33 lines
940 B
TypeScript
33 lines
940 B
TypeScript
/**
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* Copyright 2020 Google Inc. All rights reserved.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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export class TaskQueue {
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private _chain: Promise<void>;
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constructor() {
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this._chain = Promise.resolve();
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}
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postTask<T>(task: () => Promise<T>): Promise<T> {
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const result = this._chain.then(task);
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this._chain = result.then(
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() => undefined,
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() => undefined
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);
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return result;
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}
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}
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