| Index: lib/runtime/dart/_generators.js
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| diff --git a/lib/runtime/dart/_generators.js b/lib/runtime/dart/_generators.js
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| deleted file mode 100644
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| index 442ae736eaa30134fd4fc2b657c1c2235bdfd365..0000000000000000000000000000000000000000
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| --- a/lib/runtime/dart/_generators.js
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| +++ /dev/null
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| @@ -1,234 +0,0 @@
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| -// Copyright (c) 2015, the Dart project authors. Please see the AUTHORS file
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| -// 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.
|
| -
|
| -/**
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| - * This library adapts ES6 generators to implement Dart's async/await.
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| - *
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| - * It's designed to interact with Dart's Future/Stream and follow Dart
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| - * async/await semantics.
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| - *
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| - * See https://github.com/dart-lang/dev_compiler/issues/245 for ideas on
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| - * reconciling Dart's Future and ES6 Promise.
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| - *
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| - * Inspired by `co`: https://github.com/tj/co/blob/master/index.js, which is a
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| - * stepping stone for proposed ES7 async/await, and uses ES6 Promises.
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| - */
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| -dart_library.library('dart/_generators', null, /* Imports */[
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| -], /* Lazy Imports */[
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| - 'dart/_operations',
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| - 'dart/_js_helper',
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| - 'dart/core',
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| - 'dart/collection',
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| - 'dart/async'
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| -], function(exports, _operations, _js_helper, core, collection, async) {
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| - 'use strict';
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| -
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| - const _jsIterator = Symbol('_jsIterator');
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| - const _current = Symbol('_current');
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| -
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| - function syncStar(gen, E, ...args) {
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| - const SyncIterable_E = _js_helper.SyncIterable$(E);
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| - return new SyncIterable_E(gen, args);
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| - }
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| - exports.syncStar = syncStar;
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| -
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| - function async_(gen, T, ...args) {
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| - let iter;
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| - function onValue(res) {
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| - if (res === void 0) res = null;
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| - return next(iter.next(res));
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| - }
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| - function onError(err) {
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| - // If the awaited Future throws, we want to convert this to an exception
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| - // thrown from the `yield` point, as if it was thrown there.
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| - //
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| - // If the exception is not caught inside `gen`, it will emerge here, which
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| - // will send it to anyone listening on this async function's Future<T>.
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| - //
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| - // In essence, we are giving the code inside the generator a chance to
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| - // use try-catch-finally.
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| - return next(iter.throw(err));
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| - }
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| - function next(ret) {
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| - if (ret.done) return ret.value;
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| - // Checks if the awaited value is a Future.
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| - let future = ret.value;
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| - if (!_operations.instanceOf(future, async.Future$)) {
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| - future = async.Future.value(future);
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| - }
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| - // Chain the Future so `await` receives the Future's value.
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| - return future.then(onValue, {onError: onError});
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| - }
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| - return async.Future$(T).new(function() {
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| - iter = gen(...args)[Symbol.iterator]();
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| - return onValue();
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| - });
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| - }
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| - exports.async = async_;
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| -
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| - // Implementation inspired by _AsyncStarStreamController in
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| - // dart-lang/sdk's runtime/lib/core_patch.dart
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| - //
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| - // Given input like:
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| - //
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| - // foo() async* {
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| - // yield 1;
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| - // yield* bar();
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| - // print(await baz());
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| - // }
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| - //
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| - // This generates as:
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| - //
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| - // function foo() {
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| - // return dart.asyncStar(function*(stream) {
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| - // if (stream.add(1)) return;
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| - // yield;
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| - // if (stream.addStream(bar()) return;
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| - // yield;
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| - // print(yield baz());
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| - // });
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| - // }
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| - class _AsyncStarStreamController {
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| - constructor(generator, T, args) {
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| - this.isAdding = false;
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| - this.isWaiting = false;
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| - this.isScheduled = false;
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| - this.isSuspendedAtYield = false;
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| - this.canceler = null;
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| - this.iterator = generator(this, ...args)[Symbol.iterator]();
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| - this.controller = async.StreamController$(T).new({
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| - onListen: () => this.scheduleGenerator(),
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| - onResume: () => this.onResume(),
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| - onCancel: () => this.onCancel()
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| - });
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| - }
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| -
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| - onResume() {
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| - if (this.isSuspendedAtYield) {
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| - this.scheduleGenerator();
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| - }
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| - }
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| -
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| - onCancel() {
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| - if (this.controller.isClosed) {
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| - return null;
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| - }
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| - if (this.canceler == null) {
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| - this.canceler = async.Completer.new();
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| - this.scheduleGenerator();
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| - }
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| - return this.canceler.future;
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| - }
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| -
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| - close() {
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| - if (this.canceler != null && !this.canceler.isCompleted) {
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| - // If the stream has been cancelled, complete the cancellation future
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| - // with the error.
