| // Copyright (c) 2020, 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 |
| |
| import "package:expect/expect.dart"; |
| |
| // Test that it is possible to invoke an object whose type is a proper subtype |
| // of a function type (that is, its type is 'function-type bounded', and we |
| // get to call it as if its type had been that bound). |
| |
| class A<X, Y extends X Function(X)> { |
| final Y f; |
| A(this.f); |
| X m(X value) => f(value); |
| } |
| |
| class B extends A<String, String Function(String, {int i})> { |
| B(String Function(String, {int i}) f) : super(f); |
| String m(String value) => f(value, i: 42); |
| } |
| |
| void main() { |
| B b = B((String s, {int i}) => "$s and $i"); |
| Expect.equals('24 and 42', b.m('24')); |
| } |