promise concurrency

基于promise 并发控制

Цей скрипт не слід встановлювати безпосередньо. Це - бібліотека для інших скриптів для включення в мета директиву // @require https://update.greasyfork.org/scripts/488850/1336774/promise%20concurrency.js

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(У мене вже є менеджер скриптів, дайте мені встановити його!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==/UserScript==
// @version               1.0
// ==/UserScript==

; (() => {
  /**
   * # 使用方法
   * ```js
   * await concurrentTasks(5, [1, 2, 3, 4], (n) => {
   *   return new Promise((ok) => {
   *     setTimeout(() => {
   *       console.log(n);
   *       ok();
   *     }, Math.random() * 5000);
   *   });
   * });
   * ```
   * @template T
   * @param {number} limit - 并发数
   * @param {T[] | NodeListOf<T>} tasks - 可迭代对象
   * @param {(task:T) => Promise<void>} asyncCallback - Promise 回调函数
   * @returns {Promise<void>}
   */
  const concurrentTasks = async (limit, tasks, asyncCallback) => {
    limit = Math.min(limit, tasks.length);
    let index = 0;
    const run = async () => {
      while (index < tasks.length) {
        await asyncCallback(tasks[index++]);
      }
    };
    const runTaks = Array.from({ length: limit }, () => run());
    await Promise.all(runTaks);
  };

  window.concurrentTasks = concurrentTasks;
})();