Re: Do we need the restrictions on the <base> element?

• From: Boris Zbarsky <bzbarsky@MIT.EDU>
• Date: Sun, 03 Jun 2007 14:22:24 -0500
• To: Laurens Holst <lholst@students.cs.uu.nl>
• CC: HTML WG <public-html@w3.org>
• Message-ID: <466314F0.1050501@mit.edu>

Laurens Holst wrote:
> This is very fast O(log n) worst-time, and often faster. And you don’t 
> need to evaluate it very often.

It needs to be either evaluated every time someone sets .src on an image or 
cached on images.  The first way makes an O(1) operation (image swapping) O(log 
N), while the second one makes the memory usage much bigger.

Not to mention all the other elements that use URI attributes...

Note that none of this involved _modifying_ xml:base attributes.  When that 
happens, things are really bad.  But even their mere existence makes 
modification of other attributes and moving of nodes in the DOM more expensive.

> Note that this handler already exists because <img> tags and such needs 
> to respond to changes to the HTML Base element.

Do they?  I don't believe UAs do that.

-Boris

Received on Sunday, 3 June 2007 19:22:43 UTC