unfork DDC's copy of most SDK libraries

pkg/dev_compiler/tool/input_sdk/lib/async/async.dart

-// Copyright (c) 2012, 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.
-
-/**
- * Support for asynchronous programming,
- * with classes such as Future and Stream.
- *
- * Understanding [Future]s and [Stream]s is a prerequisite for
- * writing just about any Dart program.
- *
- * To use this library in your code:
- *
- *     import 'dart:async';
- *
- * ## Future
- *
- * A Future object represents a computation whose return value
- * might not yet be available.
- * The Future returns the value of the computation
- * when it completes at some time in the future.
- * Futures are often used for potentially lengthy computations
- * such as I/O and interaction with users.
- *
- * Many methods in the Dart libraries return Futures when
- * performing tasks. For example, when binding an HttpServer
- * to a host and port, the `bind()` method returns a Future.
- *
- *      HttpServer.bind('127.0.0.1', 4444)
- *          .then((server) => print('${server.isBroadcast}'))
- *          .catchError(print);
- *
- * [Future.then] registers a callback function that runs
- * when the Future's operation, in this case the `bind()` method,
- * completes successfully.
- * The value returned by the operation
- * is passed into the callback function.
- * In this example, the `bind()` method returns the HttpServer
- * object. The callback function prints one of its properties.
- * [Future.catchError] registers a callback function that
- * runs if an error occurs within the Future.
- *
- * ## Stream
- *
- * A Stream provides an asynchronous sequence of data.
- * Examples of data sequences include individual events, like mouse clicks,
- * or sequential chunks of larger data, like multiple byte lists with the
- * contents of a file
- * such as mouse clicks, and a stream of byte lists read from a file.
- * The following example opens a file for reading.
- * [Stream.listen] registers a callback function that runs
- * each time more data is available.
- *
- *     Stream<List<int>> stream = new File('quotes.txt').openRead();
- *     stream.transform(UTF8.decoder).listen(print);
- *
- * The stream emits a sequence of a list of bytes.
- * The program must interpret the bytes or handle the raw byte data.
- * Here, the code uses a UTF8 decoder (provided in the `dart:convert` library)
- * to convert the sequence of bytes into a sequence
- * of Dart strings.
- *
- * Another common use of streams is for user-generated events
- * in a web app: The following code listens for mouse clicks on a button.
- *
- *     querySelector('#myButton').onClick.listen((_) => print('Click.'));
- *
- * ## Other resources
- *
- * * The [dart:async section of the library tour][asynchronous-programming]:
- *   A brief overview of asynchronous programming.
- *
- * * [Use Future-Based APIs][futures-tutorial]: A closer look at Futures and
- *   how to use them to write asynchronous Dart code.
- *
- * * [Futures and Error Handling][futures-error-handling]: Everything you
- *   wanted to know about handling errors and exceptions when working with
- *   Futures (but were afraid to ask).
- *
- * * [The Event Loop and Dart](https://www.dartlang.org/articles/event-loop/):
- *   Learn how Dart handles the event queue and microtask queue, so you can
- *   write better asynchronous code with fewer surprises.
- *
- * * [test package: Asynchronous Tests][test-readme]: How to test asynchronous
- *   code.
- *
- * [asynchronous-programming]: https://www.dartlang.org/docs/dart-up-and-running/ch03.html#dartasync---asynchronous-programming
- * [futures-tutorial]: https://www.dartlang.org/docs/tutorials/futures/
- * [futures-error-handling]: https://www.dartlang.org/articles/futures-and-error-handling/
- * [test-readme]: https://pub.dartlang.org/packages/test
- */
-library dart.async;
-
-import "dart:collection";
-import "dart:_internal" show printToZone, printToConsole,
-                             IterableElementError;
-
-part 'async_error.dart';
-part 'broadcast_stream_controller.dart';
-part 'deferred_load.dart';
-part 'future.dart';
-part 'future_impl.dart';
-part 'schedule_microtask.dart';
-part 'stream.dart';
-part 'stream_controller.dart';
-part 'stream_impl.dart';
-part 'stream_pipe.dart';
-part 'stream_transformers.dart';
-part 'timer.dart';
-part 'zone.dart';