W3C home > Mailing lists > Public > public-rdf-in-xhtml-tf@w3.org > October 2006

Re: Reification support in RDFa

From: Dan Brickley <danbri@danbri.org>
Date: Tue, 17 Oct 2006 01:06:01 +0100
Message-ID: <45341E69.6080104@danbri.org>
To: Dan Connolly <connolly@w3.org>
Cc: Elias Torres <elias@torrez.us>, public-rdf-in-xhtml task force <public-rdf-in-xhtml-tf@w3.org>

Dan Connolly wrote:
> On Mon, 2006-10-16 at 17:32 -0400, Elias Torres wrote:
>> During today's meeting we were discussing our current support for RDF
>> reification in our current syntax draft [1] which states:
>>
>> [[[During subject resolution (which could be triggered by object
>> resolution for a rev attribute), the processor may traverse up the DOM
>> tree in search of an about  attribute. If a link or meta element is
>> encountered before an about attribute is found, and if this link or meta
>> element itself does not have an about attribute, then the subject (or,
>> again in the case of rev, object) is resolved as the [RDF/A statement]
>> represented by this link or meta  element.]]]
> 
> I'm not fond of specifying meaning of documents in terms
> of behavior of software ("the processor may...") but the example
> that followed makes it pretty clear what's going on; and what's
> going on falls completely within RDF as specified in the 2004
> Recommendations. The turtle output is completely ordinary RDF:
> 
>  <> cc:license <http://creativecommons.org/licenses/by-nc-nd/2.5/> .
>  <> dc:creator "Mark Birbeck."  
>  _:a rdf:type rdf:Statement .
>  _:a rdf:subject <> .
>  _:a rdf:predicate cc:license .
>  _:a rdf:object <http://creativecommons.org/licenses/by-nc-nd/2.5/> .
>  _:a dc:creator "Ben Adida" .
> 
> 
>> The main discussion point was who are the folks (such as IPTC and others
>> from HTML WG) asking for reification and what the real requirement is
>> for RDFa. Additionally, I brought up the point that the reification [2]
>> vocabulary is not either clearly defined, implemented or used today and
>> that we must be careful on taking on such a task.
> 
> I think it's reasonably well defined. It does not meet quoting
> requirements, but the example in this RDFa draft doesn't involve
> real quoting.
> 
> 
>>  Reification in RDF M&S
>> leans towards identification of statements as opposed to quotation [3].
>> It's not clear which one we want in RDFa.
> 
> I don't see anything that suggests you want quotation. What
> am I missing?
> 
>> I'd like for us (everyone) to discuss more how do we really want to
>> approach reification in RDFa, especially since we have a better
>> situation due to us dealing with HTML documents. We have documents being
>> published on the web at specific locations and I think we have different
>> two major ways to frame the issue/requirement. We might want to track
>> provenance at the HTML/element level (e.g. who wrote what piece of HTML)
>> vs at the RDF level (who said which triple). I think one option is for
>> us to establish our purpose and provide a specific vocabulary to do so
>> without dragging the whole use/mention, bnodes, named graphs issues
>> attached with RDF reification and the communities trying to resolve it.
>>
>> Any thoughts?
> 
> The relevant requirement for me is that RDFa be convertible to RDF/XML;
> i.e. no more expressive. Real quoting would involve going beyond
> the existing expressive capability of RDF/XML.

Or mapping one RDFa/HTML document to one-or-more RDF/XML-expressible
(and URI-name-able) graphs, rather than to a single flattened one?

(though I don't yet see anyone arguing for that, either).

Dan
Received on Tuesday, 17 October 2006 00:01:07 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 8 January 2008 14:15:02 GMT