Re: RDFa Lite and non-RDFa @rel values

On Wed, Apr 25, 2012 at 2:31 AM, Ivan Herman <ivan@w3.org> wrote:
> Wow. Lots of mails while I was on the road yesterday...
>
> This is a set of replies to a number of issues in one place; collecting those may help moving forward.
>
> ---
>
> Alex, you said:
>
> [[[
> That means, the real question comes down to what we expect from this
> kind of markup:
>
>  <a vocab="..." href="http://www.w3.org/" rel="nofollow"
> property="homepage">W3C's Home Page</a>
>
> Should it be:
>
>  <> <http://www.w3.org/1999/xhtml/vocab#nofollow> <http://www.w3.org/>
>  <> <...homepage> "W3C's Home Page"
>
> or
>
>  <> <http://www.w3.org/1999/xhtml/vocab#nofollow> <http://www.w3.org/>
>  <> <...homepage> <http://www.w3.org/>
>
> ?
> ]]]
>
> Well, in my view, none of the two. I believe the response should be:
>
> <> <...homepage> <http://www.w3.org/> .
>
> And nothing else.

In HTML5 with the HTML or XHTML syntax?  That's where I start to get
heartburn with all of this.

I've been detailing solely with XHTML documents and so my perspective
is skewed.  The initial context is different and so link relations all
come out nicely as RDFa triples.  I've been enjoying the fact that
they do as link analysis via RDFa is very useful.

The fact is now, with both of these documents, that if you take
exactly the same document and serialize it in the XHTML and HTML
syntaxes, you'll get different RDFa triples.  That bothers me even
more than this current issue.  You can fake some of it by setting the
@vocab attribute but that won't help once you've used it for your own
vocabulary.  You just can't prime the "local default vocabulary"
yourself--only the host language can.  As such, we've treated XHTML
and HTML syntaxes as different host languages when they spring from
the same specification and that seems to be going the wrong direction
as HTML5 has attempted to bring them closer together.

>
> The issue here is that, as we looked at this before, the predefined @rel values make very little semantic sense for RDF. That is the very reason that we did _not_ generate any triples automatically for those guys in HTML5. Hence the proposal of Stéphane to, essentially, drop those from the generated RDF is actually in line with this observation, because they are _not_ meant for RDF. (The user always has the possibility to use a CURIE or a full URI if he/she _wants_ a triple to appear there.)

I think that's a matter of perspective.  Just because a @rel value
doesn't help marking up small structures (e.g. a person) doesn't mean
they don't have value overall for the relationships between documents
on the web.

> ---
> Then there is DanBri's comment that I would like to take very seriously. We need finalization and stability NOW; we are getting to "The perfect is the enemy of the good" effect here. Any delay may seriously backfire as for the acceptance of RDFa. I know this is not a technical argument, but that is where we are...
>

I understand the seriousness of the schedule.

> Bottom line: I am still in favour of Stéphane's option 1. The only other alternative I can live with is to stay with the status quo and move on.

Putting my W3C hat on, doesn't "fixing" that require testing for
non-expansion in section "7.5 Sequence" result in a substantive change
that requires going back to CR?



-- 
--Alex Milowski
"The excellence of grammar as a guide is proportional to the paucity of the
inflexions, i.e. to the degree of analysis effected by the language
considered."

Bertrand Russell in a footnote of Principles of Mathematics

Received on Wednesday, 25 April 2012 14:26:17 UTC