Language/Expressions/Unary_Expressions/variable_negative_t03.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 expression !e is equivalent to the expression
 * e ? false : true.
 * @description Checks that, just like with conditional expressions, it is
 * a dynamic type error when e is not a boolean and it is subjected to a boolean
 * conversion
 * @author rodionov
 */
// Requirements=nnbd-strong
import '../../../Utils/expect.dart';
import '../../../Utils/dynamic_check.dart';

main() {
  var v = null;
  checkTypeError(() { Expect.isTrue(!v); });
  v = "true, honestly";
  checkTypeError(() { Expect.isTrue(!v); });
  v = () {};
  checkTypeError(() { Expect.isTrue(!v); });
}