About test 13 (client side image-maps)

Hi,

Trying to formalize rule 13 at
http://www.w3.org/WAI/GL/WCAG20/tests/test13.html (All links in all
client side image-maps are duplicated within the content), I found that:

* It could be formalized with the following XQuery expression:
//area[let $href:= self::area/@href return count(//a[@href = $href]) = 0] 
= ()

(which says that every area must have a redundant link somewhere else in
the document with the same href attribute; otherwise there is an error.)

* However http://www.w3.org/TR/WCAG20-HTML-TECHS/#csim_textlinks is
deprecated.

* I don't think it is necessary. //area[not(@alt)] = () should be enough.

So, this is confusing.

Comments?

Vicente Luque Centeno
Dep. Ingeniería Telemática
Universidad Carlos III de Madrid
http://www.it.uc3m.es/vlc