57 lines
1.8 KiB
TypeScript
57 lines
1.8 KiB
TypeScript
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// (C) Copyright 2015 Moodle Pty Ltd.
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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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import { CorePromise } from '@classes/promise';
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/**
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* Promise whose execution can be cancelled.
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*/
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export class CoreCancellablePromise<T = unknown> extends CorePromise<T> {
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/**
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* Create a new resolved promise.
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*
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* @returns Resolved promise.
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*/
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static resolve(): CoreCancellablePromise<void>;
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static resolve<T>(result: T): CoreCancellablePromise<T>;
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static resolve<T>(result?: T): CoreCancellablePromise<T> {
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return new this(resolve => result ? resolve(result) : (resolve as () => void)(), () => {
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// Nothing to do here.
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});
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}
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protected cancelPromise: () => void;
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constructor(
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executor: (resolve: (value: T | PromiseLike<T>) => void, reject: (reason?: Error) => void) => void,
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cancelPromise: () => void,
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) {
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super(new Promise(executor));
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this.cancelPromise = cancelPromise;
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}
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/**
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* Cancel promise.
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*
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* After this method is called, the promise will remain unresolved forever. Make sure that after calling
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* this method there aren't any references to this object, or it could cause memory leaks.
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*/
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cancel(): void {
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this.cancelPromise();
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}
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}
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