| /* |
| * Copyright (c) 2019, 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. |
| */ |
| /** |
| * @assertion The [==] operator in constant expressions was defined such that |
| * [e1 != null] was only allowed if [e1] had one of the "primitive" system |
| * types. Users had to rewrite their code to [!identical(e1, null)]. This was |
| * changed so that the [==] expression is always allowed as long as one of the |
| * operands is [null]. |
| * @description Checks that compile-time exception is thrown if one of the [!=] |
| * operand is [null] and another one is not a potentially constant. |
| * @compile-error |
| * @author iarkh@unipro.ru |
| */ |
| |
| class A {} |
| A a; |
| |
| main() { |
| const bool a1 = (a != null); |
| } |