// Copyright (c) 2017, 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. | |
class A {} | |
class B extends A {} | |
class C { | |
C operator +(B b) => this; | |
} | |
void main() { | |
C c = new C(); | |
A a = new B(); | |
c += a; | |
// ^ | |
// [analyzer] COMPILE_TIME_ERROR.ARGUMENT_TYPE_NOT_ASSIGNABLE | |
// [cfe] A value of type 'A' can't be assigned to a variable of type 'B'. | |
} |