::Map<core::List<self::B?>, core::List<self::B?>> m) → core::List<self::A> {
   self::barContext(invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:55:14: Error: The argument type 'List<B?>' can't be assigned to the parameter type 'List<A>' because 'B?' is nullable and 'A' isn't.
@@ -301,13 +301,13 @@ static method bar(core::List<self::B?> x, core::List<core::List<self::B?>> l, co
  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
   barContext(x); // Error.
-             ^" in x as{TypeError,Unchecked} core::List<self::A>);
+             ^" in x as{TypeError} core::List<self::A>);
   core::List<self::A> y = invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:56:15: Error: A value of type 'List<B?>' can't be assigned to a variable of type 'List<A>' because 'B?' is nullable and 'A' isn't.
  - 'List' is from 'dart:core'.
  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
   List<A> y = x; // Error.
-              ^" in x as{TypeError,Unchecked} core::List<self::A>;
+              ^" in x as{TypeError} core::List<self::A>;
   core::_GrowableList::_literal1<core::List<self::A>>(invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:57:16: Error: Can't assign spread elements of type 'List<B?>' to collection elements of type 'List<A>' because 'B?' is nullable and 'A' isn't.
  - 'List' is from 'dart:core'.
  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
@@ -328,7 +328,7 @@ static method bar(core::List<self::B?> x, core::List<core::List<self::B?>> l, co
   {
     synthesized core::Iterator<core::List<self::B?>> :sync-for-iterator = l.{core::Iterable::iterator}{core::Iterator<core::List<self::B?>>};
     for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
-      final core::List<self::B?> #t2 = :sync-for-iterator.{core::Iterator::current}{core::List<self::B?>};
+      final core::List<self::B?> #t8 = :sync-for-iterator.{core::Iterator::current}{core::List<self::B?>};
       {
         core::List<self::A> y = invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:59:16: Error: A value of type 'List<B?>' can't be assigned to a variable of type 'List<A>' because 'B?' is nullable and 'A' isn't.
  - 'List' is from 'dart:core'.
@@ -336,7 +336,7 @@ static method bar(core::List<self::B?> x, core::List<core::List<self::B?>> l, co
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
 Try changing the type of the variable.
   for (List<A> y in l) {} // Error.
-               ^" in #t2 as{TypeError,Unchecked} core::List<self::A>;
+               ^" in #t8 as{TypeError} core::List<self::A>;
       }
     }
   }
@@ -345,48 +345,48 @@ Try changing the type of the variable.
  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
   return x; // Error.
-         ^" in x as{TypeError,Unchecked} core::List<self::A>;
+         ^" in x as{TypeError} core::List<self::A>;
 }
 static method baz(self::C c) → void {
   self::bazContext(invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:64:14: Error: The argument type 'num? Function()' can't be assigned to the parameter type 'num Function()' because 'num?' is nullable and 'num' isn't.
   bazContext(c);
-             ^" in (let final self::C #t3 = c in #t3 == null ?{() → core::num?} null : #t3.{self::C::call}{() → core::num?}) as{TypeError,Unchecked} () → core::num);
+             ^" in (let final self::C #t9 = c in #t9 == null ?{() → core::num?} null : #t9.{self::C::call}{() → core::num?}) as{TypeError} () → core::num);
 }
 static method boz(Null x) → self::A {
   self::fooContext(invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:68:14: Error: The argument type 'Null' can't be assigned to the parameter type 'A' because 'A' is not nullable.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
   fooContext(x); // Error.
-             ^" in x as{TypeError,Unchecked} self::A);
+             ^" in let Null #t10 = x in #t10 == null ?{self::A} #t10 as{TypeError} self::A : #t10{self::A});
   self::fooContext(invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:69:14: Error: The value 'null' can't be assigned to the parameter type 'A' because 'A' is not nullable.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
   fooContext(null); // Error.
-             ^" in null as{TypeError,Unchecked} self::A);
+             ^" in let Null #t11 = null in #t11 == null ?{self::A} #t11 as{TypeError} self::A : #t11{self::A});
   self::A a1 = invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:70:10: Error: A value of type 'Null' can't be assigned to a variable of type 'A' because 'A' is not nullable.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
   A a1 = x; // Error.
-         ^" in x as{TypeError,Unchecked} self::A;
+         ^" in let Null #t12 = x in #t12 == null ?{self::A} #t12 as{TypeError} self::A : #t12{self::A};
   self::A a2 = invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:71:10: Error: The value 'null' can't be assigned to a variable of type 'A' because 'A' is not nullable.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
   A a2 = null; // Error.
-         ^" in null as{TypeError,Unchecked} self::A;
+         ^" in let Null #t13 = null in #t13 == null ?{self::A} #t13 as{TypeError} self::A : #t13{self::A};
   if(true) {
     return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:73:12: Error: A value of type 'Null' can't be returned from a function with return type 'A' because 'A' is not nullable.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
     return x; // Error.
-           ^" in x as{TypeError,Unchecked} self::A;
+           ^" in let Null #t14 = x in #t14 == null ?{self::A} #t14 as{TypeError} self::A : #t14{self::A};
   }
   else {
     return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:75:12: Error: The value 'null' can't be returned from a function with return type 'A' because 'A' is not nullable.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
     return null; // Error.
-           ^" in null as{TypeError,Unchecked} self::A;
+           ^" in let Null #t15 = null in #t15 == null ?{self::A} #t15 as{TypeError} self::A : #t15{self::A};
   }
   function local() → FutureOr<self::A> async /* emittedValueType= self::A */ {
     if(true) {
       return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:79:14: Error: The value 'null' can't be returned from an async function with return type 'FutureOr<A>' because 'FutureOr<A>' is not nullable.
  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
       return null; // Error.
-             ^" in null as{TypeError,Unchecked} self::A;
+             ^" in let Null #t16 = null in #t16 == null ?{self::A} #t16 as{TypeError} self::A : #t16{self::A};
     }
     else {
       return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:81:18: Error: A value of type 'Future<Null>' can't be returned from an async function with return type 'FutureOr<A>'.
diff --git a/pkg/front_end/testcases/nnbd/forin.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/forin.dart.weak.transformed.expect
index 9833e23eacb..cd6bf1a6b15 100644
--- a/pkg/front_end/testcases/nnbd/forin.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/forin.dart.weak.transformed.expect
@@ -56,31 +56,7 @@ static method error(core::Iterable<core::int>? i2, core::List<core::int>? l2, co
     synthesized core::Iterator<Never> :sync-for-iterator = invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:9:17: Error: The type 'Iterable<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'Iterable<int>?' is nullable and 'Iterable<dynamic>' isn't.
  - 'Iterable' is from 'dart:core'.
   for (int x in i2) x;
-                ^" in i2 as{TypeError,Unchecked} core::Iterable<dynamic>.{core::Iterable::iterator}{core::Iterator<Never>};
-    for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
-      core::int x = :sync-for-iterator.{core::Iterator::current}{Never};
-      x;
-    }
-  }
-  {
-    final core::List<core::int> #t1 = core::_GrowableList::•<core::int>(0);
-    {
-      synthesized core::Iterator<Never> :sync-for-iterator = invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:10:18: Error: The type 'Iterable<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'Iterable<int>?' is nullable and 'Iterable<dynamic>' isn't.
- - 'Iterable' is from 'dart:core'.
-  [for (int x in i2) x];
-                 ^" in i2 as{TypeError,Unchecked} core::Iterable<dynamic>.{core::Iterable::iterator}{core::Iterator<Never>};
-      for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
-        core::int x = :sync-for-iterator.{core::Iterator::current}{Never};
-        #t1.{core::List::add}{Invariant}(x){(core::int) → void};
-      }
-    }
-  }
-  {
-    synthesized core::Iterator<Never> :sync-for-iterator = invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:12:17: Error: The type 'List<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'List<int>?' is nullable and 'Iterable<dynamic>' isn't.
- - 'List' is from 'dart:core'.
- - 'Iterable' is from 'dart:core'.
-  for (int x in l2) x;
-                ^" in l2 as{TypeError,Unchecked} core::Iterable<dynamic>.{core::Iterable::iterator}{core::Iterator<Never>};
+                ^" in let core::Iterable<core::int>? #t1 = i2 in #t1 == null ?{core::Iterable<dynamic>} #t1 as{TypeError} core::Iterable<dynamic> : #t1{core::Iterable<dynamic>}.{core::Iterable::iterator}{core::Iterator<Never>};
     for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
       core::int x = :sync-for-iterator.{core::Iterator::current}{Never};
       x;
@@ -88,15 +64,39 @@ static method error(core::Iterable<core::int>? i2, core::List<core::int>? l2, co
   }
   {
     final core::List<core::int> #t2 = core::_GrowableList::•<core::int>(0);
+    {
+      synthesized core::Iterator<Never> :sync-for-iterator = invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:10:18: Error: The type 'Iterable<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'Iterable<int>?' is nullable and 'Iterable<dynamic>' isn't.
+ - 'Iterable' is from 'dart:core'.
+  [for (int x in i2) x];
+                 ^" in let core::Iterable<core::int>? #t3 = i2 in #t3 == null ?{core::Iterable<dynamic>} #t3 as{TypeError} core::Iterable<dynamic> : #t3{core::Iterable<dynamic>}.{core::Iterable::iterator}{core::Iterator<Never>};
+      for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
+        core::int x = :sync-for-iterator.{core::Iterator::current}{Never};
+        #t2.{core::List::add}{Invariant}(x){(core::int) → void};
+      }
+    }
+  }
+  {
+    synthesized core::Iterator<Never> :sync-for-iterator = invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:12:17: Error: The type 'List<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'List<int>?' is nullable and 'Iterable<dynamic>' isn't.
+ - 'List' is from 'dart:core'.
+ - 'Iterable' is from 'dart:core'.
+  for (int x in l2) x;
+                ^" in let core::List<core::int>? #t4 = l2 in #t4 == null ?{core::Iterable<dynamic>} #t4 as{TypeError} core::Iterable<dynamic> : #t4{core::Iterable<dynamic>}.{core::Iterable::iterator}{core::Iterator<Never>};
+    for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
+      core::int x = :sync-for-iterator.{core::Iterator::current}{Never};
+      x;
+    }
+  }
+  {
+    final core::List<core::int> #t5 = core::_GrowableList::•<core::int>(0);
     {
       synthesized core::Iterator<Never> :sync-for-iterator = invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:13:18: Error: The type 'List<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'List<int>?' is nullable and 'Iterable<dynamic>' isn't.
  - 'List' is from 'dart:core'.
  - 'Iterable' is from 'dart:core'.
   [for (int x in l2) x];
-                 ^" in l2 as{TypeError,Unchecked} core::Iterable<dynamic>.{core::Iterable::iterator}{core::Iterator<Never>};
+                 ^" in let core::List<core::int>? #t6 = l2 in #t6 == null ?{core::Iterable<dynamic>} #t6 as{TypeError} core::Iterable<dynamic> : #t6{core::Iterable<dynamic>}.{core::Iterable::iterator}{core::Iterator<Never>};
       for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
         core::int x = :sync-for-iterator.{core::Iterator::current}{Never};
-        #t2.{core::List::add}{Invariant}(x){(core::int) → void};
+        #t5.{core::List::add}{Invariant}(x){(core::int) → void};
       }
     }
   }
@@ -107,15 +107,15 @@ static method error(core::Iterable<core::int>? i2, core::List<core::int>? l2, co
   for (int x in o1) x;
                 ^" in o1 as{TypeError} core::Iterable<dynamic>.{core::Iterable::iterator}{core::Iterator<Never>};
     for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
-      final dynamic #t3 = :sync-for-iterator.{core::Iterator::current}{Never};
+      final dynamic #t7 = :sync-for-iterator.{core::Iterator::current}{Never};
       {
-        core::int x = #t3 as{TypeError,ForDynamic} core::int;
+        core::int x = #t7 as{TypeError,ForDynamic} core::int;
         x;
       }
     }
   }
   {
-    final core::List<core::int> #t4 = core::_GrowableList::•<core::int>(0);
+    final core::List<core::int> #t8 = core::_GrowableList::•<core::int>(0);
     {
       synthesized core::Iterator<Never> :sync-for-iterator = invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:16:18: Error: The type 'Object' used in the 'for' loop must implement 'Iterable<dynamic>'.
  - 'Object' is from 'dart:core'.
@@ -123,10 +123,10 @@ static method error(core::Iterable<core::int>? i2, core::List<core::int>? l2, co
   [for (int x in o1) x];
                  ^" in o1 as{TypeError} core::Iterable<dynamic>.{core::Iterable::iterator}{core::Iterator<Never>};
       for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
-        final dynamic #t5 = :sync-for-iterator.{core::Iterator::current}{Never};
+        final dynamic #t9 = :sync-for-iterator.{core::Iterator::current}{Never};
         {
-          core::int x = #t5 as{TypeError,ForDynamic} core::int;
-          #t4.{core::List::add}{Invariant}(x){(core::int) → void};
+          core::int x = #t9 as{TypeError,ForDynamic} core::int;
+          #t8.{core::List::add}{Invariant}(x){(core::int) → void};
         }
       }
     }
@@ -138,15 +138,15 @@ static method error(core::Iterable<core::int>? i2, core::List<core::int>? l2, co
   for (int x in o2) x;
                 ^" in o2 as{TypeError} core::Iterable<dynamic>.{core::Iterable::iterator}{core::Iterator<Never>};
     for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
-      final dynamic #t6 = :sync-for-iterator.{core::Iterator::current}{Never};
+      final dynamic #t10 = :sync-for-iterator.{core::Iterator::current}{Never};
       {
-        core::int x = #t6 as{TypeError,ForDynamic} core::int;
+        core::int x = #t10 as{TypeError,ForDynamic} core::int;
         x;
       }
     }
   }
   {
-    final core::List<core::int> #t7 = core::_GrowableList::•<core::int>(0);
+    final core::List<core::int> #t11 = core::_GrowableList::•<core::int>(0);
     {
       synthesized core::Iterator<Never> :sync-for-iterator = invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:19:18: Error: The type 'Object?' used in the 'for' loop must implement 'Iterable<dynamic>'.
  - 'Object' is from 'dart:core'.
@@ -154,10 +154,10 @@ static method error(core::Iterable<core::int>? i2, core::List<core::int>? l2, co
   [for (int x in o2) x];
                  ^" in o2 as{TypeError} core::Iterable<dynamic>.{core::Iterable::iterator}{core::Iterator<Never>};
       for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
-        final dynamic #t8 = :sync-for-iterator.{core::Iterator::current}{Never};
+        final dynamic #t12 = :sync-for-iterator.{core::Iterator::current}{Never};
         {
-          core::int x = #t8 as{TypeError,ForDynamic} core::int;
-          #t7.{core::List::add}{Invariant}(x){(core::int) → void};
+          core::int x = #t12 as{TypeError,ForDynamic} core::int;
+          #t11.{core::List::add}{Invariant}(x){(core::int) → void};
         }
       }
     }
@@ -172,12 +172,12 @@ static method ok(core::Iterable<core::int> i1, core::List<core::int> l1, dynamic
     }
   }
   {
-    final core::List<core::int> #t9 = core::_GrowableList::•<core::int>(0);
+    final core::List<core::int> #t13 = core::_GrowableList::•<core::int>(0);
     {
       synthesized core::Iterator<core::int> :sync-for-iterator = i1.{core::Iterable::iterator}{core::Iterator<core::int>};
       for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
         core::int x = :sync-for-iterator.{core::Iterator::current}{core::int};
-        #t9.{core::List::add}{Invariant}(x){(core::int) → void};
+        #t13.{core::List::add}{Invariant}(x){(core::int) → void};
       }
     }
   }
@@ -189,34 +189,34 @@ static method ok(core::Iterable<core::int> i1, core::List<core::int> l1, dynamic
     }
   }
   {
-    final core::List<core::int> #t10 = core::_GrowableList::•<core::int>(0);
+    final core::List<core::int> #t14 = core::_GrowableList::•<core::int>(0);
     {
       synthesized core::Iterator<core::int> :sync-for-iterator = l1.{core::Iterable::iterator}{core::Iterator<core::int>};
       for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
         core::int x = :sync-for-iterator.{core::Iterator::current}{core::int};
-        #t10.{core::List::add}{Invariant}(x){(core::int) → void};
+        #t14.{core::List::add}{Invariant}(x){(core::int) → void};
       }
     }
   }
   {
     synthesized core::Iterator<dynamic> :sync-for-iterator = (d as{TypeError,ForDynamic} core::Iterable<dynamic>).{core::Iterable::iterator}{core::Iterator<dynamic>};
     for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
-      final dynamic #t11 = :sync-for-iterator.{core::Iterator::current}{dynamic};
+      final dynamic #t15 = :sync-for-iterator.{core::Iterator::current}{dynamic};
       {
-        core::int x = #t11 as{TypeError,ForDynamic} core::int;
+        core::int x = #t15 as{TypeError,ForDynamic} core::int;
         x;
       }
     }
   }
   {
-    final core::List<core::int> #t12 = core::_GrowableList::•<core::int>(0);
+    final core::List<core::int> #t16 = core::_GrowableList::•<core::int>(0);
     {
       synthesized core::Iterator<dynamic> :sync-for-iterator = (d as{TypeError,ForDynamic} core::Iterable<dynamic>).{core::Iterable::iterator}{core::Iterator<dynamic>};
       for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
-        final dynamic #t13 = :sync-for-iterator.{core::Iterator::current}{dynamic};
+        final dynamic #t17 = :sync-for-iterator.{core::Iterator::current}{dynamic};
         {
-          core::int x = #t13 as{TypeError,ForDynamic} core::int;
-          #t12.{core::List::add}{Invariant}(x){(core::int) → void};
+          core::int x = #t17 as{TypeError,ForDynamic} core::int;
+          #t16.{core::List::add}{Invariant}(x){(core::int) → void};
         }
       }
     }
diff --git a/pkg/front_end/testcases/nnbd/issue41102.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue41102.dart.weak.transformed.expect
index a3bee522406..369ef0bd993 100644
--- a/pkg/front_end/testcases/nnbd/issue41102.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue41102.dart.weak.transformed.expect
@@ -67,7 +67,7 @@ static final field core::List<dynamic> s1 = core::_GrowableList::•<dynamic>(0)
 static final field core::int? s2 = let final core::List<dynamic> #t1 = self::s1 in #t1 == null ?{core::int?} null : #t1.{core::List::length}{core::int};
 static final field core::List<core::int> s3 = core::_List::filled<core::int>(2, invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:19:36: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
 final s3 = new List<int>.filled(2, null);
-                                   ^" in null as{TypeError,Unchecked} core::int);
+                                   ^" in let Null #t2 = null in #t2 == null ?{core::int} #t2 as{TypeError} core::int : #t2{core::int});
 static final field dynamic s4 = (() → Null {
   core::int e = 0;
   switch(e) /* core::int */ {
@@ -91,10 +91,10 @@ static final field dynamic s8 = invalid-expression "pkg/front_end/testcases/nnbd
  - 'List' is from 'dart:core'.
 final s8 = s7[0];
              ^" in self::s7.{core::List::[]}{<nullable>}.(0){(core::int) → dynamic};
-static final field core::int s9 = let final core::List<dynamic>? #t2 = self::s7 in let final core::int #t3 = 0 in let final core::int #t4 = 0 in let final void #t5 = invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:39:14: Error: Operator '[]=' cannot be called on 'List<dynamic>?' because it is potentially null.
+static final field core::int s9 = let final core::List<dynamic>? #t3 = self::s7 in let final core::int #t4 = 0 in let final core::int #t5 = 0 in let final void #t6 = invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:39:14: Error: Operator '[]=' cannot be called on 'List<dynamic>?' because it is potentially null.
  - 'List' is from 'dart:core'.
 final s9 = s7[0] = 0;
-             ^" in #t2.{core::List::[]=}{<nullable>}.(#t3, #t4){(core::int, dynamic) → void} in #t4;
+             ^" in #t3.{core::List::[]=}{<nullable>}.(#t4, #t5){(core::int, dynamic) → void} in #t5;
 static final field core::int s10 = invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:41:16: Error: Property 'length' cannot be accessed on 'List<dynamic>?' because it is potentially null.
  - 'List' is from 'dart:core'.
 Try accessing using ?. instead.
diff --git a/pkg/front_end/testcases/nnbd/issue41108.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue41108.dart.weak.transformed.expect
index ba02f1d7053..dfff98d8731 100644
--- a/pkg/front_end/testcases/nnbd/issue41108.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue41108.dart.weak.transformed.expect
@@ -15,7 +15,7 @@ static method test() → dynamic async /* emittedValueType= dynamic */ {
   core::List<dynamic> y = invalid-expression "pkg/front_end/testcases/nnbd/issue41108.dart:6:12: Error: A value of type 'List<dynamic>?' can't be assigned to a variable of type 'List<dynamic>' because 'List<dynamic>?' is nullable and 'List<dynamic>' isn't.
  - 'List' is from 'dart:core'.
   List y = await l(); // should be a List?
-           ^" in await self::l() /* runtimeCheckType= asy::Future<core::List<dynamic>?> */ as{TypeError,Unchecked} core::List<dynamic>;
+           ^" in let core::List<dynamic>? #t1 = await self::l() /* runtimeCheckType= asy::Future<core::List<dynamic>?> */ in #t1 == null ?{core::List<dynamic>} #t1 as{TypeError} core::List<dynamic> : #t1{core::List<dynamic>};
 }
 static method l() → asy::Future<core::List<dynamic>>?
   return null;
diff --git a/pkg/front_end/testcases/nnbd/issue41700b.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue41700b.dart.weak.transformed.expect
index 01b6e3cffa4..1cba2d36123 100644
--- a/pkg/front_end/testcases/nnbd/issue41700b.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue41700b.dart.weak.transformed.expect
@@ -31,7 +31,7 @@ static method test() → dynamic {
   self::Null x = invalid-expression "pkg/front_end/testcases/nnbd/issue41700b.dart:8:12: Error: The value 'null' can't be assigned to a variable of type 'Null' because 'Null' is not nullable.
  - 'Null' is from 'pkg/front_end/testcases/nnbd/issue41700b.dart'.
   Null x = null;
-           ^" in null as{TypeError,Unchecked} self::Null;
+           ^" in let Null #t1 = null in #t1 == null ?{self::Null} #t1 as{TypeError} self::Null : #t1{self::Null};
   invalid-expression "pkg/front_end/testcases/nnbd/issue41700b.dart:9:5: Error: The method 'foo' isn't defined for the class 'Null'.
  - 'Null' is from 'pkg/front_end/testcases/nnbd/issue41700b.dart'.
 Try correcting the name to the name of an existing method, or defining a method named 'foo'.
diff --git a/pkg/front_end/testcases/nnbd/issue42089.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue42089.dart.weak.transformed.expect
index 92b59a6dd6b..7c03e706c9a 100644
--- a/pkg/front_end/testcases/nnbd/issue42089.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue42089.dart.weak.transformed.expect
@@ -20,11 +20,11 @@ static method test<X extends core::Object? = dynamic>(self::test::X? x) → dyna
     core::Object o = invalid-expression "pkg/front_end/testcases/nnbd/issue42089.dart:7:16: Error: A value of type 'X?' can't be assigned to a variable of type 'Object' because 'X?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
     Object o = x;
-               ^" in x{self::test::X? & core::String? /* '?' & '?' = '?' */} as{TypeError,Unchecked} core::Object;
+               ^" in let self::test::X? & core::String? /* '?' & '?' = '?' */ #t1 = x{self::test::X? & core::String? /* '?' & '?' = '?' */} in #t1 == null ?{core::Object} #t1 as{TypeError} core::Object : #t1{core::Object};
     o = invalid-expression "pkg/front_end/testcases/nnbd/issue42089.dart:8:9: Error: A value of type 'X?' can't be assigned to a variable of type 'Object' because 'X?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
     o = x;
-        ^" in x{self::test::X? & core::String? /* '?' & '?' = '?' */} as{TypeError,Unchecked} core::Object;
+        ^" in let self::test::X? & core::String? /* '?' & '?' = '?' */ #t2 = x{self::test::X? & core::String? /* '?' & '?' = '?' */} in #t2 == null ?{core::Object} #t2 as{TypeError} core::Object : #t2{core::Object};
   }
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42362.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue42362.dart.weak.transformed.expect
index 399885c717e..9cc6771f258 100644
--- a/pkg/front_end/testcases/nnbd/issue42362.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue42362.dart.weak.transformed.expect
@@ -118,12 +118,12 @@ class A extends core::Object {
   constructor constructor5([core::int? i = #C1]) → self::A
     : self::A::i = invalid-expression "pkg/front_end/testcases/nnbd/issue42362.dart:19:18: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
       : this.i = i; // error
-                 ^" in i as{TypeError,Unchecked} core::int, super core::Object::•()
+                 ^" in let core::int? #t1 = i in #t1 == null ?{core::int} #t1 as{TypeError} core::int : #t1{core::int}, super core::Object::•()
     ;
   constructor constructor6({core::int? i = #C1}) → self::A
     : self::A::i = invalid-expression "pkg/front_end/testcases/nnbd/issue42362.dart:22:18: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
       : this.i = i; // error
-                 ^" in i as{TypeError,Unchecked} core::int, super core::Object::•()
+                 ^" in let core::int? #t2 = i in #t2 == null ?{core::int} #t2 as{TypeError} core::int : #t2{core::int}, super core::Object::•()
     ;
   constructor constructor7({required core::int i}) → self::A
     : self::A::i = i, super core::Object::•()
@@ -180,12 +180,12 @@ class C extends core::Object implements self::B {
   constructor constructor5([core::int? i = #C1]) → self::C
     : self::C::i = invalid-expression "pkg/front_end/testcases/nnbd/issue42362.dart:85:39: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
   C.constructor5([int? i]) : this.i = i; // error
-                                      ^" in i as{TypeError,Unchecked} core::int, super core::Object::•()
+                                      ^" in let core::int? #t3 = i in #t3 == null ?{core::int} #t3 as{TypeError} core::int : #t3{core::int}, super core::Object::•()
     ;
   constructor constructor6({core::int? i = #C1}) → self::C
     : self::C::i = invalid-expression "pkg/front_end/testcases/nnbd/issue42362.dart:87:39: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
   C.constructor6({int? i}) : this.i = i; // error
-                                      ^" in i as{TypeError,Unchecked} core::int, super core::Object::•()
+                                      ^" in let core::int? #t4 = i in #t4 == null ?{core::int} #t4 as{TypeError} core::int : #t4{core::int}, super core::Object::•()
     ;
   constructor constructor7({required core::int i}) → self::C
     : self::C::i = i, super core::Object::•()
diff --git a/pkg/front_end/testcases/nnbd/issue42540.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue42540.dart.weak.transformed.expect
index d34acd00b63..2ce4f17f6b9 100644
--- a/pkg/front_end/testcases/nnbd/issue42540.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue42540.dart.weak.transformed.expect
@@ -6,7 +6,7 @@ import "dart:core" as core;
 static method getNull() → dynamic
   return null;
 static method fn() → asy::Future<core::Object> async /* emittedValueType= core::Object */ {
-  core::Object o = await self::getNull() /* runtimeCheckType= asy::Future<dynamic> */ as{TypeError,ForDynamic,Unchecked} core::Object;
-  return await self::getNull() /* runtimeCheckType= asy::Future<dynamic> */ as{TypeError,ForDynamic,Unchecked} FutureOr<core::Object>;
+  core::Object o = let dynamic #t1 = await self::getNull() /* runtimeCheckType= asy::Future<dynamic> */ in #t1 == null ?{core::Object} #t1 as{TypeError,ForDynamic} core::Object : #t1{core::Object};
+  return let dynamic #t2 = await self::getNull() /* runtimeCheckType= asy::Future<dynamic> */ in #t2 == null ?{FutureOr<core::Object>} #t2 as{TypeError,ForDynamic} FutureOr<core::Object> : #t2{FutureOr<core::Object>};
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue43716a.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue43716a.dart.weak.transformed.expect
index 1e3611cf927..2824d0a301d 100644
--- a/pkg/front_end/testcases/nnbd/issue43716a.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue43716a.dart.weak.transformed.expect
@@ -22,7 +22,7 @@ class C<X extends self::C<self::C::X%, self::C::X%>? = self::C<dynamic, dynamic>
     return invalid-expression "pkg/front_end/testcases/nnbd/issue43716a.dart:15:14: Error: A value of type 'Object?' can't be returned from a function with return type 'Object' because 'Object?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
     return z.x; // Error.
-             ^" in z{self::C<core::Object?, core::Object?>}.{self::C::x}{core::Object?} as{TypeError,Unchecked} core::Object;
+             ^" in let core::Object? #t1 = z{self::C<core::Object?, core::Object?>}.{self::C::x}{core::Object?} in #t1 == null ?{core::Object} #t1 as{TypeError} core::Object : #t1{core::Object};
   }
 }
 static field core::bool b = true;
diff --git a/pkg/front_end/testcases/nnbd/issue43721.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue43721.dart.weak.transformed.expect
index a00a6625938..dda096c6617 100644
--- a/pkg/front_end/testcases/nnbd/issue43721.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue43721.dart.weak.transformed.expect
@@ -20,6 +20,6 @@ static method bar(core::bool condition) → dynamic {
   self::foo(invalid-expression "pkg/front_end/testcases/nnbd/issue43721.dart:13:7: Error: The argument type 'FutureOr<num?>' can't be assigned to the parameter type 'Object' because 'num?' is nullable and 'Object' isn't.
  - 'Object' is from 'dart:core'.
   foo(z); // Error.
-      ^" in z as{TypeError,Unchecked} core::Object);
+      ^" in let FutureOr<core::num?>#t1 = z in #t1 == null ?{core::Object} #t1 as{TypeError} core::Object : #t1{core::Object});
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue49198.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue49198.dart.weak.transformed.expect
index 02bd41d9f9a..9a57b423566 100644
--- a/pkg/front_end/testcases/nnbd/issue49198.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue49198.dart.weak.transformed.expect
@@ -5,7 +5,7 @@ import "dart:core" as core;
 static final field core::bool inSoundMode = !(core::_GrowableList::•<core::int?>(0) is core::List<core::int>);
 static method main() → dynamic {
   try {
-    throw (null as dynamic) as{TypeError,Unchecked} core::Object;
+    throw let dynamic #t1 = null as dynamic in #t1 == null ?{core::Object} #t1 as{TypeError} core::Object : #t1{core::Object};
   }
   on core::TypeError catch(final core::TypeError e) {
     core::print("${e.{core::Object::runtimeType}{core::Type}}:${e}");
@@ -14,5 +14,5 @@ static method main() → dynamic {
 
 
 Extra constant evaluation status:
-Evaluated: AsExpression @ org-dartlang-testcase:///issue49198.dart:9:16 -> NullConstant(null)
+Evaluated: Let @ org-dartlang-testcase:///issue49198.dart:9:5 -> NullConstant(null)
 Extra constant evaluation: evaluated: 10, effectively constant: 1
diff --git a/pkg/front_end/testcases/nnbd/null_shorting_index.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/null_shorting_index.dart.weak.transformed.expect
index 178f0d5291f..12abc2cc281 100644
--- a/pkg/front_end/testcases/nnbd/null_shorting_index.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/null_shorting_index.dart.weak.transformed.expect
@@ -68,13 +68,13 @@ static method main() → dynamic {
   let final self::Class1? #t75 = c1 in #t75 == null ?{core::int?} null : let final self::Class2? #t76 = #t75{self::Class1}.{self::Class1::field}{self::Class2?} in #t76 == null ?{core::int?} null : let final core::int #t77 = 0 in self::Extension|[](#t76{self::Class2}, #t77) == null ?{core::int?} self::Extension|[]=(#t76{self::Class2}, #t77, 1.{core::num::+}(c1{self::Class1}.{self::Class1::[]}(1){(core::int) → core::int}){(core::num) → core::int}) : null;
   let final self::Class1? #t78 = c1 in #t78 == null ?{core::int?} null : let final self::Class2? #t79 = #t78{self::Class1}.{self::Class1::field}{self::Class2?} in #t79 == null ?{core::int?} null : self::Extension|[](#t79{self::Class2}, 0);
   let final self::Class1? #t80 = c1 in #t80 == null ?{void} null : let final self::Class2? #t81 = #t80{self::Class1}.{self::Class1::field}{self::Class2?} in #t81 == null ?{void} null : self::Extension|[]=(#t81{self::Class2}, 0, 1);
-  let final self::Class1? #t82 = c1 in #t82 == null ?{void} null : let final self::Class2? #t83 = #t82{self::Class1}.{self::Class1::field}{self::Class2?} in #t83 == null ?{void} null : self::Extension|[]=(#t83{self::Class2}, 0, 1.{core::num::+}((let final self::Class2? #t84 = c2 in #t84 == null ?{core::int?} null : self::Extension|[](#t84{self::Class2}, 0)!) as{Unchecked} core::int){(core::num) → core::int});
-  let final self::Class1? #t85 = c1 in #t85 == null ?{core::int?} null : let final self::Class2? #t86 = #t85{self::Class1}.{self::Class1::field}{self::Class2?} in #t86 == null ?{core::int?} null : let final core::int #t87 = 0 in self::Extension|[]=(#t86{self::Class2}, #t87, self::Extension|[](#t86{self::Class2}, #t87).{core::num::+}(1){(core::num) → core::int});
-  let final self::Class1? #t88 = c1 in #t88 == null ?{core::int?} null : let final self::Class2? #t89 = #t88{self::Class1}.{self::Class1::field}{self::Class2?} in #t89 == null ?{core::int?} null : let final core::int #t90 = 0 in self::Extension|[]=(#t89{self::Class2}, #t90, self::Extension|[](#t89{self::Class2}, #t90).{core::num::+}(1.{core::num::+}((let final self::Class2? #t91 = c2 in #t91 == null ?{core::int?} null : self::Extension|[](#t91{self::Class2}, 0)!) as{Unchecked} core::int){(core::num) → core::int}){(core::num) → core::int});
-  let final self::Class1? #t92 = c1 in #t92 == null ?{core::int?} null : let final self::Class2? #t93 = #t92{self::Class1}.{self::Class1::field}{self::Class2?} in #t93 == null ?{core::int?} null : let final core::int #t94 = 0 in let final core::int #t95 = self::Extension|[](#t93{self::Class2}, #t94).{core::num::+}(1){(core::num) → core::int} in let final void #t96 = self::Extension|[]=(#t93{self::Class2}, #t94, #t95) in #t95;
-  let final self::Class1? #t97 = c1 in #t97 == null ?{core::int?} null : let final self::Class2? #t98 = #t97{self::Class1}.{self::Class1::field}{self::Class2?} in #t98 == null ?{core::int?} null : let final core::int #t99 = 0 in self::Extension|[]=(#t98{self::Class2}, #t99, self::Extension|[](#t98{self::Class2}, #t99).{core::num::+}(1){(core::num) → core::int});
-  let final self::Class1? #t100 = c1 in #t100 == null ?{core::int?} null : let final self::Class2? #t101 = #t100{self::Class1}.{self::Class1::field}{self::Class2?} in #t101 == null ?{core::int?} null : let final core::int #t102 = 0 in self::Extension|[](#t101{self::Class2}, #t102) == null ?{core::int?} self::Extension|[]=(#t101{self::Class2}, #t102, 1) : null;
-  let final self::Class1? #t103 = c1 in #t103 == null ?{core::int?} null : let final self::Class2? #t104 = #t103{self::Class1}.{self::Class1::field}{self::Class2?} in #t104 == null ?{core::int?} null : let final core::int #t105 = 0 in self::Extension|[](#t104{self::Class2}, #t105) == null ?{core::int?} self::Extension|[]=(#t104{self::Class2}, #t105, 1.{core::num::+}((let final self::Class2? #t106 = c2 in #t106 == null ?{core::int?} null : self::Extension|[](#t106{self::Class2}, 1)!) as{Unchecked} core::int){(core::num) → core::int}) : null;
+  let final self::Class1? #t82 = c1 in #t82 == null ?{void} null : let final self::Class2? #t83 = #t82{self::Class1}.{self::Class1::field}{self::Class2?} in #t83 == null ?{void} null : self::Extension|[]=(#t83{self::Class2}, 0, 1.{core::num::+}(let core::int? #t84 = let final self::Class2? #t85 = c2 in #t85 == null ?{core::int?} null : self::Extension|[](#t85{self::Class2}, 0)! in #t84 == null ?{core::int} #t84 as core::int : #t84{core::int}){(core::num) → core::int});
+  let final self::Class1? #t86 = c1 in #t86 == null ?{core::int?} null : let final self::Class2? #t87 = #t86{self::Class1}.{self::Class1::field}{self::Class2?} in #t87 == null ?{core::int?} null : let final core::int #t88 = 0 in self::Extension|[]=(#t87{self::Class2}, #t88, self::Extension|[](#t87{self::Class2}, #t88).{core::num::+}(1){(core::num) → core::int});
+  let final self::Class1? #t89 = c1 in #t89 == null ?{core::int?} null : let final self::Class2? #t90 = #t89{self::Class1}.{self::Class1::field}{self::Class2?} in #t90 == null ?{core::int?} null : let final core::int #t91 = 0 in self::Extension|[]=(#t90{self::Class2}, #t91, self::Extension|[](#t90{self::Class2}, #t91).{core::num::+}(1.{core::num::+}(let core::int? #t92 = let final self::Class2? #t93 = c2 in #t93 == null ?{core::int?} null : self::Extension|[](#t93{self::Class2}, 0)! in #t92 == null ?{core::int} #t92 as core::int : #t92{core::int}){(core::num) → core::int}){(core::num) → core::int});
+  let final self::Class1? #t94 = c1 in #t94 == null ?{core::int?} null : let final self::Class2? #t95 = #t94{self::Class1}.{self::Class1::field}{self::Class2?} in #t95 == null ?{core::int?} null : let final core::int #t96 = 0 in let final core::int #t97 = self::Extension|[](#t95{self::Class2}, #t96).{core::num::+}(1){(core::num) → core::int} in let final void #t98 = self::Extension|[]=(#t95{self::Class2}, #t96, #t97) in #t97;
+  let final self::Class1? #t99 = c1 in #t99 == null ?{core::int?} null : let final self::Class2? #t100 = #t99{self::Class1}.{self::Class1::field}{self::Class2?} in #t100 == null ?{core::int?} null : let final core::int #t101 = 0 in self::Extension|[]=(#t100{self::Class2}, #t101, self::Extension|[](#t100{self::Class2}, #t101).{core::num::+}(1){(core::num) → core::int});
+  let final self::Class1? #t102 = c1 in #t102 == null ?{core::int?} null : let final self::Class2? #t103 = #t102{self::Class1}.{self::Class1::field}{self::Class2?} in #t103 == null ?{core::int?} null : let final core::int #t104 = 0 in self::Extension|[](#t103{self::Class2}, #t104) == null ?{core::int?} self::Extension|[]=(#t103{self::Class2}, #t104, 1) : null;
+  let final self::Class1? #t105 = c1 in #t105 == null ?{core::int?} null : let final self::Class2? #t106 = #t105{self::Class1}.{self::Class1::field}{self::Class2?} in #t106 == null ?{core::int?} null : let final core::int #t107 = 0 in self::Extension|[](#t106{self::Class2}, #t107) == null ?{core::int?} self::Extension|[]=(#t106{self::Class2}, #t107, 1.{core::num::+}(let core::int? #t108 = let final self::Class2? #t109 = c2 in #t109 == null ?{core::int?} null : self::Extension|[](#t109{self::Class2}, 1)! in #t108 == null ?{core::int} #t108 as core::int : #t108{core::int}){(core::num) → core::int}) : null;
 }
 
