Language/Expressions/Function_Expressions/static_type_form_1_t02.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 The static type of a function literal of the form
 * (T1 a1,...,Tn an, [Tn+1 xn+1 = d1,...,Tn+k xn+k = dk]) => e is
 * (T1,...,Tn, [Tn+1 xn+1,...,Tn+k xn+k]) -> T0, where T0 is the static type
 * of e.
 * In any case where Ti, 1 <= i <= n + k, is not specified, it is considered
 * to have been specified as dynamic.
 * @description Checks that a compile error occurs when assigning a
 * function literal of the form
 * (T1 a1,...,Tn an, [Tn+1 xn+1 = d1,...,Tn+k xn+k = dk]) => e where the type
 * of e is int to a variable of a function type with a boolean return type.
 * @compile-error
 * @author msyabro
 */

typedef bool foo(int x, int y, [double? a, double? b]);

foo? f = null;

main() {
  f = (int x, int y, [double? a, double? b]) => 1;
}