Language/Generics/function_A03_t01.dart

// 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.

// @dart = 2.9

/// @assertion A generic function declaration introduces a generic function into
/// the enclosing scope. Consider a function invocation expression of the form
/// [f<T1, . . . , Tl>(...)], where the static type of [f] is a generic function
/// type with formal type parameters [X1 extends B1], . . . , [Xm extends Bm].
/// ...
/// It is a compile-time error if there exists a [j] such that [Tj] is not a
/// subtype of [T1/X1, . . . , Tm/Xm]Bj.
/// @description checks that error appears if some parameter type is incorrect.
/// @author iarkh@unipro.ru


class A {}
class B extends A {}
class C extends B {}
class D {}

void testme1<T>() {}
void testme2<T extends A>() {}
void testme3<T extends B>() {}
void testme4<T extends C>() {}
void testme5<T extends D>() {}


main() {
  testme1<A>();
  testme1<B>();
  testme1<C>();
  testme1<D>();

  testme2<A>();
  testme2<B>();
  testme2<C>();
  testme2<D>(); //# 01: compile-time error

  testme3<A>(); //# 02: compile-time error
  testme3<B>();
  testme3<C>();
  testme3<D>(); //# 03: compile-time error

  testme4<A>(); //# 04: compile-time error
  testme4<B>(); //# 05: compile-time error
  testme4<C>();
  testme4<D>(); //# 06: compile-time error

  testme5<A>(); //# 07: compile-time error
  testme5<B>(); //# 08: compile-time error
  testme5<C>(); //# 09: compile-time error
  testme5<D>();
}