- From: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
- Date: Sun, 26 Feb 2012 19:51:16 +0100
- To: Steve Faulkner <faulkner.steve@gmail.com>
- Cc: HTML Accessibility Task Force <public-html-a11y@w3.org>, public-html@w3.org, Judy Brewer <jbrewer@w3.org>, Janina Sajka <janina@rednote.net>
Steve Faulkner, Sun, 26 Feb 2012 08:56:39 -0800:
>> As result, there will be nil -
>> zero - normative requirements -
>
> no there will be the machine checkable requirements
> presence or lack of the alt attribute.
OK. So on/off validation, like in HTML4: Only a check of whether the
alt attribute is present but no check of its content. That would touch
many issues and subjects that we have debated - like the claims that it
is sometimes better to not offer any @alt. One could argue that HTML5's
current approach, were there is no simple predicability about whether
it validate to not drop the @alt, is better. So the CP should probably
explain why this change would be better.
On the other side: The current HTML5-conformance validation — like the
HTML4 validation — has a 'loop hole subset': Presence of an empty alt
attribute, will always make the img validate - regardless of generator
string or other gotchas. So, while an HTML5 validator will display an
error for
<a href=foo ><img src=bar ></a>
it will not display an error for
<a href=foo ><img src=bar alt='' ></a>
Thus, the simple route to validity, for lazy authors and authoring
tools, remains to include an empty alt=''.
I guess this speaks in favor of the change you have worked on. But then
again, it could perhaps also be possible to plug this hole in the HTML5
validation - e.g. by making the latter example an error.
--
Leif H Silli
Received on Sunday, 26 February 2012 18:51:50 UTC