ES2015 Promise

es2015-promise.js

var dates = [1, 2, 3];
var done = dates.map(function (date) {
 return new Promise(function (resolve, reject) {
  var json = ['a', 'b', 'c'];
  if (date > Math.random() * 10) {
   setTimeout(reject, Math.random() * 5000, date);
  }else {
   setTimeout(resolve, Math.random() * 5000, json[Math.ceil(Math.random() * 3) - 1]);
  }
 });
});

Promise.all(done).then(function (value) {
 console.log('Success: ');
 console.log(value);
}).catch(function (reason) {
 console.log('Failed! Reason: ');
 console.log(reason);
});