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Re: Another summary of alt="" issues and why the spec says what it says

From: Jim Jewett <jimjjewett@gmail.com>
Date: Sun, 20 Apr 2008 19:57:42 -0400
Message-ID: <fb6fbf560804201657o2243749bv2dcf92b78363713e@mail.gmail.com>
To: "Leif Halvard Silli" <lhs@malform.no>
Cc: HTML4All <list@html4all.org>, "HTML WG" <public-html@w3.org>, wai-xtech@w3.org

[Individual Cc removed; not sure which lists to trim]

On 4/20/08, Leif Halvard Silli <lhs@malform.no> wrote:
> Jim Jewett 08-04-20 22.44:   

> > On 4/20/08, Leif Halvard Silli <lhs@malform.no> wrote:

> > >  [Snipped the aria-describedby=idref programmatic association benefits.]

> > >  1. Reserved keywords acting as CSS selectors:
> > >  Elements with an ALT attribute or fallback content could have reserved
> > > keywords which would point to the element containing its description: A
> > > "_prev" keyword could point to previous element, a "_next" to next
> element,
> > > a "_parent" to the parent element.

...

>  In my post, I merely thought about the most obvious description selectors,
> and tried to show that one could come a long way only with them.  But if one
> are interested in following this path, then such "alt=_selectors" could be
> made just as advanced as CSS selectors, and thuse _more_ advanced than I
> pereive aria-describedby to be.

Ahh.  That is interesting, particularly since most user agents needs
to implement CSS selectors anyhow.

>  Personally, I think it is a greater risk that a <p id=photo_number_2> would
> become invalid, than there is a risk that <img alt=_next> becomes invalid.

The risk isn't that alt=_next will become a dangling pointer; the risk
is that it will start pointing to a different (and wrong) element.
Since it still points to something, automatic tools won't show the
problem.  Since it only applies to alt (which isn't typically
visible), most designers won't notice on their own.

>  I have problems with understanding why not instead let the association be
> done via identifying a class (something like aria-describedby=class) or
> selector rather by identifying a certain idref.

Would you want 10 elements to all act collectively as the description?

Maybe, but I'm not sure how easy that would be for a UA to handle.

I also suspect we would get quite a few pages like

  <img src=1 alt=_class_photocap>
  <div class=_class_photocap> ... </div>
  <img src=2 alt=_class_photocap>
  <div class=_class_photocap> ... </div>
  <img src=3 alt=_class_photocap>

So which description goes with which photo?

-jJ
Received on Sunday, 20 April 2008 23:58:14 GMT

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