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Re: Request for review of alt and alt value for authoring or publishing tools

From: Joshue O Connor <joshue.oconnor@cfit.ie>
Date: Tue, 15 Apr 2008 22:44:54 +0100
Message-ID: <480521D6.3070400@cfit.ie>
To: Ian Hickson <ian@hixie.ch>
Cc: John Foliot <foliot@wats.ca>, 'Tomas Caspers' <tomas@tomascaspers.de>, wai-xtech@w3.org, wai-liaison@w3.org, public-html@w3.org, 'HTML4All' <list@html4all.org>

Ian Hickson wrote:
> There is *absolutely no practical difference* to the UA between omitting 
> the alt="" attribute altogether, and having the alt="" attribute set to 
> some magical reserved value. They are functionally identical, and user 
> agents can get as much information from either.

Thats not entirely true. If you consider a UA like a screen reader which 
will pretty much by default skip images that have a null alt value and 
the other situation you cite where there is some reserved value that 
will potentially trigger some kind of behaviour (which is undefined as 
yet). The difference (an benefit) of this magical reserved value is that 
the user may be able to choose to also ignore it via some verbosity 
settings. Without this 'magical reserved value' the screen reader will 
potentially default into heuristic evaluation which is not desirable 
when interacting with an application - such as the much vaunted photo 
sharing application - and its dynamically generated/random alphanumeric 
URLs. [1]

So while in principle there may be no practical difference to the UA, 
and I see your point, there is potential for a very real impact on the user.

Cheers

Josh

[1] http://www.paciellogroup.com/resources/articles/altinhtml5.html#apply1
Received on Tuesday, 15 April 2008 21:45:52 UTC

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