 
@@ -139,4 +139,4 @@ Evaluated: VariableGet @ org-dartlang-testcase:///null_shorting_index.dart:72:25
 Evaluated: VariableGet @ org-dartlang-testcase:///null_shorting_index.dart:72:25 -> IntConstant(0)
 Evaluated: VariableGet @ org-dartlang-testcase:///null_shorting_index.dart:73:25 -> IntConstant(0)
 Evaluated: VariableGet @ org-dartlang-testcase:///null_shorting_index.dart:73:25 -> IntConstant(0)
-Extra constant evaluation: evaluated: 705, effectively constant: 60
+Extra constant evaluation: evaluated: 723, effectively constant: 60
diff --git a/pkg/front_end/testcases/nnbd/redundant_type_casts.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/redundant_type_casts.dart.weak.transformed.expect
index a6538356aa0..41b48fe6886 100644
--- a/pkg/front_end/testcases/nnbd/redundant_type_casts.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/redundant_type_casts.dart.weak.transformed.expect
@@ -8,6 +8,6 @@ class A<T extends core::Object? = dynamic> extends core::Object {
     : super core::Object::•()
     ;
   get current() → self::A::T%
-    return this.{self::A::_current}{self::A::T?} as{Unchecked} self::A::T%;
+    return let self::A::T? #t1 = this.{self::A::_current}{self::A::T?} in #t1 == null ?{self::A::T%} #t1 as self::A::T% : #t1{self::A::T%};
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/return_null.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/return_null.dart.weak.transformed.expect
index 92f91a018a2..977c16b6fdf 100644
--- a/pkg/front_end/testcases/nnbd/return_null.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/return_null.dart.weak.transformed.expect
@@ -79,14 +79,14 @@ static method returnExplicit() → core::String {
   core::print("foo");
   return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:13:10: Error: The value 'null' can't be returned from a function with return type 'String' because 'String' is not nullable.
   return null; // error
-         ^" in null as{TypeError,Unchecked} core::String;
+         ^" in let Null #t1 = null in #t1 == null ?{core::String} #t1 as{TypeError} core::String : #t1{core::String};
 }
 static method returnMixed(core::bool b) → core::String {
   if(b) {
     core::print("foo");
     return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:19:12: Error: The value 'null' can't be returned from a function with return type 'String' because 'String' is not nullable.
     return null; // error
-           ^" in null as{TypeError,Unchecked} core::String;
+           ^" in let Null #t2 = null in #t2 == null ?{core::String} #t2 as{TypeError} core::String : #t2{core::String};
   }
   return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:16:8: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
 String returnMixed(bool b) /*error*/ {
@@ -153,14 +153,14 @@ static method localFunctions() → dynamic {
     core::print("foo");
     return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:69:12: Error: The value 'null' can't be returned from a function with return type 'String' because 'String' is not nullable.
     return null; // error
-           ^" in null as{TypeError,Unchecked} core::String;
+           ^" in let Null #t3 = null in #t3 == null ?{core::String} #t3 as{TypeError} core::String : #t3{core::String};
   }
   function returnMixed(core::bool b) → core::String {
     if(b) {
       core::print("foo");
       return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:75:14: Error: The value 'null' can't be returned from a function with return type 'String' because 'String' is not nullable.
       return null; // error
-             ^" in null as{TypeError,Unchecked} core::String;
+             ^" in let Null #t4 = null in #t4 == null ?{core::String} #t4 as{TypeError} core::String : #t4{core::String};
     }
     return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:72:3: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
   String returnMixed(bool b) /* error */ {
diff --git a/pkg/front_end/testcases/nnbd/type_constraint_solving_closures_in_upper_and_lower_bounds.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/type_constraint_solving_closures_in_upper_and_lower_bounds.dart.weak.transformed.expect
index 9a05328ee25..e33ba05b737 100644
--- a/pkg/front_end/testcases/nnbd/type_constraint_solving_closures_in_upper_and_lower_bounds.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/type_constraint_solving_closures_in_upper_and_lower_bounds.dart.weak.transformed.expect
@@ -15,7 +15,7 @@ class C<X extends core::Object? = dynamic> extends core::Object {
     ;
 }
 static method check<T extends core::Object? = dynamic>(self::C<core::List<self::check::T%>> f) → self::check::T% {
-  return null as{Unchecked} self::check::T%;
+  return let Null #t1 = null in #t1 == null ?{self::check::T%} #t1 as self::check::T% : #t1{self::check::T%};
 }
 static method test() → void {
   core::int x = self::check<core::int>(new self::C::•<core::List<core::int>>((core::List<core::int> x) → void {}));
@@ -24,3 +24,10 @@ static method test() → void {
              ^" in x as{TypeError} core::String;
 }
 static method main() → dynamic {}
+
+
+Extra constant evaluation status:
+Evaluated: EqualsNull @ org-dartlang-testcase:///type_constraint_solving_closures_in_upper_and_lower_bounds.dart:10:3 -> BoolConstant(true)
+Evaluated: VariableGet @ org-dartlang-testcase:///type_constraint_solving_closures_in_upper_and_lower_bounds.dart:10:15 -> NullConstant(null)
+Evaluated: VariableGet @ org-dartlang-testcase:///type_constraint_solving_closures_in_upper_and_lower_bounds.dart:10:3 -> NullConstant(null)
+Extra constant evaluation: evaluated: 9, effectively constant: 3
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart.weak.transformed.expect
index 7b3dd892c71..6492c5606a7 100644
--- a/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart.weak.transformed.expect
@@ -150,7 +150,7 @@ Try removing the extra positional arguments.
     i = super.{in_2::SuperQ::nullabilityGetter};
     this.{self::ClassQ::nullabilitySetter} = invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:52:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
     nullabilitySetter = null; // error
-                        ^" in null as{TypeError,Unchecked} core::int;
+                        ^" in let Null #t1 = null in #t1 == null ?{core::int} #t1 as{TypeError} core::int : #t1{core::int};
     super.{in_2::SuperQ::nullabilitySetter} = null;
   }
   abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart.weak.transformed.expect
index 5fa6986a975..d73b7e86d6b 100644
--- a/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart.weak.transformed.expect
@@ -128,7 +128,7 @@ Try removing the extra positional arguments.
     i = super.{in_2::SuperQ::nullabilityGetter};
     this.{self::ClassQ::nullabilitySetter} = invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:52:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
     nullabilitySetter = null; // error
-                        ^" in null as{TypeError,Unchecked} core::int;
+                        ^" in let Null #t1 = null in #t1 == null ?{core::int} #t1 as{TypeError} core::int : #t1{core::int};
     super.{in_2::SuperQ::nullabilitySetter} = null;
   }
   abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
@@ -193,7 +193,7 @@ Try removing the extra positional arguments.
     i = super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilityGetter};
     this.{self::ClassMixedInQ::nullabilitySetter} = invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:102:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
     nullabilitySetter = null; // error
-                        ^" in null as{TypeError,Unchecked} core::int;
+                        ^" in let Null #t2 = null in #t2 == null ?{core::int} #t2 as{TypeError} core::int : #t2{core::int};
     super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilitySetter} = null;
   }
   abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart.weak.transformed.expect
index c83d872b993..b7917bf3405 100644
--- a/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart.weak.transformed.expect
@@ -126,7 +126,7 @@ class ClassQ extends in_::LegacyClassQ implements in_2::Super {
     core::int i;
     this.{self::ClassQ::nullabilityMethod}(invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:38:23: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
     nullabilityMethod(null); // error
-                      ^" in null as{TypeError,Unchecked} core::int){(core::int) → core::int};
+                      ^" in let Null #t1 = null in #t1 == null ?{core::int} #t1 as{TypeError} core::int : #t1{core::int}){(core::int) → core::int};
     i = super.{in_2::SuperQ::nullabilityMethod}(null);
     i = this.{in_::LegacyClassQ::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
     i = super.{in_2::SuperQ::optionalArgumentsMethod}(null);
@@ -138,7 +138,7 @@ Try removing the extra positional arguments.
     i = super.{in_2::SuperQ::nullabilityGetter};
     this.{self::ClassQ::nullabilitySetter} = invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:52:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
     nullabilitySetter = null; // error
-                        ^" in null as{TypeError,Unchecked} core::int;
+                        ^" in let Null #t2 = null in #t2 == null ?{core::int} #t2 as{TypeError} core::int : #t2{core::int};
     super.{in_2::SuperQ::nullabilitySetter} = null;
   }
   abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
@@ -194,7 +194,7 @@ class ClassMixedInQ extends in_::LegacyMixedInQ implements in_2::Super {
     core::int i;
     this.{self::ClassMixedInQ::nullabilityMethod}(invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:88:23: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
     nullabilityMethod(null); // error
-                      ^" in null as{TypeError,Unchecked} core::int){(core::int) → core::int};
+                      ^" in let Null #t3 = null in #t3 == null ?{core::int} #t3 as{TypeError} core::int : #t3{core::int}){(core::int) → core::int};
     i = super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilityMethod}(null);
     i = this.{in_::LegacyMixedInQ::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
     i = super.{in_::_LegacyMixedInQ&Object&SuperQ::optionalArgumentsMethod}(null);
@@ -206,7 +206,7 @@ Try removing the extra positional arguments.
     i = super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilityGetter};
     this.{self::ClassMixedInQ::nullabilitySetter} = invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:102:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
     nullabilitySetter = null; // error
-                        ^" in null as{TypeError,Unchecked} core::int;
+                        ^" in let Null #t4 = null in #t4 == null ?{core::int} #t4 as{TypeError} core::int : #t4{core::int};
     super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilitySetter} = null;
   }
   abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41657.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/issue41657.dart.weak.transformed.expect
index e662d939b58..270fd055505 100644
--- a/pkg/front_end/testcases/nnbd_mixed/issue41657.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41657.dart.weak.transformed.expect
@@ -6,9 +6,9 @@ static final field core::bool isLegacySubtyping1a = #C1 is core::List<core::int>
 static const field core::bool isLegacySubtyping1b = #C2;
 static final field core::bool isLegacySubtyping2a = #C3 is core::List<core::int>;
 static const field core::bool isLegacySubtyping2b = #C2;
-static final field core::List<core::int> assertLegacySubtyping1a = #C1 as{Unchecked} core::List<core::int>;
+static final field core::List<core::int> assertLegacySubtyping1a = #C1 as core::List<core::int>;
 static const field core::List<core::int> assertLegacySubtyping1b = #C1;
-static final field core::List<core::int> assertLegacySubtyping2a = #C3 as{Unchecked} core::List<core::int>;
+static final field core::List<core::int> assertLegacySubtyping2a = #C3 as core::List<core::int>;
 static const field core::List<core::int> assertLegacySubtyping2b = #C3;
 static method main() → void {
   self::expect(self::isLegacySubtyping1a, #C2);
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue42181.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/issue42181.dart.weak.transformed.expect
index db2b011e44d..70618b49503 100644
--- a/pkg/front_end/testcases/nnbd_mixed/issue42181.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/issue42181.dart.weak.transformed.expect
@@ -16,7 +16,7 @@ static method f1(core::int x) → core::int?
 static method test() → void {
   (core::int*) → core::int* f = invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue42181.dart:10:9: Error: The value 'null' can't be assigned to a variable of type 'int Function(int)' because 'int Function(int)' is not nullable.
   F f = null; // Static error
-        ^" in null as{TypeError,Unchecked} (core::int*) → core::int*;
+        ^" in let Null #t1 = null in #t1 == null ?{(core::int*) → core::int*} #t1 as{TypeError} (core::int*) → core::int* : #t1{(core::int*) → core::int*};
   f = #C1;
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/main.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/main.dart.weak.transformed.expect
index 12703a06a9e..65180f92e9c 100644
--- a/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/main.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/main.dart.weak.transformed.expect
@@ -35,13 +35,13 @@ static method test() → dynamic {
   core::int i = sub.{opt::_SubClass&Class&Mixin::classMethod}(null){(core::int*) →* core::int*};
   core::int j = invalid-expression "pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/test_lib.dart:10:15: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
   int j = sub.mixinMethod(null);
-              ^" in sub.{opt::_SubClass&Class&Mixin::mixinMethod}(invalid-expression "pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/test_lib.dart:10:27: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
+              ^" in let core::int? #t1 = sub.{opt::_SubClass&Class&Mixin::mixinMethod}(invalid-expression "pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/test_lib.dart:10:27: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
   int j = sub.mixinMethod(null);
-                          ^" in null as{TypeError,Unchecked} core::int){(core::int) →* core::int?} as{TypeError,Unchecked} core::int;
+                          ^" in let Null #t2 = null in #t2 == null ?{core::int} #t2 as{TypeError} core::int : #t2{core::int}){(core::int) →* core::int?} in #t1 == null ?{core::int} #t1 as{TypeError} core::int : #t1{core::int};
   sub.{opt::_SubClass&Class&Mixin::classField2} = sub.{opt::_SubClass&Class&Mixin::classField1}{core::int*};
   sub.{opt::_SubClass&Class&Mixin::mixinField2} = invalid-expression "pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/test_lib.dart:12:25: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
   sub.mixinField2 = sub.mixinField1;
-                        ^" in sub.{opt::_SubClass&Class&Mixin::mixinField1}{core::int?} as{TypeError,Unchecked} core::int;
+                        ^" in let core::int? #t3 = sub.{opt::_SubClass&Class&Mixin::mixinField1}{core::int?} in #t3 == null ?{core::int} #t3 as{TypeError} core::int : #t3{core::int};
 }
 
