deferred-promise.js

// 1. Deferred
var asyncFn1 = function () {
  var deferred = new Deferred();

  // Initialize async operation and resolve it with either:
  // deferred.resolve or deferred.reject

  return deferred.promise;
};

// 2. Promise
var asyncFn2 = function () {
  return new Promise(function (resolve, reject) {

    // Initialize async operation and resolve it with either:
    // resolve or reject

  });
};