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| - this.canceler.complete();
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| - }
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| - this.controller.close();
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| - }
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| -
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| - scheduleGenerator() {
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| - // TODO(jmesserly): is this paused check in the right place? Assuming the
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| - // async* Stream yields, then is paused (by other code), the body will
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| - // already be scheduled. This will cause at least one more iteration to
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| - // run (adding another data item to the Stream) before actually pausing.
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| - // It could be fixed by moving the `isPaused` check inside `runBody`.
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| - if (this.isScheduled || this.controller.isPaused ||
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| - this.isAdding || this.isWaiting) {
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| - return;
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| - }
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| - this.isScheduled = true;
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| - async.scheduleMicrotask(() => this.runBody());
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| - }
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| -
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| - runBody(opt_awaitValue) {
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| - this.isScheduled = false;
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| - this.isSuspendedAtYield = false;
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| - this.isWaiting = false;
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| - let iter;
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| - try {
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| - iter = this.iterator.next(opt_awaitValue);
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| - } catch (e) {
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| - this.addError(e, _operations.stackTrace(e));
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| - this.close();
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| - return;
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| - }
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| - if (iter.done) {
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| - this.close();
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| - return;
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| - }
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| -
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| - // If we're suspended at a yield/yield*, we're done for now.
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| - if (this.isSuspendedAtYield || this.isAdding) return;
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| -
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| - // Handle `await`: if we get a value passed to `yield` it means we are
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| - // waiting on this Future. Make sure to prevent scheduling, and pass the
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| - // value back as the result of the `yield`.
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| - //
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| - // TODO(jmesserly): is the timing here correct? The assumption here is
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| - // that we should schedule `await` in `async*` the same as in `async`.
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| - this.isWaiting = true;
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| - let future = iter.value;
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| - if (!_operations.instanceOf(future, async.Future$)) {
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| - future = async.Future.value(future);
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| - }
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| - return future.then((x) => this.runBody(x),
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| - { onError: (e, s) => this.throwError(e, s) });
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| - }
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| -
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| - // Adds element to stream, returns true if the caller should terminate
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| - // execution of the generator.
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| - add(event) {
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| - // If stream is cancelled, tell caller to exit the async generator.
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| - if (!this.controller.hasListener) return true;
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| - this.controller.add(event);
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| - this.scheduleGenerator();
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| - this.isSuspendedAtYield = true;
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| - return false;
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| - }
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| -
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| - // Adds the elements of stream into this controller's stream.
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| - // The generator will be scheduled again when all of the
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| - // elements of the added stream have been consumed.
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| - // Returns true if the caller should terminate
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| - // execution of the generator.
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| - addStream(stream) {
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| - // If stream is cancelled, tell caller to exit the async generator.
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| - if (!this.controller.hasListener) return true;
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| -
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| - this.isAdding = true;
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| - this.controller.addStream(stream, {cancelOnError: false}).then(() => {
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| - this.isAdding = false;
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| - this.scheduleGenerator();
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| - }, { onError: (e, s) => this.throwError(e, s) });
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| - }
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| -
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| - throwError(error, stackTrace) {
|
| - try {
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| - this.iterator.throw(error);
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| - } catch (e) {
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| - this.addError(e, stackTrace);
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| - }
|
| - }
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| -
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| - addError(error, stackTrace) {
|
| - if ((this.canceler != null) && !this.canceler.isCompleted) {
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| - // If the stream has been cancelled, complete the cancellation future
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| - // with the error.
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| - this.canceler.completeError(error, stackTrace);
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| - return;
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| - }
|
| - if (!this.controller.hasListener) return;
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| - this.controller.addError(error, stackTrace);
|
| - }
|
| - }
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| -
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| - /** Returns a Stream of T implemented by an async* function. */
|
| - function asyncStar(gen, T, ...args) {
|
| - return new _AsyncStarStreamController(gen, T, args).controller.stream;
|
| - }
|
| - exports.asyncStar = asyncStar;
|
| -});
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|
|