Re: Validating XHTML with embedded RDF

Joseph Reagle <reagle@w3.org> wrote:

> > the RDF Core WG seems to have rejected the XML Schema WG's comments
> > to develop a single canonical syntax which could be more XML Schema
> > or DTD friendly [13] as "beyond the scope of RDF Core's current
> > charter". 
> 
> My sense in talking to RDF folks is that no new syntaxes (even restricted 
> profiles?) should be expected, but perhaps they could correct me.

That's my feeling, too.  Therefore, if "the RDF MUST NOT have to be
reformatted from RDF/XML" is still a requirement and if they still
want some kind of validation, we are stuck in a difficult situation.

> > That largely depends on the RDF Core WG.  The HTML WG can offer help
> > to combine DTD modules, once an RDF DTD module becomes available.
> > However, the HTML WG is not the right group to decide which sort of
> > (restricted) serialization format for RDF is appropriate.  We need
> > input from RDF folks.
> 
> Right, and it appears they have "postponed" the "canonical serialization" 
> issue:
>   http://lists.w3.org/Archives/Public/www-rdf-comments/2003AprJun/0112.html

One caution on this message is that the HTML WG will NOT define
generic syntax.  That's beyond the scope of the HTML WG charter, too.
Our scope is restricted to improve the meta element in XHTML 2.0,
and nothing more.  It *could* be used to encode RDF in XHTML 2.0, but
expressing every possible RDF with this syntax may not be the goal.
Abstract section of the XHTML 2.0 spec clearly says as follows [16]:

   ... it does not attempt to be all things to all people, supplying
   every possible markup idiom, but to supply a generally useful set
   of elements.

We'd try to satisfy 80% of people's typical needs with simple markup.
Supporting every possible corner case is not our design goal.  And
again, this is for XHTML 2.0, not for earlier versions.

> > Technically it is still possible to "use" character entities together
> > with XML Schema or other schema languages, independent from a particular
> > document type definition, as noted in "An XML Core WG View" [15].
> 
> Ah, I hadn't noticed that before. Did the HTML WG respond? The Core position 
> relies upon the presence of a DTD, "The existing mechanism, DTDs, is 
> entirely adequate to the purpose. " [15] Of course, if you don't want to 
> use a DTD, they don't address the issue.

Quoting Ann Navarro, we are "so glad that they can declare things with
such absoluteness" [17].  It's like saying "existing methods suffice
to put RDF in XHTML, there is absolutely no need to introduce a new
mechanism".  We can solve the problem by declaring that there's no
problem.  You can read through the public responses to their "view"
on XML-DEV, starting from John Cowan's announcement [18].

> > [15] http://www.w3.org/XML/Core/2002/10/charents-20021023

[16] http://www.w3.org/TR/2003/WD-xhtml2-20030506/#abstract
[17] http://lists.w3.org/Archives/Member/w3c-html-wg/2002OctDec/0155
     (W3C Members only)
[18] http://lists.xml.org/archives/xml-dev/200210/msg01795.html

Regards,
-- 
Masayasu Ishikawa / mimasa@w3.org
W3C - World Wide Web Consortium

Received on Wednesday, 25 June 2003 03:11:38 UTC