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Comment by wesley | Hacker News Reader

Can anyone tell me what new features can still be added to jquery? It looks pretty feature complete to me.

I wish they focused more on jquery-ui, as I find that a bit lacking at the moment.

We aren't really talking about the features of this release, yet, since we want people to focus on testing (to make sure we didn't break anything). But here's a rough breakdown of the code that's in:

New Selector Engine (Sizzle: http://github.com/jeresig/sizzle/tree/master). Much faster than previous engine, going to be in many of the major libraries.

No more browser sniffing (currently being discussed here: http://www.reddit.com/r/programming/comments/7l2mr/jquery_re...).

.closest() method - extremely useful for event delegation.

    // Returns this or closest ancestor that matches selector
    $(this).closest("div");

.live() - Super-simple event delegation.

    // Will handle clicks on all elements that match selector
    // even if new ones are added later
    $("#foo > div").live("click", someFn);

.offset() rewrite - significantly faster, uses no browser sniffing.

.hide()/.show() rewrite - 50% - 200% faster.

.append/prepend/before/after rewrite - 10-15x faster.

While the biggest feature of this release is performance, the new event delegation methods are going to be super-useful.

As to jQuery UI - there are multiple teams within the jQuery project - the core jQuery team works on the jQuery library and the jQuery UI team works on jQuery UI. In their last update (about a week ago) the UI team said that UI 1.6 final was going to be out before the end of the month.

Would you consider adding something like .live() for CSS? (Or maybe it already does that.)

Unfortunately it's not as simple as it is with events. With events you have the advantage of binding to a single point (e.g. the document node) and using the native event bubbling that exists in all browsers to capture any event that occurs on the page. This way we can detect a click on a new DOM element that we haven't seen before.

We don't have that luxury with CSS. There's no universal way for all browsers to let JavaScript know when a new element has been added to the page - or that it's been moved. There's the W3C DOM mutation events but they aren't implemented everywhere.

More info: http://www.w3.org/TR/DOM-Level-2-Events/events.html#Events-e...

What? I thought you could just edit the stylesheet object.

Thanks for your quick response.

Well, we could certainly inject new stylesheet rules but that's bound to cause problems since we're at the mercy of the browser CSS engines. I suspect that most jQuery users enjoy writing selectors like "div:first > span" which will be completely null-and-void once we step out of our protected JavaScript garden. Since we can't get full API compatibility it really makes the prospect not very exciting for us.

I'm really happy with these recent upgrades. Especially in regards to event delegation, not having an effective baked in solution for event delegation was one of my biggest complaints about the previous releases.

Yum, I'm glad .live() is in the core.

How different is .live() from .bind()? does this mean we do not have to .unbind() and .bind() when we want to create events for dynamically created DOM elements?

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