Re: [HTML+RDFa 1.1] section 3.1 and 2.1

Olaf,

At the risk of sounding heretical.... if you are really concerned about
future interpretation of your document, just use @version.  True, it will
not validate as an HTML5 nor as an HTML5+RDFa document, but it won't hurt
anything that it does not validate, and it will ensure that conforming RDFa
processors always interpret your document the way you want them to.

I know that is what my company plans to do.


On Thu, Jan 31, 2013 at 6:05 AM, Ivan Herman <ivan@w3.org> wrote:

> Olaf,
>
> To be honest, I am not sure how to solve these issues, and I would welcome
> your suggestions. We face two problems here.
>
> In (X)HTML5 the @version attribute does not exist any more. In previous
> versions of RDFa we made use of that attribute and, actually, RDFa 1.1 Core
> still refers to this attribute for, eg., XHTML1.0. Processors hitting the
> @version value referring to RDFa 1.0, for example, are supposed to process
> accordingly. But, as I said, this option is not available any more in
> (X)HTML5...
>
> Of course, we could define a separate attribute, much like we do have a
> number of RDFa 1.1 attributes. But there comes the next issue: many
> authors, or indeed 'webmaster advices' issued by companies like Facebook,
> ignore that attribute anyway. The practice is that authors do not use it.
> Ie, we did not want to rely on the presence of such attribute to control an
> RDFa processor. Meaning that we have to define a behaviour in the absence
> of any additional hints.
>
> So...
>
> On Jan 31, 2013, at 11:54 , "Dr. Olaf Hoffmann" <Dr.O.Hoffmann@gmx.de>
> wrote:
>
> > Hello,
> >
> > the working draft
> > http://www.w3.org/TR/2012/WD-rdfa-in-html-20121213/
> > as well as this variant from today
> > http://www.w3.org/2010/02/rdfa/sources/rdfa-in-html/
> > contain in section 3.1 the sentence:
> > "Documents served as application/xhtml+xml, that don't contain a DTD, and
> > don't specify a @version attribute must be interpreted as XHTML5+RDFa 1.1
> > documents."
> >
> > Does this mean, that if for example in 20 years I write an XHTML6+RDFa
> 2.0
> > document, there will be a DTD or version indication again to ensure, that
> > the document will be interpreted as XHTML6+RDFa 2.0 and not as
> > XHTML5+RDFa 1.1?
> >
>
> Hopefully RDFa 2.0 would be backward compatible with RDFa 1.1, ie, it
> would not matter (although I know this is not 100% sure with RDFa 1.0/1.1
> :-(. And if this is not the case, then indeed some new attributes may have
> to be used. Actually, this issue will come up regardless of RDFa: What will
> happen with XHTML5 vs. XHTML6? Maybe some mechanism will be introduced by
> the HTML WG of the time to ensure that....
>
> > How to indicate precisely, that a document is of version XHTML5+RDFa 1.1,
> > because section 2.1 only notes:
> > "XML mode XHTML5+RDFa 1.1 documents should be labeled with the Internet
> Media
> > Type application/xhtml+xml as defined in section 12.3 of the HTML5
> > specification [HTML5], must not use a DOCTYPE declaration for XHTML+RDFa
> 1.0
> > or XHTML+RDFa 1.1, and should not use the @version attribute."
> >
> > This does not implicate, how to indicate an XHTML5+RDFa 1.1 at all.
> > Doesn't this finally mean, that one effectively cannot write an
> > XHTML5+RDFa 1.1 document at all, because one cannot indicate, that
> > the document follows this version?
> >
>
> I am not sure I follow your argument. XHTML5+RDFa 1.1 is the 'default' for
> application/xhtml+xml, unless a DTD says otherwise (ie, points at XHTML1
> and/or RDFa 1.0). Of course, if it uses a DTD, it is not XHTML5 any more,
> but it can still be XHTML1.1.
>
> Again, this is primarily an (X)HTML issue, ie, an issue of XHTML5 vs.
> XHTML1.1. RDFa just follows the XHTML5 rules here...
>
> Ivan
>
> > Or should one indicate the relation for example with a DCMI Term
> > (http://dublincore.org/documents/2012/06/14/dcmi-terms/)
> > like conformsTo or  format with the URI of the specification as value?
> > Is this the currently preferred approach for all types of
> (X)HTML5-documents,
> > because they currently have no version indication itself?
> > Or is there a simpler method without the need of other formats to
> > indicate, that one has an (X)HTML5 document and not something else?
> >
> >
> > Olaf
> >
> >
>
>
> ----
> Ivan Herman, W3C Semantic Web Activity Lead
> Home: http://www.w3.org/People/Ivan/
> mobile: +31-641044153
> FOAF: http://www.ivan-herman.net/foaf.rdf
>
>
>
>
>
>


-- 
Shane P. McCarron
Managing Director, Applied Testing and Technology, Inc.