| // 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. | |
| // @dart=2.9 | |
| abstract class I { | |
| void call(); | |
| } | |
| class C implements I { | |
| void call([int x]) {} | |
| } | |
| main() { | |
| I i = new C(); | |
| void Function([int]) f = i; | |
| } |