Language/Expressions/Null/instance_of_class_null_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 null object is the sole instance of the built-in class Null.
/// @description Checks that type of null is Null type.
/// @author ngl@unipro.ru

import '../../../Utils/expect.dart';

class A {}

main() {
  var n = null;
  Expect.isTrue(Null is Type);
  Expect.isTrue(null is Null);
  Expect.isTrue(n is Null);
  Expect.isFalse(null is A);
  Expect.isFalse(n is A);
  Expect.runtimeIsType<Type>(Null);
  Expect.runtimeIsType<Null>(null);
  Expect.runtimeIsType<Null>(n);
  Expect.runtimeIsNotType<A>(null);
  Expect.runtimeIsNotType<A>(n);
}