Language/15_Types/5_Function_Types_A01_t09.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 type (T1,...Tk,[Tk+1,...,Tn+m]) -> T is a subtype of the function
 * type (S1,...,Sk+j,[Sk+j+1,...,Sn]) -> S, if all of the following conditions are met:
 * 1. Either S is void, or T <=> S.
 * 2. For all i 1 <= i <= n, Ti <=> Si.
 * @description Checks that function type t1 is not a subtype of function type t2 if a formal parameter
 * of t1 is not assignable to a corresponding parameter of t2 (both t1 and t2 have a single required formal parameter).
 * @author iefremov
 * @reviewer rodionov
 */
import "../../Utils/expect.dart";

class A {}
class B {}

typedef t1(int a);
typedef t3(A a);
typedef t4(List<A> a);
typedef t5(t1 a);

main() {
  Expect.isFalse((double p) {} is t1);
  Expect.isFalse((bool p) {} is t1);
  Expect.isFalse((A p) {} is t1);
  Expect.isFalse((List<int> p) {} is t1);
  Expect.isFalse((t3 p) {} is t1);

  Expect.isFalse((double p) {} is t3);
  Expect.isFalse((bool p) {} is t3);
  Expect.isFalse((List<int> p) {} is t3);
  Expect.isFalse((t3 p) {} is t3);
  Expect.isFalse((B p) {} is t3);

  Expect.isFalse((double p) {} is t4);
  Expect.isFalse((bool p) {} is t4);
  Expect.isFalse((A p) {} is t4);
  Expect.isFalse((List<int> p) {} is t4);
  Expect.isFalse((List<B> p) {} is t4);
  Expect.isFalse((t3 p) {} is t4);

  Expect.isFalse((double p) {} is t5);
  Expect.isFalse((bool p) {} is t5);
  Expect.isFalse((A p) {} is t5);
  Expect.isFalse((List<int> p) {} is t5);
  Expect.isFalse((t4 p) {} is t5);
}