|  | // 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. | 
|  |  | 
|  | import "package:expect/expect.dart"; | 
|  | import "package:async_helper/async_helper.dart"; | 
|  |  | 
|  | range(start, end) async* { | 
|  | for (int i = start; i < end; i++) { | 
|  | yield i; | 
|  | } | 
|  | } | 
|  |  | 
|  | concat(a, b) async* { | 
|  | yield* a; | 
|  | yield* b; | 
|  | } | 
|  |  | 
|  | test() async { | 
|  | Expect.listEquals( | 
|  | [1, 2, 3, 11, 12, 13], await concat(range(1, 4), range(11, 14)).toList()); | 
|  | } | 
|  |  | 
|  | main() { | 
|  | asyncStart(); | 
|  | test().then((_) { | 
|  | asyncEnd(); | 
|  | }); | 
|  | } |