Previously, we inferred the return type of statements in a way that made it
impossible to prove the statement typing consistency. Now, we use just the
stated return type for checking statements.
The proofs of statement typing are complete, except for one result generalizing
the expression typing consistency result to multiple variables changing; this
result is obvious to see directly from the provided lemmas but very tedious to
prove in Coq.
Bug:
Change-Id: I0bbcfb613df7510015f278fa85021ba0b3e57503
Reviewed-on: https://dart-review.googlesource.com/9020
Reviewed-by: Dmitry Stefantsov <dmitryas@google.com>
* The definition of the well-formedness property for
configurations is added.
* The theorem that states that the abstract CESK-machine can
make one transition step from any well-formed configuration
is defined and proven.
* Execution of a variable declaration statement is added to
the operational semantics formalization with all necessary
changes (one new eval configuration, three new transition
rules).
* Some auxiliary theorems are added. One of them states that
any runtime value has its method bodies in the function
environment.
Change-Id: I95f233a4db498ce0df76983d9e605c3c263100bb
Reviewed-on: https://dart-review.googlesource.com/7266
Reviewed-by: Samir Jindel <sjindel@google.com>
Summary:
Common datastructures used by both the Kernel AST definition and the object
model are factored into a shared module. A monad for partial computation is
defined to allow us to factor out termination proofs and syntactic validity
checks from the type checking and subtyping relations.
Test Plan:
Ran through coqc.
Bug:
Change-Id: I884666d7cc5b757d62541a46b868f8579a06f011
Reviewed-on: https://dart-review.googlesource.com/4700
Reviewed-by: Dmitry Stefantsov <dmitryas@google.com>
Dmitry Stefantsov