hc-materials/es/core/defer.js

基于react的通用组件库

// + 把promise封装成Deferred，参考jQuery.Deffered
// > see: https://developer.mozilla.org/en-US/docs/Mozilla/JavaScript_code_modules/Promise.jsm/Deferred
export function Deferred() {
  var _this = this;

  var PromiseUtils = window.PromiseUtils || {}; // #! update 062115 for typeof

  if (typeof Promise !== 'undefined' && Promise.defer) {
    // #! need import of Promise.jsm for example: Cu.import('resource:/gree/modules/Promise.jsm');
    return Promise.defer();
  } else if (typeof PromiseUtils !== 'undefined' && PromiseUtils.defer) {
    // #! need import of PromiseUtils.jsm for example: Cu.import('resource:/gree/modules/PromiseUtils.jsm');
    return PromiseUtils.defer();
  } else {
    /* A method to resolve the associated Promise with the value passed.
     * If the promise is already settled it does nothing.
     *
     * @param {anything} value : This value is used to resolve the promise
     * If the value is a Promise then the associated promise assumes the state
     * of Promise passed as value.
     */
    this.resolve = null;
    /* A method to reject the assocaited Promise with the value passed.
     * If the promise is already settled it does nothing.
     *
     * @param {anything} reason: The reason for the rejection of the Promise.
     * Generally its an Error object. If however a Promise is passed, then the Promise
     * itself will be the reason for rejection no matter the state of the Promise.
     */

    this.reject = null;
    /* A newly created Pomise object.
     * Initially in pending state.
     */

    this.promise = new Promise(function (resolve, reject) {
      _this.resolve = resolve;
      _this.reject = reject;
    });
    Object.freeze(this);
  }
}