Software update: jQuery 3.1.0

To simplify client-side scripting in HTML, you can use jQuery. This is an open source JavaScript library, whose syntax makes it easier to navigate through documents, select DOM elements, assemble animations, handle events, and of course develop Ajax applications. In addition, the functionality can be extended by using plugins. For more information, please refer to this page. This version 3.1.0 includes fixes that should put an end to silent errors.

jQuery 3.1.0 Released – No More Silent Errors

Not so long ago, we released jQuery 3.0. One of the major features of jQuery 3.0 was a small rewrite of jQuery Deferreds. Specifically, we made them compatible with the Promises/A+ spec. That basically meant that errors had to be silenced and passed as rejection values ​​to rejection handlers (added using deferred.catch()). This had the advantage of preventing Promise handlers from getting blocked up by runtime errors, but the disadvantage of errors being silenced if no rejection handlers were added. While this was the right move for Deferreds, we had also changed jQuery.ready and jQuery.fn.ready to use the new spec-compliant Deferreds under the covers.

Unfortunately, if you were using the usual ways to attach ready handlers (eg jQuery(function() {}) and jQuery(document).ready(function() {})), you had no way to add a rejection handler. Plus, it wasn’t obvious that you were in Deferred land. Any runtime exceptions were getting swallowed and lost in space. I think they ended up somewhere near Pluto, which isn’t even a planet anymore! there were workaroundsbut this wasn’t acceptable to us.

We immediately set out to fix this, and thus jQuery 3.1.0 was born. No longer will errors be silent! You will see them logged to the console by default. If you’d like to have more control on how these errors are handled, we also added an entry point: jQuery.readyException. In most cases, you won’t need to use it, but any errors that are thrown within a ready handler will get passed to this function should you need it.

jQuery.readyException = function(error) { // “error” is thrown from any ready handler };

The default jQuery.readyException will re-throw the error asynchronously, to avoid stopping execution and log the error to the console. We hope this solves any debugging issues you may have experienced when using jQuery 3.0.

We do not expect this release to have any breaking changes, but if you do encounter bugs in upgrading from the previous version, please let us know.

If you’d like help upgrading from jQuery 1.x or 2.x to jQuery 3.0, please check out the 3.0 Upgrade Guide and the jQuery Migrate 1.4.1 blog post.

3.1.0 – GitHub changelog