 library;
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart.weak.transformed.expect b/pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart.weak.transformed.expect
index 65212b37987..1c442cb5e75 100644
--- a/pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart.weak.transformed.expect
@@ -24,12 +24,12 @@ static method test() → dynamic {
   FutureOr<() → opt::A*>foLegacyNonNullable = invalid-expression "pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart:13:42: Error: The value 'null' can't be assigned to a variable of type 'FutureOr<A Function()>' because 'FutureOr<A Function()>' is not nullable.
  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue41501_lib.dart'.
   FutureOr<AAlias> foLegacyNonNullable = null; // error
-                                         ^" in null as{TypeError,Unchecked} FutureOr<() → opt::A*>;
+                                         ^" in let Null #t1 = null in #t1 == null ?{FutureOr<() → opt::A*>} #t1 as{TypeError} FutureOr<() → opt::A*> : #t1{FutureOr<() → opt::A*>};
   has-declared-initializer FutureOr<() →? opt::A*>foLegacyNullable = null;
   FutureOr<opt::A>foNonNullable = invalid-expression "pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart:15:47: Error: The value 'null' can't be assigned to a variable of type 'FutureOr<A>' because 'FutureOr<A>' is not nullable.
  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue41501_lib.dart'.
   FutureOr<AAliasNonNullable> foNonNullable = null; // error
-                                              ^" in null as{TypeError,Unchecked} FutureOr<opt::A>;
+                                              ^" in let Null #t2 = null in #t2 == null ?{FutureOr<opt::A>} #t2 as{TypeError} FutureOr<opt::A> : #t2{FutureOr<opt::A>};
   has-declared-initializer FutureOr<opt::A?>foNullable = null;
   has-declared-initializer FutureOr<opt::A?>foNonNullableNullable = null;
   has-declared-initializer FutureOr<opt::A?>foNullableNullable = null;
diff --git a/pkg/front_end/testcases/patterns/access_order.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/access_order.dart.weak.transformed.expect
index e9c7f35610f..d1c026ea87f 100644
--- a/pkg/front_end/testcases/patterns/access_order.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/access_order.dart.weak.transformed.expect
@@ -322,7 +322,7 @@ abstract class _MyList&Object&ListMixin<E extends core::Object? = dynamic> exten
     }
   }
   method /* from org-dartlang-sdk:///sdk/lib/collection/list.dart */ fillRange(core::int start, core::int end, [covariant-by-class self::_MyList&Object&ListMixin::E? fill = #C2]) → void {
-    self::_MyList&Object&ListMixin::E% value = let self::_MyList&Object&ListMixin::E? #t6 = fill in #t6 == null ?{self::_MyList&Object&ListMixin::E%} #t6 as{Unchecked} self::_MyList&Object&ListMixin::E% : #t6{self::_MyList&Object&ListMixin::E%};
+    self::_MyList&Object&ListMixin::E% value = let self::_MyList&Object&ListMixin::E? #t6 = fill in #t6 == null ?{self::_MyList&Object&ListMixin::E%} let self::_MyList&Object&ListMixin::E? #t7 = #t6 in #t7 == null ?{self::_MyList&Object&ListMixin::E%} #t7 as self::_MyList&Object&ListMixin::E% : #t7{self::_MyList&Object&ListMixin::E%} : #t6{self::_MyList&Object&ListMixin::E%};
     core::RangeError::checkValidRange(start, end, this.{core::List::length}{core::int});
     for (core::int i = start; i.{core::num::<}(end){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
       this.{core::List::[]=}(i, value){(core::int, self::_MyList&Object&ListMixin::E%) → void};
@@ -496,7 +496,7 @@ abstract class _MyList&Object&ListMixin<E extends core::Object? = dynamic> exten
         for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
           self::_MyList&Object&ListMixin::E% element = :sync-for-iterator.{core::Iterator::current}{self::_MyList&Object&ListMixin::E%};
           {
-            this.{core::List::[]=}(let final core::int #t7 = index in let final core::int #t8 = index = #t7.{core::num::+}(1){(core::num) → core::int} in #t7, element){(core::int, self::_MyList&Object&ListMixin::E%) → void};
+            this.{core::List::[]=}(let final core::int #t8 = index in let final core::int #t9 = index = #t8.{core::num::+}(1){(core::num) → core::int} in #t8, element){(core::int, self::_MyList&Object&ListMixin::E%) → void};
           }
         }
       }
@@ -538,31 +538,31 @@ class MyList<E extends core::Object? = dynamic> extends self::_MyList&Object&Lis
 }
 static method test1(core::Object o) → core::String
   return block {
-    core::String #t9;
+    core::String #t10;
     final synthesized core::Object #0#0 = o;
     #L1:
     {
       {
         hoisted core::Object? x;
         hoisted core::Object? y;
-        if(#0#0 is core::List<core::Object?> && #0#0{core::List<core::Object?>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C8 && (let final core::Object? #t10 = x = #0#0{core::List<core::Object?>}.{core::List::[]}(0){(core::int) → core::Object?} in true) && #C9 =={core::num::==}{(core::Object) → core::bool} #0#0{core::List<core::Object?>}.{core::List::[]}(1){(core::int) → core::Object?}) {
+        if(#0#0 is core::List<core::Object?> && #0#0{core::List<core::Object?>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C8 && (let final core::Object? #t11 = x = #0#0{core::List<core::Object?>}.{core::List::[]}(0){(core::int) → core::Object?} in true) && #C9 =={core::num::==}{(core::Object) → core::bool} #0#0{core::List<core::Object?>}.{core::List::[]}(1){(core::int) → core::Object?}) {
           y = #0#0{core::List<core::Object?>}.{core::List::[]}(2){(core::int) → core::Object?};
-          #t9 = "match-1";
+          #t10 = "match-1";
           break #L1;
         }
       }
       {
         if(true) {
-          #t9 = "no match";
+          #t10 = "no match";
           break #L1;
         }
       }
       throw{for-error-handling} new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable type.");
     }
-  } =>#t9;
+  } =>#t10;
 static method test2(core::Object o) → core::String
   return block {
-    core::String #t11;
+    core::String #t12;
     final synthesized core::Object #0#0 = o;
     #L2:
     {
@@ -572,22 +572,22 @@ static method test2(core::Object o) → core::String
         if(#0#0 is core::List<core::Object?> && #0#0{core::List<core::Object?>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C8 && #C10 =={core::num::==}{(core::Object) → core::bool} #0#0{core::List<core::Object?>}.{core::List::[]}(0){(core::int) → core::Object?}) {
           x = #0#0{core::List<core::Object?>}.{core::List::[]}(1){(core::int) → core::Object?};
           y = #0#0{core::List<core::Object?>}.{core::List::[]}(2){(core::int) → core::Object?};
-          #t11 = "match-1";
+          #t12 = "match-1";
           break #L2;
         }
       }
       {
         if(true) {
-          #t11 = "no match";
+          #t12 = "no match";
           break #L2;
         }
       }
       throw{for-error-handling} new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable type.");
     }
-  } =>#t11;
+  } =>#t12;
 static method test3(core::Object o) → core::String
   return block {
-    core::String #t12;
+    core::String #t13;
     final synthesized core::Object #0#0 = o;
     synthesized core::bool #0#4;
     synthesized core::bool #0#4#isSet = false;
@@ -599,29 +599,29 @@ static method test3(core::Object o) → core::String
     {
       {
         hoisted core::Object x;
-        if(#0#0 is core::List<core::Object?> && (#0#4#isSet ?{core::bool} #0#4{core::bool} : let final core::bool #t13 = #0#4#isSet = true in #0#4 = #0#0{core::List<core::Object?>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C9) && (let final core::Object? #t14 = (#0#6#isSet ?{core::Object?} #0#6{core::Object?} : let final core::bool #t15 = #0#6#isSet = true in #0#6 = #0#0{core::List<core::Object?>}.{core::List::[]}(0){(core::int) → core::Object?})! in let final core::Object? #t16 = x = (#0#6#isSet ?{core::Object?} #0#6{core::Object?} : let final core::bool #t17 = #0#6#isSet = true in #0#6 = #0#0{core::List<core::Object?>}.{core::List::[]}(0){(core::int) → core::Object?})! in true) && #C10 =={core::num::==}{(core::Object) → core::bool} (#0#8#isSet ?{core::Object?} #0#8{core::Object?} : let final core::bool #t18 = #0#8#isSet = true in #0#8 = #0#0{core::List<core::Object?>}.{core::List::[]}(1){(core::int) → core::Object?})) {
-          #t12 = "match-1";
+        if(#0#0 is core::List<core::Object?> && (#0#4#isSet ?{core::bool} #0#4{core::bool} : let final core::bool #t14 = #0#4#isSet = true in #0#4 = #0#0{core::List<core::Object?>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C9) && (let final core::Object? #t15 = (#0#6#isSet ?{core::Object?} #0#6{core::Object?} : let final core::bool #t16 = #0#6#isSet = true in #0#6 = #0#0{core::List<core::Object?>}.{core::List::[]}(0){(core::int) → core::Object?})! in let final core::Object? #t17 = x = (#0#6#isSet ?{core::Object?} #0#6{core::Object?} : let final core::bool #t18 = #0#6#isSet = true in #0#6 = #0#0{core::List<core::Object?>}.{core::List::[]}(0){(core::int) → core::Object?})! in true) && #C10 =={core::num::==}{(core::Object) → core::bool} (#0#8#isSet ?{core::Object?} #0#8{core::Object?} : let final core::bool #t19 = #0#8#isSet = true in #0#8 = #0#0{core::List<core::Object?>}.{core::List::[]}(1){(core::int) → core::Object?})) {
+          #t13 = "match-1";
           break #L3;
         }
       }
       {
         hoisted core::Object x;
-        if(#0#0 is core::List<core::Object?> && (#0#4#isSet ?{core::bool} #0#4{core::bool} : let final core::bool #t19 = #0#4#isSet = true in #0#4 = #0#0{core::List<core::Object?>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C9) && #C10 =={core::num::==}{(core::Object) → core::bool} (#0#6#isSet ?{core::Object?} #0#6{core::Object?} : let final core::bool #t20 = #0#6#isSet = true in #0#6 = #0#0{core::List<core::Object?>}.{core::List::[]}(0){(core::int) → core::Object?})) {
-          (#0#8#isSet ?{core::Object?} #0#8{core::Object?} : let final core::bool #t21 = #0#8#isSet = true in #0#8 = #0#0{core::List<core::Object?>}.{core::List::[]}(1){(core::int) → core::Object?})!;
-          x = (#0#8#isSet ?{core::Object?} #0#8{core::Object?} : let final core::bool #t22 = #0#8#isSet = true in #0#8 = #0#0{core::List<core::Object?>}.{core::List::[]}(1){(core::int) → core::Object?})!;
-          #t12 = "match-2";
+        if(#0#0 is core::List<core::Object?> && (#0#4#isSet ?{core::bool} #0#4{core::bool} : let final core::bool #t20 = #0#4#isSet = true in #0#4 = #0#0{core::List<core::Object?>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C9) && #C10 =={core::num::==}{(core::Object) → core::bool} (#0#6#isSet ?{core::Object?} #0#6{core::Object?} : let final core::bool #t21 = #0#6#isSet = true in #0#6 = #0#0{core::List<core::Object?>}.{core::List::[]}(0){(core::int) → core::Object?})) {
+          (#0#8#isSet ?{core::Object?} #0#8{core::Object?} : let final core::bool #t22 = #0#8#isSet = true in #0#8 = #0#0{core::List<core::Object?>}.{core::List::[]}(1){(core::int) → core::Object?})!;
+          x = (#0#8#isSet ?{core::Object?} #0#8{core::Object?} : let final core::bool #t23 = #0#8#isSet = true in #0#8 = #0#0{core::List<core::Object?>}.{core::List::[]}(1){(core::int) → core::Object?})!;
+          #t13 = "match-2";
           break #L3;
         }
       }
       {
         if(true) {
-          #t12 = "no match";
+          #t13 = "no match";
           break #L3;
         }
       }
       throw{for-error-handling} new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable type.");
     }
-  } =>#t12;
+  } =>#t13;
 static method main() → dynamic {
   final self::MyList<core::int> ml1 = new self::MyList::•<core::int>(core::_GrowableList::_literal3<core::int>(1, 2, 3));
   self::expect("match-1", self::test1(ml1));
@@ -656,4 +656,4 @@ Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart
 Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart:462:12 -> IntConstant(-1)
 Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart:471:12 -> IntConstant(-1)
 Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart:480:12 -> IntConstant(-1)
-Extra constant evaluation: evaluated: 1239, effectively constant: 4
+Extra constant evaluation: evaluated: 1245, effectively constant: 4
diff --git a/pkg/front_end/testcases/patterns/boolean_literal_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/boolean_literal_inside_cast.dart.weak.transformed.expect
index 9fe0b400d7f..65b14008bc9 100644
--- a/pkg/front_end/testcases/patterns/boolean_literal_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/boolean_literal_inside_cast.dart.weak.transformed.expect
@@ -7,7 +7,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in #C1 =={core::Object::==}{(core::Object) → core::bool} #0#0 as{Unchecked} core::Object) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in #C1 =={core::Object::==}{(core::Object) → core::bool} (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object})) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/cache_lookups.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/cache_lookups.dart.weak.transformed.expect
index 8011b97b396..7a76db64d05 100644
--- a/pkg/front_end/testcases/patterns/cache_lookups.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/cache_lookups.dart.weak.transformed.expect
@@ -389,7 +389,7 @@ abstract class _CustomList&Object&ListMixin<E extends core::Object? = dynamic> e
     }
   }
   method /* from org-dartlang-sdk:///sdk/lib/collection/list.dart */ fillRange(core::int start, core::int end, [covariant-by-class cac::_CustomList&Object&ListMixin::E? fill = #C5]) → void {
-    cac::_CustomList&Object&ListMixin::E% value = let cac::_CustomList&Object&ListMixin::E? #t18 = fill in #t18 == null ?{cac::_CustomList&Object&ListMixin::E%} #t18 as{Unchecked} cac::_CustomList&Object&ListMixin::E% : #t18{cac::_CustomList&Object&ListMixin::E%};
+    cac::_CustomList&Object&ListMixin::E% value = let cac::_CustomList&Object&ListMixin::E? #t18 = fill in #t18 == null ?{cac::_CustomList&Object&ListMixin::E%} let cac::_CustomList&Object&ListMixin::E? #t19 = #t18 in #t19 == null ?{cac::_CustomList&Object&ListMixin::E%} #t19 as cac::_CustomList&Object&ListMixin::E% : #t19{cac::_CustomList&Object&ListMixin::E%} : #t18{cac::_CustomList&Object&ListMixin::E%};
     core::RangeError::checkValidRange(start, end, this.{core::List::length}{core::int});
     for (core::int i = start; i.{core::num::<}(end){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
       this.{core::List::[]=}(i, value){(core::int, cac::_CustomList&Object&ListMixin::E%) → void};
@@ -563,7 +563,7 @@ abstract class _CustomList&Object&ListMixin<E extends core::Object? = dynamic> e
         for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
           cac::_CustomList&Object&ListMixin::E% element = :sync-for-iterator.{core::Iterator::current}{cac::_CustomList&Object&ListMixin::E%};
           {
-            this.{core::List::[]=}(let final core::int #t19 = index in let final core::int #t20 = index = #t19.{core::num::+}(1){(core::num) → core::int} in #t19, element){(core::int, cac::_CustomList&Object&ListMixin::E%) → void};
+            this.{core::List::[]=}(let final core::int #t20 = index in let final core::int #t21 = index = #t20.{core::num::+}(1){(core::num) → core::int} in #t20, element){(core::int, cac::_CustomList&Object&ListMixin::E%) → void};
           }
         }
       }
@@ -615,4 +615,4 @@ Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart
 Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart:462:12 -> IntConstant(-1)
 Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart:471:12 -> IntConstant(-1)
 Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart:480:12 -> IntConstant(-1)
-Extra constant evaluation: evaluated: 1209, effectively constant: 4
+Extra constant evaluation: evaluated: 1215, effectively constant: 4
diff --git a/pkg/front_end/testcases/patterns/caching.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/caching.dart.weak.transformed.expect
index 6eda0848edf..d3389ccc727 100644
--- a/pkg/front_end/testcases/patterns/caching.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/caching.dart.weak.transformed.expect
@@ -138,7 +138,7 @@ static method ifCase(dynamic o) → core::int {
   }
   {
     final synthesized dynamic #17#0 = o;
-    if(#17#0 is core::Map<core::int, core::int> && #17#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (#17#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} as{Unchecked} core::int).{core::num::>=}(#C11){(core::num) → core::bool}) {
+    if(#17#0 is core::Map<core::int, core::int> && #17#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (let core::int? #t42 = #17#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} in #t42 == null ?{core::int} #t42 as{Unchecked} core::int : #t42{core::int}).{core::num::>=}(#C11){(core::num) → core::bool}) {
       return 18;
     }
   }
@@ -190,8 +190,8 @@ static method ifCase(dynamic o) → core::int {
     synthesized core::bool #24#4#isSet = false;
     {
       hoisted core::int b;
-      if(#24#0 is core::Map<dynamic, dynamic> && #24#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t42 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int) {
-        b = (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t43 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int;
+      if(#24#0 is core::Map<dynamic, dynamic> && #24#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t43 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int) {
+        b = (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t44 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int;
         {
           return 25;
         }
@@ -220,7 +220,7 @@ static method ifCase(dynamic o) → core::int {
     final synthesized dynamic #27#0 = o;
     {
       hoisted dynamic d;
-      if(#27#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #27#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t44 = d = #27#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
+      if(#27#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #27#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t45 = d = #27#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
         return 28;
       }
     }
@@ -238,7 +238,7 @@ static method ifCaseElse(dynamic o) → core::int {
       final synthesized dynamic #1#0 = o;
       synthesized core::Object? #1#2;
       synthesized core::bool #1#2#isSet = false;
-      if(#1#0 is ({f: core::Object?}) && ((let final core::int #t45 = (#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t46 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t47 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::>=}(#C2){(core::num) → core::bool}) && (let final core::int #t48 = (#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t49 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t50 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::<}(#C3){(core::num) → core::bool}))) {
+      if(#1#0 is ({f: core::Object?}) && ((let final core::int #t46 = (#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t47 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t48 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::>=}(#C2){(core::num) → core::bool}) && (let final core::int #t49 = (#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t50 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t51 = #1#2#isSet = true in #1#2 = #1#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::<}(#C3){(core::num) → core::bool}))) {
         return 2;
       }
       else {
@@ -250,12 +250,12 @@ static method ifCaseElse(dynamic o) → core::int {
           final synthesized dynamic #3#0 = o;
           synthesized core::Object? #3#2;
           synthesized core::bool #3#2#isSet = false;
-          if(#3#0 is ({g: core::Object?}) && (let final core::int #t51 = (#3#2#isSet ?{core::Object?} #3#2{core::Object?} : let final core::bool #t52 = #3#2#isSet = true in #3#2 = #3#0{({g: core::Object?})}.g{core::Object?}) as core::int in #C6 =={core::num::==}{(core::Object) → core::bool} (#3#2#isSet ?{core::Object?} #3#2{core::Object?} : let final core::bool #t53 = #3#2#isSet = true in #3#2 = #3#0{({g: core::Object?})}.g{core::Object?}) as core::int)) {
+          if(#3#0 is ({g: core::Object?}) && (let final core::int #t52 = (#3#2#isSet ?{core::Object?} #3#2{core::Object?} : let final core::bool #t53 = #3#2#isSet = true in #3#2 = #3#0{({g: core::Object?})}.g{core::Object?}) as core::int in #C6 =={core::num::==}{(core::Object) → core::bool} (#3#2#isSet ?{core::Object?} #3#2{core::Object?} : let final core::bool #t54 = #3#2#isSet = true in #3#2 = #3#0{({g: core::Object?})}.g{core::Object?}) as core::int)) {
             return 4;
           }
           else {
             final synthesized dynamic #4#0 = o;
-            if(#4#0 is ({a: core::Object?}) && (let final core::Object? #t54 = #4#0{({a: core::Object?})}.a{core::Object?}! in true)) {
+            if(#4#0 is ({a: core::Object?}) && (let final core::Object? #t55 = #4#0{({a: core::Object?})}.a{core::Object?}! in true)) {
               return 5;
             }
             else {
@@ -277,7 +277,7 @@ static method ifCaseElse(dynamic o) → core::int {
                     final synthesized dynamic #8#0 = o;
                     synthesized core::int #8#2;
                     synthesized core::bool #8#2#isSet = false;
-                    if(#8#0 is core::List<dynamic> && (#8#2#isSet ?{core::int} #8#2{core::int} : let final core::bool #t55 = #8#2#isSet = true in #8#2 = #8#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool} && #C2 =={core::num::==}{(core::Object) → core::bool} #8#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} && #C8 =={core::num::==}{(core::Object) → core::bool} #8#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic} && #C3 =={core::num::==}{(core::Object) → core::bool} #8#0{core::List<dynamic>}.{core::List::[]}((#8#2#isSet ?{core::int} #8#2{core::int} : let final core::bool #t56 = #8#2#isSet = true in #8#2 = #8#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic}) {
+                    if(#8#0 is core::List<dynamic> && (#8#2#isSet ?{core::int} #8#2{core::int} : let final core::bool #t56 = #8#2#isSet = true in #8#2 = #8#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool} && #C2 =={core::num::==}{(core::Object) → core::bool} #8#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} && #C8 =={core::num::==}{(core::Object) → core::bool} #8#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic} && #C3 =={core::num::==}{(core::Object) → core::bool} #8#0{core::List<dynamic>}.{core::List::[]}((#8#2#isSet ?{core::int} #8#2{core::int} : let final core::bool #t57 = #8#2#isSet = true in #8#2 = #8#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic}) {
                       return 9;
                     }
                     else {
@@ -288,7 +288,7 @@ static method ifCaseElse(dynamic o) → core::int {
                       synthesized core::bool #9#15#isSet = false;
                       synthesized dynamic #9#19;
                       synthesized core::bool #9#19#isSet = false;
-                      if(#9#0 is core::List<dynamic> && #9#0{core::List<dynamic>}.{core::List::length}{core::int}.{core::num::>=}(#C7){(core::num) → core::bool} && #C8 =={core::num::==}{(core::Object) → core::bool} #9#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} && #C3 =={core::num::==}{(core::Object) → core::bool} #9#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic} && ((#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t57 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t58 = (#9#15#isSet ?{dynamic} #9#15{dynamic} : let final core::bool #t59 = #9#15#isSet = true in #9#15 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t60 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#9#15#isSet ?{dynamic} #9#15{dynamic} : let final core::bool #t61 = #9#15#isSet = true in #9#15 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t62 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t63 = (#9#19#isSet ?{dynamic} #9#19{dynamic} : let final core::bool #t64 = #9#19#isSet = true in #9#19 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t65 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#9#19#isSet ?{dynamic} #9#19{dynamic} : let final core::bool #t66 = #9#19#isSet = true in #9#19 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t67 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool}))) {
+                      if(#9#0 is core::List<dynamic> && #9#0{core::List<dynamic>}.{core::List::length}{core::int}.{core::num::>=}(#C7){(core::num) → core::bool} && #C8 =={core::num::==}{(core::Object) → core::bool} #9#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} && #C3 =={core::num::==}{(core::Object) → core::bool} #9#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic} && ((#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t58 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t59 = (#9#15#isSet ?{dynamic} #9#15{dynamic} : let final core::bool #t60 = #9#15#isSet = true in #9#15 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t61 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#9#15#isSet ?{dynamic} #9#15{dynamic} : let final core::bool #t62 = #9#15#isSet = true in #9#15 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t63 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t64 = (#9#19#isSet ?{dynamic} #9#19{dynamic} : let final core::bool #t65 = #9#19#isSet = true in #9#19 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t66 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#9#19#isSet ?{dynamic} #9#19{dynamic} : let final core::bool #t67 = #9#19#isSet = true in #9#19 = (#9#12#isSet ?{core::List<dynamic>} #9#12{core::List<dynamic>} : let final core::bool #t68 = #9#12#isSet = true in #9#12 = #9#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool}))) {
                         return 10;
                       }
                       else {
@@ -301,7 +301,7 @@ static method ifCaseElse(dynamic o) → core::int {
                         synthesized core::bool #10#16#isSet = false;
                         synthesized dynamic #10#20;
                         synthesized core::bool #10#20#isSet = false;
-                        if(#10#0 is core::List<dynamic> && (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t68 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool} && #C3 =={core::num::==}{(core::Object) → core::bool} #10#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} && #C4 =={core::num::==}{(core::Object) → core::bool} #10#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic} && ((#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t69 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t70 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t71 = (#10#16#isSet ?{dynamic} #10#16{dynamic} : let final core::bool #t72 = #10#16#isSet = true in #10#16 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t73 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t74 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#10#16#isSet ?{dynamic} #10#16{dynamic} : let final core::bool #t75 = #10#16#isSet = true in #10#16 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t76 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t77 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t78 = (#10#20#isSet ?{dynamic} #10#20{dynamic} : let final core::bool #t79 = #10#20#isSet = true in #10#20 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t80 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t81 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#10#20#isSet ?{dynamic} #10#20{dynamic} : let final core::bool #t82 = #10#20#isSet = true in #10#20 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t83 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t84 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool})) && #C5 =={core::num::==}{(core::Object) → core::bool} #10#0{core::List<dynamic>}.{core::List::[]}((#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t85 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic}) {
+                        if(#10#0 is core::List<dynamic> && (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t69 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool} && #C3 =={core::num::==}{(core::Object) → core::bool} #10#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} && #C4 =={core::num::==}{(core::Object) → core::bool} #10#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic} && ((#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t70 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t71 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t72 = (#10#16#isSet ?{dynamic} #10#16{dynamic} : let final core::bool #t73 = #10#16#isSet = true in #10#16 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t74 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t75 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#10#16#isSet ?{dynamic} #10#16{dynamic} : let final core::bool #t76 = #10#16#isSet = true in #10#16 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t77 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t78 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t79 = (#10#20#isSet ?{dynamic} #10#20{dynamic} : let final core::bool #t80 = #10#20#isSet = true in #10#20 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t81 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t82 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#10#20#isSet ?{dynamic} #10#20{dynamic} : let final core::bool #t83 = #10#20#isSet = true in #10#20 = (#10#12#isSet ?{core::List<dynamic>} #10#12{core::List<dynamic>} : let final core::bool #t84 = #10#12#isSet = true in #10#12 = #10#0{core::List<dynamic>}.{core::List::sublist}(2, (#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t85 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool})) && #C5 =={core::num::==}{(core::Object) → core::bool} #10#0{core::List<dynamic>}.{core::List::[]}((#10#2#isSet ?{core::int} #10#2{core::int} : let final core::bool #t86 = #10#2#isSet = true in #10#2 = #10#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic}) {
                           return 11;
                         }
                         else {
@@ -336,7 +336,7 @@ static method ifCaseElse(dynamic o) → core::int {
                                     }
                                     else {
                                       final synthesized dynamic #17#0 = o;
-                                      if(#17#0 is core::Map<core::int, core::int> && #17#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (#17#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} as{Unchecked} core::int).{core::num::>=}(#C11){(core::num) → core::bool}) {
+                                      if(#17#0 is core::Map<core::int, core::int> && #17#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (let core::int? #t87 = #17#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} in #t87 == null ?{core::int} #t87 as{Unchecked} core::int : #t87{core::int}).{core::num::>=}(#C11){(core::num) → core::bool}) {
                                         return 18;
                                       }
                                       else {
@@ -380,8 +380,8 @@ static method ifCaseElse(dynamic o) → core::int {
                                                       synthesized core::bool #24#4#isSet = false;
                                                       {
                                                         hoisted core::int b;
-                                                        if(#24#0 is core::Map<dynamic, dynamic> && #24#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t86 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int) {
-                                                          b = (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t87 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int;
+                                                        if(#24#0 is core::Map<dynamic, dynamic> && #24#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t88 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int) {
+                                                          b = (#24#4#isSet ?{dynamic} #24#4{dynamic} : let final core::bool #t89 = #24#4#isSet = true in #24#4 = #24#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int;
                                                           {
                                                             return 25;
                                                           }
@@ -405,7 +405,7 @@ static method ifCaseElse(dynamic o) → core::int {
                                                                 final synthesized dynamic #27#0 = o;
                                                                 {
                                                                   hoisted dynamic d;
-                                                                  if(#27#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #27#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t88 = d = #27#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
+                                                                  if(#27#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #27#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t90 = d = #27#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
                                                                     return 28;
                                                                   }
                                                                   else {
@@ -493,7 +493,7 @@ static method switchStatement(dynamic o) → core::int {
       }
     }
     {
-      if(#0#0 is ({f: core::Object?}) && ((let final core::int #t89 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t90 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t91 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::>=}(#C2){(core::num) → core::bool}) && (let final core::int #t92 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t93 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t94 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::<}(#C3){(core::num) → core::bool}))) {
+      if(#0#0 is ({f: core::Object?}) && ((let final core::int #t91 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t92 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t93 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::>=}(#C2){(core::num) → core::bool}) && (let final core::int #t94 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t95 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t96 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::<}(#C3){(core::num) → core::bool}))) {
         {
           return 2;
         }
@@ -507,63 +507,63 @@ static method switchStatement(dynamic o) → core::int {
       }
     }
     {
-      if(#0#0 is ({g: core::Object?}) && (let final core::int #t95 = (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t96 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int in #C6 =={core::num::==}{(core::Object) → core::bool} (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t97 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int)) {
+      if(#0#0 is ({g: core::Object?}) && (let final core::int #t97 = (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t98 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int in #C6 =={core::num::==}{(core::Object) → core::bool} (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t99 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int)) {
         {
           return 4;
         }
       }
     }
     {
-      if(#0#0 is ({a: core::Object?}) && (let final core::Object? #t98 = (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t99 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?})}.a{core::Object?})! in true)) {
+      if(#0#0 is ({a: core::Object?}) && (let final core::Object? #t100 = (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t101 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?})}.a{core::Object?})! in true)) {
         {
           return 5;
         }
       }
     }
     {
-      if(#0#0 is ({b: core::Object?}) && (!((#0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t100 = #0#23#isSet = true in #0#23 = #0#0{({b: core::Object?})}.b{core::Object?}) == null) && true)) {
+      if(#0#0 is ({b: core::Object?}) && (!((#0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t102 = #0#23#isSet = true in #0#23 = #0#0{({b: core::Object?})}.b{core::Object?}) == null) && true)) {
         {
           return 6;
         }
       }
     }
     {
-      if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t101 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C7 && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t102 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t103 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
+      if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t103 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C7 && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t104 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t105 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
         {
           return 7;
         }
       }
     }
     {
-      if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t104 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t105 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t106 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t107 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
+      if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t106 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t107 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t108 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t109 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
         {
           return 8;
         }
       }
     }
     {
-      if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t108 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t109 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t110 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t111 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t112 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t113 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
+      if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t110 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t111 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t112 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t113 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t114 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t115 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
         {
           return 9;
         }
       }
     }
     {
-      if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t114 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t115 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t116 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t117 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t118 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t119 = (#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t120 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t121 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t122 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t123 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t124 = (#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t125 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t126 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t127 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t128 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool}))) {
+      if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t116 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t117 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t118 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t119 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t120 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t121 = (#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t122 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t123 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t124 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t125 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t126 = (#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t127 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t128 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t129 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t130 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool}))) {
         {
           return 10;
         }
       }
     }
     {
-      if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t129 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t130 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t131 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C4 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t132 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t133 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t134 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t135 = (#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t136 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t137 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t138 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t139 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t140 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t141 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t142 = (#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t143 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t144 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t145 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t146 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t147 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t148 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool})) && #C5 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t149 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t150 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
+      if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t131 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t132 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t133 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C4 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t134 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t135 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t136 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t137 = (#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t138 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t139 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t140 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t141 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t142 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t143 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t144 = (#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t145 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t146 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t147 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t148 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t149 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t150 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool})) && #C5 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t151 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t152 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
         {
           return 11;
         }
       }
     }
     {
-      if(#0#0 is self::Class && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t151 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int})) {
+      if(#0#0 is self::Class && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t153 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int})) {
         {
           return 12;
         }
@@ -577,7 +577,7 @@ static method switchStatement(dynamic o) → core::int {
       }
     }
     {
-      if(#0#0 is self::Class && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t152 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int}) && #C8 =={core::num::==}{(core::Object) → core::bool} #0#0{self::Class}.{self::Class::getter}{core::int}) {
+      if(#0#0 is self::Class && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t154 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int}) && #C8 =={core::num::==}{(core::Object) → core::bool} #0#0{self::Class}.{self::Class::getter}{core::int}) {
         {
           return 14;
         }
@@ -605,14 +605,14 @@ static method switchStatement(dynamic o) → core::int {
       }
     }
     {
-      if(#0#0 is core::Map<core::int, core::int> && #0#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (#0#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} as{Unchecked} core::int).{core::num::>=}(#C11){(core::num) → core::bool}) {
+      if(#0#0 is core::Map<core::int, core::int> && #0#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (let core::int? #t155 = #0#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} in #t155 == null ?{core::int} #t155 as{Unchecked} core::int : #t155{core::int}).{core::num::>=}(#C11){(core::num) → core::bool}) {
         {
           return 18;
         }
       }
     }
     {
-      if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t153 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C1) {
+      if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t156 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C1) {
         {
           return 19;
         }
@@ -648,7 +648,7 @@ static method switchStatement(dynamic o) → core::int {
     }
     {
       hoisted dynamic a;
-      if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool} && (let final dynamic #t154 = a = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C7){(core::Object?) → dynamic} in true)) {
+      if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool} && (let final dynamic #t157 = a = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C7){(core::Object?) → dynamic} in true)) {
         {
           return 24;
         }
@@ -656,7 +656,7 @@ static method switchStatement(dynamic o) → core::int {
     }
     {
       hoisted core::int b;
-      if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && ((#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t155 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int && (let final core::int #t156 = b = (#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t157 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int in true))) {
+      if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && ((#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t158 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int && (let final core::int #t159 = b = (#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t160 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int in true))) {
         {
           return 25;
         }
@@ -671,7 +671,7 @@ static method switchStatement(dynamic o) → core::int {
     }
     {
       hoisted dynamic c;
-      if(#0#0 is ({a: core::Object?, b: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t158 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?, b: core::Object?})}.a{core::Object?}) && (let final core::Object? #t159 = c = #0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t160 = #0#23#isSet = true in #0#23 = #0#0{({a: core::Object?, b: core::Object?})}.b{core::Object?} in true)) {
+      if(#0#0 is ({a: core::Object?, b: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t161 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?, b: core::Object?})}.a{core::Object?}) && (let final core::Object? #t162 = c = #0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t163 = #0#23#isSet = true in #0#23 = #0#0{({a: core::Object?, b: core::Object?})}.b{core::Object?} in true)) {
         {
           return 27;
         }
@@ -679,7 +679,7 @@ static method switchStatement(dynamic o) → core::int {
     }
     {
       hoisted dynamic d;
-      if(#0#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #0#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t161 = d = #0#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
+      if(#0#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #0#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t164 = d = #0#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
         {
           return 28;
         }
@@ -697,7 +697,7 @@ static method switchStatement(dynamic o) → core::int {
 static method switchExpression(dynamic o) → core::int {
   core::print("o = ${o}");
   return block {
-    core::int #t162;
+    core::int #t165;
     final synthesized dynamic #0#0 = o;
     synthesized core::Object? #0#4;
     synthesized core::bool #0#4#isSet = false;
@@ -739,139 +739,139 @@ static method switchExpression(dynamic o) → core::int {
     {
       {
         if(#C1 =={core::num::==}{(core::Object) → core::bool} #0#0) {
-          #t162 = 1;
+          #t165 = 1;
           break #L2;
         }
       }
       {
-        if(#0#0 is ({f: core::Object?}) && ((let final core::int #t163 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t164 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t165 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::>=}(#C2){(core::num) → core::bool}) && (let final core::int #t166 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t167 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t168 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::<}(#C3){(core::num) → core::bool}))) {
-          #t162 = 2;
+        if(#0#0 is ({f: core::Object?}) && ((let final core::int #t166 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t167 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t168 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::>=}(#C2){(core::num) → core::bool}) && (let final core::int #t169 = (#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t170 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int in ((#0#4#isSet ?{core::Object?} #0#4{core::Object?} : let final core::bool #t171 = #0#4#isSet = true in #0#4 = #0#0{({f: core::Object?})}.f{core::Object?}) as core::int).{core::num::<}(#C3){(core::num) → core::bool}))) {
+          #t165 = 2;
           break #L2;
         }
       }
       {
         if(#C4 =={core::num::==}{(core::Object) → core::bool} #0#0 || #C5 =={core::num::==}{(core::Object) → core::bool} #0#0) {
-          #t162 = 3;
+          #t165 = 3;
           break #L2;
         }
       }
       {
-        if(#0#0 is ({g: core::Object?}) && (let final core::int #t169 = (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t170 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int in #C6 =={core::num::==}{(core::Object) → core::bool} (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t171 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int)) {
-          #t162 = 4;
+        if(#0#0 is ({g: core::Object?}) && (let final core::int #t172 = (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t173 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int in #C6 =={core::num::==}{(core::Object) → core::bool} (#0#15#isSet ?{core::Object?} #0#15{core::Object?} : let final core::bool #t174 = #0#15#isSet = true in #0#15 = #0#0{({g: core::Object?})}.g{core::Object?}) as core::int)) {
+          #t165 = 4;
           break #L2;
         }
       }
       {
-        if(#0#0 is ({a: core::Object?}) && (let final core::Object? #t172 = (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t173 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?})}.a{core::Object?})! in true)) {
-          #t162 = 5;
+        if(#0#0 is ({a: core::Object?}) && (let final core::Object? #t175 = (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t176 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?})}.a{core::Object?})! in true)) {
+          #t165 = 5;
           break #L2;
         }
       }
       {
-        if(#0#0 is ({b: core::Object?}) && (!((#0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t174 = #0#23#isSet = true in #0#23 = #0#0{({b: core::Object?})}.b{core::Object?}) == null) && true)) {
-          #t162 = 6;
+        if(#0#0 is ({b: core::Object?}) && (!((#0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t177 = #0#23#isSet = true in #0#23 = #0#0{({b: core::Object?})}.b{core::Object?}) == null) && true)) {
+          #t165 = 6;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t175 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C7 && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t176 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t177 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
-          #t162 = 7;
+        if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t178 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C7 && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t179 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t180 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
+          #t165 = 7;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t178 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t179 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t180 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t181 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
-          #t162 = 8;
+        if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t181 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t182 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t183 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t184 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic})) {
+          #t165 = 8;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t182 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t183 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t184 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t185 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t186 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t187 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
-          #t162 = 9;
+        if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t185 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t186 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t187 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t188 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t189 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t190 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
+          #t165 = 9;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t188 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t189 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t190 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t191 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t192 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t193 = (#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t194 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t195 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t196 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t197 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t198 = (#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t199 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t200 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t201 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t202 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool}))) {
-          #t162 = 10;
+        if(#0#0 is core::List<dynamic> && (#0#34#isSet ?{core::bool} #0#34{core::bool} : let final core::bool #t191 = #0#34#isSet = true in #0#34 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t192 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C7){(core::num) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t193 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t194 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t195 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t196 = (#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t197 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t198 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#50#isSet ?{dynamic} #0#50{dynamic} : let final core::bool #t199 = #0#50#isSet = true in #0#50 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t200 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t201 = (#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t202 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t203 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#53#isSet ?{dynamic} #0#53{dynamic} : let final core::bool #t204 = #0#53#isSet = true in #0#53 = (#0#47#isSet ?{core::List<dynamic>} #0#47{core::List<dynamic>} : let final core::bool #t205 = #0#47#isSet = true in #0#47 = #0#0{core::List<dynamic>}.{core::List::sublist}(2){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool}))) {
+          #t165 = 10;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t203 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t204 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t205 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C4 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t206 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t207 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t208 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t209 = (#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t210 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t211 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t212 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t213 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t214 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t215 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t216 = (#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t217 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t218 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t219 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t220 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t221 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t222 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool})) && #C5 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t223 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t224 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
-          #t162 = 11;
+        if(#0#0 is core::List<dynamic> && (#0#38#isSet ?{core::bool} #0#38{core::bool} : let final core::bool #t206 = #0#38#isSet = true in #0#38 = (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t207 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::>=}(#C2){(core::num) → core::bool}) && #C3 =={core::num::==}{(core::Object) → core::bool} (#0#30#isSet ?{dynamic} #0#30{dynamic} : let final core::bool #t208 = #0#30#isSet = true in #0#30 = #0#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) && #C4 =={core::num::==}{(core::Object) → core::bool} (#0#32#isSet ?{dynamic} #0#32{dynamic} : let final core::bool #t209 = #0#32#isSet = true in #0#32 = #0#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) && ((#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t210 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t211 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C7 && (let final core::int #t212 = (#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t213 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t214 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t215 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int in ((#0#61#isSet ?{dynamic} #0#61{dynamic} : let final core::bool #t216 = #0#61#isSet = true in #0#61 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t217 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t218 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(0){(core::int) → dynamic}) as core::int).{core::num::<}(#C1){(core::num) → core::bool}) && (let final core::int #t219 = (#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t220 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t221 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t222 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int in ((#0#64#isSet ?{dynamic} #0#64{dynamic} : let final core::bool #t223 = #0#64#isSet = true in #0#64 = (#0#58#isSet ?{core::List<dynamic>} #0#58{core::List<dynamic>} : let final core::bool #t224 = #0#58#isSet = true in #0#58 = #0#0{core::List<dynamic>}.{core::List::sublist}(2, (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t225 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int, [core::int?]) → core::List<dynamic>}).{core::List::[]}(1){(core::int) → dynamic}) as core::int).{core::num::>}(#C7){(core::num) → core::bool})) && #C5 =={core::num::==}{(core::Object) → core::bool} (#0#43#isSet ?{dynamic} #0#43{dynamic} : let final core::bool #t226 = #0#43#isSet = true in #0#43 = #0#0{core::List<dynamic>}.{core::List::[]}((#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t227 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}).{core::num::-}(1){(core::num) → core::int}){(core::int) → dynamic})) {
+          #t165 = 11;
           break #L2;
         }
       }
       {
-        if(#0#0 is self::Class && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t225 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int})) {
-          #t162 = 12;
+        if(#0#0 is self::Class && #C1 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t228 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int})) {
+          #t165 = 12;
           break #L2;
         }
       }
       {
         if(#0#0 is self::Class && #C7 =={core::num::==}{(core::Object) → core::bool} #0#0{self::Class}.{self::Class::finalField}{core::int}) {
-          #t162 = 13;
+          #t165 = 13;
           break #L2;
         }
       }
       {
-        if(#0#0 is self::Class && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t226 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int}) && #C8 =={core::num::==}{(core::Object) → core::bool} #0#0{self::Class}.{self::Class::getter}{core::int}) {
-          #t162 = 14;
+        if(#0#0 is self::Class && #C2 =={core::num::==}{(core::Object) → core::bool} (#0#69#isSet ?{core::int} #0#69{core::int} : let final core::bool #t229 = #0#69#isSet = true in #0#69 = #0#0{self::Class}.{self::Class::field}{core::int}) && #C8 =={core::num::==}{(core::Object) → core::bool} #0#0{self::Class}.{self::Class::getter}{core::int}) {
+          #t165 = 14;
           break #L2;
         }
       }
       {
         if(#0#0 is self::Class) {
-          #t162 = 15;
+          #t165 = 15;
           break #L2;
         }
       }
       {
         if(#0#0 =={core::Object::==}{(core::Object) → core::bool} #C9) {
-          #t162 = 16;
+          #t165 = 16;
           break #L2;
         }
       }
       {
         if(#0#0 is ({e: core::Object?}) && !(#0#0{({e: core::Object?})}.e{core::Object?} =={core::Object::==}{(core::Object) → core::bool} #C10)) {
-          #t162 = 17;
+          #t165 = 17;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::Map<core::int, core::int> && #0#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (#0#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} as{Unchecked} core::int).{core::num::>=}(#C11){(core::num) → core::bool}) {
-          #t162 = 18;
+        if(#0#0 is core::Map<core::int, core::int> && #0#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && (let core::int? #t230 = #0#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} in #t230 == null ?{core::int} #t230 as{Unchecked} core::int : #t230{core::int}).{core::num::>=}(#C11){(core::num) → core::bool}) {
+          #t165 = 18;
           break #L2;
         }
       }
       {
-        if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t227 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C1) {
-          #t162 = 19;
+        if(#0#0 is core::List<dynamic> && (#0#26#isSet ?{core::int} #0#26{core::int} : let final core::bool #t231 = #0#26#isSet = true in #0#26 = #0#0{core::List<dynamic>}.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C1) {
+          #t165 = 19;
           break #L2;
         }
       }
       {
         if(#0#0 is core::bool) {
-          #t162 = 20;
+          #t165 = 20;
           break #L2;
         }
       }
       {
         if(#0#0 is core::Map<dynamic, dynamic> && o{core::Map<dynamic, dynamic>}.{core::Map::isEmpty}{core::bool}) {
-          #t162 = 21;
+          #t165 = 21;
           break #L2;
         }
       }
       {
         if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C12){(core::Object?) → core::bool} && #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C12){(core::Object?) → dynamic} is core::int) {
-          #t162 = 22;
+          #t165 = 22;
           break #L2;
         }
       }
       {
         if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C1){(core::Object?) → dynamic} is core::String) {
-          #t162 = 23;
+          #t165 = 23;
           break #L2;
         }
       }
@@ -879,48 +879,48 @@ static method switchExpression(dynamic o) → core::int {
         hoisted dynamic a;
         if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool}) {
           a = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C7){(core::Object?) → dynamic};
-          #t162 = 24;
+          #t165 = 24;
           break #L2;
         }
       }
       {
         hoisted core::int b;
-        if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t228 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int) {
-          b = (#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t229 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int;
-          #t162 = 25;
+        if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C2){(core::Object?) → core::bool} && (#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t232 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) is core::int) {
+          b = (#0#98#isSet ?{dynamic} #0#98{dynamic} : let final core::bool #t233 = #0#98#isSet = true in #0#98 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C2){(core::Object?) → dynamic}) as{Unchecked} core::int;
+          #t165 = 25;
           break #L2;
         }
       }
       {
         if(#0#0 is (core::Object?, core::Object?) && #C12 =={core::num::==}{(core::Object) → core::bool} #0#0{(core::Object?, core::Object?)}.$1{core::Object?} && #C1 =={core::num::==}{(core::Object) → core::bool} #0#0{(core::Object?, core::Object?)}.$2{core::Object?}) {
-          #t162 = 26;
+          #t165 = 26;
           break #L2;
         }
       }
       {
         hoisted dynamic c;
-        if(#0#0 is ({a: core::Object?, b: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t230 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?, b: core::Object?})}.a{core::Object?})) {
-          c = #0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t231 = #0#23#isSet = true in #0#23 = #0#0{({a: core::Object?, b: core::Object?})}.b{core::Object?};
-          #t162 = 27;
+        if(#0#0 is ({a: core::Object?, b: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} (#0#20#isSet ?{core::Object?} #0#20{core::Object?} : let final core::bool #t234 = #0#20#isSet = true in #0#20 = #0#0{({a: core::Object?, b: core::Object?})}.a{core::Object?})) {
+          c = #0#23#isSet ?{core::Object?} #0#23{core::Object?} : let final core::bool #t235 = #0#23#isSet = true in #0#23 = #0#0{({a: core::Object?, b: core::Object?})}.b{core::Object?};
+          #t165 = 27;
           break #L2;
         }
       }
       {
         hoisted dynamic d;
-        if(#0#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #0#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t232 = d = #0#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
-          #t162 = 28;
+        if(#0#0 is ({c: core::Object?, d: core::Object?}) && #C12 =={core::num::==}{(core::Object) → core::bool} #0#0{({c: core::Object?, d: core::Object?})}.c{core::Object?} && (let final core::Object? #t236 = d = #0#0{({c: core::Object?, d: core::Object?})}.d{core::Object?} in true) && d is core::int) {
+          #t165 = 28;
           break #L2;
         }
       }
       {
         if(true) {
-          #t162 = 0;
+          #t165 = 0;
           break #L2;
         }
       }
       throw{for-error-handling} new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable type.");
     }
-  } =>#t162;
+  } =>#t165;
 }
 static method test(dynamic expected, dynamic value) → dynamic {
   self::expect(expected, self::ifCase(value));
@@ -1021,4 +1021,4 @@ Evaluated: RecordLiteral @ org-dartlang-testcase:///caching.dart:331:12 -> Recor
 Evaluated: RecordLiteral @ org-dartlang-testcase:///caching.dart:332:12 -> RecordConstant(const ({c: 0, d: 1}))
 Evaluated: RecordLiteral @ org-dartlang-testcase:///caching.dart:333:12 -> RecordConstant(const ({c: 0, d: 2}))
 Evaluated: RecordLiteral @ org-dartlang-testcase:///caching.dart:334:11 -> RecordConstant(const ({c: 0, d: "foo"}))
-Extra constant evaluation: evaluated: 2729, effectively constant: 14
+Extra constant evaluation: evaluated: 2753, effectively constant: 14
diff --git a/pkg/front_end/testcases/patterns/caching_constants.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/caching_constants.dart.weak.transformed.expect
index e5be0012172..6248dc94faf 100644
--- a/pkg/front_end/testcases/patterns/caching_constants.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/caching_constants.dart.weak.transformed.expect
@@ -25,7 +25,7 @@ abstract class _MyMap&Object&MapMixin<K extends core::Object? = dynamic, V exten
       for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
         self::_MyMap&Object&MapMixin::K% key = :sync-for-iterator.{core::Iterator::current}{self::_MyMap&Object&MapMixin::K%};
         {
-          action(key, let self::_MyMap&Object&MapMixin::V? #t1 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t1 == null ?{self::_MyMap&Object&MapMixin::V%} #t1 as{Unchecked} self::_MyMap&Object&MapMixin::V% : #t1{self::_MyMap&Object&MapMixin::V%}){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → void};
+          action(key, let self::_MyMap&Object&MapMixin::V? #t1 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t1 == null ?{self::_MyMap&Object&MapMixin::V%} let self::_MyMap&Object&MapMixin::V? #t2 = #t1 in #t2 == null ?{self::_MyMap&Object&MapMixin::V%} #t2 as self::_MyMap&Object&MapMixin::V% : #t2{self::_MyMap&Object&MapMixin::V%} : #t1{self::_MyMap&Object&MapMixin::V%}){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → void};
         }
       }
     }
@@ -50,16 +50,16 @@ abstract class _MyMap&Object&MapMixin<K extends core::Object? = dynamic, V exten
   }
   method /* from org-dartlang-sdk:///sdk/lib/collection/maps.dart */ putIfAbsent(covariant-by-class self::_MyMap&Object&MapMixin::K% key, covariant-by-class () → self::_MyMap&Object&MapMixin::V% ifAbsent) → self::_MyMap&Object&MapMixin::V% {
     if(this.{col::MapBase::containsKey}(key){(core::Object?) → core::bool}) {
-      return let self::_MyMap&Object&MapMixin::V? #t2 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t2 == null ?{self::_MyMap&Object&MapMixin::V%} #t2 as{Unchecked} self::_MyMap&Object&MapMixin::V% : #t2{self::_MyMap&Object&MapMixin::V%};
+      return let self::_MyMap&Object&MapMixin::V? #t3 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t3 == null ?{self::_MyMap&Object&MapMixin::V%} let self::_MyMap&Object&MapMixin::V? #t4 = #t3 in #t4 == null ?{self::_MyMap&Object&MapMixin::V%} #t4 as self::_MyMap&Object&MapMixin::V% : #t4{self::_MyMap&Object&MapMixin::V%} : #t3{self::_MyMap&Object&MapMixin::V%};
     }
-    return let final self::_MyMap&Object&MapMixin::K% #t3 = key in let final self::_MyMap&Object&MapMixin::V% #t4 = ifAbsent(){() → self::_MyMap&Object&MapMixin::V%} in let final void #t5 = this.{col::MapBase::[]=}(#t3, #t4){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → void} in #t4;
+    return let final self::_MyMap&Object&MapMixin::K% #t5 = key in let final self::_MyMap&Object&MapMixin::V% #t6 = ifAbsent(){() → self::_MyMap&Object&MapMixin::V%} in let final void #t7 = this.{col::MapBase::[]=}(#t5, #t6){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → void} in #t6;
   }
   method /* from org-dartlang-sdk:///sdk/lib/collection/maps.dart */ update(covariant-by-class self::_MyMap&Object&MapMixin::K% key, covariant-by-class (self::_MyMap&Object&MapMixin::V%) → self::_MyMap&Object&MapMixin::V% update, {covariant-by-class () →? self::_MyMap&Object&MapMixin::V% ifAbsent = #C1}) → self::_MyMap&Object&MapMixin::V% {
     if(this.{col::MapBase::containsKey}(key){(core::Object?) → core::bool}) {
-      return let final self::_MyMap&Object&MapMixin::K% #t6 = key in let final self::_MyMap&Object&MapMixin::V% #t7 = update(let self::_MyMap&Object&MapMixin::V? #t8 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t8 == null ?{self::_MyMap&Object&MapMixin::V%} #t8 as{Unchecked} self::_MyMap&Object&MapMixin::V% : #t8{self::_MyMap&Object&MapMixin::V%}){(self::_MyMap&Object&MapMixin::V%) → self::_MyMap&Object&MapMixin::V%} in let final void #t9 = this.{col::MapBase::[]=}(#t6, #t7){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → void} in #t7;
+      return let final self::_MyMap&Object&MapMixin::K% #t8 = key in let final self::_MyMap&Object&MapMixin::V% #t9 = update(let self::_MyMap&Object&MapMixin::V? #t10 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t10 == null ?{self::_MyMap&Object&MapMixin::V%} let self::_MyMap&Object&MapMixin::V? #t11 = #t10 in #t11 == null ?{self::_MyMap&Object&MapMixin::V%} #t11 as self::_MyMap&Object&MapMixin::V% : #t11{self::_MyMap&Object&MapMixin::V%} : #t10{self::_MyMap&Object&MapMixin::V%}){(self::_MyMap&Object&MapMixin::V%) → self::_MyMap&Object&MapMixin::V%} in let final void #t12 = this.{col::MapBase::[]=}(#t8, #t9){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → void} in #t9;
     }
     if(!(ifAbsent == null)) {
-      return let final self::_MyMap&Object&MapMixin::K% #t10 = key in let final self::_MyMap&Object&MapMixin::V% #t11 = ifAbsent{() → self::_MyMap&Object&MapMixin::V%}(){() → self::_MyMap&Object&MapMixin::V%} in let final void #t12 = this.{col::MapBase::[]=}(#t10, #t11){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → void} in #t11;
+      return let final self::_MyMap&Object&MapMixin::K% #t13 = key in let final self::_MyMap&Object&MapMixin::V% #t14 = ifAbsent{() → self::_MyMap&Object&MapMixin::V%}(){() → self::_MyMap&Object&MapMixin::V%} in let final void #t15 = this.{col::MapBase::[]=}(#t13, #t14){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → void} in #t14;
     }
     throw new core::ArgumentError::value(key, "key", "Key not in map.");
   }
@@ -69,13 +69,13 @@ abstract class _MyMap&Object&MapMixin<K extends core::Object? = dynamic, V exten
       for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
         self::_MyMap&Object&MapMixin::K% key = :sync-for-iterator.{core::Iterator::current}{self::_MyMap&Object&MapMixin::K%};
         {
-          this.{col::MapBase::[]=}(key, update(key, let self::_MyMap&Object&MapMixin::V? #t13 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t13 == null ?{self::_MyMap&Object&MapMixin::V%} #t13 as{Unchecked} self::_MyMap&Object&MapMixin::V% : #t13{self::_MyMap&Object&MapMixin::V%}){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → self::_MyMap&Object&MapMixin::V%}){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → void};
+          this.{col::MapBase::[]=}(key, update(key, let self::_MyMap&Object&MapMixin::V? #t16 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t16 == null ?{self::_MyMap&Object&MapMixin::V%} let self::_MyMap&Object&MapMixin::V? #t17 = #t16 in #t17 == null ?{self::_MyMap&Object&MapMixin::V%} #t17 as self::_MyMap&Object&MapMixin::V% : #t17{self::_MyMap&Object&MapMixin::V%} : #t16{self::_MyMap&Object&MapMixin::V%}){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → self::_MyMap&Object&MapMixin::V%}){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → void};
         }
       }
     }
   }
   get /* from org-dartlang-sdk:///sdk/lib/collection/maps.dart */ entries() → core::Iterable<core::MapEntry<self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%>> {
-    return this.{col::MapBase::keys}{core::Iterable<self::_MyMap&Object&MapMixin::K%>}.{core::Iterable::map}<core::MapEntry<self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%>>((self::_MyMap&Object&MapMixin::K% key) → core::MapEntry<self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%> => new core::MapEntry::_<self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%>(key, let self::_MyMap&Object&MapMixin::V? #t14 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t14 == null ?{self::_MyMap&Object&MapMixin::V%} #t14 as{Unchecked} self::_MyMap&Object&MapMixin::V% : #t14{self::_MyMap&Object&MapMixin::V%})){((self::_MyMap&Object&MapMixin::K%) → core::MapEntry<self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%>) → core::Iterable<core::MapEntry<self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%>>};
+    return this.{col::MapBase::keys}{core::Iterable<self::_MyMap&Object&MapMixin::K%>}.{core::Iterable::map}<core::MapEntry<self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%>>((self::_MyMap&Object&MapMixin::K% key) → core::MapEntry<self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%> => new core::MapEntry::_<self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%>(key, let self::_MyMap&Object&MapMixin::V? #t18 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t18 == null ?{self::_MyMap&Object&MapMixin::V%} let self::_MyMap&Object&MapMixin::V? #t19 = #t18 in #t19 == null ?{self::_MyMap&Object&MapMixin::V%} #t19 as self::_MyMap&Object&MapMixin::V% : #t19{self::_MyMap&Object&MapMixin::V%} : #t18{self::_MyMap&Object&MapMixin::V%})){((self::_MyMap&Object&MapMixin::K%) → core::MapEntry<self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%>) → core::Iterable<core::MapEntry<self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%>>};
   }
   method /* from org-dartlang-sdk:///sdk/lib/collection/maps.dart */ map<K2 extends core::Object? = dynamic, V2 extends core::Object? = dynamic>((self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → core::MapEntry<self::_MyMap&Object&MapMixin::map::K2%, self::_MyMap&Object&MapMixin::map::V2%> transform) → core::Map<self::_MyMap&Object&MapMixin::map::K2%, self::_MyMap&Object&MapMixin::map::V2%> {
     core::Map<self::_MyMap&Object&MapMixin::map::K2%, self::_MyMap&Object&MapMixin::map::V2%> result = <self::_MyMap&Object&MapMixin::map::K2%, self::_MyMap&Object&MapMixin::map::V2%>{};
@@ -84,7 +84,7 @@ abstract class _MyMap&Object&MapMixin<K extends core::Object? = dynamic, V exten
       for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
         self::_MyMap&Object&MapMixin::K% key = :sync-for-iterator.{core::Iterator::current}{self::_MyMap&Object&MapMixin::K%};
         {
-          core::MapEntry<self::_MyMap&Object&MapMixin::map::K2%, self::_MyMap&Object&MapMixin::map::V2%> entry = transform(key, let self::_MyMap&Object&MapMixin::V? #t15 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t15 == null ?{self::_MyMap&Object&MapMixin::V%} #t15 as{Unchecked} self::_MyMap&Object&MapMixin::V% : #t15{self::_MyMap&Object&MapMixin::V%}){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → core::MapEntry<self::_MyMap&Object&MapMixin::map::K2%, self::_MyMap&Object&MapMixin::map::V2%>};
+          core::MapEntry<self::_MyMap&Object&MapMixin::map::K2%, self::_MyMap&Object&MapMixin::map::V2%> entry = transform(key, let self::_MyMap&Object&MapMixin::V? #t20 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t20 == null ?{self::_MyMap&Object&MapMixin::V%} let self::_MyMap&Object&MapMixin::V? #t21 = #t20 in #t21 == null ?{self::_MyMap&Object&MapMixin::V%} #t21 as self::_MyMap&Object&MapMixin::V% : #t21{self::_MyMap&Object&MapMixin::V%} : #t20{self::_MyMap&Object&MapMixin::V%}){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → core::MapEntry<self::_MyMap&Object&MapMixin::map::K2%, self::_MyMap&Object&MapMixin::map::V2%>};
           result.{core::Map::[]=}(entry.{core::MapEntry::key}{self::_MyMap&Object&MapMixin::map::K2%}, entry.{core::MapEntry::value}{self::_MyMap&Object&MapMixin::map::V2%}){(self::_MyMap&Object&MapMixin::map::K2%, self::_MyMap&Object&MapMixin::map::V2%) → void};
         }
       }
@@ -109,7 +109,7 @@ abstract class _MyMap&Object&MapMixin<K extends core::Object? = dynamic, V exten
       for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
         self::_MyMap&Object&MapMixin::K% key = :sync-for-iterator.{core::Iterator::current}{self::_MyMap&Object&MapMixin::K%};
         {
-          if(test(key, let self::_MyMap&Object&MapMixin::V? #t16 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t16 == null ?{self::_MyMap&Object&MapMixin::V%} #t16 as{Unchecked} self::_MyMap&Object&MapMixin::V% : #t16{self::_MyMap&Object&MapMixin::V%}){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → core::bool})
+          if(test(key, let self::_MyMap&Object&MapMixin::V? #t22 = this.{col::MapBase::[]}(key){(core::Object?) → self::_MyMap&Object&MapMixin::V?} in #t22 == null ?{self::_MyMap&Object&MapMixin::V%} let self::_MyMap&Object&MapMixin::V? #t23 = #t22 in #t23 == null ?{self::_MyMap&Object&MapMixin::V%} #t23 as self::_MyMap&Object&MapMixin::V% : #t23{self::_MyMap&Object&MapMixin::V%} : #t22{self::_MyMap&Object&MapMixin::V%}){(self::_MyMap&Object&MapMixin::K%, self::_MyMap&Object&MapMixin::V%) → core::bool})
             keysToRemove.{core::List::add}(key){(self::_MyMap&Object&MapMixin::K%) → void};
         }
       }
@@ -206,7 +206,7 @@ class MyMap<K extends core::Object? = dynamic, V extends core::Object? = dynamic
     return this.{self::MyMap::_map}{core::Map<self::MyMap::K%, self::MyMap::V%>}.{core::Map::[]}(key){(core::Object?) → self::MyMap::V?};
   }
   operator []=(covariant-by-class self::MyMap::K% key, covariant-by-class self::MyMap::V% value) → void
-    return let final core::Map<self::MyMap::K%, self::MyMap::V%> #t17 = this.{self::MyMap::_map}{core::Map<self::MyMap::K%, self::MyMap::V%>} in let final self::MyMap::K% #t18 = key in let final self::MyMap::V% #t19 = value in let final void #t20 = #t17.{core::Map::[]=}(#t18, #t19){(self::MyMap::K%, self::MyMap::V%) → void} in #t19;
+    return let final core::Map<self::MyMap::K%, self::MyMap::V%> #t24 = this.{self::MyMap::_map}{core::Map<self::MyMap::K%, self::MyMap::V%>} in let final self::MyMap::K% #t25 = key in let final self::MyMap::V% #t26 = value in let final void #t27 = #t24.{core::Map::[]=}(#t25, #t26){(self::MyMap::K%, self::MyMap::V%) → void} in #t26;
   method clear() → void
     return this.{self::MyMap::_map}{core::Map<self::MyMap::K%, self::MyMap::V%>}.{core::Map::clear}(){() → void};
   get keys() → core::Iterable<self::MyMap::K%>
@@ -225,14 +225,14 @@ static method method(core::Map<core::int, core::String?> m) → core::int {
     synthesized core::String? #0#3;
     synthesized core::bool #0#3#isSet = false;
     {
-      if((#0#2#isSet ?{core::bool} #0#2{core::bool} : let final core::bool #t21 = #0#2#isSet = true in #0#2 = #0#0.{core::Map::containsKey}(#C4){(core::Object?) → core::bool}) && #C5 =={core::String::==}{(core::Object) → core::bool} (#0#3#isSet ?{core::String?} #0#3{core::String?} : let final core::bool #t22 = #0#3#isSet = true in #0#3 = #0#0.{core::Map::[]}(#C4){(core::Object?) → core::String?})) {
+      if((#0#2#isSet ?{core::bool} #0#2{core::bool} : let final core::bool #t28 = #0#2#isSet = true in #0#2 = #0#0.{core::Map::containsKey}(#C4){(core::Object?) → core::bool}) && #C5 =={core::String::==}{(core::Object) → core::bool} (#0#3#isSet ?{core::String?} #0#3{core::String?} : let final core::bool #t29 = #0#3#isSet = true in #0#3 = #0#0.{core::Map::[]}(#C4){(core::Object?) → core::String?})) {
         {
           return 0;
         }
       }
     }
     {
-      if((#0#2#isSet ?{core::bool} #0#2{core::bool} : let final core::bool #t23 = #0#2#isSet = true in #0#2 = #0#0.{core::Map::containsKey}(#C4){(core::Object?) → core::bool}) && #C6 =={core::String::==}{(core::Object) → core::bool} (#0#3#isSet ?{core::String?} #0#3{core::String?} : let final core::bool #t24 = #0#3#isSet = true in #0#3 = #0#0.{core::Map::[]}(#C4){(core::Object?) → core::String?})) {
+      if((#0#2#isSet ?{core::bool} #0#2{core::bool} : let final core::bool #t30 = #0#2#isSet = true in #0#2 = #0#0.{core::Map::containsKey}(#C4){(core::Object?) → core::bool}) && #C6 =={core::String::==}{(core::Object) → core::bool} (#0#3#isSet ?{core::String?} #0#3{core::String?} : let final core::bool #t31 = #0#3#isSet = true in #0#3 = #0#0.{core::Map::[]}(#C4){(core::Object?) → core::String?})) {
         {
           return 1;
         }
@@ -269,4 +269,4 @@ constants  {
 
