Over in [1] Steve proposes moving the UA requirements for accessibility mapping
out of W3C HTML. The corresponding section in WHATWG HTML is [2].
Recently I tried to do implementer-ey things [3] but found the delineation
between authoring and UA requirements in that section very confusing. So I am
supportive of anything that clears that up.
In the replies to both [1] and [3] Steve points out that the HTML - ARIA
mappings given in [2] are not a complete description of how UAs expose HTML
elements to accessibility technologies, and that the document at [4] is more
accurate. (For example, he notes that figcaption is exposed as a caption to
certain accessibility technologies, but there is no way of expressing that in
ARIA.) So in addition to being confusing, I am not sure the content at [2]
actually has any normative value; at the very least it is incomplete.
In the future I would like to work toward a system where HTML maps to ARIA,
which maps to platform-specific accessibility stuff. So for example ARIA would
grow to have a caption role, and figcaption's accessibility aspects would be
defined entirely by saying it has ARIA role caption. But apparently that is not
the world we live in (yet?!), so I think [2] just confuses the issue by
pretending that it is. In the meantime I think I agree with Steve that [4]
seems to be a better place for implementers to consult.
Thus I think we should remove all UA requirements from [2] and instead refer to
[4] as the authoritative source for UA requirements for accessibility in HTML.
I do not have a strong opinion on whether we should keep the authoring
requirements of [2] intact or remove them as well. This is probably because I
do not have a strong opinion about authoring requirements in general.
What do you think? I could very well be missing something; this world of
accessibility specs is pretty new to me...
[1]: http://lists.w3.org/Archives/Public/public-html/2014Sep/.html
[2]:
http://www.whatwg.org/specs/web-apps/current-work/multipage/dom.html#wai-aria
[3]: http://lists.w3.org/Archives/Public/public-webapps/2014JulSep/0355.html
[4]: http://rawgit.com/w3c/aria/master/html-aam/html-aam.html
