| // Copyright (c) 2017, 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 Iterable<T> expand<T>(Iterable f(E element)) |
| /// ... |
| /// The returned Iterable is lazy, and calls f for each element of this every |
| /// time it's iterated. |
| /// @description Checks that returned Iterable is lazy. |
| /// @author ngl@unipro.ru |
| |
| |
| import "dart:typed_data"; |
| import "../../../Utils/expect.dart"; |
| |
| main() { |
| var l = new Int64List.fromList([1, 2, 3, 4, 5, 6]); |
| var counter = 0; |
| |
| var res = l.expand((element) {counter++; return [element * 2];}); |
| Expect.equals(0, counter); |
| |
| res.elementAt(0); |
| Expect.equals(1, counter); |
| } |