Comments on CC/PP 2.0 Last Call: RDF/XML restrictions

The Note right before 2.1.2, right after Figure 2-1b refers to the
issues on the RDF/XML encoding and the restrictions thereof.

First of all, I presume the intention was to refer to he RDF/XML Syntax
specification and _not_ the RDFPrimer as said in the note. It already
appears among th normative references under the heading [RDFXML].

However, it is not clear to me whether a more 'crisp' statement is true
or not. Is it correct that the _only_ RDF/XML feature of RDF/XML that is
_not_ allowed in a CC/PP application is the typed node syntax (this is
the way I read the note)? Ie, am I allowed to write something like:

<ccpp:component>
 <rdf:Description
  rdf:about="http://www.example.com/profile#TerminalHardware"
  ex:displayWidth="320" ex:displayHeight="200">
 <rdf:type
    rdf:resource="http://www.example.com/schema#HardwarePlatform" />
 </rdf:Description>
</ccpp:component>

which is, in terms of RDF/XML, equivalent to:
 
<ccpp:component>
 <rdf:Description
  rdf:about="http://www.example.com/profile#TerminalHardware">
  <rdf:type
   rdf:resource="http://www.example.com/schema#HardwarePlatform" />
  <ex:displayWidth>320</ex:displayWidth>
  <ex:displayHeight>200</ex:displayHeight>
 </rdf:Description>
</ccpp:component>

If yes, I think it is worth stating this more clearly (as my sentence
above says). If not... well, then a more systematic list of what is
allowed and what is not allowed should be listed somewhere.

It is of course the decision of the Working Group in which direction the
decision is taken. As far as I am concerned, from an RDF point of view,
I would prefer to require a full acceptance of RDF/XML rather than
defining a subset. But I understand the constraints with UAProf. (I had
a quick look at the UAProf2 document that CC/PP refers to, but it is
also silent on the details of this, by the way)

Note that, strictly speaking, the current spec _violates_ this
restriction! Indeed, the idiom

<ex:htmlVersionsSupported>
  <rdf:Bag>
    <rdf:li>3.2</rdf:li>
    <rdf:li>4.0</rdf:li>
  </rdf:Bag>
</ex:htmlVersionsSupported>

makes use of the type node feature of RDF/XML, ie, in case you maintain
this restriction on RDF/XML, then all your examples should be encoded by

<ex:htmlVersionsSupported>
  <rdf:Description>
    <rdf:type rdf:resource=".....Bag"/>
    <rdf:li>3.2</rdf:li>
    <rdf:li>4.0</rdf:li>
  </rdf:Description>
</ex:htmlVersionsSupported>

-- 

Ivan Herman, W3C Semantic Web Activity Lead
URL: http://www.w3.org/People/Ivan/
PGP Key: http://www.cwi.nl/%7Eivan/AboutMe/pgpkey.html
FOAF: http://www.ivan-herman.net/foaf.rdf