Language/Expressions/Maps/key_value_equals_operator_t01.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 It is a compile-time error if the key of an entry in a constant
 * map literal is an instance of a class that implements the operator == unless
 * the key is a string or integer, a literal symbol or the result of invoking a
 * constant constructor of class Symbol.
 * @description Checks that compile-error is produced for const
 * Map<dynamic,dynamic> literal that contains a non-string, non-integer key
 * whose class implements operator ==.
 * @compile-error
 * @author ilya
 */

class C {
  const C();
  bool operator ==(other) => true;
}

main() {
  var x = const {const C(): 1};
}