Ian Hickson wrote:
On Tue, 18 Nov 2008, Martin McEvoy wrote:
Just one small question
Why Has HTML5 dropped the rev=""[1] attribute?
[1] http://www.w3.org/TR/html5-diff/#absent-attributes
We did some studies and found that the attribute was almost never used,
and most of the time, when it was used, it was a typo where someone meant
to write rel="" but wrote rev="". To be precise, the most commonly used
value was rev="made", which is equivalent to rel="author" and thus was not
a convincing use case. The second most common value was rev="stylesheet",
which is meaningless and obviously meant to be rel="stylesheet". We
therefore determined that authors would benefit more from the validator
complaining about this attribute instead of supporting it.
(I don't dispute it's relative un-used-ness...)
Anything that could be done with rev="" can be done with rel="" with an
opposite keyword, so this omission should be easy to handle.
This would seem to shift work from HTML5 to relationship vocabulary
specs, whether RDFa-oriented or XFN-based: they'll have to name the
relationship in both directions now.
eg.
john.html:
<p>See my <a rel="father" href="pa.html">dad's page</a> for details</p>
and
pa.html:
<p>See my <a rel="child" href="john.html">son's page</a> for details</p>
are ok in html5, but
pa.html: <p>Reader,<a rev="father" href="john.html">i'm his father</a></p>
So long as there's a plausible inverse defined,
...isn't. I'm not arguing here that this is right or wrong or good or
bad or pretty or ugly, just that the parties defining little
relationship vocabularies such as 'parent', 'child',
'father','mother','brother','ex-line-manager', and so on will (now 'rev'
is going away) need to think carefully about naming each inverse
relationship as well. As you point out, rev= wasn't heavily used anyway;
however technologies like microformats and RDFa are relatively new to
the Web, and things can take a while to get adopted (eg. XHR/'ajax').
cheers,
Dan
a personal ps.:
for some reason, rev= always made my head hurt slightly to even think
about, I guess because there are two senses of a reversed link: the
reversed meaning of a link versus the idea of an incoming link /
backlink, and the difference is simultaneously both obvious and subtle