 Extra constant evaluation status:
 Evaluated: IsExpression @ org-dartlang-testcase:///caching_constants.dart:7:49 -> BoolConstant(true)
-Extra constant evaluation: evaluated: 445, effectively constant: 1
+Extra constant evaluation: evaluated: 487, effectively constant: 1
diff --git a/pkg/front_end/testcases/patterns/cast_inside_extractor_pattern.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/cast_inside_extractor_pattern.dart.weak.transformed.expect
index e33f622ac7f..54fc1be3700 100644
--- a/pkg/front_end/testcases/patterns/cast_inside_extractor_pattern.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/cast_inside_extractor_pattern.dart.weak.transformed.expect
@@ -15,7 +15,7 @@ static method test(dynamic x) → dynamic {
     synthesized core::int? #0#2;
     synthesized core::bool #0#2#isSet = false;
     {
-      if(#0#0 is self::C && (let final core::int #t1 = (#0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t2 = #0#2#isSet = true in #0#2 = #0#0{self::C}.{self::C::f}{core::int?}) as{Unchecked} core::int in #C1 =={core::num::==}{(core::Object) → core::bool} (#0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t3 = #0#2#isSet = true in #0#2 = #0#0{self::C}.{self::C::f}{core::int?}) as{Unchecked} core::int)) {
+      if(#0#0 is self::C && (let final core::int #t1 = let core::int? #t2 = #0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t3 = #0#2#isSet = true in #0#2 = #0#0{self::C}.{self::C::f}{core::int?} in #t2 == null ?{core::int} #t2 as core::int : #t2{core::int} in #C1 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t4 = #0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t5 = #0#2#isSet = true in #0#2 = #0#0{self::C}.{self::C::f}{core::int?} in #t4 == null ?{core::int} #t4 as core::int : #t4{core::int}))) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/cast_inside_extractor_pattern_implicitly_named.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/cast_inside_extractor_pattern_implicitly_named.dart.weak.transformed.expect
index aced95f5706..fc50a3d4b0e 100644
--- a/pkg/front_end/testcases/patterns/cast_inside_extractor_pattern_implicitly_named.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/cast_inside_extractor_pattern_implicitly_named.dart.weak.transformed.expect
@@ -16,7 +16,7 @@ static method test(dynamic x) → dynamic {
     synthesized core::bool #0#2#isSet = false;
     {
       hoisted core::int f;
-      if(#0#0 is self::C && (let final core::int #t1 = (#0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t2 = #0#2#isSet = true in #0#2 = #0#0{self::C}.{self::C::f}{core::int?}) as{Unchecked} core::int in let final core::int #t3 = f = (#0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t4 = #0#2#isSet = true in #0#2 = #0#0{self::C}.{self::C::f}{core::int?}) as{Unchecked} core::int in true)) {
+      if(#0#0 is self::C && (let final core::int #t1 = let core::int? #t2 = #0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t3 = #0#2#isSet = true in #0#2 = #0#0{self::C}.{self::C::f}{core::int?} in #t2 == null ?{core::int} #t2 as core::int : #t2{core::int} in let final core::int #t4 = f = let core::int? #t5 = #0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t6 = #0#2#isSet = true in #0#2 = #0#0{self::C}.{self::C::f}{core::int?} in #t5 == null ?{core::int} #t5 as core::int : #t5{core::int} in true)) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/constant_identifier_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/constant_identifier_inside_cast.dart.weak.transformed.expect
index 2bc5772600b..e18431c736b 100644
--- a/pkg/front_end/testcases/patterns/constant_identifier_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/constant_identifier_inside_cast.dart.weak.transformed.expect
@@ -7,7 +7,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in #C1 =={core::num::==}{(core::Object) → core::bool} #0#0 as{Unchecked} core::Object) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in #C1 =={core::num::==}{(core::Object) → core::bool} (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object})) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/double_literal_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/double_literal_inside_cast.dart.weak.transformed.expect
index bdb4ea685f5..21f05a673fc 100644
--- a/pkg/front_end/testcases/patterns/double_literal_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/double_literal_inside_cast.dart.weak.transformed.expect
@@ -7,7 +7,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in #C1 =={core::num::==}{(core::Object) → core::bool} #0#0 as{Unchecked} core::Object) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in #C1 =={core::num::==}{(core::Object) → core::bool} (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object})) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/exhaustiveness/nullable_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/exhaustiveness/nullable_cast.dart.weak.transformed.expect
index 1ed3a7b301d..160a974673b 100644
--- a/pkg/front_end/testcases/patterns/exhaustiveness/nullable_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/exhaustiveness/nullable_cast.dart.weak.transformed.expect
@@ -29,7 +29,7 @@ static method exhaustiveNonNullableType(core::int? o) → dynamic
     #L2:
     {
       {
-        if(let final core::int #t4 = #0#0 as{Unchecked} core::int in true) {
+        if(let final core::int #t4 = let core::int? #t5 = #0#0 in #t5 == null ?{core::int} #t5 as core::int : #t5{core::int} in true) {
           #t3 = 0;
           break #L2;
         }
@@ -39,79 +39,79 @@ static method exhaustiveNonNullableType(core::int? o) → dynamic
   } =>#t3;
 static method exhaustiveNonNullableSuperType(core::int? o) → dynamic
   return block {
-    core::int #t5;
+    core::int #t6;
     final synthesized core::int? #0#0 = o;
     #L3:
     {
       {
-        if(let final core::num #t6 = #0#0 as{Unchecked} core::num in (#0#0 as{Unchecked} core::num) is core::int) {
-          #t5 = 0;
+        if(let final core::num #t7 = let core::int? #t8 = #0#0 in #t8 == null ?{core::num} #t8 as core::num : #t8{core::num} in (let core::int? #t9 = #0#0 in #t9 == null ?{core::num} #t9 as core::num : #t9{core::num}) is core::int) {
+          #t6 = 0;
           break #L3;
         }
       }
       throw{for-error-handling} new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable type.");
     }
-  } =>#t5;
+  } =>#t6;
 static method exhaustiveNonNullableFutureOr1(FutureOr<core::int>? o) → dynamic
   return block {
-    core::int #t7;
+    core::int #t10;
     final synthesized FutureOr<core::int>? #0#0 = o;
     #L4:
     {
       {
-        if(let final FutureOr<core::int>#t8 = #0#0 as{Unchecked} FutureOr<core::int> in true) {
-          #t7 = 0;
+        if(let final FutureOr<core::int>#t11 = let FutureOr<core::int>? #t12 = #0#0 in #t12 == null ?{FutureOr<core::int>} #t12 as FutureOr<core::int> : #t12{FutureOr<core::int>} in true) {
+          #t10 = 0;
           break #L4;
         }
       }
       throw{for-error-handling} new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable type.");
     }
-  } =>#t7;
+  } =>#t10;
 static method exhaustiveNonNullableFutureOr2(FutureOr<core::int?>o) → dynamic
   return block {
-    core::int #t9;
+    core::int #t13;
     final synthesized FutureOr<core::int?>#0#0 = o;
     #L5:
     {
       {
-        if(let final FutureOr<core::int>#t10 = #0#0 as{Unchecked} FutureOr<core::int> in true) {
-          #t9 = 0;
+        if(let final FutureOr<core::int>#t14 = #0#0 as FutureOr<core::int> in true) {
+          #t13 = 0;
           break #L5;
         }
       }
       throw{for-error-handling} new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable type.");
     }
-  } =>#t9;
+  } =>#t13;
 static method exhaustiveNonNullableFutureOrTypeVariable1<T extends core::Object>(FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable1::T>? o) → dynamic
   return block {
-    core::int #t11;
+    core::int #t15;
     final synthesized FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable1::T>? #0#0 = o;
     #L6:
     {
       {
-        if(let final FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable1::T>#t12 = #0#0 as{Unchecked} FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable1::T> in true) {
-          #t11 = 0;
+        if(let final FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable1::T>#t16 = let FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable1::T>? #t17 = #0#0 in #t17 == null ?{FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable1::T>} #t17 as FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable1::T> : #t17{FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable1::T>} in true) {
+          #t15 = 0;
           break #L6;
         }
       }
       throw{for-error-handling} new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable type.");
     }
-  } =>#t11;
+  } =>#t15;
 static method exhaustiveNonNullableFutureOrTypeVariable2<T extends core::Object>(FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable2::T?>o) → dynamic
   return block {
-    core::int #t13;
+    core::int #t18;
     final synthesized FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable2::T?>#0#0 = o;
     #L7:
     {
       {
-        if(let final FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable2::T>#t14 = #0#0 as{Unchecked} FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable2::T> in true) {
-          #t13 = 0;
+        if(let final FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable2::T>#t19 = #0#0 as FutureOr<self::exhaustiveNonNullableFutureOrTypeVariable2::T> in true) {
+          #t18 = 0;
           break #L7;
         }
       }
       throw{for-error-handling} new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable type.");
     }
-  } =>#t13;
+  } =>#t18;
 static method main() → dynamic {
   self::expect(0, self::exhaustiveNonNullableTypeVariable<core::Object>(42));
   self::expect(0, self::exhaustiveNonNullableTypeVariable<core::int>(42));
@@ -165,4 +165,4 @@ constants  {
 
