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Unconsidered way out of ISSUE-30 (@longdesc)

From: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
Date: Tue, 12 Oct 2010 14:54:45 +0200
To: HTML Accessibility Task Force <public-html-a11y@w3.org>, Ian Hickson <ian@hixie.ch>
Cc: HTML4All <list@html4all.org>
Message-ID: <20101012145445388248.d1759cb0@xn--mlform-iua.no>
The Poll for ISSUE-30 considered 3 proposals about @longdesc: Fully 
valid, Valid with a warning and fully invalid. 

A 4th option is that longdesc should be fully valid under the same 
conditions as @usemap is valid. Essentially, this (*currently*) means 
that @longdesc can not be used when there is an anchor element around 
the <img> element. And hence, it would not be a solution to one of the 
justifications for @longdesc: it would not be a solution when/if the 
img is wrapped in an anchor. But it would work otherwise.

Explanation: The following is forbidden in HTML5, but not forbidden in 
HTML4/XHTML1:

    <a href=*><img usemap=#map alt="Lorem ipsum" src=*></a>

Thus, currently, <img longdesc=* > and <img usemap=#* > share destiny: 
neither of them are permitted inside an anchor element. The HTML5 
drafts simply rejects the idea that the there could be a image map 
link, *or* a longdesc link, inside an <img>.  

Justification 1: @longdesc and @usemap should really allowed under the 
same condition because @longdesc and @usemap area conceptually related. 
A valid interpretation of @longdesc is that it turns an <img> into a 
super simple image map, with only one <area> element, and where the 
@coords attribute has been set to coords="0,0,0,0".
Justification 2: It is *another* issue - that could be solved/closed 
separately from ISSUE-30 - that @usemap and @longdesc should be 
permitted also when the <img> is wrapped inside an anchor.

This proposal is thus a compromise in another sense: It limits (as long 
as HTML5 limits @usemap) where @longdesc can be used. But otherwise 
keeps @longdesc fully valid. Thoughts?
-- 
leif halvard silli
Received on Tuesday, 12 October 2010 12:55:21 GMT

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