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std/async/delay.ts

Deno standard library
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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.// This module is browser compatible.
export interface DelayOptions { /** Signal used to abort the delay. */ signal?: AbortSignal; /** Indicates whether the process should continue to run as long as the timer exists. * * @default {true} */ persistent?: boolean;}
/** * Resolve a Promise after a given amount of milliseconds. * * @example * * ```typescript * import { delay } from "https://deno.land/std@$STD_VERSION/async/delay.ts"; * * // ... * const delayedPromise = delay(100); * const result = await delayedPromise; * // ... * ``` * * To allow the process to continue to run as long as the timer exists. Requires * `--unstable` flag. * * ```typescript * import { delay } from "https://deno.land/std@$STD_VERSION/async/delay.ts"; * * // ... * await delay(100, { persistent: false }); * // ... * ``` */export function delay(ms: number, options: DelayOptions = {}): Promise<void> { const { signal, persistent } = options; if (signal?.aborted) return Promise.reject(signal.reason); return new Promise((resolve, reject) => { const abort = () => { clearTimeout(i); reject(signal?.reason); }; const done = () => { signal?.removeEventListener("abort", abort); resolve(); }; const i = setTimeout(done, ms); signal?.addEventListener("abort", abort, { once: true }); if (persistent === false) { try { // @ts-ignore For browser compatibility Deno.unrefTimer(i); } catch (error) { if (!(error instanceof ReferenceError)) { throw error; } console.error("`persistent` option is only available in Deno"); } } });}