| // Copyright (c) 2015, 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. |
| |
| /** |
| * Ensures that the given [value] is not null. |
| * Otherwise throws an [ArgumentError]. |
| * An optional [description] is used in the error message. |
| */ |
| void notNull(Object value, [String description]) { |
| if (value == null) { |
| if (description == null) { |
| throw new ArgumentError('Must not be null'); |
| } else { |
| throw new ArgumentError('Must not be null: $description'); |
| } |
| } |
| } |