// Copyright (c) 2018, the Dart project authors. Please see the AUTHORS file // for details. All rights reserved. Use of this source code is governed by a // BSD-style license that can be found in the LICENSE file. import 'dart:async'; class A implements FutureOr {} // ^^^^^^^^^^^ // [analyzer] COMPILE_TIME_ERROR.SUBTYPE_OF_DISALLOWED_TYPE // ^ // [cfe] The type 'FutureOr' can't be used in an 'implements' clause. void main() { A a = new A(); }