 Extra constant evaluation status:
 Evaluated: IsExpression @ org-dartlang-testcase:///nullable_cast.dart:78:40 -> BoolConstant(true)
-Extra constant evaluation: evaluated: 147, effectively constant: 1
+Extra constant evaluation: evaluated: 177, effectively constant: 1
diff --git a/pkg/front_end/testcases/patterns/extractor_pattern_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/extractor_pattern_inside_cast.dart.weak.transformed.expect
index edda7195f91..77033f98e91 100644
--- a/pkg/front_end/testcases/patterns/extractor_pattern_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/extractor_pattern_inside_cast.dart.weak.transformed.expect
@@ -13,7 +13,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in (#0#0 as{Unchecked} core::Object) is self::C && #C1 =={core::num::==}{(core::Object) → core::bool} ((#0#0 as{Unchecked} core::Object) as{Unchecked} self::C).{self::C::f}{core::int?}) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object}) is self::C && #C1 =={core::num::==}{(core::Object) → core::bool} ((let dynamic #t4 = #0#0 in #t4 == null ?{core::Object} #t4 as core::Object : #t4{core::Object}) as{Unchecked} self::C).{self::C::f}{core::int?}) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/final_variable_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/final_variable_inside_cast.dart.weak.transformed.expect
index cbc635dee7b..f5ee41a8f02 100644
--- a/pkg/front_end/testcases/patterns/final_variable_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/final_variable_inside_cast.dart.weak.transformed.expect
@@ -8,7 +8,7 @@ static method test(dynamic x) → dynamic {
     final synthesized dynamic #0#0 = x;
     {
       final hoisted core::Object y;
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in let final core::Object #t2 = y = #0#0 as{Unchecked} core::Object in true) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in let final core::Object #t3 = y = let dynamic #t4 = #0#0 in #t4 == null ?{core::Object} #t4 as core::Object : #t4{core::Object} in true) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/identical_map_keys.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/identical_map_keys.dart.weak.transformed.expect
index 081c71eaa1a..222644199c2 100644
--- a/pkg/front_end/testcases/patterns/identical_map_keys.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/identical_map_keys.dart.weak.transformed.expect
@@ -404,7 +404,7 @@ static method test() → dynamic {
     synthesized core::bool #0#2#isSet = false;
     synthesized core::int? #0#3;
     synthesized core::bool #0#3#isSet = false;
-    if(!((#0#2#isSet ?{core::bool} #0#2{core::bool} : let final core::bool #t74 = #0#2#isSet = true in #0#2 = #0#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool}) && (let final core::int #t75 = a = (#0#3#isSet ?{core::int?} #0#3{core::int?} : let final core::bool #t76 = #0#3#isSet = true in #0#3 = #0#0.{core::Map::[]}(#C1){(core::Object?) → core::int?}) as{Unchecked} core::int in true) && (#0#2#isSet ?{core::bool} #0#2{core::bool} : let final core::bool #t77 = #0#2#isSet = true in #0#2 = #0#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool}) && (let final core::int #t78 = b = (#0#3#isSet ?{core::int?} #0#3{core::int?} : let final core::bool #t79 = #0#3#isSet = true in #0#3 = #0#0.{core::Map::[]}(#C1){(core::Object?) → core::int?}) as{Unchecked} core::int in true)))
+    if(!((#0#2#isSet ?{core::bool} #0#2{core::bool} : let final core::bool #t74 = #0#2#isSet = true in #0#2 = #0#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool}) && (let final core::int #t75 = a = let core::int? #t76 = #0#3#isSet ?{core::int?} #0#3{core::int?} : let final core::bool #t77 = #0#3#isSet = true in #0#3 = #0#0.{core::Map::[]}(#C1){(core::Object?) → core::int?} in #t76 == null ?{core::int} #t76 as{Unchecked} core::int : #t76{core::int} in true) && (#0#2#isSet ?{core::bool} #0#2{core::bool} : let final core::bool #t78 = #0#2#isSet = true in #0#2 = #0#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool}) && (let final core::int #t79 = b = let core::int? #t80 = #0#3#isSet ?{core::int?} #0#3{core::int?} : let final core::bool #t81 = #0#3#isSet = true in #0#3 = #0#0.{core::Map::[]}(#C1){(core::Object?) → core::int?} in #t80 == null ?{core::int} #t80 as{Unchecked} core::int : #t80{core::int} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
   hoisted has-declared-initializer core::int c;
@@ -415,7 +415,7 @@ static method test() → dynamic {
     synthesized core::bool #1#2#isSet = false;
     synthesized core::int? #1#3;
     synthesized core::bool #1#3#isSet = false;
-    if(!((#1#2#isSet ?{core::bool} #1#2{core::bool} : let final core::bool #t80 = #1#2#isSet = true in #1#2 = #1#0.{core::Map::containsKey}(#C2){(core::Object?) → core::bool}) && (let final core::int #t81 = c = (#1#3#isSet ?{core::int?} #1#3{core::int?} : let final core::bool #t82 = #1#3#isSet = true in #1#3 = #1#0.{core::Map::[]}(#C2){(core::Object?) → core::int?}) as{Unchecked} core::int in true) && (#1#2#isSet ?{core::bool} #1#2{core::bool} : let final core::bool #t83 = #1#2#isSet = true in #1#2 = #1#0.{core::Map::containsKey}(#C2){(core::Object?) → core::bool}) && (let final core::int #t84 = d = (#1#3#isSet ?{core::int?} #1#3{core::int?} : let final core::bool #t85 = #1#3#isSet = true in #1#3 = #1#0.{core::Map::[]}(#C2){(core::Object?) → core::int?}) as{Unchecked} core::int in true)))
+    if(!((#1#2#isSet ?{core::bool} #1#2{core::bool} : let final core::bool #t82 = #1#2#isSet = true in #1#2 = #1#0.{core::Map::containsKey}(#C2){(core::Object?) → core::bool}) && (let final core::int #t83 = c = let core::int? #t84 = #1#3#isSet ?{core::int?} #1#3{core::int?} : let final core::bool #t85 = #1#3#isSet = true in #1#3 = #1#0.{core::Map::[]}(#C2){(core::Object?) → core::int?} in #t84 == null ?{core::int} #t84 as{Unchecked} core::int : #t84{core::int} in true) && (#1#2#isSet ?{core::bool} #1#2{core::bool} : let final core::bool #t86 = #1#2#isSet = true in #1#2 = #1#0.{core::Map::containsKey}(#C2){(core::Object?) → core::bool}) && (let final core::int #t87 = d = let core::int? #t88 = #1#3#isSet ?{core::int?} #1#3{core::int?} : let final core::bool #t89 = #1#3#isSet = true in #1#3 = #1#0.{core::Map::[]}(#C2){(core::Object?) → core::int?} in #t88 == null ?{core::int} #t88 as{Unchecked} core::int : #t88{core::int} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
   final hoisted has-declared-initializer core::int a1;
@@ -426,7 +426,7 @@ static method test() → dynamic {
     synthesized core::bool #2#2#isSet = false;
     synthesized core::int? #2#3;
     synthesized core::bool #2#3#isSet = false;
-    if(!((#2#2#isSet ?{core::bool} #2#2{core::bool} : let final core::bool #t86 = #2#2#isSet = true in #2#2 = #2#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool}) && (let final core::int #t87 = a1 = (#2#3#isSet ?{core::int?} #2#3{core::int?} : let final core::bool #t88 = #2#3#isSet = true in #2#3 = #2#0.{core::Map::[]}(#C1){(core::Object?) → core::int?}) as{Unchecked} core::int in true) && (#2#2#isSet ?{core::bool} #2#2{core::bool} : let final core::bool #t89 = #2#2#isSet = true in #2#2 = #2#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool}) && (let final core::int #t90 = b1 = (#2#3#isSet ?{core::int?} #2#3{core::int?} : let final core::bool #t91 = #2#3#isSet = true in #2#3 = #2#0.{core::Map::[]}(#C1){(core::Object?) → core::int?}) as{Unchecked} core::int in true)))
+    if(!((#2#2#isSet ?{core::bool} #2#2{core::bool} : let final core::bool #t90 = #2#2#isSet = true in #2#2 = #2#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool}) && (let final core::int #t91 = a1 = let core::int? #t92 = #2#3#isSet ?{core::int?} #2#3{core::int?} : let final core::bool #t93 = #2#3#isSet = true in #2#3 = #2#0.{core::Map::[]}(#C1){(core::Object?) → core::int?} in #t92 == null ?{core::int} #t92 as{Unchecked} core::int : #t92{core::int} in true) && (#2#2#isSet ?{core::bool} #2#2{core::bool} : let final core::bool #t94 = #2#2#isSet = true in #2#2 = #2#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool}) && (let final core::int #t95 = b1 = let core::int? #t96 = #2#3#isSet ?{core::int?} #2#3{core::int?} : let final core::bool #t97 = #2#3#isSet = true in #2#3 = #2#0.{core::Map::[]}(#C1){(core::Object?) → core::int?} in #t96 == null ?{core::int} #t96 as{Unchecked} core::int : #t96{core::int} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
   final hoisted has-declared-initializer core::int a2;
@@ -437,7 +437,7 @@ static method test() → dynamic {
     synthesized core::bool #3#2#isSet = false;
     synthesized core::int? #3#3;
     synthesized core::bool #3#3#isSet = false;
-    if(!((#3#2#isSet ?{core::bool} #3#2{core::bool} : let final core::bool #t92 = #3#2#isSet = true in #3#2 = #3#0.{core::Map::containsKey}(#C4){(core::Object?) → core::bool}) && (let final core::int #t93 = a2 = (#3#3#isSet ?{core::int?} #3#3{core::int?} : let final core::bool #t94 = #3#3#isSet = true in #3#3 = #3#0.{core::Map::[]}(#C4){(core::Object?) → core::int?}) as{Unchecked} core::int in true) && (#3#2#isSet ?{core::bool} #3#2{core::bool} : let final core::bool #t95 = #3#2#isSet = true in #3#2 = #3#0.{core::Map::containsKey}(#C4){(core::Object?) → core::bool}) && (let final core::int #t96 = b2 = (#3#3#isSet ?{core::int?} #3#3{core::int?} : let final core::bool #t97 = #3#3#isSet = true in #3#3 = #3#0.{core::Map::[]}(#C4){(core::Object?) → core::int?}) as{Unchecked} core::int in true)))
+    if(!((#3#2#isSet ?{core::bool} #3#2{core::bool} : let final core::bool #t98 = #3#2#isSet = true in #3#2 = #3#0.{core::Map::containsKey}(#C4){(core::Object?) → core::bool}) && (let final core::int #t99 = a2 = let core::int? #t100 = #3#3#isSet ?{core::int?} #3#3{core::int?} : let final core::bool #t101 = #3#3#isSet = true in #3#3 = #3#0.{core::Map::[]}(#C4){(core::Object?) → core::int?} in #t100 == null ?{core::int} #t100 as{Unchecked} core::int : #t100{core::int} in true) && (#3#2#isSet ?{core::bool} #3#2{core::bool} : let final core::bool #t102 = #3#2#isSet = true in #3#2 = #3#0.{core::Map::containsKey}(#C4){(core::Object?) → core::bool}) && (let final core::int #t103 = b2 = let core::int? #t104 = #3#3#isSet ?{core::int?} #3#3{core::int?} : let final core::bool #t105 = #3#3#isSet = true in #3#3 = #3#0.{core::Map::[]}(#C4){(core::Object?) → core::int?} in #t104 == null ?{core::int} #t104 as{Unchecked} core::int : #t104{core::int} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
   final hoisted has-declared-initializer core::int a3;
@@ -448,7 +448,7 @@ static method test() → dynamic {
     synthesized core::bool #4#2#isSet = false;
     synthesized core::int? #4#3;
     synthesized core::bool #4#3#isSet = false;
-    if(!((#4#2#isSet ?{core::bool} #4#2{core::bool} : let final core::bool #t98 = #4#2#isSet = true in #4#2 = #4#0.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && (let final core::int #t99 = a3 = (#4#3#isSet ?{core::int?} #4#3{core::int?} : let final core::bool #t100 = #4#3#isSet = true in #4#3 = #4#0.{core::Map::[]}(#C5){(core::Object?) → core::int?}) as{Unchecked} core::int in true) && (#4#2#isSet ?{core::bool} #4#2{core::bool} : let final core::bool #t101 = #4#2#isSet = true in #4#2 = #4#0.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && (let final core::int #t102 = b3 = (#4#3#isSet ?{core::int?} #4#3{core::int?} : let final core::bool #t103 = #4#3#isSet = true in #4#3 = #4#0.{core::Map::[]}(#C5){(core::Object?) → core::int?}) as{Unchecked} core::int in true)))
+    if(!((#4#2#isSet ?{core::bool} #4#2{core::bool} : let final core::bool #t106 = #4#2#isSet = true in #4#2 = #4#0.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && (let final core::int #t107 = a3 = let core::int? #t108 = #4#3#isSet ?{core::int?} #4#3{core::int?} : let final core::bool #t109 = #4#3#isSet = true in #4#3 = #4#0.{core::Map::[]}(#C5){(core::Object?) → core::int?} in #t108 == null ?{core::int} #t108 as{Unchecked} core::int : #t108{core::int} in true) && (#4#2#isSet ?{core::bool} #4#2{core::bool} : let final core::bool #t110 = #4#2#isSet = true in #4#2 = #4#0.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && (let final core::int #t111 = b3 = let core::int? #t112 = #4#3#isSet ?{core::int?} #4#3{core::int?} : let final core::bool #t113 = #4#3#isSet = true in #4#3 = #4#0.{core::Map::[]}(#C5){(core::Object?) → core::int?} in #t112 == null ?{core::int} #t112 as{Unchecked} core::int : #t112{core::int} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
 }
diff --git a/pkg/front_end/testcases/patterns/integer_literal_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/integer_literal_inside_cast.dart.weak.transformed.expect
index 2bc5772600b..e18431c736b 100644
--- a/pkg/front_end/testcases/patterns/integer_literal_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/integer_literal_inside_cast.dart.weak.transformed.expect
@@ -7,7 +7,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in #C1 =={core::num::==}{(core::Object) → core::bool} #0#0 as{Unchecked} core::Object) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in #C1 =={core::num::==}{(core::Object) → core::bool} (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object})) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/issue50886.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/issue50886.dart.weak.transformed.expect
index ddc26f7047b..aaa702d1ea6 100644
--- a/pkg/front_end/testcases/patterns/issue50886.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/issue50886.dart.weak.transformed.expect
@@ -6,7 +6,7 @@ static method test1() → dynamic {
   core::Map<dynamic, dynamic> x = <dynamic, dynamic>{1: 1};
   {
     final synthesized core::Map<dynamic, dynamic> #0#0 = x;
-    if(#0#0 is core::Map<core::int, core::int> && #0#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && #C1 =={core::num::==}{(core::Object) → core::bool} #0#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C1){(core::Object?) → core::int?} as{Unchecked} core::int) {
+    if(#0#0 is core::Map<core::int, core::int> && #0#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && #C1 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t1 = #0#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C1){(core::Object?) → core::int?} in #t1 == null ?{core::int} #t1 as{Unchecked} core::int : #t1{core::int})) {
       return 1;
     }
     else {
@@ -18,7 +18,7 @@ static method test2() → dynamic {
   core::Map<dynamic, dynamic> x = <core::int, core::int>{1: 1, 2: 2};
   {
     final synthesized core::Map<dynamic, dynamic> #0#0 = x;
-    if(#0#0 is core::Map<core::int, core::int> && #0#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && #C1 =={core::num::==}{(core::Object) → core::bool} #0#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C1){(core::Object?) → core::int?} as{Unchecked} core::int) {
+    if(#0#0 is core::Map<core::int, core::int> && #0#0{core::Map<core::int, core::int>}.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && #C1 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t2 = #0#0{core::Map<core::int, core::int>}.{core::Map::[]}(#C1){(core::Object?) → core::int?} in #t2 == null ?{core::int} #t2 as{Unchecked} core::int : #t2{core::int})) {
       return 0;
     }
     else {
diff --git a/pkg/front_end/testcases/patterns/issue51480.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/issue51480.dart.weak.transformed.expect
index e89eeecd976..684059bf5df 100644
--- a/pkg/front_end/testcases/patterns/issue51480.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/issue51480.dart.weak.transformed.expect
@@ -8,7 +8,7 @@ static method main() → dynamic {
   hoisted has-declared-initializer core::int v;
   {
     final synthesized core::Map<core::String, core::int> #0#0 = <core::String, core::int>{"key": 42};
-    if(!(#0#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && (let final core::int #t1 = v = #0#0.{core::Map::[]}(#C1){(core::Object?) → core::int?} as{Unchecked} core::int in true)))
+    if(!(#0#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && (let final core::int #t1 = v = let core::int? #t2 = #0#0.{core::Map::[]}(#C1){(core::Object?) → core::int?} in #t2 == null ?{core::int} #t2 as{Unchecked} core::int : #t2{core::int} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
   core::print(self::staticTypeOf<core::int>(v));
diff --git a/pkg/front_end/testcases/patterns/issue51523.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/issue51523.dart.weak.transformed.expect
index 6d4c961a4d7..32a09cab3e0 100644
--- a/pkg/front_end/testcases/patterns/issue51523.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/issue51523.dart.weak.transformed.expect
@@ -11,7 +11,7 @@ static method main() → void {
   hoisted has-declared-initializer core::int a1;
   {
     final synthesized core::Map<self::C<core::String>, core::int> #0#0 = <self::C<core::String>, core::int>{#C1: 1};
-    if(!(#0#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && (let final core::int #t1 = a1 = #0#0.{core::Map::[]}(#C1){(core::Object?) → core::int?} as{Unchecked} core::int in true)))
+    if(!(#0#0.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && (let final core::int #t1 = a1 = let core::int? #t2 = #0#0.{core::Map::[]}(#C1){(core::Object?) → core::int?} in #t2 == null ?{core::int} #t2 as{Unchecked} core::int : #t2{core::int} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
 }
diff --git a/pkg/front_end/testcases/patterns/issue54115.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/issue54115.dart.weak.transformed.expect
index 22774b86318..8bae2707fa4 100644
--- a/pkg/front_end/testcases/patterns/issue54115.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/issue54115.dart.weak.transformed.expect
@@ -33,7 +33,7 @@ class C extends core::Object {
   @#C3
   method promote() → void {
     if(!(this.{self::C::_x}{core::int?} == null))
-      core::print(this.{self::C::_x}{core::int?} as{Unchecked} core::int);
+      core::print(let core::int? #t1 = this.{self::C::_x}{core::int?} in #t1 == null ?{core::int} #t1 as{Unchecked} core::int : #t1{core::int});
     else
       core::print("null");
   }
diff --git a/pkg/front_end/testcases/patterns/issue55310.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/issue55310.dart.weak.transformed.expect
index 9b249ca81f7..1f0c6a877c7 100644
--- a/pkg/front_end/testcases/patterns/issue55310.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/issue55310.dart.weak.transformed.expect
@@ -49,27 +49,27 @@ static method foo(self::Wrapper wrapper) → void {
       {
         final hoisted self::Other other;
         if(#0#0 is self::WrapperA && (#0#3#isSet ?{self::Other?} #0#3{self::Other?} : let final core::bool #t2 = #0#3#isSet = true in #0#3 = #0#0{self::WrapperA}.{self::WrapperA::inner}{self::Inner}.{self::Inner::other}{self::Other?}) is self::Other) {
-          other = (#0#3#isSet ?{self::Other?} #0#3{self::Other?} : let final core::bool #t3 = #0#3#isSet = true in #0#3 = #0#0{self::WrapperA}.{self::WrapperA::inner}{self::Inner}.{self::Inner::other}{self::Other?}) as{Unchecked} self::Other;
+          other = let self::Other? #t3 = #0#3#isSet ?{self::Other?} #0#3{self::Other?} : let final core::bool #t4 = #0#3#isSet = true in #0#3 = #0#0{self::WrapperA}.{self::WrapperA::inner}{self::Inner}.{self::Inner::other}{self::Other?} in #t3 == null ?{self::Other} #t3 as{Unchecked} self::Other : #t3{self::Other};
           #t1 = other.{self::Other::text}{core::String};
           break #L1;
         }
       }
       {
-        if(#0#0 is self::WrapperA && (#0#5#isSet ?{core::bool} #0#5{core::bool} : let final core::bool #t4 = #0#5#isSet = true in #0#5 = (#0#3#isSet ?{self::Other?} #0#3{self::Other?} : let final core::bool #t5 = #0#3#isSet = true in #0#3 = #0#0{self::WrapperA}.{self::WrapperA::inner}{self::Inner}.{self::Inner::other}{self::Other?}) == null)) {
+        if(#0#0 is self::WrapperA && (#0#5#isSet ?{core::bool} #0#5{core::bool} : let final core::bool #t5 = #0#5#isSet = true in #0#5 = (#0#3#isSet ?{self::Other?} #0#3{self::Other?} : let final core::bool #t6 = #0#3#isSet = true in #0#3 = #0#0{self::WrapperA}.{self::WrapperA::inner}{self::Inner}.{self::Inner::other}{self::Other?}) == null)) {
           #t1 = "no other";
           break #L1;
         }
       }
       {
         final hoisted self::Other other;
-        if(#0#0 is self::WrapperB && (#0#3#isSet ?{self::Other?} #0#3{self::Other?} : let final core::bool #t6 = #0#3#isSet = true in #0#3 = #0#0{self::WrapperB}.{self::WrapperB::inner}{self::Inner}.{self::Inner::other}{self::Other?}) is self::Other) {
-          other = (#0#3#isSet ?{self::Other?} #0#3{self::Other?} : let final core::bool #t7 = #0#3#isSet = true in #0#3 = #0#0{self::WrapperB}.{self::WrapperB::inner}{self::Inner}.{self::Inner::other}{self::Other?}) as{Unchecked} self::Other;
+        if(#0#0 is self::WrapperB && (#0#3#isSet ?{self::Other?} #0#3{self::Other?} : let final core::bool #t7 = #0#3#isSet = true in #0#3 = #0#0{self::WrapperB}.{self::WrapperB::inner}{self::Inner}.{self::Inner::other}{self::Other?}) is self::Other) {
+          other = let self::Other? #t8 = #0#3#isSet ?{self::Other?} #0#3{self::Other?} : let final core::bool #t9 = #0#3#isSet = true in #0#3 = #0#0{self::WrapperB}.{self::WrapperB::inner}{self::Inner}.{self::Inner::other}{self::Other?} in #t8 == null ?{self::Other} #t8 as{Unchecked} self::Other : #t8{self::Other};
           #t1 = other.{self::Other::text}{core::String};
           break #L1;
         }
       }
       {
-        if(#0#0 is self::WrapperB && (#0#5#isSet ?{core::bool} #0#5{core::bool} : let final core::bool #t8 = #0#5#isSet = true in #0#5 = (#0#3#isSet ?{self::Other?} #0#3{self::Other?} : let final core::bool #t9 = #0#3#isSet = true in #0#3 = #0#0{self::WrapperB}.{self::WrapperB::inner}{self::Inner}.{self::Inner::other}{self::Other?}) == null)) {
+        if(#0#0 is self::WrapperB && (#0#5#isSet ?{core::bool} #0#5{core::bool} : let final core::bool #t10 = #0#5#isSet = true in #0#5 = (#0#3#isSet ?{self::Other?} #0#3{self::Other?} : let final core::bool #t11 = #0#3#isSet = true in #0#3 = #0#0{self::WrapperB}.{self::WrapperB::inner}{self::Inner}.{self::Inner::other}{self::Other?}) == null)) {
           #t1 = "no other";
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/list_pattern_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/list_pattern_inside_cast.dart.weak.transformed.expect
index a27a12ddc9d..379cd08e296 100644
--- a/pkg/front_end/testcases/patterns/list_pattern_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/list_pattern_inside_cast.dart.weak.transformed.expect
@@ -7,7 +7,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in (#0#0 as{Unchecked} core::Object) is core::List<core::Object?> && ((#0#0 as{Unchecked} core::Object) as{Unchecked} core::List<core::Object?>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && #C1 =={core::num::==}{(core::Object) → core::bool} ((#0#0 as{Unchecked} core::Object) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object}) is core::List<core::Object?> && ((let dynamic #t4 = #0#0 in #t4 == null ?{core::Object} #t4 as core::Object : #t4{core::Object}) as{Unchecked} core::List<core::Object?>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && #C1 =={core::num::==}{(core::Object) → core::bool} ((let dynamic #t5 = #0#0 in #t5 == null ?{core::Object} #t5 as core::Object : #t5{core::Object}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/list_pattern_inside_if_case.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/list_pattern_inside_if_case.dart.weak.transformed.expect
index d6481257288..baa989a5abd 100644
--- a/pkg/front_end/testcases/patterns/list_pattern_inside_if_case.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/list_pattern_inside_if_case.dart.weak.transformed.expect
@@ -16,7 +16,7 @@ static method test1(dynamic x) → dynamic {
     {
       hoisted core::String? a;
       hoisted core::String b;
-      if(#1#0 is core::List<core::String?> && #1#0{core::List<core::String?>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && (let final core::String? #t1 = a = #1#0{core::List<core::String?>}.{core::List::[]}(0){(core::int) → core::String?} in true) && (!((#1#7#isSet ?{core::String?} #1#7{core::String?} : let final core::bool #t2 = #1#7#isSet = true in #1#7 = #1#0{core::List<core::String?>}.{core::List::[]}(1){(core::int) → core::String?}) == null) && (((#1#7#isSet ?{core::String?} #1#7{core::String?} : let final core::bool #t3 = #1#7#isSet = true in #1#7 = #1#0{core::List<core::String?>}.{core::List::[]}(1){(core::int) → core::String?}) as{Unchecked} core::String) is core::String && (let final core::String #t4 = b = (#1#7#isSet ?{core::String?} #1#7{core::String?} : let final core::bool #t5 = #1#7#isSet = true in #1#7 = #1#0{core::List<core::String?>}.{core::List::[]}(1){(core::int) → core::String?}) as{Unchecked} core::String in true))) && #1#0{core::List<core::String?>}.{core::List::[]}(2){(core::int) → core::String?} =={core::String::==}{(core::Object) → core::bool} #C4) {
+      if(#1#0 is core::List<core::String?> && #1#0{core::List<core::String?>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && (let final core::String? #t1 = a = #1#0{core::List<core::String?>}.{core::List::[]}(0){(core::int) → core::String?} in true) && (!((#1#7#isSet ?{core::String?} #1#7{core::String?} : let final core::bool #t2 = #1#7#isSet = true in #1#7 = #1#0{core::List<core::String?>}.{core::List::[]}(1){(core::int) → core::String?}) == null) && ((let core::String? #t3 = #1#7#isSet ?{core::String?} #1#7{core::String?} : let final core::bool #t4 = #1#7#isSet = true in #1#7 = #1#0{core::List<core::String?>}.{core::List::[]}(1){(core::int) → core::String?} in #t3 == null ?{core::String} #t3 as{Unchecked} core::String : #t3{core::String}) is core::String && (let final core::String #t5 = b = let core::String? #t6 = #1#7#isSet ?{core::String?} #1#7{core::String?} : let final core::bool #t7 = #1#7#isSet = true in #1#7 = #1#0{core::List<core::String?>}.{core::List::[]}(1){(core::int) → core::String?} in #t6 == null ?{core::String} #t6 as{Unchecked} core::String : #t6{core::String} in true))) && #1#0{core::List<core::String?>}.{core::List::[]}(2){(core::int) → core::String?} =={core::String::==}{(core::Object) → core::bool} #C4) {
         return 1;
       }
     }
@@ -30,7 +30,7 @@ static method test1(dynamic x) → dynamic {
     {
       hoisted core::String a;
       hoisted core::String? b;
-      if(#2#0 is core::List<dynamic> && #2#0{core::List<dynamic>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C3 && ((#2#6#isSet ?{dynamic} #2#6{dynamic} : let final core::bool #t6 = #2#6#isSet = true in #2#6 = #2#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) is core::List<core::String?> && ((#2#6#isSet ?{dynamic} #2#6{dynamic} : let final core::bool #t7 = #2#6#isSet = true in #2#6 = #2#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<core::String?>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C3 && (!((#2#11#isSet ?{core::String?} #2#11{core::String?} : let final core::bool #t8 = #2#11#isSet = true in #2#11 = ((#2#6#isSet ?{dynamic} #2#6{dynamic} : let final core::bool #t9 = #2#6#isSet = true in #2#6 = #2#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<core::String?>).{core::List::[]}(0){(core::int) → core::String?}) == null) && (let final core::String #t10 = a = (#2#11#isSet ?{core::String?} #2#11{core::String?} : let final core::bool #t11 = #2#11#isSet = true in #2#11 = ((#2#6#isSet ?{dynamic} #2#6{dynamic} : let final core::bool #t12 = #2#6#isSet = true in #2#6 = #2#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<core::String?>).{core::List::[]}(0){(core::int) → core::String?}) as{Unchecked} core::String in true)) && (let final core::String? #t13 = b = ((#2#6#isSet ?{dynamic} #2#6{dynamic} : let final core::bool #t14 = #2#6#isSet = true in #2#6 = #2#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<core::String?>).{core::List::[]}(1){(core::int) → core::String?} in true)) && #C5 =={core::num::==}{(core::Object) → core::bool} #2#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) {
+      if(#2#0 is core::List<dynamic> && #2#0{core::List<dynamic>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C3 && ((#2#6#isSet ?{dynamic} #2#6{dynamic} : let final core::bool #t8 = #2#6#isSet = true in #2#6 = #2#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) is core::List<core::String?> && ((#2#6#isSet ?{dynamic} #2#6{dynamic} : let final core::bool #t9 = #2#6#isSet = true in #2#6 = #2#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<core::String?>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C3 && (!((#2#11#isSet ?{core::String?} #2#11{core::String?} : let final core::bool #t10 = #2#11#isSet = true in #2#11 = ((#2#6#isSet ?{dynamic} #2#6{dynamic} : let final core::bool #t11 = #2#6#isSet = true in #2#6 = #2#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<core::String?>).{core::List::[]}(0){(core::int) → core::String?}) == null) && (let final core::String #t12 = a = let core::String? #t13 = #2#11#isSet ?{core::String?} #2#11{core::String?} : let final core::bool #t14 = #2#11#isSet = true in #2#11 = ((#2#6#isSet ?{dynamic} #2#6{dynamic} : let final core::bool #t15 = #2#6#isSet = true in #2#6 = #2#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<core::String?>).{core::List::[]}(0){(core::int) → core::String?} in #t13 == null ?{core::String} #t13 as{Unchecked} core::String : #t13{core::String} in true)) && (let final core::String? #t16 = b = ((#2#6#isSet ?{dynamic} #2#6{dynamic} : let final core::bool #t17 = #2#6#isSet = true in #2#6 = #2#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<core::String?>).{core::List::[]}(1){(core::int) → core::String?} in true)) && #C5 =={core::num::==}{(core::Object) → core::bool} #2#0{core::List<dynamic>}.{core::List::[]}(1){(core::int) → dynamic}) {
         return 2;
       }
     }
@@ -45,8 +45,8 @@ static method test1(dynamic x) → dynamic {
     synthesized core::bool #3#16#isSet = false;
     {
       hoisted dynamic a;
-      if(#3#0 is core::List<dynamic> && #3#0{core::List<dynamic>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C2 && ((#3#6#isSet ?{dynamic} #3#6{dynamic} : let final core::bool #t15 = #3#6#isSet = true in #3#6 = #3#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) is core::List<dynamic> && ((#3#6#isSet ?{dynamic} #3#6{dynamic} : let final core::bool #t16 = #3#6#isSet = true in #3#6 = #3#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C2 && ((#3#11#isSet ?{dynamic} #3#11{dynamic} : let final core::bool #t17 = #3#11#isSet = true in #3#11 = ((#3#6#isSet ?{dynamic} #3#6{dynamic} : let final core::bool #t18 = #3#6#isSet = true in #3#6 = #3#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::[]}(0){(core::int) → dynamic}) is core::List<dynamic> && ((#3#11#isSet ?{dynamic} #3#11{dynamic} : let final core::bool #t19 = #3#11#isSet = true in #3#11 = ((#3#6#isSet ?{dynamic} #3#6{dynamic} : let final core::bool #t20 = #3#6#isSet = true in #3#6 = #3#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C2 && !((#3#16#isSet ?{dynamic} #3#16{dynamic} : let final core::bool #t21 = #3#16#isSet = true in #3#16 = ((#3#11#isSet ?{dynamic} #3#11{dynamic} : let final core::bool #t22 = #3#11#isSet = true in #3#11 = ((#3#6#isSet ?{dynamic} #3#6{dynamic} : let final core::bool #t23 = #3#6#isSet = true in #3#6 = #3#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::[]}(0){(core::int) → dynamic}) == null)))) {
-        a = #3#16#isSet ?{dynamic} #3#16{dynamic} : let final core::bool #t24 = #3#16#isSet = true in #3#16 = ((#3#11#isSet ?{dynamic} #3#11{dynamic} : let final core::bool #t25 = #3#11#isSet = true in #3#11 = ((#3#6#isSet ?{dynamic} #3#6{dynamic} : let final core::bool #t26 = #3#6#isSet = true in #3#6 = #3#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::[]}(0){(core::int) → dynamic};
+      if(#3#0 is core::List<dynamic> && #3#0{core::List<dynamic>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C2 && ((#3#6#isSet ?{dynamic} #3#6{dynamic} : let final core::bool #t18 = #3#6#isSet = true in #3#6 = #3#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) is core::List<dynamic> && ((#3#6#isSet ?{dynamic} #3#6{dynamic} : let final core::bool #t19 = #3#6#isSet = true in #3#6 = #3#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C2 && ((#3#11#isSet ?{dynamic} #3#11{dynamic} : let final core::bool #t20 = #3#11#isSet = true in #3#11 = ((#3#6#isSet ?{dynamic} #3#6{dynamic} : let final core::bool #t21 = #3#6#isSet = true in #3#6 = #3#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::[]}(0){(core::int) → dynamic}) is core::List<dynamic> && ((#3#11#isSet ?{dynamic} #3#11{dynamic} : let final core::bool #t22 = #3#11#isSet = true in #3#11 = ((#3#6#isSet ?{dynamic} #3#6{dynamic} : let final core::bool #t23 = #3#6#isSet = true in #3#6 = #3#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C2 && !((#3#16#isSet ?{dynamic} #3#16{dynamic} : let final core::bool #t24 = #3#16#isSet = true in #3#16 = ((#3#11#isSet ?{dynamic} #3#11{dynamic} : let final core::bool #t25 = #3#11#isSet = true in #3#11 = ((#3#6#isSet ?{dynamic} #3#6{dynamic} : let final core::bool #t26 = #3#6#isSet = true in #3#6 = #3#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::[]}(0){(core::int) → dynamic}) == null)))) {
+        a = #3#16#isSet ?{dynamic} #3#16{dynamic} : let final core::bool #t27 = #3#16#isSet = true in #3#16 = ((#3#11#isSet ?{dynamic} #3#11{dynamic} : let final core::bool #t28 = #3#11#isSet = true in #3#11 = ((#3#6#isSet ?{dynamic} #3#6{dynamic} : let final core::bool #t29 = #3#6#isSet = true in #3#6 = #3#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::[]}(0){(core::int) → dynamic}) as{Unchecked} core::List<dynamic>).{core::List::[]}(0){(core::int) → dynamic};
         {
           return 3;
         }
@@ -74,7 +74,7 @@ static method test2(core::List<core::Object?> x) → dynamic {
     {
       hoisted core::String? a;
       hoisted core::String b;
-      if(#1#0 is core::List<core::String?> && #1#0{core::List<core::String?>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && (let final core::String? #t27 = a = #1#0{core::List<core::String?>}.{core::List::[]}(0){(core::int) → core::String?} in true) && (!((#1#7#isSet ?{core::String?} #1#7{core::String?} : let final core::bool #t28 = #1#7#isSet = true in #1#7 = #1#0{core::List<core::String?>}.{core::List::[]}(1){(core::int) → core::String?}) == null) && (((#1#7#isSet ?{core::String?} #1#7{core::String?} : let final core::bool #t29 = #1#7#isSet = true in #1#7 = #1#0{core::List<core::String?>}.{core::List::[]}(1){(core::int) → core::String?}) as{Unchecked} core::String) is core::String && (let final core::String #t30 = b = (#1#7#isSet ?{core::String?} #1#7{core::String?} : let final core::bool #t31 = #1#7#isSet = true in #1#7 = #1#0{core::List<core::String?>}.{core::List::[]}(1){(core::int) → core::String?}) as{Unchecked} core::String in true))) && #1#0{core::List<core::String?>}.{core::List::[]}(2){(core::int) → core::String?} =={core::String::==}{(core::Object) → core::bool} #C4) {
+      if(#1#0 is core::List<core::String?> && #1#0{core::List<core::String?>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && (let final core::String? #t30 = a = #1#0{core::List<core::String?>}.{core::List::[]}(0){(core::int) → core::String?} in true) && (!((#1#7#isSet ?{core::String?} #1#7{core::String?} : let final core::bool #t31 = #1#7#isSet = true in #1#7 = #1#0{core::List<core::String?>}.{core::List::[]}(1){(core::int) → core::String?}) == null) && ((let core::String? #t32 = #1#7#isSet ?{core::String?} #1#7{core::String?} : let final core::bool #t33 = #1#7#isSet = true in #1#7 = #1#0{core::List<core::String?>}.{core::List::[]}(1){(core::int) → core::String?} in #t32 == null ?{core::String} #t32 as{Unchecked} core::String : #t32{core::String}) is core::String && (let final core::String #t34 = b = let core::String? #t35 = #1#7#isSet ?{core::String?} #1#7{core::String?} : let final core::bool #t36 = #1#7#isSet = true in #1#7 = #1#0{core::List<core::String?>}.{core::List::[]}(1){(core::int) → core::String?} in #t35 == null ?{core::String} #t35 as{Unchecked} core::String : #t35{core::String} in true))) && #1#0{core::List<core::String?>}.{core::List::[]}(2){(core::int) → core::String?} =={core::String::==}{(core::Object) → core::bool} #C4) {
         return 1;
       }
     }
@@ -88,7 +88,7 @@ static method test2(core::List<core::Object?> x) → dynamic {
     {
       hoisted core::String a;
       hoisted core::String? b;
-      if(#2#0.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C3 && ((#2#4#isSet ?{core::Object?} #2#4{core::Object?} : let final core::bool #t32 = #2#4#isSet = true in #2#4 = #2#0.{core::List::[]}(0){(core::int) → core::Object?}) is core::List<core::String?> && ((#2#4#isSet ?{core::Object?} #2#4{core::Object?} : let final core::bool #t33 = #2#4#isSet = true in #2#4 = #2#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::String?>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C3 && (!((#2#9#isSet ?{core::String?} #2#9{core::String?} : let final core::bool #t34 = #2#9#isSet = true in #2#9 = ((#2#4#isSet ?{core::Object?} #2#4{core::Object?} : let final core::bool #t35 = #2#4#isSet = true in #2#4 = #2#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::String?>).{core::List::[]}(0){(core::int) → core::String?}) == null) && (let final core::String #t36 = a = (#2#9#isSet ?{core::String?} #2#9{core::String?} : let final core::bool #t37 = #2#9#isSet = true in #2#9 = ((#2#4#isSet ?{core::Object?} #2#4{core::Object?} : let final core::bool #t38 = #2#4#isSet = true in #2#4 = #2#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::String?>).{core::List::[]}(0){(core::int) → core::String?}) as{Unchecked} core::String in true)) && (let final core::String? #t39 = b = ((#2#4#isSet ?{core::Object?} #2#4{core::Object?} : let final core::bool #t40 = #2#4#isSet = true in #2#4 = #2#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::String?>).{core::List::[]}(1){(core::int) → core::String?} in true)) && #C5 =={core::num::==}{(core::Object) → core::bool} #2#0.{core::List::[]}(1){(core::int) → core::Object?}) {
+      if(#2#0.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C3 && ((#2#4#isSet ?{core::Object?} #2#4{core::Object?} : let final core::bool #t37 = #2#4#isSet = true in #2#4 = #2#0.{core::List::[]}(0){(core::int) → core::Object?}) is core::List<core::String?> && ((#2#4#isSet ?{core::Object?} #2#4{core::Object?} : let final core::bool #t38 = #2#4#isSet = true in #2#4 = #2#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::String?>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C3 && (!((#2#9#isSet ?{core::String?} #2#9{core::String?} : let final core::bool #t39 = #2#9#isSet = true in #2#9 = ((#2#4#isSet ?{core::Object?} #2#4{core::Object?} : let final core::bool #t40 = #2#4#isSet = true in #2#4 = #2#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::String?>).{core::List::[]}(0){(core::int) → core::String?}) == null) && (let final core::String #t41 = a = let core::String? #t42 = #2#9#isSet ?{core::String?} #2#9{core::String?} : let final core::bool #t43 = #2#9#isSet = true in #2#9 = ((#2#4#isSet ?{core::Object?} #2#4{core::Object?} : let final core::bool #t44 = #2#4#isSet = true in #2#4 = #2#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::String?>).{core::List::[]}(0){(core::int) → core::String?} in #t42 == null ?{core::String} #t42 as{Unchecked} core::String : #t42{core::String} in true)) && (let final core::String? #t45 = b = ((#2#4#isSet ?{core::Object?} #2#4{core::Object?} : let final core::bool #t46 = #2#4#isSet = true in #2#4 = #2#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::String?>).{core::List::[]}(1){(core::int) → core::String?} in true)) && #C5 =={core::num::==}{(core::Object) → core::bool} #2#0.{core::List::[]}(1){(core::int) → core::Object?}) {
         return 2;
       }
     }
@@ -103,8 +103,8 @@ static method test2(core::List<core::Object?> x) → dynamic {
     synthesized core::bool #3#14#isSet = false;
     {
       hoisted core::Object a;
-      if(#3#0.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C2 && ((#3#4#isSet ?{core::Object?} #3#4{core::Object?} : let final core::bool #t41 = #3#4#isSet = true in #3#4 = #3#0.{core::List::[]}(0){(core::int) → core::Object?}) is core::List<core::Object?> && ((#3#4#isSet ?{core::Object?} #3#4{core::Object?} : let final core::bool #t42 = #3#4#isSet = true in #3#4 = #3#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C2 && ((#3#9#isSet ?{core::Object?} #3#9{core::Object?} : let final core::bool #t43 = #3#9#isSet = true in #3#9 = ((#3#4#isSet ?{core::Object?} #3#4{core::Object?} : let final core::bool #t44 = #3#4#isSet = true in #3#4 = #3#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) is core::List<core::Object?> && ((#3#9#isSet ?{core::Object?} #3#9{core::Object?} : let final core::bool #t45 = #3#9#isSet = true in #3#9 = ((#3#4#isSet ?{core::Object?} #3#4{core::Object?} : let final core::bool #t46 = #3#4#isSet = true in #3#4 = #3#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C2 && !((#3#14#isSet ?{core::Object?} #3#14{core::Object?} : let final core::bool #t47 = #3#14#isSet = true in #3#14 = ((#3#9#isSet ?{core::Object?} #3#9{core::Object?} : let final core::bool #t48 = #3#9#isSet = true in #3#9 = ((#3#4#isSet ?{core::Object?} #3#4{core::Object?} : let final core::bool #t49 = #3#4#isSet = true in #3#4 = #3#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) == null)))) {
-        a = (#3#14#isSet ?{core::Object?} #3#14{core::Object?} : let final core::bool #t50 = #3#14#isSet = true in #3#14 = ((#3#9#isSet ?{core::Object?} #3#9{core::Object?} : let final core::bool #t51 = #3#9#isSet = true in #3#9 = ((#3#4#isSet ?{core::Object?} #3#4{core::Object?} : let final core::bool #t52 = #3#4#isSet = true in #3#4 = #3#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::Object;
+      if(#3#0.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C2 && ((#3#4#isSet ?{core::Object?} #3#4{core::Object?} : let final core::bool #t47 = #3#4#isSet = true in #3#4 = #3#0.{core::List::[]}(0){(core::int) → core::Object?}) is core::List<core::Object?> && ((#3#4#isSet ?{core::Object?} #3#4{core::Object?} : let final core::bool #t48 = #3#4#isSet = true in #3#4 = #3#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C2 && ((#3#9#isSet ?{core::Object?} #3#9{core::Object?} : let final core::bool #t49 = #3#9#isSet = true in #3#9 = ((#3#4#isSet ?{core::Object?} #3#4{core::Object?} : let final core::bool #t50 = #3#4#isSet = true in #3#4 = #3#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) is core::List<core::Object?> && ((#3#9#isSet ?{core::Object?} #3#9{core::Object?} : let final core::bool #t51 = #3#9#isSet = true in #3#9 = ((#3#4#isSet ?{core::Object?} #3#4{core::Object?} : let final core::bool #t52 = #3#4#isSet = true in #3#4 = #3#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C2 && !((#3#14#isSet ?{core::Object?} #3#14{core::Object?} : let final core::bool #t53 = #3#14#isSet = true in #3#14 = ((#3#9#isSet ?{core::Object?} #3#9{core::Object?} : let final core::bool #t54 = #3#9#isSet = true in #3#9 = ((#3#4#isSet ?{core::Object?} #3#4{core::Object?} : let final core::bool #t55 = #3#4#isSet = true in #3#4 = #3#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) == null)))) {
+        a = let core::Object? #t56 = #3#14#isSet ?{core::Object?} #3#14{core::Object?} : let final core::bool #t57 = #3#14#isSet = true in #3#14 = ((#3#9#isSet ?{core::Object?} #3#9{core::Object?} : let final core::bool #t58 = #3#9#isSet = true in #3#9 = ((#3#4#isSet ?{core::Object?} #3#4{core::Object?} : let final core::bool #t59 = #3#4#isSet = true in #3#4 = #3#0.{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?}) as{Unchecked} core::List<core::Object?>).{core::List::[]}(0){(core::int) → core::Object?} in #t56 == null ?{core::Object} #t56 as{Unchecked} core::Object : #t56{core::Object};
         {
           return 3;
         }
diff --git a/pkg/front_end/testcases/patterns/map_lookup.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/map_lookup.dart.weak.transformed.expect
index ce9d4a7fc42..2e07a05ed66 100644
--- a/pkg/front_end/testcases/patterns/map_lookup.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/map_lookup.dart.weak.transformed.expect
@@ -68,14 +68,14 @@ static method test1(core::Object o) → core::String {
     synthesized core::int? #0#9;
     synthesized core::bool #0#9#isSet = false;
     {
-      if(#0#0 is core::Map<core::String, core::int> && (#0#3#isSet ?{core::bool} #0#3{core::bool} : let final core::bool #t1 = #0#3#isSet = true in #0#3 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && (#0#6#isSet ?{core::bool} #0#6{core::bool} : let final core::bool #t2 = #0#6#isSet = true in #0#6 = #C6 =={core::num::==}{(core::Object) → core::bool} #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C5){(core::Object?) → core::int?} as{Unchecked} core::int) && (#0#8#isSet ?{core::bool} #0#8{core::bool} : let final core::bool #t3 = #0#8#isSet = true in #0#8 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#9#isSet ?{core::int?} #0#9{core::int?} : let final core::bool #t4 = #0#9#isSet = true in #0#9 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C7){(core::Object?) → core::int?}) as{Unchecked} core::int) {
+      if(#0#0 is core::Map<core::String, core::int> && (#0#3#isSet ?{core::bool} #0#3{core::bool} : let final core::bool #t1 = #0#3#isSet = true in #0#3 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && (#0#6#isSet ?{core::bool} #0#6{core::bool} : let final core::bool #t2 = #0#6#isSet = true in #0#6 = #C6 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t3 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C5){(core::Object?) → core::int?} in #t3 == null ?{core::int} #t3 as{Unchecked} core::int : #t3{core::int})) && (#0#8#isSet ?{core::bool} #0#8{core::bool} : let final core::bool #t4 = #0#8#isSet = true in #0#8 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t5 = #0#9#isSet ?{core::int?} #0#9{core::int?} : let final core::bool #t6 = #0#9#isSet = true in #0#9 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C7){(core::Object?) → core::int?} in #t5 == null ?{core::int} #t5 as{Unchecked} core::int : #t5{core::int})) {
         {
           return "match-2";
         }
       }
     }
     {
-      if(#0#0 is core::Map<core::String, core::int> && (#0#3#isSet ?{core::bool} #0#3{core::bool} : let final core::bool #t5 = #0#3#isSet = true in #0#3 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && (#0#6#isSet ?{core::bool} #0#6{core::bool} : let final core::bool #t6 = #0#6#isSet = true in #0#6 = #C6 =={core::num::==}{(core::Object) → core::bool} #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C5){(core::Object?) → core::int?} as{Unchecked} core::int) && (#0#8#isSet ?{core::bool} #0#8{core::bool} : let final core::bool #t7 = #0#8#isSet = true in #0#8 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool}) && #C9 =={core::num::==}{(core::Object) → core::bool} (#0#9#isSet ?{core::int?} #0#9{core::int?} : let final core::bool #t8 = #0#9#isSet = true in #0#9 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C7){(core::Object?) → core::int?}) as{Unchecked} core::int) {
+      if(#0#0 is core::Map<core::String, core::int> && (#0#3#isSet ?{core::bool} #0#3{core::bool} : let final core::bool #t7 = #0#3#isSet = true in #0#3 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && (#0#6#isSet ?{core::bool} #0#6{core::bool} : let final core::bool #t8 = #0#6#isSet = true in #0#6 = #C6 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t9 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C5){(core::Object?) → core::int?} in #t9 == null ?{core::int} #t9 as{Unchecked} core::int : #t9{core::int})) && (#0#8#isSet ?{core::bool} #0#8{core::bool} : let final core::bool #t10 = #0#8#isSet = true in #0#8 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool}) && #C9 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t11 = #0#9#isSet ?{core::int?} #0#9{core::int?} : let final core::bool #t12 = #0#9#isSet = true in #0#9 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C7){(core::Object?) → core::int?} in #t11 == null ?{core::int} #t11 as{Unchecked} core::int : #t11{core::int})) {
         {
           return "match-3";
         }
@@ -92,7 +92,7 @@ static method test1(core::Object o) → core::String {
 }
 static method test2(core::Object o) → core::String
   return block {
-    core::String #t9;
+    core::String #t13;
     final synthesized core::Object #0#0 = o;
     synthesized core::bool #0#3;
     synthesized core::bool #0#3#isSet = false;
@@ -105,26 +105,26 @@ static method test2(core::Object o) → core::String
     #L2:
     {
       {
-        if(#0#0 is core::Map<core::String, core::int> && (#0#3#isSet ?{core::bool} #0#3{core::bool} : let final core::bool #t10 = #0#3#isSet = true in #0#3 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && (#0#6#isSet ?{core::bool} #0#6{core::bool} : let final core::bool #t11 = #0#6#isSet = true in #0#6 = #C6 =={core::num::==}{(core::Object) → core::bool} #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C5){(core::Object?) → core::int?} as{Unchecked} core::int) && (#0#8#isSet ?{core::bool} #0#8{core::bool} : let final core::bool #t12 = #0#8#isSet = true in #0#8 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#9#isSet ?{core::int?} #0#9{core::int?} : let final core::bool #t13 = #0#9#isSet = true in #0#9 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C7){(core::Object?) → core::int?}) as{Unchecked} core::int) {
-          #t9 = "match-2";
+        if(#0#0 is core::Map<core::String, core::int> && (#0#3#isSet ?{core::bool} #0#3{core::bool} : let final core::bool #t14 = #0#3#isSet = true in #0#3 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && (#0#6#isSet ?{core::bool} #0#6{core::bool} : let final core::bool #t15 = #0#6#isSet = true in #0#6 = #C6 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t16 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C5){(core::Object?) → core::int?} in #t16 == null ?{core::int} #t16 as{Unchecked} core::int : #t16{core::int})) && (#0#8#isSet ?{core::bool} #0#8{core::bool} : let final core::bool #t17 = #0#8#isSet = true in #0#8 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t18 = #0#9#isSet ?{core::int?} #0#9{core::int?} : let final core::bool #t19 = #0#9#isSet = true in #0#9 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C7){(core::Object?) → core::int?} in #t18 == null ?{core::int} #t18 as{Unchecked} core::int : #t18{core::int})) {
+          #t13 = "match-2";
           break #L2;
         }
       }
       {
-        if(#0#0 is core::Map<core::String, core::int> && (#0#3#isSet ?{core::bool} #0#3{core::bool} : let final core::bool #t14 = #0#3#isSet = true in #0#3 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && (#0#6#isSet ?{core::bool} #0#6{core::bool} : let final core::bool #t15 = #0#6#isSet = true in #0#6 = #C6 =={core::num::==}{(core::Object) → core::bool} #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C5){(core::Object?) → core::int?} as{Unchecked} core::int) && (#0#8#isSet ?{core::bool} #0#8{core::bool} : let final core::bool #t16 = #0#8#isSet = true in #0#8 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool}) && #C9 =={core::num::==}{(core::Object) → core::bool} (#0#9#isSet ?{core::int?} #0#9{core::int?} : let final core::bool #t17 = #0#9#isSet = true in #0#9 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C7){(core::Object?) → core::int?}) as{Unchecked} core::int) {
-          #t9 = "match-3";
+        if(#0#0 is core::Map<core::String, core::int> && (#0#3#isSet ?{core::bool} #0#3{core::bool} : let final core::bool #t20 = #0#3#isSet = true in #0#3 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && (#0#6#isSet ?{core::bool} #0#6{core::bool} : let final core::bool #t21 = #0#6#isSet = true in #0#6 = #C6 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t22 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C5){(core::Object?) → core::int?} in #t22 == null ?{core::int} #t22 as{Unchecked} core::int : #t22{core::int})) && (#0#8#isSet ?{core::bool} #0#8{core::bool} : let final core::bool #t23 = #0#8#isSet = true in #0#8 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C7){(core::Object?) → core::bool}) && #C9 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t24 = #0#9#isSet ?{core::int?} #0#9{core::int?} : let final core::bool #t25 = #0#9#isSet = true in #0#9 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C7){(core::Object?) → core::int?} in #t24 == null ?{core::int} #t24 as{Unchecked} core::int : #t24{core::int})) {
+          #t13 = "match-3";
           break #L2;
         }
       }
       {
         if(true) {
-          #t9 = "no match";
+          #t13 = "no match";
           break #L2;
         }
       }
       throw{for-error-handling} new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable type.");
     }
-  } =>#t9;
+  } =>#t13;
 static method main() → dynamic {
   final self::MyMap<core::String, core::int> map = new self::MyMap::•<core::String, core::int>(<core::String, core::int>{"key1": 1, "key2": 2});
   self::expect("match-3", self::test1(map));
@@ -137,7 +137,7 @@ static method main() → dynamic {
   hoisted has-declared-initializer core::int x2;
   {
     final synthesized self::MyMap<core::String, core::int> #0#0 = map;
-    if(!(#0#0.{self::MyMap::containsKey}(#C5){(core::Object?) → core::bool} && (let final core::int #t18 = x1 = #0#0.{self::MyMap::[]}(#C5){(core::Object?) → core::int?} as{Unchecked} core::int in true) && #0#0.{self::MyMap::containsKey}(#C7){(core::Object?) → core::bool} && (let final core::int #t19 = x2 = #0#0.{self::MyMap::[]}(#C7){(core::Object?) → core::int?} as{Unchecked} core::int in true)))
+    if(!(#0#0.{self::MyMap::containsKey}(#C5){(core::Object?) → core::bool} && (let final core::int #t26 = x1 = let core::int? #t27 = #0#0.{self::MyMap::[]}(#C5){(core::Object?) → core::int?} in #t27 == null ?{core::int} #t27 as{Unchecked} core::int : #t27{core::int} in true) && #0#0.{self::MyMap::containsKey}(#C7){(core::Object?) → core::bool} && (let final core::int #t28 = x2 = let core::int? #t29 = #0#0.{self::MyMap::[]}(#C7){(core::Object?) → core::int?} in #t29 == null ?{core::int} #t29 as{Unchecked} core::int : #t29{core::int} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
   self::expect(self::hasUnsoundNullSafety ?{core::String} self::unsoundResult : self::soundResult, map.{self::MyMap::log}{core::String});
@@ -146,7 +146,7 @@ static method main() → dynamic {
   final hoisted has-declared-initializer core::int y2;
   {
     final synthesized self::MyMap<core::String, core::int> #1#0 = map;
-    if(!(#1#0.{self::MyMap::containsKey}(#C5){(core::Object?) → core::bool} && (let final core::int #t20 = y1 = #1#0.{self::MyMap::[]}(#C5){(core::Object?) → core::int?} as{Unchecked} core::int in true) && #1#0.{self::MyMap::containsKey}(#C7){(core::Object?) → core::bool} && (let final core::int #t21 = y2 = #1#0.{self::MyMap::[]}(#C7){(core::Object?) → core::int?} as{Unchecked} core::int in true)))
+    if(!(#1#0.{self::MyMap::containsKey}(#C5){(core::Object?) → core::bool} && (let final core::int #t30 = y1 = let core::int? #t31 = #1#0.{self::MyMap::[]}(#C5){(core::Object?) → core::int?} in #t31 == null ?{core::int} #t31 as{Unchecked} core::int : #t31{core::int} in true) && #1#0.{self::MyMap::containsKey}(#C7){(core::Object?) → core::bool} && (let final core::int #t32 = y2 = let core::int? #t33 = #1#0.{self::MyMap::[]}(#C7){(core::Object?) → core::int?} in #t33 == null ?{core::int} #t33 as{Unchecked} core::int : #t33{core::int} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
   self::expect(self::hasUnsoundNullSafety ?{core::String} self::unsoundResult : self::soundResult, map.{self::MyMap::log}{core::String});
@@ -170,4 +170,4 @@ constants  {
 
