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Re: Reviewing Last Call RDFa

From: Ralph R. Swick <swick@w3.org>
Date: Thu, 19 Jun 2008 14:21:23 -0400
Message-Id: <>
To: Tim Berners-Lee <timbl@w3.org>
Cc: public-rdf-in-xhtml-tf@w3.org, XHTML WG <public-xhtml2@w3.org>

At 08:54 AM 6/18/2008 -0400, Tim Berners-Lee wrote:
>You could say, (2) "All servers MUST put the namespace GRDDL, and  
>clients MAY use namespace GRDDL, or may use inherent knowledge of the  
>spec." That would work in all cases.
>So I suspect you want go with (2).  To define RDFa conformance.   
>Obviously, people might want to make documents in the short term which  
>work equally well by conforming to the GRDDL spec (document profile  
>method) and by RDFa but that is a distraction.

In today's telecon, the group resolved the following editorial change
in section 4.1 Document Conformance [1]:

  RESOLUTION: move the two items "SHOULD be a DOCTYPE" and
  "SHOULD be a @profile" from Section 4.1 to a new Informational
  Appendix "Deployment Advice"
    -- http://www.w3.org/2008/06/19-rdfa-minutes.html#item01

  [1] http://www.w3.org/TR/2008/WD-rdfa-syntax-20080221/#docconf

The intent of this change is to reinforce that the use of the GRDDL
namespace transform is sufficient to declare that the triples
specified in this document are part of the document semantics.
This was the intent of the language in the Last Call Working Draft.


>This concern is, how do I know that an RDFa  
>reader will not extract triples from a pre-RDFa HTML document
>that  were not intended by the author?

The Working Group's position is that the triples extracted by the
current processing model from existing XHTML1 documents are
the RDF expression of semantics that have been in the HTML
specification.  (I understand that you recalled a demonstration
over a year ago of a prototype RDFa processor that extracted
more triples than are specified by this RDFa processing model.
Those triples were not part of an RDFa Working Draft and are
not part of this RDFa Last Call specification and therefore not
part of the document semantics as defined by RDFa.)

>>We only mean this to enable RDFa processors to also process  
>>microformats, if they so choose.
>Ah I see.  "Default graph" -- the meaning of the document.  if someone  
>makes some RDFb spec, can it not add more triples still?
>>We felt that not leaving this door open might lead some folks to  
>>interpret RDFa as ruling out an RDF interpretation for microformats,  
>>which is not our intention.
>>We could not find a cleaner way to phrase it without making the spec  
>>much more complicated.
>well, just writing that explanation helped me -- maybe it could go in  
>the spec informationally.
>...  i think the  
>important thing is that the RDFa-derived graph is seen as being  
>asserted by the document, but other things can also be. I think we  
>agree on that.  I don't think the text in the spec conveyed it.

The group additionally resolved the following editorial change
in section 4.3. RDFa Processor Conformance [2].

  "RESOLUTION: Replace sentence "This is called the [default graph]"
  with "This specification uses the term <tref>default graph</tref> to
  mean all of the triples asserted by a document according to the
  <a href="#s_model">Processing Model</a> section."
  -- http://www.w3.org/2008/06/19-rdfa-minutes.html#item02

  [2] <http://www.w3.org/TR/2008/WD-rdfa-syntax-20080221/#processorconf>

Received on Thursday, 19 June 2008 18:41:32 UTC

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