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// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.// TODO(ry) It'd be better to make Deferred a class that inherits from// Promise, rather than an interface. This is possible in ES2016, however// typescript produces broken code when targeting ES5 code.// See At the time of writing, the github issue is closed but the problem remains.export interface Deferred<T> extends Promise<T> { resolve: (value?: T | PromiseLike<T>) => void; // deno-lint-ignore no-explicit-any reject: (reason?: any) => void;}
/** Creates a Promise with the `reject` and `resolve` functions * placed as methods on the promise object itself. It allows you to do: * * const p = deferred<number>(); * // ... * p.resolve(42); */export function deferred<T>(): Deferred<T> { let methods; const promise = new Promise<T>((resolve, reject): void => { methods = { resolve, reject }; }); return Object.assign(promise, methods) as Deferred<T>;}