 Extra constant evaluation status:
 Evaluated: IsExpression @ org-dartlang-testcase:///map_lookup.dart:9:49 -> BoolConstant(true)
-Extra constant evaluation: evaluated: 343, effectively constant: 1
+Extra constant evaluation: evaluated: 415, effectively constant: 1
diff --git a/pkg/front_end/testcases/patterns/map_pattern_inside_case_with_type_arguments.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/map_pattern_inside_case_with_type_arguments.dart.weak.transformed.expect
index deabbcd0fea..dfed9e3257b 100644
--- a/pkg/front_end/testcases/patterns/map_pattern_inside_case_with_type_arguments.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/map_pattern_inside_case_with_type_arguments.dart.weak.transformed.expect
@@ -7,7 +7,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(#0#0 is core::Map<core::String, core::int> && #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && #C2 =={core::num::==}{(core::Object) → core::bool} #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C1){(core::Object?) → core::int?} as{Unchecked} core::int && #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && #C4 =={core::num::==}{(core::Object) → core::bool} #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} as{Unchecked} core::int) {
+      if(#0#0 is core::Map<core::String, core::int> && #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && #C2 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t1 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C1){(core::Object?) → core::int?} in #t1 == null ?{core::int} #t1 as{Unchecked} core::int : #t1{core::int}) && #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C3){(core::Object?) → core::bool} && #C4 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t2 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C3){(core::Object?) → core::int?} in #t2 == null ?{core::int} #t2 as{Unchecked} core::int : #t2{core::int})) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/map_pattern_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/map_pattern_inside_cast.dart.weak.transformed.expect
index a5e30238911..13198b35091 100644
--- a/pkg/front_end/testcases/patterns/map_pattern_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/map_pattern_inside_cast.dart.weak.transformed.expect
@@ -7,7 +7,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in (#0#0 as{Unchecked} core::Object) is core::Map<core::Object?, core::Object?> && ((#0#0 as{Unchecked} core::Object) as{Unchecked} core::Map<core::Object?, core::Object?>).{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && #C2 =={core::num::==}{(core::Object) → core::bool} ((#0#0 as{Unchecked} core::Object) as{Unchecked} core::Map<core::Object?, core::Object?>).{core::Map::[]}(#C1){(core::Object?) → core::Object?}) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object}) is core::Map<core::Object?, core::Object?> && ((let dynamic #t4 = #0#0 in #t4 == null ?{core::Object} #t4 as core::Object : #t4{core::Object}) as{Unchecked} core::Map<core::Object?, core::Object?>).{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && #C2 =={core::num::==}{(core::Object) → core::bool} ((let dynamic #t5 = #0#0 in #t5 == null ?{core::Object} #t5 as core::Object : #t5{core::Object}) as{Unchecked} core::Map<core::Object?, core::Object?>).{core::Map::[]}(#C1){(core::Object?) → core::Object?}) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/map_pattern_inside_if_case.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/map_pattern_inside_if_case.dart.weak.transformed.expect
index db8218a4cb5..b342db00f5e 100644
--- a/pkg/front_end/testcases/patterns/map_pattern_inside_if_case.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/map_pattern_inside_if_case.dart.weak.transformed.expect
@@ -28,19 +28,19 @@ static method test2(dynamic x) → dynamic {
 static method test3(core::Map<core::bool, core::double> x) → dynamic {
   {
     final synthesized core::Map<core::bool, core::double> #0#0 = x;
-    if(#0#0.{core::Map::containsKey}(#C7){(core::Object?) → core::bool} && #C8 =={core::num::==}{(core::Object) → core::bool} #0#0.{core::Map::[]}(#C7){(core::Object?) → core::double?} as{Unchecked} core::double) {
+    if(#0#0.{core::Map::containsKey}(#C7){(core::Object?) → core::bool} && #C8 =={core::num::==}{(core::Object) → core::bool} (let core::double? #t1 = #0#0.{core::Map::[]}(#C7){(core::Object?) → core::double?} in #t1 == null ?{core::double} #t1 as{Unchecked} core::double : #t1{core::double})) {
     }
   }
   {
     final synthesized core::Map<core::bool, core::double> #1#0 = x;
-    if(#1#0.{core::Map::containsKey}(#C9){(core::Object?) → core::bool} && #C10 =={core::num::==}{(core::Object) → core::bool} #1#0.{core::Map::[]}(#C9){(core::Object?) → core::double?} as{Unchecked} core::double) {
+    if(#1#0.{core::Map::containsKey}(#C9){(core::Object?) → core::bool} && #C10 =={core::num::==}{(core::Object) → core::bool} (let core::double? #t2 = #1#0.{core::Map::[]}(#C9){(core::Object?) → core::double?} in #t2 == null ?{core::double} #t2 as{Unchecked} core::double : #t2{core::double})) {
     }
   }
 }
 static method test4(self::MyMap x) → dynamic {
   {
     final synthesized self::MyMap #0#0 = x;
-    if(#0#0.{core::Map::containsKey}(#C11){(core::Object?) → core::bool} && #C2 =={core::num::==}{(core::Object) → core::bool} #0#0.{core::Map::[]}(#C11){(core::Object?) → core::int?} as{Unchecked} core::int && #0#0.{core::Map::containsKey}(#C12){(core::Object?) → core::bool} && #C4 =={core::num::==}{(core::Object) → core::bool} #0#0.{core::Map::[]}(#C12){(core::Object?) → core::int?} as{Unchecked} core::int) {
+    if(#0#0.{core::Map::containsKey}(#C11){(core::Object?) → core::bool} && #C2 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t3 = #0#0.{core::Map::[]}(#C11){(core::Object?) → core::int?} in #t3 == null ?{core::int} #t3 as{Unchecked} core::int : #t3{core::int}) && #0#0.{core::Map::containsKey}(#C12){(core::Object?) → core::bool} && #C4 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t4 = #0#0.{core::Map::[]}(#C12){(core::Object?) → core::int?} in #t4 == null ?{core::int} #t4 as{Unchecked} core::int : #t4{core::int})) {
     }
   }
 }
@@ -52,7 +52,7 @@ static method test5(dynamic x) → dynamic {
     {
       hoisted dynamic y1;
       hoisted core::String y2;
-      if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C11){(core::Object?) → core::bool} && (let final dynamic #t1 = y1 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C11){(core::Object?) → dynamic} in true) && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C12){(core::Object?) → core::bool} && (let final dynamic #t2 = (#0#7#isSet ?{dynamic} #0#7{dynamic} : let final core::bool #t3 = #0#7#isSet = true in #0#7 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C12){(core::Object?) → dynamic})! in (#0#7#isSet ?{dynamic} #0#7{dynamic} : let final core::bool #t4 = #0#7#isSet = true in #0#7 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C12){(core::Object?) → dynamic})! is core::String && (let final core::String #t5 = y2 = (#0#7#isSet ?{dynamic} #0#7{dynamic} : let final core::bool #t6 = #0#7#isSet = true in #0#7 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C12){(core::Object?) → dynamic})! as{Unchecked} core::String in true))) {
+      if(#0#0 is core::Map<dynamic, dynamic> && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C11){(core::Object?) → core::bool} && (let final dynamic #t5 = y1 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C11){(core::Object?) → dynamic} in true) && #0#0{core::Map<dynamic, dynamic>}.{core::Map::containsKey}(#C12){(core::Object?) → core::bool} && (let final dynamic #t6 = (#0#7#isSet ?{dynamic} #0#7{dynamic} : let final core::bool #t7 = #0#7#isSet = true in #0#7 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C12){(core::Object?) → dynamic})! in (#0#7#isSet ?{dynamic} #0#7{dynamic} : let final core::bool #t8 = #0#7#isSet = true in #0#7 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C12){(core::Object?) → dynamic})! is core::String && (let final core::String #t9 = y2 = (#0#7#isSet ?{dynamic} #0#7{dynamic} : let final core::bool #t10 = #0#7#isSet = true in #0#7 = #0#0{core::Map<dynamic, dynamic>}.{core::Map::[]}(#C12){(core::Object?) → dynamic})! as{Unchecked} core::String in true))) {
         return 0;
       }
       else {
diff --git a/pkg/front_end/testcases/patterns/matching_and_capturing_accesses_list_element_once.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/matching_and_capturing_accesses_list_element_once.dart.weak.transformed.expect
index 764c2d91d94..c1fe7d44953 100644
--- a/pkg/front_end/testcases/patterns/matching_and_capturing_accesses_list_element_once.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/matching_and_capturing_accesses_list_element_once.dart.weak.transformed.expect
@@ -322,7 +322,7 @@ abstract class _A&Object&ListMixin extends core::Object implements col::ListBase
     }
   }
   method /* from org-dartlang-sdk:///sdk/lib/collection/list.dart */ fillRange(core::int start, core::int end, [covariant-by-class core::int? fill = #C2]) → void {
-    core::int value = let core::int? #t6 = fill in #t6 == null ?{core::int} #t6 as{Unchecked} core::int : #t6{core::int};
+    core::int value = let core::int? #t6 = fill in #t6 == null ?{core::int} let core::int? #t7 = #t6 in #t7 == null ?{core::int} #t7 as core::int : #t7{core::int} : #t6{core::int};
     core::RangeError::checkValidRange(start, end, this.{core::List::length}{core::int});
     for (core::int i = start; i.{core::num::<}(end){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
       this.{core::List::[]=}(i, value){(core::int, core::int) → void};
@@ -496,7 +496,7 @@ abstract class _A&Object&ListMixin extends core::Object implements col::ListBase
         for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
           core::int element = :sync-for-iterator.{core::Iterator::current}{core::int};
           {
-            this.{core::List::[]=}(let final core::int #t7 = index in let final core::int #t8 = index = #t7.{core::num::+}(1){(core::num) → core::int} in #t7, element){(core::int, core::int) → void};
+            this.{core::List::[]=}(let final core::int #t8 = index in let final core::int #t9 = index = #t8.{core::num::+}(1){(core::num) → core::int} in #t8, element){(core::int, core::int) → void};
           }
         }
       }
@@ -537,8 +537,8 @@ static method main() → dynamic {
     {
       hoisted core::int x;
       hoisted core::int y;
-      if(#0#0.{self::A::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C8 && ((#0#4#isSet ?{core::int} #0#4{core::int} : let final core::bool #t9 = #0#4#isSet = true in #0#4 = #0#0.{self::A::[]}(0){(core::int) → core::int}) is core::int && (let final core::int #t10 = x = #0#4#isSet ?{core::int} #0#4{core::int} : let final core::bool #t11 = #0#4#isSet = true in #0#4 = #0#0.{self::A::[]}(0){(core::int) → core::int} in true)) && (#0#5#isSet ?{core::int} #0#5{core::int} : let final core::bool #t12 = #0#5#isSet = true in #0#5 = #0#0.{self::A::[]}(1){(core::int) → core::int}) is core::int) {
-        y = #0#5#isSet ?{core::int} #0#5{core::int} : let final core::bool #t13 = #0#5#isSet = true in #0#5 = #0#0.{self::A::[]}(1){(core::int) → core::int};
+      if(#0#0.{self::A::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C8 && ((#0#4#isSet ?{core::int} #0#4{core::int} : let final core::bool #t10 = #0#4#isSet = true in #0#4 = #0#0.{self::A::[]}(0){(core::int) → core::int}) is core::int && (let final core::int #t11 = x = #0#4#isSet ?{core::int} #0#4{core::int} : let final core::bool #t12 = #0#4#isSet = true in #0#4 = #0#0.{self::A::[]}(0){(core::int) → core::int} in true)) && (#0#5#isSet ?{core::int} #0#5{core::int} : let final core::bool #t13 = #0#5#isSet = true in #0#5 = #0#0.{self::A::[]}(1){(core::int) → core::int}) is core::int) {
+        y = #0#5#isSet ?{core::int} #0#5{core::int} : let final core::bool #t14 = #0#5#isSet = true in #0#5 = #0#0.{self::A::[]}(1){(core::int) → core::int};
         {
           self::expectEquals(x, 0);
           self::expectEquals(y, 0);
@@ -570,4 +570,4 @@ Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart
 Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart:462:12 -> IntConstant(-1)
 Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart:471:12 -> IntConstant(-1)
 Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart:480:12 -> IntConstant(-1)
-Extra constant evaluation: evaluated: 1102, effectively constant: 4
+Extra constant evaluation: evaluated: 1108, effectively constant: 4
diff --git a/pkg/front_end/testcases/patterns/multiple_targets.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/multiple_targets.dart.weak.transformed.expect
index 5291d14bc9c..2d7b539339b 100644
--- a/pkg/front_end/testcases/patterns/multiple_targets.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/multiple_targets.dart.weak.transformed.expect
@@ -72,35 +72,35 @@ static method test(dynamic o) → dynamic {
       }
     }
     {
-      if(#0#0 is core::Map<core::String, core::int> && (#0#21#isSet ?{core::bool} #0#21{core::bool} : let final core::bool #t14 = #0#21#isSet = true in #0#21 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#22#isSet ?{core::int?} #0#22{core::int?} : let final core::bool #t15 = #0#22#isSet = true in #0#22 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C5){(core::Object?) → core::int?}) as{Unchecked} core::int) {
+      if(#0#0 is core::Map<core::String, core::int> && (#0#21#isSet ?{core::bool} #0#21{core::bool} : let final core::bool #t14 = #0#21#isSet = true in #0#21 = #0#0{core::Map<core::String, core::int>}.{core::Map::containsKey}(#C5){(core::Object?) → core::bool}) && #C8 =={core::num::==}{(core::Object) → core::bool} (let core::int? #t15 = #0#22#isSet ?{core::int?} #0#22{core::int?} : let final core::bool #t16 = #0#22#isSet = true in #0#22 = #0#0{core::Map<core::String, core::int>}.{core::Map::[]}(#C5){(core::Object?) → core::int?} in #t15 == null ?{core::int} #t15 as{Unchecked} core::int : #t15{core::int})) {
         {
           return 5;
         }
       }
     }
     {
-      if(#0#0 is self::A<dynamic> && #C6 =={core::num::==}{(core::Object) → core::bool} (#0#31#isSet ?{dynamic} #0#31{dynamic} : let final core::bool #t16 = #0#31#isSet = true in #0#31 = #0#0{self::A<dynamic>}.{self::A::foo}{dynamic})) {
+      if(#0#0 is self::A<dynamic> && #C6 =={core::num::==}{(core::Object) → core::bool} (#0#31#isSet ?{dynamic} #0#31{dynamic} : let final core::bool #t17 = #0#31#isSet = true in #0#31 = #0#0{self::A<dynamic>}.{self::A::foo}{dynamic})) {
         {
           return 6;
         }
       }
     }
     {
-      if(#0#0 is self::A<core::int> && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#31#isSet ?{core::int} #0#31{core::int} : let final core::bool #t17 = #0#31#isSet = true in #0#31 = #0#0{self::A<core::int>}.{self::A::foo}{core::int})) {
+      if(#0#0 is self::A<core::int> && #C7 =={core::num::==}{(core::Object) → core::bool} (#0#31#isSet ?{core::int} #0#31{core::int} : let final core::bool #t18 = #0#31#isSet = true in #0#31 = #0#0{self::A<core::int>}.{self::A::foo}{core::int})) {
         {
           return 7;
         }
       }
     }
     {
-      if(#0#0 is self::B && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#31#isSet ?{core::num} #0#31{core::num} : let final core::bool #t18 = #0#31#isSet = true in #0#31 = #0#0{self::B}.{self::B::foo}{core::num})) {
+      if(#0#0 is self::B && #C8 =={core::num::==}{(core::Object) → core::bool} (#0#31#isSet ?{core::num} #0#31{core::num} : let final core::bool #t19 = #0#31#isSet = true in #0#31 = #0#0{self::B}.{self::B::foo}{core::num})) {
         {
           return 8;
         }
       }
     }
     {
-      if(#0#0 is ({foo: core::Object?}) && #C9 =={core::num::==}{(core::Object) → core::bool} (#0#31#isSet ?{core::Object?} #0#31{core::Object?} : let final core::bool #t19 = #0#31#isSet = true in #0#31 = #0#0{({foo: core::Object?})}.foo{core::Object?})) {
+      if(#0#0 is ({foo: core::Object?}) && #C9 =={core::num::==}{(core::Object) → core::bool} (#0#31#isSet ?{core::Object?} #0#31{core::Object?} : let final core::bool #t20 = #0#31#isSet = true in #0#31 = #0#0{({foo: core::Object?})}.foo{core::Object?})) {
         {
           return 9;
         }
@@ -169,4 +169,4 @@ Evaluated: InstanceInvocation @ org-dartlang-testcase:///multiple_targets.dart:7
 Evaluated: RecordLiteral @ org-dartlang-testcase:///multiple_targets.dart:79:18 -> RecordConstant(const ({foo: 8}))
 Evaluated: InstanceInvocation @ org-dartlang-testcase:///multiple_targets.dart:80:10 -> IntConstant(-1)
 Evaluated: RecordLiteral @ org-dartlang-testcase:///multiple_targets.dart:80:19 -> RecordConstant(const ({foo: 9}))
-Extra constant evaluation: evaluated: 313, effectively constant: 11
+Extra constant evaluation: evaluated: 319, effectively constant: 11
diff --git a/pkg/front_end/testcases/patterns/negative_length.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/negative_length.dart.weak.transformed.expect
index 917f211f86b..c94b8f1251f 100644
--- a/pkg/front_end/testcases/patterns/negative_length.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/negative_length.dart.weak.transformed.expect
@@ -322,7 +322,7 @@ abstract class _NegativeLengthList&Object&ListMixin<E extends core::Object? = dy
     }
   }
   method /* from org-dartlang-sdk:///sdk/lib/collection/list.dart */ fillRange(core::int start, core::int end, [covariant-by-class self::_NegativeLengthList&Object&ListMixin::E? fill = #C2]) → void {
-    self::_NegativeLengthList&Object&ListMixin::E% value = let self::_NegativeLengthList&Object&ListMixin::E? #t6 = fill in #t6 == null ?{self::_NegativeLengthList&Object&ListMixin::E%} #t6 as{Unchecked} self::_NegativeLengthList&Object&ListMixin::E% : #t6{self::_NegativeLengthList&Object&ListMixin::E%};
+    self::_NegativeLengthList&Object&ListMixin::E% value = let self::_NegativeLengthList&Object&ListMixin::E? #t6 = fill in #t6 == null ?{self::_NegativeLengthList&Object&ListMixin::E%} let self::_NegativeLengthList&Object&ListMixin::E? #t7 = #t6 in #t7 == null ?{self::_NegativeLengthList&Object&ListMixin::E%} #t7 as self::_NegativeLengthList&Object&ListMixin::E% : #t7{self::_NegativeLengthList&Object&ListMixin::E%} : #t6{self::_NegativeLengthList&Object&ListMixin::E%};
     core::RangeError::checkValidRange(start, end, this.{core::List::length}{core::int});
     for (core::int i = start; i.{core::num::<}(end){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
       this.{core::List::[]=}(i, value){(core::int, self::_NegativeLengthList&Object&ListMixin::E%) → void};
@@ -496,7 +496,7 @@ abstract class _NegativeLengthList&Object&ListMixin<E extends core::Object? = dy
         for (; :sync-for-iterator.{core::Iterator::moveNext}(){() → core::bool}; ) {
           self::_NegativeLengthList&Object&ListMixin::E% element = :sync-for-iterator.{core::Iterator::current}{self::_NegativeLengthList&Object&ListMixin::E%};
           {
-            this.{core::List::[]=}(let final core::int #t7 = index in let final core::int #t8 = index = #t7.{core::num::+}(1){(core::num) → core::int} in #t7, element){(core::int, self::_NegativeLengthList&Object&ListMixin::E%) → void};
+            this.{core::List::[]=}(let final core::int #t8 = index in let final core::int #t9 = index = #t8.{core::num::+}(1){(core::num) → core::int} in #t8, element){(core::int, self::_NegativeLengthList&Object&ListMixin::E%) → void};
           }
         }
       }
@@ -530,33 +530,33 @@ class NegativeLengthList<E extends core::Object? = dynamic> extends self::_Negat
 }
 static method switchList(core::List<core::int> list) → core::int
   return block {
-    core::int #t9;
+    core::int #t10;
     final synthesized core::List<core::int> #0#0 = list;
     synthesized core::int #0#1;
     synthesized core::bool #0#1#isSet = false;
     #L1:
     {
       {
-        if((#0#1#isSet ?{core::int} #0#1{core::int} : let final core::bool #t10 = #0#1#isSet = true in #0#1 = #0#0.{core::List::length}{core::int}).{core::num::>=}(#C8){(core::num) → core::bool}) {
-          #t9 = 2;
+        if((#0#1#isSet ?{core::int} #0#1{core::int} : let final core::bool #t11 = #0#1#isSet = true in #0#1 = #0#0.{core::List::length}{core::int}).{core::num::>=}(#C8){(core::num) → core::bool}) {
+          #t10 = 2;
           break #L1;
         }
       }
       {
-        if((#0#1#isSet ?{core::int} #0#1{core::int} : let final core::bool #t11 = #0#1#isSet = true in #0#1 = #0#0.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C9) {
-          #t9 = 1;
+        if((#0#1#isSet ?{core::int} #0#1{core::int} : let final core::bool #t12 = #0#1#isSet = true in #0#1 = #0#0.{core::List::length}{core::int}) =={core::num::==}{(core::Object) → core::bool} #C9) {
+          #t10 = 1;
           break #L1;
         }
       }
       {
-        if((#0#1#isSet ?{core::int} #0#1{core::int} : let final core::bool #t12 = #0#1#isSet = true in #0#1 = #0#0.{core::List::length}{core::int}).{core::num::<=}(#C7){(core::num) → core::bool}) {
-          #t9 = 0;
+        if((#0#1#isSet ?{core::int} #0#1{core::int} : let final core::bool #t13 = #0#1#isSet = true in #0#1 = #0#0.{core::List::length}{core::int}).{core::num::<=}(#C7){(core::num) → core::bool}) {
+          #t10 = 0;
           break #L1;
         }
       }
       throw{for-error-handling} new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable type.");
     }
-  } =>#t9;
+  } =>#t10;
 static method main() → dynamic {
   self::expect(0, self::switchList(core::_GrowableList::•<core::int>(0)));
   self::expect(1, self::switchList(core::_GrowableList::_literal1<core::int>(0)));
@@ -588,4 +588,4 @@ Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart
 Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart:471:12 -> IntConstant(-1)
 Evaluated: InstanceInvocation @ org-dartlang-sdk:///sdk/lib/collection/list.dart:480:12 -> IntConstant(-1)
 Evaluated: InstanceInvocation @ org-dartlang-testcase:///negative_length.dart:12:41 -> IntConstant(-1)
-Extra constant evaluation: evaluated: 1124, effectively constant: 5
+Extra constant evaluation: evaluated: 1130, effectively constant: 5
diff --git a/pkg/front_end/testcases/patterns/non_constant_pattern_in_if.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/non_constant_pattern_in_if.dart.weak.transformed.expect
index 8b1668877f7..5292ddbc3d4 100644
--- a/pkg/front_end/testcases/patterns/non_constant_pattern_in_if.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/non_constant_pattern_in_if.dart.weak.transformed.expect
@@ -58,7 +58,7 @@ static method test(dynamic value, core::bool expected) → void {
   }
   {
     final synthesized dynamic #3#0 = value;
-    if(#3#0 is core::Map<core::num, core::Object> && #3#0{core::Map<core::num, core::Object>}.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && #C4 =={core::String::==}{(core::Object) → core::bool} #3#0{core::Map<core::num, core::Object>}.{core::Map::[]}(#C1){(core::Object?) → core::Object?} as{Unchecked} core::Object) {
+    if(#3#0 is core::Map<core::num, core::Object> && #3#0{core::Map<core::num, core::Object>}.{core::Map::containsKey}(#C1){(core::Object?) → core::bool} && #C4 =={core::String::==}{(core::Object) → core::bool} (let core::Object? #t1 = #3#0{core::Map<core::num, core::Object>}.{core::Map::[]}(#C1){(core::Object?) → core::Object?} in #t1 == null ?{core::Object} #t1 as{Unchecked} core::Object : #t1{core::Object})) {
       matched = true;
     }
   }
diff --git a/pkg/front_end/testcases/patterns/non_constant_pattern_in_switch.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/non_constant_pattern_in_switch.dart.weak.transformed.expect
index 1e0668bc4a6..54d98e46fc3 100644
--- a/pkg/front_end/testcases/patterns/non_constant_pattern_in_switch.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/non_constant_pattern_in_switch.dart.weak.transformed.expect
@@ -74,7 +74,7 @@ static method test(dynamic value, core::bool expected) → void {
       }
     }
     {
-      if(#0#0 is core::Map<core::num, core::Object> && (#0#12#isSet ?{core::bool} #0#12{core::bool} : let final core::bool #t7 = #0#12#isSet = true in #0#12 = #0#0{core::Map<core::num, core::Object>}.{core::Map::containsKey}(#C1){(core::Object?) → core::bool}) && (#0#15#isSet ?{core::bool} #0#15{core::bool} : let final core::bool #t8 = #0#15#isSet = true in #0#15 = #C4 =={core::String::==}{(core::Object) → core::bool} #0#0{core::Map<core::num, core::Object>}.{core::Map::[]}(#C1){(core::Object?) → core::Object?} as{Unchecked} core::Object)) {
+      if(#0#0 is core::Map<core::num, core::Object> && (#0#12#isSet ?{core::bool} #0#12{core::bool} : let final core::bool #t7 = #0#12#isSet = true in #0#12 = #0#0{core::Map<core::num, core::Object>}.{core::Map::containsKey}(#C1){(core::Object?) → core::bool}) && (#0#15#isSet ?{core::bool} #0#15{core::bool} : let final core::bool #t8 = #0#15#isSet = true in #0#15 = #C4 =={core::String::==}{(core::Object) → core::bool} (let core::Object? #t9 = #0#0{core::Map<core::num, core::Object>}.{core::Map::[]}(#C1){(core::Object?) → core::Object?} in #t9 == null ?{core::Object} #t9 as{Unchecked} core::Object : #t9{core::Object}))) {
         {
           matched = true;
           break #L1;
diff --git a/pkg/front_end/testcases/patterns/null_check_inside_extractor_pattern_implicitly_named.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/null_check_inside_extractor_pattern_implicitly_named.dart.weak.transformed.expect
index 58323992c72..df30b1e5783 100644
--- a/pkg/front_end/testcases/patterns/null_check_inside_extractor_pattern_implicitly_named.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/null_check_inside_extractor_pattern_implicitly_named.dart.weak.transformed.expect
@@ -16,7 +16,7 @@ static method test(dynamic x) → dynamic {
     synthesized core::bool #0#2#isSet = false;
     {
       hoisted core::int f;
-      if(#0#0 is self::C && (!((#0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t1 = #0#2#isSet = true in #0#2 = #0#0{self::C}.{self::C::f}{core::int?}) == null) && (let final core::int #t2 = f = (#0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t3 = #0#2#isSet = true in #0#2 = #0#0{self::C}.{self::C::f}{core::int?}) as{Unchecked} core::int in true))) {
+      if(#0#0 is self::C && (!((#0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t1 = #0#2#isSet = true in #0#2 = #0#0{self::C}.{self::C::f}{core::int?}) == null) && (let final core::int #t2 = f = let core::int? #t3 = #0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t4 = #0#2#isSet = true in #0#2 = #0#0{self::C}.{self::C::f}{core::int?} in #t3 == null ?{core::int} #t3 as{Unchecked} core::int : #t3{core::int} in true))) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/null_literal_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/null_literal_inside_cast.dart.weak.transformed.expect
index 7b821436347..d36d692ff83 100644
--- a/pkg/front_end/testcases/patterns/null_literal_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/null_literal_inside_cast.dart.weak.transformed.expect
@@ -7,7 +7,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in #0#0 as{Unchecked} core::Object == null) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object}) == null) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/parenthesized_pattern_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/parenthesized_pattern_inside_cast.dart.weak.transformed.expect
index 2bc5772600b..e18431c736b 100644
--- a/pkg/front_end/testcases/patterns/parenthesized_pattern_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/parenthesized_pattern_inside_cast.dart.weak.transformed.expect
@@ -7,7 +7,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in #C1 =={core::num::==}{(core::Object) → core::bool} #0#0 as{Unchecked} core::Object) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in #C1 =={core::num::==}{(core::Object) → core::bool} (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object})) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/parser_recovery_in_pattern_arguments.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/parser_recovery_in_pattern_arguments.dart.weak.transformed.expect
index a9d38a4d57b..3f469744985 100644
--- a/pkg/front_end/testcases/patterns/parser_recovery_in_pattern_arguments.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/parser_recovery_in_pattern_arguments.dart.weak.transformed.expect
@@ -36,9 +36,9 @@ static method test() → dynamic {
              ^";
     if(!(#0#0.{core::Map::containsKey}(invalid-expression "pkg/front_end/testcases/patterns/parser_recovery_in_pattern_arguments.dart:13:14: Error: This couldn't be parsed.
   var {const C(:var t): a1} = foo();
-             ^"){(core::Object?) → core::bool} && (let final core::int #t1 = a1 = #0#0.{core::Map::[]}(invalid-expression "pkg/front_end/testcases/patterns/parser_recovery_in_pattern_arguments.dart:13:14: Error: This couldn't be parsed.
+             ^"){(core::Object?) → core::bool} && (let final core::int #t1 = a1 = let core::int? #t2 = #0#0.{core::Map::[]}(invalid-expression "pkg/front_end/testcases/patterns/parser_recovery_in_pattern_arguments.dart:13:14: Error: This couldn't be parsed.
   var {const C(:var t): a1} = foo();
-             ^"){(core::Object?) → core::int?} as{Unchecked} core::int in true)))
+             ^"){(core::Object?) → core::int?} in #t2 == null ?{core::int} #t2 as{Unchecked} core::int : #t2{core::int} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
 }
diff --git a/pkg/front_end/testcases/patterns/prefixed_extractor_pattern_with_type_args_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/prefixed_extractor_pattern_with_type_args_inside_cast.dart.weak.transformed.expect
index 878a12402be..36211bcd87a 100644
--- a/pkg/front_end/testcases/patterns/prefixed_extractor_pattern_with_type_args_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/prefixed_extractor_pattern_with_type_args_inside_cast.dart.weak.transformed.expect
@@ -10,7 +10,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in (#0#0 as{Unchecked} core::Object) is asy::Future<core::int>) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object}) is asy::Future<core::int>) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/record_pattern_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/record_pattern_inside_cast.dart.weak.transformed.expect
index 21aeba3115b..a041290ac19 100644
--- a/pkg/front_end/testcases/patterns/record_pattern_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/record_pattern_inside_cast.dart.weak.transformed.expect
@@ -7,7 +7,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in (#0#0 as{Unchecked} core::Object) is (core::Object?, core::Object?) && #C1 =={core::num::==}{(core::Object) → core::bool} ((#0#0 as{Unchecked} core::Object) as{Unchecked} (core::Object?, core::Object?)).$1{core::Object?} && #C2 =={core::num::==}{(core::Object) → core::bool} ((#0#0 as{Unchecked} core::Object) as{Unchecked} (core::Object?, core::Object?)).$2{core::Object?}) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object}) is (core::Object?, core::Object?) && #C1 =={core::num::==}{(core::Object) → core::bool} ((let dynamic #t4 = #0#0 in #t4 == null ?{core::Object} #t4 as core::Object : #t4{core::Object}) as{Unchecked} (core::Object?, core::Object?)).$1{core::Object?} && #C2 =={core::num::==}{(core::Object) → core::bool} ((let dynamic #t5 = #0#0 in #t5 == null ?{core::Object} #t5 as core::Object : #t5{core::Object}) as{Unchecked} (core::Object?, core::Object?)).$2{core::Object?}) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/string_literal_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/string_literal_inside_cast.dart.weak.transformed.expect
index f2d1a8f666b..825bb89e5e9 100644
--- a/pkg/front_end/testcases/patterns/string_literal_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/string_literal_inside_cast.dart.weak.transformed.expect
@@ -7,7 +7,7 @@ static method test(dynamic x) → dynamic {
   {
     final synthesized dynamic #0#0 = x;
     {
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in #C1 =={core::String::==}{(core::Object) → core::bool} #0#0 as{Unchecked} core::Object) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in #C1 =={core::String::==}{(core::Object) → core::bool} (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object})) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/typed_final_variable_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/typed_final_variable_inside_cast.dart.weak.transformed.expect
index 03577d6b0db..8e2261debfd 100644
--- a/pkg/front_end/testcases/patterns/typed_final_variable_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/typed_final_variable_inside_cast.dart.weak.transformed.expect
@@ -8,7 +8,7 @@ static method test(dynamic x) → dynamic {
     final synthesized dynamic #0#0 = x;
     {
       final hoisted core::int y;
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in (#0#0 as{Unchecked} core::Object) is core::int && (let final core::int #t2 = y = (#0#0 as{Unchecked} core::Object) as{Unchecked} core::int in true)) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object}) is core::int && (let final core::int #t4 = y = (let dynamic #t5 = #0#0 in #t5 == null ?{core::Object} #t5 as core::Object : #t5{core::Object}) as{Unchecked} core::int in true)) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/typed_variable_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/typed_variable_inside_cast.dart.weak.transformed.expect
index 031a582aa17..9196ecdb2a5 100644
--- a/pkg/front_end/testcases/patterns/typed_variable_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/typed_variable_inside_cast.dart.weak.transformed.expect
@@ -8,7 +8,7 @@ static method test(dynamic x) → dynamic {
     final synthesized dynamic #0#0 = x;
     {
       hoisted core::int y;
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in (#0#0 as{Unchecked} core::Object) is core::int && (let final core::int #t2 = y = (#0#0 as{Unchecked} core::Object) as{Unchecked} core::int in true)) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in (let dynamic #t3 = #0#0 in #t3 == null ?{core::Object} #t3 as core::Object : #t3{core::Object}) is core::int && (let final core::int #t4 = y = (let dynamic #t5 = #0#0 in #t5 == null ?{core::Object} #t5 as core::Object : #t5{core::Object}) as{Unchecked} core::int in true)) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/var_variable_inside_cast.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/var_variable_inside_cast.dart.weak.transformed.expect
index d0f207f8d51..429fd1b89a0 100644
--- a/pkg/front_end/testcases/patterns/var_variable_inside_cast.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/var_variable_inside_cast.dart.weak.transformed.expect
@@ -8,7 +8,7 @@ static method test(dynamic x) → dynamic {
     final synthesized dynamic #0#0 = x;
     {
       hoisted core::Object y;
-      if(let final core::Object #t1 = #0#0 as{Unchecked} core::Object in let final core::Object #t2 = y = #0#0 as{Unchecked} core::Object in true) {
+      if(let final core::Object #t1 = let dynamic #t2 = #0#0 in #t2 == null ?{core::Object} #t2 as core::Object : #t2{core::Object} in let final core::Object #t3 = y = let dynamic #t4 = #0#0 in #t4 == null ?{core::Object} #t4 as core::Object : #t4{core::Object} in true) {
         {
           break #L1;
         }
diff --git a/pkg/front_end/testcases/patterns/variable_names.dart.weak.transformed.expect b/pkg/front_end/testcases/patterns/variable_names.dart.weak.transformed.expect
index 180aea28cce..3638314dd2d 100644
--- a/pkg/front_end/testcases/patterns/variable_names.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/patterns/variable_names.dart.weak.transformed.expect
@@ -43,9 +43,9 @@ static method test(dynamic x, dynamic y, dynamic z) → dynamic {
       hoisted core::double boz;
       hoisted core::int foobar;
       if(#0#0 is self::A && (let final core::int? #t1 = (#0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t2 = #0#2#isSet = true in #0#2 = #0#0{self::A}.{self::A::foo}{core::int?})! in let final core::int? #t3 = foo = (#0#2#isSet ?{core::int?} #0#2{core::int?} : let final core::bool #t4 = #0#2#isSet = true in #0#2 = #0#0{self::A}.{self::A::foo}{core::int?})! in true) && (let final core::int #t5 = bar = #0#0{self::A}.{self::A::bar}{core::int} in true) && !((#0#5#isSet ?{core::int?} #0#5{core::int?} : let final core::bool #t6 = #0#5#isSet = true in #0#5 = #0#0{self::A}.{self::A::baz}{core::int?}) == null)) {
-        baz = (#0#5#isSet ?{core::int?} #0#5{core::int?} : let final core::bool #t7 = #0#5#isSet = true in #0#5 = #0#0{self::A}.{self::A::baz}{core::int?}) as{Unchecked} core::int;
-        (#0#7#isSet ?{core::num} #0#7{core::num} : let final core::bool #t8 = #0#7#isSet = true in #0#7 = #0#0{self::A}.{self::A::boz}{core::num}) as core::double;
-        boz = (#0#7#isSet ?{core::num} #0#7{core::num} : let final core::bool #t9 = #0#7#isSet = true in #0#7 = #0#0{self::A}.{self::A::boz}{core::num}) as core::double;
+        baz = let core::int? #t7 = #0#5#isSet ?{core::int?} #0#5{core::int?} : let final core::bool #t8 = #0#5#isSet = true in #0#5 = #0#0{self::A}.{self::A::baz}{core::int?} in #t7 == null ?{core::int} #t7 as{Unchecked} core::int : #t7{core::int};
+        (#0#7#isSet ?{core::num} #0#7{core::num} : let final core::bool #t9 = #0#7#isSet = true in #0#7 = #0#0{self::A}.{self::A::boz}{core::num}) as core::double;
+        boz = (#0#7#isSet ?{core::num} #0#7{core::num} : let final core::bool #t10 = #0#7#isSet = true in #0#7 = #0#0{self::A}.{self::A::boz}{core::num}) as core::double;
         foobar = #0#0{self::A}.{self::A::foobar}{core::int};
         {
           return 0;
@@ -65,10 +65,10 @@ static method test(dynamic x, dynamic y, dynamic z) → dynamic {
           hoisted dynamic baz;
           hoisted core::double boz;
           hoisted dynamic foobar;
-          if(#1#0 is (core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?}) && (let final core::Object? #t10 = (#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t11 = #1#2#isSet = true in #1#2 = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.foo{core::Object?})! in let final core::Object? #t12 = foo = (#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t13 = #1#2#isSet = true in #1#2 = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.foo{core::Object?})! in true) && (let final core::Object? #t14 = bar = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.bar{core::Object?} in true) && !((#1#5#isSet ?{core::Object?} #1#5{core::Object?} : let final core::bool #t15 = #1#5#isSet = true in #1#5 = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.baz{core::Object?}) == null)) {
-            baz = #1#5#isSet ?{core::Object?} #1#5{core::Object?} : let final core::bool #t16 = #1#5#isSet = true in #1#5 = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.baz{core::Object?};
-            (#1#7#isSet ?{core::Object?} #1#7{core::Object?} : let final core::bool #t17 = #1#7#isSet = true in #1#7 = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.$1{core::Object?}) as core::double;
-            boz = (#1#7#isSet ?{core::Object?} #1#7{core::Object?} : let final core::bool #t18 = #1#7#isSet = true in #1#7 = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.$1{core::Object?}) as core::double;
+          if(#1#0 is (core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?}) && (let final core::Object? #t11 = (#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t12 = #1#2#isSet = true in #1#2 = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.foo{core::Object?})! in let final core::Object? #t13 = foo = (#1#2#isSet ?{core::Object?} #1#2{core::Object?} : let final core::bool #t14 = #1#2#isSet = true in #1#2 = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.foo{core::Object?})! in true) && (let final core::Object? #t15 = bar = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.bar{core::Object?} in true) && !((#1#5#isSet ?{core::Object?} #1#5{core::Object?} : let final core::bool #t16 = #1#5#isSet = true in #1#5 = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.baz{core::Object?}) == null)) {
+            baz = #1#5#isSet ?{core::Object?} #1#5{core::Object?} : let final core::bool #t17 = #1#5#isSet = true in #1#5 = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.baz{core::Object?};
+            (#1#7#isSet ?{core::Object?} #1#7{core::Object?} : let final core::bool #t18 = #1#7#isSet = true in #1#7 = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.$1{core::Object?}) as core::double;
+            boz = (#1#7#isSet ?{core::Object?} #1#7{core::Object?} : let final core::bool #t19 = #1#7#isSet = true in #1#7 = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.$1{core::Object?}) as core::double;
             foobar = #1#0{(core::Object?, {bar: core::Object?, baz: core::Object?, foo: core::Object?, foobar: core::Object?})}.foobar{core::Object?};
             {
               return 1;
@@ -94,12 +94,12 @@ static method test(dynamic x, dynamic y, dynamic z) → dynamic {
   }
   {
     final synthesized dynamic #4#0 = y as{TypeError,ForDynamic} self::A;
-    if(!(#4#0 is self::A && (let final core::bool #t19 = qux = #4#0{self::A}.{self::A::qux}{core::bool} in true) && (let final core::String #t20 = quux = #4#0{self::A}.{self::A::quux}{core::String} in true)))
+    if(!(#4#0 is self::A && (let final core::bool #t20 = qux = #4#0{self::A}.{self::A::qux}{core::bool} in true) && (let final core::String #t21 = quux = #4#0{self::A}.{self::A::quux}{core::String} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
   {
     final synthesized dynamic #5#0 = z as{TypeError,ForDynamic} (dynamic, {quux: dynamic});
-    if(!(#5#0 is (core::Object?, {quux: core::Object?}) && (let final core::Object? #t21 = qux = #5#0{(core::Object?, {quux: core::Object?})}.$1{core::Object?} in true) && (let final core::Object? #t22 = quux = #5#0{(core::Object?, {quux: core::Object?})}.quux{core::Object?} in true)))
+    if(!(#5#0 is (core::Object?, {quux: core::Object?}) && (let final core::Object? #t22 = qux = #5#0{(core::Object?, {quux: core::Object?})}.$1{core::Object?} in true) && (let final core::Object? #t23 = quux = #5#0{(core::Object?, {quux: core::Object?})}.quux{core::Object?} in true)))
       throw{for-error-handling} new core::StateError::•("Pattern matching error");
   }
 }
diff --git a/pkg/frontend_server/lib/compute_kernel.dart b/pkg/frontend_server/lib/compute_kernel.dart
index e056542e163..07849b3d51b 100644
--- a/pkg/frontend_server/lib/compute_kernel.dart
+++ b/pkg/frontend_server/lib/compute_kernel.dart
@@ -22,8 +22,7 @@ import 'package:front_end/src/api_prototype/file_system.dart';
 import 'package:front_end/src/api_prototype/incremental_kernel_generator.dart';
 import 'package:front_end/src/api_unstable/bazel_worker.dart' as fe;
 import 'package:front_end/src/fasta/uri_translator.dart';
-import 'package:kernel/ast.dart'
-    show Component, Library, NonNullableByDefaultCompiledMode;
+import 'package:kernel/ast.dart' show Component, Library;
 import 'package:kernel/target/targets.dart';
 import 'package:vm/kernel_front_end.dart';
 import 'package:vm/modular/target/flutter.dart';
@@ -398,13 +397,7 @@ Future<ComputeKernelResult> computeKernel(List<String> args,
 
