Comments on: DOM 3 XPath in Web Kit

By: geecu

geecu — Tue, 27 Jan 2009 18:11:32 +0000

I’ve tested it (FF and Safari on Mac), //div[@class="class"] is about 20 times *slower* than getElementByClassName. Maybe I was doing something wrong… have you tested it?

By: Bill Humphries

Bill Humphries — Sun, 29 Oct 2006 18:18:45 +0000

@ jmdesp: no doubt that a native version of getElementBySelector would be fast. It’s one of the items the WHAT-WG considering.

But given the choice between Prototype’s getElementsByClassName(), and a native XPath expression, I’ll take the later.

By: jmdesp

jmdesp — Sun, 29 Oct 2006 16:02:37 +0000

I don’t understand. Why would byClassName be more expensive to implement than xpath ? Or is it because you can’t point to exactly what you want and need expensive enumerations ?
Whatever getElementById will always be the fastest choice, and it’s better to reorganise the page in order to use it.