Language/15_Types/5_Function_Types_A05_t03.dart

/*
 * Copyright (c) 2011, 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 A function is always an instance of some class that implements the class Function.
 * All function types are subtypes of Function.
 * @description Checks that various local functions implement the interface Function.
 * @author iefremov
 * @reviewer rodionov
 */
import "../../Utils/expect.dart";

main() {
  f1() {}
  void f2() {}
  Object f3() {}
  int f4() {}
  f5(var x) {}
  void f6(var x) {}
  String f7([var x]) {}
  Object f8(var x, int z, [Object o, var v = 1]) {}
  Object f9(var x, int z, {o, v: 1}) {}

  Expect.isTrue(f1 is Function);
  Expect.isTrue(f2 is Function);
  Expect.isTrue(f3 is Function);
  Expect.isTrue(f4 is Function);
  Expect.isTrue(f5 is Function);
  Expect.isTrue(f6 is Function);
  Expect.isTrue(f7 is Function);
  Expect.isTrue(f8 is Function);
  Expect.isTrue(f9 is Function);
}