     nativeAssetsLibrary =
         await NativeAssetsSynthesizer.synthesizeLibraryFromYamlFile(
-      nativeAssetsUri,
-      new ErrorDetector(),
-      nonNullableByDefaultCompiledMode:
-          state.options.nnbdMode == fe.NnbdMode.Strong
-              ? NonNullableByDefaultCompiledMode.Strong
-              : NonNullableByDefaultCompiledMode.Weak,
-    );
+            nativeAssetsUri, new ErrorDetector());
   }
 
   if (usingIncrementalCompiler) {
diff --git a/pkg/frontend_server/lib/frontend_server.dart b/pkg/frontend_server/lib/frontend_server.dart
index 0fa5f98a9e2..92d6a2477ef 100644
--- a/pkg/frontend_server/lib/frontend_server.dart
+++ b/pkg/frontend_server/lib/frontend_server.dart
@@ -529,7 +529,6 @@ class FrontendCompiler implements CompilerInterface {
       ..explicitExperimentalFlags = parseExperimentalFlags(
           parseExperimentalArguments(options['enable-experiment']),
           onError: (msg) => errors.add(msg))
-      ..nnbdMode = soundNullSafety ? NnbdMode.Strong : NnbdMode.Weak
       ..onDiagnostic = _onDiagnostic
       ..verbosity = Verbosity.parseArgument(options['verbosity'],
           onError: (msg) => errors.add(msg));
@@ -606,7 +605,6 @@ class FrontendCompiler implements CompilerInterface {
     compilerOptions.target = createFrontEndTarget(
       options['target'],
       trackWidgetCreation: options['track-widget-creation'],
-      soundNullSafety: compilerOptions.nnbdMode == NnbdMode.Strong,
       supportMirrors: options['support-mirrors'] ??
           !(options['aot'] || options['minimal-kernel']),
     );
@@ -828,7 +826,6 @@ class FrontendCompiler implements CompilerInterface {
     PackageConfig packageConfig = await loadPackageConfigUri(
         _compilerOptions.packagesFileUri ??
             new File('.dart_tool/package_config.json').absolute.uri);
-    bool soundNullSafety = _compilerOptions.nnbdMode == NnbdMode.Strong;
     final Component component = results.component!;
 
     final IncrementalJavaScriptBundler bundler =
@@ -839,7 +836,6 @@ class FrontendCompiler implements CompilerInterface {
       useDebuggerModuleNames: useDebuggerModuleNames,
       emitDebugMetadata: emitDebugMetadata,
       moduleFormat: moduleFormat,
-      soundNullSafety: soundNullSafety,
       canaryFeatures: canaryFeatures,
     );
     if (fullComponent) {
diff --git a/pkg/frontend_server/lib/src/javascript_bundle.dart b/pkg/frontend_server/lib/src/javascript_bundle.dart
index 23ed2c83992..f72be19010a 100644
--- a/pkg/frontend_server/lib/src/javascript_bundle.dart
+++ b/pkg/frontend_server/lib/src/javascript_bundle.dart
@@ -37,7 +37,6 @@ class IncrementalJavaScriptBundler {
     this.useDebuggerModuleNames = false,
     this.emitDebugMetadata = false,
     this.emitDebugSymbols = false,
-    this.soundNullSafety = false,
     this.canaryFeatures = false,
     String? moduleFormat,
   }) : _moduleFormat = parseModuleFormat(moduleFormat ?? 'amd');
@@ -46,7 +45,6 @@ class IncrementalJavaScriptBundler {
   final bool emitDebugMetadata;
   final bool emitDebugSymbols;
   final ModuleFormat _moduleFormat;
-  final bool soundNullSafety;
   final bool canaryFeatures;
   final FileSystem? _fileSystem;
   final Set<Library> _loadedLibraries;
@@ -212,7 +210,7 @@ class IncrementalJavaScriptBundler {
           emitDebugMetadata: emitDebugMetadata,
           emitDebugSymbols: emitDebugSymbols,
           moduleName: moduleName,
-          soundNullSafety: soundNullSafety,
+          soundNullSafety: true,
           canaryFeatures: canaryFeatures,
         ),
         _importToSummary,
diff --git a/pkg/frontend_server/test/frontend_server_flutter.dart b/pkg/frontend_server/test/frontend_server_flutter.dart
index ed20ef2dbee..a6500d06381 100644
--- a/pkg/frontend_server/test/frontend_server_flutter.dart
+++ b/pkg/frontend_server/test/frontend_server_flutter.dart
@@ -16,10 +16,6 @@ import 'dart:io'
         exitCode;
 import 'dart:typed_data' show BytesBuilder, Uint8List;
 
-import 'package:front_end/src/api_prototype/language_version.dart'
-    show uriUsesLegacyLanguageVersion;
-import 'package:front_end/src/api_unstable/vm.dart'
-    show CompilerOptions, NnbdMode, StandardFileSystem;
 import 'package:frontend_server/starter.dart';
 import 'package:kernel/ast.dart' show Component, Library;
 import 'package:kernel/binary/multi_binary_loader.dart' show MultiBinaryLoader;
@@ -41,20 +37,6 @@ Future<void> main(List<String> args) async {
   await compileTests(flutterDir, flutterPlatformDir, new StdoutLogger());
 }
 
-Future<NnbdMode> _getNNBDMode(Uri script, Uri packageConfigUri) async {
-  final CompilerOptions compilerOptions = new CompilerOptions()
-    ..sdkRoot = null
-    ..fileSystem = StandardFileSystem.instance
-    ..packagesFileUri = packageConfigUri
-    ..sdkSummary = null
-    ..nnbdMode = NnbdMode.Weak;
-
-  if (await uriUsesLegacyLanguageVersion(script, compilerOptions)) {
-    return NnbdMode.Weak;
-  }
-  return NnbdMode.Strong;
-}
-
 Future compileTests(
     String? flutterDir, String? flutterPlatformDir, Logger logger,
     {String? filter, int shards = 1, int shard = 0}) async {
@@ -134,26 +116,9 @@ Future compileTests(
       return true;
     }));
 
-    // Split into NNBD Strong and Weak so only the ones that match are
-    // compiled together. If mixing-and-matching the first file (which could
-    // be either) will setup the compiler which can lead to compilation errors
-    // for another file, for instance if the first one is strong but a
-    // subsequent one tries to opt out (i.e. is weak) an error is issued that
-    // that's not possible.
-    List<File> weak = [];
-    List<File> strong = [];
-    for (File file in testFiles) {
-      if (await _getNNBDMode(file.uri, packageConfig.uri) == NnbdMode.Weak) {
-        weak.add(file);
-      } else {
-        strong.add(file);
-      }
-    }
-    for (List<File> files in [weak, strong]) {
-      if (files.isEmpty) continue;
-      queue.add(new _QueueEntry(files, packageConfig, testDir));
-      totalFiles += files.length;
-    }
+    if (testFiles.isEmpty) continue;
+    queue.add(new _QueueEntry(testFiles, packageConfig, testDir));
+    totalFiles += testFiles.length;
   }
 
   // Process queue, taking shards into account.
diff --git a/pkg/vm/bin/kernel_service.dart b/pkg/vm/bin/kernel_service.dart
index e09bcfc8dac..6ec752bfdae 100644
--- a/pkg/vm/bin/kernel_service.dart
+++ b/pkg/vm/bin/kernel_service.dart
@@ -34,12 +34,13 @@ import 'package:front_end/src/api_prototype/front_end.dart' as fe
     show CompilerResult;
 import 'package:front_end/src/api_prototype/memory_file_system.dart';
 import 'package:front_end/src/api_unstable/vm.dart';
+import 'package:kernel/ast.dart'
+    show Component, Library, NonNullableByDefaultCompiledMode, Procedure;
 import 'package:kernel/binary/ast_from_binary.dart'
     show BinaryBuilderWithMetadata;
 import 'package:kernel/binary/ast_to_binary.dart';
 import 'package:kernel/class_hierarchy.dart' show ClassHierarchy;
 import 'package:kernel/core_types.dart' show CoreTypes;
-import 'package:kernel/kernel.dart' show Component, Library, Procedure;
 import 'package:kernel/target/targets.dart' show Target, TargetFlags;
 import 'package:vm/http_filesystem.dart';
 import 'package:vm/incremental_compiler.dart';
@@ -907,7 +908,7 @@ Future _processLoadRequest(request) async {
       if (nativeAssetsLibrary != null) {
         nativeAssetsComponent = Component(
           libraries: [nativeAssetsLibrary],
-          mode: nativeAssetsLibrary.nonNullableByDefaultCompiledMode,
+          mode: NonNullableByDefaultCompiledMode.Strong,
         );
       }
     }
diff --git a/pkg/vm/bin/protobuf_aware_treeshaker.dart b/pkg/vm/bin/protobuf_aware_treeshaker.dart
index 220e2d65755..0163bf1d19e 100644
--- a/pkg/vm/bin/protobuf_aware_treeshaker.dart
+++ b/pkg/vm/bin/protobuf_aware_treeshaker.dart
@@ -105,14 +105,14 @@ Future main(List<String> args) async {
     bytes = concatenate(File(platformFile).readAsBytesSync(), bytes);
   }
   final component = loadComponentFromBytes(bytes);
+  if (component.mode != NonNullableByDefaultCompiledMode.Strong) {
+    print('Input kernel file should be compiled with sound null safety.');
+    exit(-1);
+  }
 
   installAdditionalTargets();
 
-  final target = getTarget(
-      argResults['target'],
-      TargetFlags(
-          soundNullSafety:
-              component.mode == NonNullableByDefaultCompiledMode.Strong))!;
+  final target = getTarget(argResults['target'], TargetFlags())!;
 
   // The [component] is treeshaken and has TFA annotations. Write output.
   if (argResults['aot']) {
diff --git a/pkg/vm/lib/kernel_front_end.dart b/pkg/vm/lib/kernel_front_end.dart
index c5fc2ce2767..460876fb6d7 100644
--- a/pkg/vm/lib/kernel_front_end.dart
+++ b/pkg/vm/lib/kernel_front_end.dart
@@ -24,7 +24,6 @@ import 'package:front_end/src/api_unstable/vm.dart'
         DiagnosticMessageHandler,
         FileSystem,
         FileSystemEntity,
-        NnbdMode,
         ProcessedOptions,
         Severity,
         StandardFileSystem,
@@ -219,7 +218,6 @@ Future<int> runCompiler(ArgResults options, String usage) async {
   final bool linkPlatform = options['link-platform'];
   final bool embedSources = options['embed-sources'];
   final bool enableAsserts = options['enable-asserts'];
-  final bool soundNullSafety = options['sound-null-safety'];
   final bool useProtobufTreeShakerV2 = options['protobuf-tree-shaker-v2'];
   final String? manifestFilename = options['manifest'];
   final String? dataDir = options['component-name'] ?? options['data-dir'];
@@ -235,6 +233,7 @@ Future<int> runCompiler(ArgResults options, String usage) async {
     return badUsageExitCode;
   }
 
+  final bool soundNullSafety = options['sound-null-safety'];
   if (!soundNullSafety) {
     print('Error: --no-sound-null-safety is not supported.');
     return badUsageExitCode;
@@ -304,7 +303,6 @@ Future<int> runCompiler(ArgResults options, String usage) async {
     ..explicitExperimentalFlags = parseExperimentalFlags(
         parseExperimentalArguments(experimentalFlags),
         onError: print)
-    ..nnbdMode = soundNullSafety ? NnbdMode.Strong : NnbdMode.Weak
     ..onDiagnostic = (DiagnosticMessage m) {
       errorDetector(m);
     }
@@ -315,7 +313,6 @@ Future<int> runCompiler(ArgResults options, String usage) async {
 
   compilerOptions.target = createFrontEndTarget(targetName,
       trackWidgetCreation: options['track-widget-creation'],
-      soundNullSafety: compilerOptions.nnbdMode == NnbdMode.Strong,
       supportMirrors: supportMirrors ?? !(aot || minimalKernel));
   if (compilerOptions.target == null) {
     print('Failed to create front-end target $targetName.');
@@ -369,7 +366,7 @@ Future<int> runCompiler(ArgResults options, String usage) async {
     final BinaryPrinter printer = new BinaryPrinter(sink);
     printer.writeComponentFile(Component(
       libraries: [nativeAssetsLibrary],
-      mode: nativeAssetsLibrary.nonNullableByDefaultCompiledMode,
+      mode: NonNullableByDefaultCompiledMode.Strong,
     ));
   }
   await sink.close();
@@ -456,12 +453,7 @@ Future<KernelCompilationResults> compileToKernel(
 
   final nativeAssetsLibrary =
       await NativeAssetsSynthesizer.synthesizeLibraryFromYamlFile(
-    nativeAssets,
-    errorDetector,
-    nonNullableByDefaultCompiledMode: options.nnbdMode == NnbdMode.Strong
-        ? NonNullableByDefaultCompiledMode.Strong
-        : NonNullableByDefaultCompiledMode.Weak,
-  );
+          nativeAssets, errorDetector);
   if (source == null) {
     return KernelCompilationResults.named(
       nativeAssetsLibrary: nativeAssetsLibrary,
@@ -500,7 +492,6 @@ Future<KernelCompilationResults> compileToKernel(
     await runGlobalTransformations(target, component, useGlobalTypeFlowAnalysis,
         enableAsserts, useProtobufTreeShakerV2, errorDetector,
         environmentDefines: options.environmentDefines,
-        nnbdMode: options.nnbdMode,
         targetOS: targetOS,
         minimalKernel: minimalKernel,
         treeShakeWriteOnlyFields: treeShakeWriteOnlyFields,
@@ -567,7 +558,6 @@ Future runGlobalTransformations(
     {bool minimalKernel = false,
     bool treeShakeWriteOnlyFields = false,
     bool useRapidTypeAnalysis = true,
-    NnbdMode nnbdMode = NnbdMode.Weak,
     Map<String, String>? environmentDefines,
     List<String>? keepClassNamesImplementing,
     String? targetOS,
@@ -589,7 +579,7 @@ Future runGlobalTransformations(
   // type flow analysis so TFA won't take unreachable code into account.
   final os = targetOS != null ? TargetOS.fromString(targetOS)! : null;
   final evaluator = vm_constant_evaluator.VMConstantEvaluator.create(
-      target, component, os, nnbdMode,
+      target, component, os,
       enableAsserts: enableAsserts,
       environmentDefines: environmentDefines,
       coreTypes: coreTypes);
@@ -721,16 +711,12 @@ bool parseCommandLineDefines(
 
 /// Create front-end target with given name.
 Target? createFrontEndTarget(String targetName,
-    {bool trackWidgetCreation = false,
-    bool soundNullSafety = true,
-    bool supportMirrors = true}) {
+    {bool trackWidgetCreation = false, bool supportMirrors = true}) {
   // Make sure VM-specific targets are available.
   installAdditionalTargets();
 
   final TargetFlags targetFlags = new TargetFlags(
-      trackWidgetCreation: trackWidgetCreation,
-      soundNullSafety: soundNullSafety,
-      supportMirrors: supportMirrors);
+      trackWidgetCreation: trackWidgetCreation, supportMirrors: supportMirrors);
   return getTarget(targetName, targetFlags);
 }
 
diff --git a/pkg/vm/lib/modular/target/vm.dart b/pkg/vm/lib/modular/target/vm.dart
index 80c39d82b0c..e2addb91222 100644
--- a/pkg/vm/lib/modular/target/vm.dart
+++ b/pkg/vm/lib/modular/target/vm.dart
@@ -196,7 +196,7 @@ class VmTarget extends Target {
 
     bool productMode = environmentDefines!["dart.vm.product"] == "true";
     lowering.transformLibraries(libraries, coreTypes, hierarchy,
-        soundNullSafety: flags.soundNullSafety, productMode: productMode);
+        productMode: productMode);
     logger?.call("Lowering transformations performed");
 
     callSiteAnnotator.transformLibraries(
@@ -213,7 +213,7 @@ class VmTarget extends Target {
       {void Function(String msg)? logger}) {
     bool productMode = environmentDefines!["dart.vm.product"] == "true";
     lowering.transformProcedure(procedure, coreTypes, hierarchy,
-        soundNullSafety: flags.soundNullSafety, productMode: productMode);
+        productMode: productMode);
     logger?.call("Lowering transformations performed");
   }
 
diff --git a/pkg/vm/lib/modular/transformations/lowering.dart b/pkg/vm/lib/modular/transformations/lowering.dart
index 13b28fdbff9..a9c1328ceba 100644
--- a/pkg/vm/lib/modular/transformations/lowering.dart
+++ b/pkg/vm/lib/modular/transformations/lowering.dart
@@ -22,23 +22,20 @@ import 'type_casts_optimizer.dart' as typeCastsOptimizer
 /// after transforming children nodes.
 void transformLibraries(
     List<Library> libraries, CoreTypes coreTypes, ClassHierarchy hierarchy,
-    {required bool soundNullSafety, required bool productMode}) {
-  final transformer = _Lowering(coreTypes, hierarchy,
-      soundNullSafety: soundNullSafety, productMode: productMode);
+    {required bool productMode}) {
+  final transformer = _Lowering(coreTypes, hierarchy, productMode: productMode);
   libraries.forEach(transformer.visitLibrary);
 }
 
 void transformProcedure(
     Procedure procedure, CoreTypes coreTypes, ClassHierarchy hierarchy,
-    {required bool soundNullSafety, required bool productMode}) {
-  final transformer = _Lowering(coreTypes, hierarchy,
-      soundNullSafety: soundNullSafety, productMode: productMode);
+    {required bool productMode}) {
+  final transformer = _Lowering(coreTypes, hierarchy, productMode: productMode);
   procedure.accept(transformer);
 }
 
 class _Lowering extends Transformer {
   final TypeEnvironment env;
-  final bool soundNullSafety;
   final LateVarInitTransformer lateVarInitTransformer;
   final FactorySpecializer factorySpecializer;
   final ListLiteralsLowering listLiteralsLowering;
@@ -49,7 +46,7 @@ class _Lowering extends Transformer {
   StaticTypeContext? _cachedStaticTypeContext;
 
