Mastering JavaScript Promises

Making progress with promises

Unlike other libraries, a promise has a unique communication ability. It can update you on its progress if you want it to talk to you. Preferably, these are notifications programmed by developers in a way that it can notify them on specified intervals of time to tell them what is the progress. We can do it by using our favorite then() function:

return uploadFile()
.then(function () {
    // Success uploading the file 
}, function (err) {
    // There was an error, and we get the reason for error 
}, function (progress) {
    // this is where I am reporting back my progress. executed 
});

There are more than enough advantages of using Q. For this specific topic, it provides us a short call progress which minimizes our effort to only ...