   _Lowering(CoreTypes coreTypes, ClassHierarchy hierarchy,
-      {required this.soundNullSafety, required bool productMode})
+      {required bool productMode})
       : env = TypeEnvironment(coreTypes, hierarchy),
         lateVarInitTransformer = LateVarInitTransformer(),
         factorySpecializer = FactorySpecializer(coreTypes),
@@ -97,8 +94,7 @@ class _Lowering extends Transformer {
   @override
   visitAsExpression(AsExpression node) {
     node.transformChildren(this);
-    return typeCastsOptimizer.transformAsExpression(
-        node, _staticTypeContext, soundNullSafety);
+    return typeCastsOptimizer.transformAsExpression(node, _staticTypeContext);
   }
 
   @override
diff --git a/pkg/vm/lib/modular/transformations/type_casts_optimizer.dart b/pkg/vm/lib/modular/transformations/type_casts_optimizer.dart
index 9940759fc2f..d0fc05a61c3 100644
--- a/pkg/vm/lib/modular/transformations/type_casts_optimizer.dart
+++ b/pkg/vm/lib/modular/transformations/type_casts_optimizer.dart
@@ -10,25 +10,25 @@ import 'package:kernel/type_environment.dart'
 // Removes redundant type casts and reduces casts to null checks.
 //
 // Handles the following patterns:
-// If S <: T (this includes S <: T? in weak mode)
+// If S <: T
 //
 //    S x; x as T => x
 //
-// If S <: T? in strong mode
+// If S <: T?
 //
 //    S x; x as T => (x == null) ? x as T : x
 //
-TreeNode transformAsExpression(AsExpression node,
-    StaticTypeContext staticTypeContext, bool soundNullSafety) {
+TreeNode transformAsExpression(
+    AsExpression node, StaticTypeContext staticTypeContext) {
   final DartType operandType = node.operand.getStaticType(staticTypeContext);
   final env = staticTypeContext.typeEnvironment;
 
-  if (isRedundantTypeCast(node, operandType, env, soundNullSafety)) {
+  if (isRedundantTypeCast(node, operandType, env)) {
     node.isUnchecked = true;
     return node;
   }
 
-  if (canBeReducedToNullCheckAndCast(node, operandType, env, soundNullSafety)) {
+  if (canBeReducedToNullCheckAndCast(node, operandType, env)) {
     // Transform 'x as T' to 'Let tmp = x in (tmp == null) ? tmp as T : tmp'.
     final tmp = VariableDeclaration(null,
         initializer: node.operand, type: operandType, isSynthesized: true);
@@ -50,32 +50,28 @@ TreeNode transformAsExpression(AsExpression node,
 // Returns true if type cast [node] which has operand of the given
 // [operandStaticType] is redundant and can be removed (replaced with its
 // operand).
-bool isRedundantTypeCast(AsExpression node, DartType operandStaticType,
-    TypeEnvironment env, bool soundNullSafety) {
+bool isRedundantTypeCast(
+    AsExpression node, DartType operandStaticType, TypeEnvironment env) {
   if (!_canBeTransformed(node, env.coreTypes)) {
     return false;
   }
 
   return env.isSubtypeOf(
-      operandStaticType,
-      node.type,
-      soundNullSafety
-          ? SubtypeCheckMode.withNullabilities
-          : SubtypeCheckMode.ignoringNullabilities);
+      operandStaticType, node.type, SubtypeCheckMode.withNullabilities);
 }
 
 // Returns true if type cast [node] which has operand of the given
 // [operandStaticType] can be reduced to the null-check-and-cast pattern
 // 'Let tmp = [node.operand] in (tmp == null) ? tmp as T : tmp'.
-bool canBeReducedToNullCheckAndCast(AsExpression node,
-    DartType operandStaticType, TypeEnvironment env, bool soundNullSafety) {
+bool canBeReducedToNullCheckAndCast(
+    AsExpression node, DartType operandStaticType, TypeEnvironment env) {
   if (!_canBeTransformed(node, env.coreTypes)) {
     return false;
   }
 
   final DartType dst = node.type;
 
-  if (soundNullSafety && dst.nullability != Nullability.nullable) {
+  if (dst.nullability != Nullability.nullable) {
     final nullableDst = dst.withDeclaredNullability(Nullability.nullable);
     return env.isSubtypeOf(
         operandStaticType, nullableDst, SubtypeCheckMode.withNullabilities);
diff --git a/pkg/vm/lib/native_assets/synthesizer.dart b/pkg/vm/lib/native_assets/synthesizer.dart
index 7f36ae5a53d..4d8321a3dc9 100644
--- a/pkg/vm/lib/native_assets/synthesizer.dart
+++ b/pkg/vm/lib/native_assets/synthesizer.dart
@@ -50,7 +50,6 @@ class NativeAssetsSynthesizer {
   /// The VM consumes this component in runtime/vm/ffi/native_assets.cc.
   static Library synthesizeLibrary(
     Map nativeAssetsYaml, {
-    nonNullableByDefaultCompiledMode = NonNullableByDefaultCompiledMode.Strong,
     Class? pragmaClass,
   }) {
     // We don't need the format-version in the VM.
@@ -72,10 +71,7 @@ class NativeAssetsSynthesizer {
           pragmaOptions.fieldReference: nativeAssetsConstant,
         }))
       ],
-    )
-      ..nonNullableByDefaultCompiledMode = nonNullableByDefaultCompiledMode
-      ..isNonNullableByDefault = nonNullableByDefaultCompiledMode ==
-          NonNullableByDefaultCompiledMode.Strong;
+    );
   }
 
   /// Loads [nativeAssetsYamlString], validates the contents, and synthesizes
@@ -87,8 +83,6 @@ class NativeAssetsSynthesizer {
   static Future<Library?> synthesizeLibraryFromYamlString(
     String? nativeAssetsYamlString,
     ErrorDetector errorDetector, {
-    NonNullableByDefaultCompiledMode nonNullableByDefaultCompiledMode =
-        NonNullableByDefaultCompiledMode.Strong,
     Class? pragmaClass,
   }) async {
     if (nativeAssetsYamlString == null) {
@@ -102,7 +96,6 @@ class NativeAssetsSynthesizer {
     }
     return NativeAssetsSynthesizer.synthesizeLibrary(
       nativeAssetsYaml,
-      nonNullableByDefaultCompiledMode: nonNullableByDefaultCompiledMode,
       pragmaClass: pragmaClass,
     );
   }
@@ -116,8 +109,6 @@ class NativeAssetsSynthesizer {
   static Future<Library?> synthesizeLibraryFromYamlFile(
     Uri? nativeAssetsUri,
     ErrorDetector errorDetector, {
-    NonNullableByDefaultCompiledMode nonNullableByDefaultCompiledMode =
-        NonNullableByDefaultCompiledMode.Strong,
     Class? pragmaClass,
   }) async {
     if (nativeAssetsUri == null) {
@@ -138,7 +129,6 @@ class NativeAssetsSynthesizer {
     return synthesizeLibraryFromYamlString(
       nativeAssetsYamlString,
       errorDetector,
-      nonNullableByDefaultCompiledMode: nonNullableByDefaultCompiledMode,
       pragmaClass: pragmaClass,
     );
   }
diff --git a/pkg/vm/lib/testing/il_matchers.dart b/pkg/vm/lib/testing/il_matchers.dart
index 3b316df7400..5990b7c833c 100644
--- a/pkg/vm/lib/testing/il_matchers.dart
+++ b/pkg/vm/lib/testing/il_matchers.dart
@@ -28,8 +28,6 @@ class FlowGraph {
         codegenBlockOrder =
             codegenBlockOrder?.map((idx) => _blocks[idx as int]).toList();
 
-  bool get soundNullSafety => flags['nnbd'];
-
   PrettyPrinter get printer => PrettyPrinter(descriptors);
 
   List<dynamic> blocks({bool inCodegenBlockOrder = false}) {
diff --git a/pkg/vm/lib/transformations/type_flow/analysis.dart b/pkg/vm/lib/transformations/type_flow/analysis.dart
index 4012ac46a81..4d0d254422e 100644
--- a/pkg/vm/lib/transformations/type_flow/analysis.dart
+++ b/pkg/vm/lib/transformations/type_flow/analysis.dart
@@ -1358,7 +1358,7 @@ class _ClassHierarchyCache extends TypeHierarchy {
       getTFClass(coreTypes.deprecatedNullClass);
 
   _ClassHierarchyCache(this._typeFlowAnalysis, this.genericInterfacesInfo,
-      super.coreTypes, super.target, super.soundNullSafety)
+      super.coreTypes, super.target)
       : objectNoSuchMethod =
             coreTypes.index.getProcedure('dart:core', 'Object', 'noSuchMethod');
 
@@ -1753,8 +1753,8 @@ class TypeFlowAnalysis
       : annotationMatcher =
             matcher ?? new ConstantPragmaAnnotationParser(coreTypes, target) {
     nativeCodeOracle = new NativeCodeOracle(libraryIndex, annotationMatcher);
-    hierarchyCache = new _ClassHierarchyCache(this, _genericInterfacesInfo,
-        coreTypes, target, target.flags.soundNullSafety);
+    hierarchyCache = new _ClassHierarchyCache(
+        this, _genericInterfacesInfo, coreTypes, target);
     summaryCollector = new SummaryCollector(
         target,
         environment,
diff --git a/pkg/vm/lib/transformations/type_flow/signature_shaking.dart b/pkg/vm/lib/transformations/type_flow/signature_shaking.dart
index 6c99ffa5c2e..37977d77cc9 100644
--- a/pkg/vm/lib/transformations/type_flow/signature_shaking.dart
+++ b/pkg/vm/lib/transformations/type_flow/signature_shaking.dart
@@ -190,12 +190,7 @@ class _ParameterInfo {
     }
 
     // Covariant parameters have implicit type checks, which count as reads.
-    // When run in weak mode with null assertions enabled, parameters with
-    // non-nullable types have implicit null checks, which count as reads.
-    if ((param.isCovariantByDeclaration || param.isCovariantByClass) ||
-        (!shaker.typeFlowAnalysis.target.flags.soundNullSafety &&
-            param.type.nullability == Nullability.nonNullable &&
-            (type == null || type is NullableType))) {
+    if (param.isCovariantByDeclaration || param.isCovariantByClass) {
       isChecked = true;
     }
 
diff --git a/pkg/vm/lib/transformations/type_flow/transformer.dart b/pkg/vm/lib/transformations/type_flow/transformer.dart
index 5266ace7d53..8de98411e4d 100644
--- a/pkg/vm/lib/transformations/type_flow/transformer.dart
+++ b/pkg/vm/lib/transformations/type_flow/transformer.dart
@@ -1773,12 +1773,7 @@ class _TreeShakerPass1 extends RemovingTransformer {
       }
     }
     final right = transform(node.right);
-    // Without sound null safety arguments of logical expression
-    // are implicitly checked for null, so transform the node only
-    // if using sound null safety or it evaluates to a bool literal.
-    if (_isExtendedBoolLiteral(left) &&
-        (shaker.typeFlowAnalysis.target.flags.soundNullSafety ||
-            _isExtendedBoolLiteral(right))) {
+    if (_isExtendedBoolLiteral(left)) {
       return _evaluateArguments([left], right);
     }
     node.left = left..parent = node;
diff --git a/pkg/vm/lib/transformations/type_flow/types.dart b/pkg/vm/lib/transformations/type_flow/types.dart
index 0b986e1407c..77e90fdfbc3 100644
--- a/pkg/vm/lib/transformations/type_flow/types.dart
+++ b/pkg/vm/lib/transformations/type_flow/types.dart
@@ -193,9 +193,8 @@ abstract class GenericInterfacesInfo {
 abstract class TypesBuilder {
   final CoreTypes coreTypes;
   final Target target;
-  final bool soundNullSafety;
 
-  TypesBuilder(this.coreTypes, this.target, this.soundNullSafety);
+  TypesBuilder(this.coreTypes, this.target);
 
   /// Return [TFClass] corresponding to the given [classNode].
   TFClass getTFClass(Class classNode);
@@ -259,7 +258,7 @@ abstract class TypesBuilder {
     } else {
       throw 'Unexpected type ${type.runtimeType} $type';
     }
-    if (soundNullSafety && type.nullability == Nullability.nonNullable) {
+    if (type.nullability == Nullability.nonNullable) {
       canBeNull = false;
     }
     if (canBeNull) {
@@ -276,8 +275,7 @@ abstract class RuntimeTypeTranslator {
 /// Abstract interface to type hierarchy information used by types.
 abstract class TypeHierarchy extends TypesBuilder
     implements GenericInterfacesInfo {
-  TypeHierarchy(CoreTypes coreTypes, Target target, bool soundNullSafety)
-      : super(coreTypes, target, soundNullSafety);
+  TypeHierarchy(CoreTypes coreTypes, Target target) : super(coreTypes, target);
 
   /// Test if [sub] is a subtype of [sup].
   bool isSubtype(Class sub, Class sup) {
@@ -465,8 +463,7 @@ class NullableType extends Type {
       TypeHierarchy typeHierarchy, RuntimeType other, SubtypeTestKind kind) {
     switch (kind) {
       case SubtypeTestKind.Subtype:
-        if (typeHierarchy.soundNullSafety &&
-            other.nullability == Nullability.nonNullable) {
+        if (other.nullability == Nullability.nonNullable) {
           return false;
         }
         break;
@@ -1591,8 +1588,7 @@ class RuntimeType extends Type {
       throw 'RuntimeType could be only tested for subtyping.';
     }
     final rhs = runtimeType._type;
-    if (typeHierarchy.soundNullSafety &&
-        _type.nullability == Nullability.nullable &&
+    if (_type.nullability == Nullability.nullable &&
         rhs.nullability == Nullability.nonNullable) {
       return false;
     }
diff --git a/pkg/vm/lib/transformations/unreachable_code_elimination.dart b/pkg/vm/lib/transformations/unreachable_code_elimination.dart
index bf3d9c27a3c..1fe0706d87b 100644
--- a/pkg/vm/lib/transformations/unreachable_code_elimination.dart
+++ b/pkg/vm/lib/transformations/unreachable_code_elimination.dart
@@ -16,21 +16,18 @@ import 'vm_constant_evaluator.dart' show VMConstantEvaluator;
 /// applied to certain types of expressions (currently only StaticGet).
 Component transformComponent(Target target, Component component,
     VMConstantEvaluator evaluator, bool enableAsserts) {
-  SimpleUnreachableCodeElimination(evaluator,
-          enableAsserts: enableAsserts,
-          soundNullSafety: target.flags.soundNullSafety)
+  SimpleUnreachableCodeElimination(evaluator, enableAsserts: enableAsserts)
       .visitComponent(component, null);
   return component;
 }
 
 class SimpleUnreachableCodeElimination extends RemovingTransformer {
-  final bool soundNullSafety;
   final bool enableAsserts;
   final VMConstantEvaluator constantEvaluator;
   StaticTypeContext? _staticTypeContext;
 
   SimpleUnreachableCodeElimination(this.constantEvaluator,
-      {required this.enableAsserts, required this.soundNullSafety});
+      {required this.enableAsserts});
 
   Never _throwPlatformConstError(Member node, String message) {
     final uri = constantEvaluator.getFileUri(node);
@@ -154,18 +151,11 @@ class SimpleUnreachableCodeElimination extends RemovingTransformer {
     // Because of short-circuiting, these operators cannot be treated as
     // symmetric, so a non-constant left and a constant right is left as-is.
     if (value == null) return node;
-    // If the RHS is not a known constant and may evaluate to null, then
-    // we must keep the whole node if the LHS does not short circuit, as the
-    // operator performs a null check on the RHS value.
-    final evaluateRight =
-        soundNullSafety || _getBoolConstantValue(node.right) != null
-            ? node.right
-            : node;
     switch (node.operatorEnum) {
       case LogicalExpressionOperator.OR:
-        return value ? node.left : evaluateRight;
+        return value ? node.left : node.right;
       case LogicalExpressionOperator.AND:
-        return value ? evaluateRight : node.left;
+        return value ? node.right : node.left;
     }
   }
 
diff --git a/pkg/vm/lib/transformations/vm_constant_evaluator.dart b/pkg/vm/lib/transformations/vm_constant_evaluator.dart
index 6cfb775fc82..67d6b1c6b7e 100644
--- a/pkg/vm/lib/transformations/vm_constant_evaluator.dart
+++ b/pkg/vm/lib/transformations/vm_constant_evaluator.dart
@@ -9,7 +9,6 @@ import 'package:kernel/target/targets.dart'
     show ConstantsBackend, DartLibrarySupport, Target;
 import 'package:kernel/type_environment.dart';
 
-import 'package:front_end/src/base/nnbd_mode.dart';
 import 'package:front_end/src/fasta/kernel/constant_evaluator.dart'
     show ConstantEvaluator, ErrorReporter, EvaluationMode, SimpleErrorReporter;
 
@@ -44,8 +43,7 @@ class VMConstantEvaluator extends ConstantEvaluator {
       this._pragmaParser,
       {bool enableTripleShift = false,
       bool enableAsserts = true,
-      bool errorOnUnevaluatedConstant = false,
-      EvaluationMode evaluationMode = EvaluationMode.weak})
+      bool errorOnUnevaluatedConstant = false})
       : _platformClass = typeEnvironment.coreTypes.platformClass,
         super(dartLibrarySupport, backend, component, environmentDefines,
             typeEnvironment, errorReporter,
@@ -55,7 +53,7 @@ class VMConstantEvaluator extends ConstantEvaluator {
             enableConstFunctions: true,
             enableAsserts: enableAsserts,
             errorOnUnevaluatedConstant: errorOnUnevaluatedConstant,
-            evaluationMode: evaluationMode) {
+            evaluationMode: EvaluationMode.strong) {
     // Only add Platform fields if the Platform class is part of the component
     // being evaluated.
     if (_targetOS != null && _platformClass != null) {
@@ -66,7 +64,7 @@ class VMConstantEvaluator extends ConstantEvaluator {
   }
 
   static VMConstantEvaluator create(
-      Target target, Component component, TargetOS? targetOS, NnbdMode nnbdMode,
+      Target target, Component component, TargetOS? targetOS,
       {bool evaluateAnnotations = true,
       bool enableTripleShift = false,
       bool enableConstructorTearOff = false,
@@ -96,8 +94,7 @@ class VMConstantEvaluator extends ConstantEvaluator {
         ConstantPragmaAnnotationParser(coreTypes, target),
         enableTripleShift: enableTripleShift,
         enableAsserts: enableAsserts,
-        errorOnUnevaluatedConstant: errorOnUnevaluatedConstant,
-        evaluationMode: EvaluationMode.fromNnbdMode(nnbdMode));
+        errorOnUnevaluatedConstant: errorOnUnevaluatedConstant);
   }
 
   bool get _hasTargetOS => _targetOS != null;
diff --git a/pkg/vm/test/common_test_utils.dart b/pkg/vm/test/common_test_utils.dart
index b8402e5a0d7..fe55641eccf 100644
--- a/pkg/vm/test/common_test_utils.dart
+++ b/pkg/vm/test/common_test_utils.dart
@@ -13,7 +13,6 @@ import 'package:front_end/src/api_unstable/vm.dart'
         computePlatformBinariesLocation,
         kernelForModule,
         kernelForProgram,
-        NnbdMode,
         parseExperimentalArguments,
         parseExperimentalFlags;
 import 'package:kernel/ast.dart';
@@ -47,7 +46,6 @@ Future<Component> compileTestCaseToKernelProgram(Uri sourceUri,
       ..additionalDills = <Uri>[platformKernel]
       ..environmentDefines = environmentDefines
       ..packagesFileUri = packagesFileUri
-      ..nnbdMode = NnbdMode.Strong
       ..explicitExperimentalFlags =
           parseExperimentalFlags(parseExperimentalArguments(experimentalFlags),
               onError: (String message) {
diff --git a/pkg/vm/test/incremental_compiler_test.dart b/pkg/vm/test/incremental_compiler_test.dart
index 9771e531662..bf14a4bfbad 100644
--- a/pkg/vm/test/incremental_compiler_test.dart
+++ b/pkg/vm/test/incremental_compiler_test.dart
@@ -13,7 +13,6 @@ import 'package:front_end/src/api_unstable/vm.dart'
         DiagnosticMessage,
         ExperimentalFlag,
         IncrementalCompilerResult,
-        NnbdMode,
         computePlatformBinariesLocation;
 import 'package:json_rpc_2/json_rpc_2.dart' as json_rpc;
 import 'package:kernel/binary/ast_to_binary.dart';
@@ -37,7 +36,6 @@ main() {
   CompilerOptions getFreshOptions() {
     return new CompilerOptions()
       ..sdkRoot = sdkRoot
-      ..nnbdMode = NnbdMode.Strong
       ..target = new VmTarget(new TargetFlags())
       ..additionalDills = <Uri>[platformKernel]
       ..onDiagnostic = (DiagnosticMessage message) {
diff --git a/pkg/vm/test/modular_kernel_plus_aot_test.dart b/pkg/vm/test/modular_kernel_plus_aot_test.dart
index c9875a5ef81..e0d6434db99 100644
--- a/pkg/vm/test/modular_kernel_plus_aot_test.dart
+++ b/pkg/vm/test/modular_kernel_plus_aot_test.dart
@@ -28,8 +28,7 @@ main() async {
   final Uri packagesFile = sdkRootFile('.dart_tool/package_config.json');
   final Uri librariesFile = sdkRootFile('sdk/lib/libraries.json');
 
-  final vmTarget =
-      VmTarget(TargetFlags(supportMirrors: false, soundNullSafety: true));
+  final vmTarget = VmTarget(TargetFlags(supportMirrors: false));
 
   await withTempDirectory((Uri uri) async {
     final mixinFilename = uri.resolve('mixin.dart');
diff --git a/pkg/vm/test/transformations/mixin_deduplication_test.dart b/pkg/vm/test/transformations/mixin_deduplication_test.dart
index 52c46d5eda3..95e35faee57 100644
--- a/pkg/vm/test/transformations/mixin_deduplication_test.dart
+++ b/pkg/vm/test/transformations/mixin_deduplication_test.dart
@@ -16,7 +16,7 @@ import '../common_test_utils.dart';
 final String pkgVmDir = Platform.script.resolve('../..').toFilePath();
 
 runTestCase(Uri source) async {
-  final target = VmTarget(new TargetFlags(soundNullSafety: true));
+  final target = VmTarget(new TargetFlags());
   final component =
       await compileTestCaseToKernelProgram(source, target: target);
   transformComponent(component);
diff --git a/pkg/vm/test/transformations/type_flow/summary_collector_test.dart b/pkg/vm/test/transformations/type_flow/summary_collector_test.dart
index d9c7bd1ca23..e495b8e9a07 100644
--- a/pkg/vm/test/transformations/type_flow/summary_collector_test.dart
+++ b/pkg/vm/test/transformations/type_flow/summary_collector_test.dart
@@ -32,7 +32,7 @@ class FakeTypesBuilder extends TypesBuilder {
   int _classIdCounter = 0;
 
   FakeTypesBuilder(CoreTypes coreTypes, Target target)
-      : super(coreTypes, target, /*soundNullSafety=*/ true);
+      : super(coreTypes, target);
 
   @override
   TFClass getTFClass(Class c) =>
diff --git a/pkg/vm/test/transformations/type_flow/types_test.dart b/pkg/vm/test/transformations/type_flow/types_test.dart
index 55a16386a8b..36b990621cd 100644
--- a/pkg/vm/test/transformations/type_flow/types_test.dart
+++ b/pkg/vm/test/transformations/type_flow/types_test.dart
@@ -19,7 +19,7 @@ class TestTypeHierarchy extends TypeHierarchy {
 
   TestTypeHierarchy(
       CoreTypes coreTypes, Target target, this.classes, this.specializations)
-      : super(coreTypes, target, /*soundNullSafety=*/ true);
+      : super(coreTypes, target);
 
   @override
   Type specializeTypeCone(TFClass base, {bool allowWideCone = false}) {
diff --git a/pkg/vm/test/transformations/unreachable_code_elimination_test.dart b/pkg/vm/test/transformations/unreachable_code_elimination_test.dart
index 266ad9b3135..ffe63446587 100644
--- a/pkg/vm/test/transformations/unreachable_code_elimination_test.dart
+++ b/pkg/vm/test/transformations/unreachable_code_elimination_test.dart
@@ -4,7 +4,6 @@
 
 import 'dart:io';
 
-import 'package:front_end/src/base/nnbd_mode.dart';
 import 'package:kernel/target/targets.dart';
 import 'package:kernel/ast.dart';
 import 'package:kernel/kernel.dart';
@@ -23,19 +22,15 @@ runTestCase(Uri source) async {
   // Do not perform constant evaluation for a specific target operating system.
   final targetOS = null;
   final enableAsserts = false;
-  final soundNullSafety = true;
-  final nnbdMode = NnbdMode.Strong;
 
-  final target =
-      new VmTarget(new TargetFlags(soundNullSafety: soundNullSafety));
+  final target = new VmTarget(new TargetFlags());
   Component component = await compileTestCaseToKernelProgram(source,
       target: target,
       environmentDefines: {
         'test.define.isTrue': 'true',
         'test.define.isFalse': 'false'
       });
-  final evaluator = VMConstantEvaluator.create(
-      target, component, targetOS, nnbdMode,
+  final evaluator = VMConstantEvaluator.create(target, component, targetOS,
       enableAsserts: enableAsserts);
   component = transformComponent(target, component, evaluator, enableAsserts);
   verifyComponent(
diff --git a/pkg/vm/test/transformations/vm_constant_evaluator_test.dart b/pkg/vm/test/transformations/vm_constant_evaluator_test.dart
index b7a893c66d8..de69305db44 100644
--- a/pkg/vm/test/transformations/vm_constant_evaluator_test.dart
+++ b/pkg/vm/test/transformations/vm_constant_evaluator_test.dart
@@ -81,10 +81,7 @@ class TestOptions {
 }
 
 runTestCase(Uri source, TestCase testCase) async {
-  final soundNullSafety = true;
-  final nnbdMode = NnbdMode.Strong;
-  final target =
-      new VmTarget(new TargetFlags(soundNullSafety: soundNullSafety));
+  final target = new VmTarget(new TargetFlags());
   Component component = await compileTestCaseToKernelProgram(source,
       target: target,
       environmentDefines: {
@@ -93,8 +90,7 @@ runTestCase(Uri source, TestCase testCase) async {
       });
 
   final reporter = TestErrorReporter();
-  final evaluator = VMConstantEvaluator.create(
-      target, component, testCase.os, nnbdMode,
+  final evaluator = VMConstantEvaluator.create(target, component, testCase.os,
       enableAsserts: testCase.enableAsserts, errorReporter: reporter);
   late String actual;
   if (testCase.throws) {
diff --git a/runtime/tests/vm/dart/error_messages_in_null_checks_test.dart b/runtime/tests/vm/dart/error_messages_in_null_checks_test.dart
index 30e08eff0b4..6fb5a075f1c 100644
--- a/runtime/tests/vm/dart/error_messages_in_null_checks_test.dart
+++ b/runtime/tests/vm/dart/error_messages_in_null_checks_test.dart
@@ -87,17 +87,7 @@ main(List<String> args) {
           e.toString().startsWith(
               'NoSuchMethodError: The method \'+\' was called on null.'));
 
-  Expect.throws(
-      () => 9.81 - doubleNull,
-      (e) => hasUnsoundNullSafety
-          ? (e is NoSuchMethodError &&
-              // If '-' is specialized.
-              (e.toString().startsWith(
-                      'NoSuchMethodError: The method \'-\' was called on null.') ||
-                  // If '-' is not specialized, it calls toDouble() internally.
-                  e.toString().startsWith(
-                      'NoSuchMethodError: The method \'toDouble\' was called on null.')))
-          : (e is TypeError));
+  Expect.throws(() => 9.81 - doubleNull, (e) => e is TypeError);
 
   Expect.throws(
       () => intNull * 7,
diff --git a/runtime/tests/vm/dart/flutter_regress_91370_il_test.dart b/runtime/tests/vm/dart/flutter_regress_91370_il_test.dart
index bc5c327ff54..aff02f88b57 100644
--- a/runtime/tests/vm/dart/flutter_regress_91370_il_test.dart
+++ b/runtime/tests/vm/dart/flutter_regress_91370_il_test.dart
@@ -617,12 +617,7 @@ void matchIL$testNarrowingThroughIndexedLoadFromGrowableArray(
           match.Redefinition('this'),
           // This redefinition was inserted by load forwarding.
           'a.data[0]*' << match.Redefinition('a.data[0]'),
-          if (!beforeLICM.soundNullSafety)
-            'a.data[0]*!' << match.CheckNull('a.data[0]*'),
-          'a.data[0].str' <<
-              match.LoadField(
-                  beforeLICM.soundNullSafety ? 'a.data[0]*' : 'a.data[0]*!',
-                  slot: 'str'),
+          'a.data[0].str' << match.LoadField('a.data[0]*', slot: 'str'),
         ]),
   ]);
 
@@ -649,12 +644,7 @@ void matchIL$testNarrowingThroughIndexedLoadFromGrowableArray(
         ]),
     'B3' <<
         match.block('Target', [
-          if (!beforeLICM.soundNullSafety)
-            'a.data[0]!' << match.CheckNull('a.data[0]'),
-          'a.data[0].str' <<
-              match.LoadField(
-                  beforeLICM.soundNullSafety ? 'a.data[0]' : 'a.data[0]!',
-                  slot: 'str'),
+          'a.data[0].str' << match.LoadField('a.data[0]', slot: 'str'),
         ]),
   ], env: env);
 }
@@ -692,10 +682,7 @@ void matchIL$testNarrowingThroughIndexedLoadFromFixedArray(
           match.Redefinition('this'),
           // This redefinition was inserted by load forwarding.
           'a[0]*' << match.Redefinition('a[0]'),
-          if (!beforeLICM.soundNullSafety) 'a[0]*!' << match.CheckNull('a[0]*'),
-          'a[0].str' <<
-              match.LoadField(beforeLICM.soundNullSafety ? 'a[0]*' : 'a[0]*!',
-                  slot: 'str'),
+          'a[0].str' << match.LoadField('a[0]*', slot: 'str'),
         ]),
   ]);
 
@@ -721,10 +708,7 @@ void matchIL$testNarrowingThroughIndexedLoadFromFixedArray(
         ]),
     'B3' <<
         match.block('Target', [
-          if (!beforeLICM.soundNullSafety) 'a[0]!' << match.CheckNull('a[0]'),
-          'a[0].str' <<
-              match.LoadField(beforeLICM.soundNullSafety ? 'a[0]' : 'a[0]!',
-                  slot: 'str'),
+          'a[0].str' << match.LoadField('a[0]', slot: 'str'),
         ]),
   ], env: env);
 }
diff --git a/runtime/tests/vm/dart/null_checks_with_dwarf_stack_traces_test.dart b/runtime/tests/vm/dart/null_checks_with_dwarf_stack_traces_test.dart
index 7a87925d72d..98b2e94ee09 100644
--- a/runtime/tests/vm/dart/null_checks_with_dwarf_stack_traces_test.dart
+++ b/runtime/tests/vm/dart/null_checks_with_dwarf_stack_traces_test.dart
@@ -52,10 +52,7 @@ main(List<String> args) {
 
   Expect.throws(() => doubleNull + 2.17, (e) => e is NoSuchMethodError);
 
-  Expect.throws(
-      () => 9.81 - doubleNull,
-      (e) =>
-          hasUnsoundNullSafety ? (e is NoSuchMethodError) : (e is TypeError));
+  Expect.throws(() => 9.81 - doubleNull, (e) => (e is TypeError));
 
   Expect.throws(() => intNull * 7, (e) => e is NoSuchMethodError);
 }
diff --git a/runtime/tests/vm/dart/spawn_uri_from_kernel_blob_test.dart b/runtime/tests/vm/dart/spawn_uri_from_kernel_blob_test.dart
index 9ce3578d391..e2e3a0a8af6 100644
--- a/runtime/tests/vm/dart/spawn_uri_from_kernel_blob_test.dart
+++ b/runtime/tests/vm/dart/spawn_uri_from_kernel_blob_test.dart
@@ -22,7 +22,7 @@ main() async {
   final sourceUri =
       Platform.script.resolve('spawn_uri_from_kernel_blob_script.dart');
   final options = new CompilerOptions()
-    ..target = VmTarget(TargetFlags(soundNullSafety: hasSoundNullSafety))
+    ..target = VmTarget(TargetFlags())
     ..additionalDills = <Uri>[Uri.file(platformDill)]
     ..environmentDefines = {}
     ..nnbdMode = hasSoundNullSafety ? NnbdMode.Strong : NnbdMode.Weak
diff --git a/runtime/tests/vm/dart/transferable_throws_test.dart b/runtime/tests/vm/dart/transferable_throws_test.dart
index c01459a3078..06b105c85e7 100644
--- a/runtime/tests/vm/dart/transferable_throws_test.dart
+++ b/runtime/tests/vm/dart/transferable_throws_test.dart
@@ -99,15 +99,8 @@ main() async {
   throwsIfCumulativeListIsTooLargeOn32bitPlatform();
 
   dynamic myNull;
-  if (hasUnsoundNullSafety) {
-    Expect.throwsArgumentError(() => TransferableTypedData.fromList(myNull));
-    Expect.throwsArgumentError(() => TransferableTypedData.fromList([myNull]));
-    Expect.throwsArgumentError(
-        () => TransferableTypedData.fromList(MyList<Uint8List>()));
-  } else {
-    Expect.throwsTypeError(() => TransferableTypedData.fromList(myNull));
-    Expect.throwsTypeError(() => TransferableTypedData.fromList([myNull]));
-    Expect.throwsTypeError(
-        () => TransferableTypedData.fromList(MyList<Uint8List>()));
-  }
+  Expect.throwsTypeError(() => TransferableTypedData.fromList(myNull));
+  Expect.throwsTypeError(() => TransferableTypedData.fromList([myNull]));
+  Expect.throwsTypeError(
+      () => TransferableTypedData.fromList(MyList<Uint8List>()));
 }