- From: Manu Sporny <msporny@digitalbazaar.com>
- Date: Thu, 04 Oct 2007 13:46:22 -0400
- To: RDFa <public-rdf-in-xhtml-tf@w3.org>
SWD Issue Tracker wrote: > ISSUE-61: namespace for non-prefixed values of @rel > > We've been dancing around the following for a while: > PROPOSAL - "RDFa parsers should ignore non-prefixed values of @rel that > are not part o the reserved words." > > See telecon discussion record of 2007-10-04 > http://www.w3.org/2007/10/04-rdfa-minutes.html This issue raised quite a bit of discussion on the telecon this morning and I wanted to make sure to follow it up with what seemed to be a resolution and the deeper discussion that it created about @property and generating triples. I think we all agreed that non-prefixed values in @rel and @rev should not place triples into the default graph. The only exception to this rule is that values defined in http://www.w3.org/1999/xhtml/vocab#, such as 'prev' and 'next', do generate triples and place them into the default graph. Discussion then followed to how explicit we should be when stating this in the Syntax document. There seemed to be a general consensus that the language was already in the document: http://www.w3.org/MarkUp/2007/ED-rdfa-syntax-20070921/#processorconf However, Mark was concerned that this was slightly different and had more to do with CURIEs than processor conformance, and needed to be stated explicitly, rather than implicitly. Ben was concerned that we would be repeating ourselves if we put it into the document. Mark was asked to draft some language to see where and how it would fit in. This raised another issue, however, which was: Do we apply the same triple generation rules to @property that we have defined for @rel and @rev (no prefix = no triples generated), or do we special-case @rel and @rev and any value in @property generates a triple. For example, should this generate a triple if 'foo' is not defined: <div about="#muse-knights-of-cydonia" instanceof="hmedia:Recording"> <span property="dc:title">Knights of Cydonia</span> <span property="singer">Matthew Bellamy</span> </div> We know that the following triples are generated: <#muse-knights-of-cydonia> rdf:type hmedia:Recording ; dc:title "Knights of Cydonia" ; The question is, should the following triple also be generated and placed in the default graph: <#muse-knights-of-cydonia> singer "Matthew Bellamy"; I would argue that the "singer" triple does not need to be generated for an RDFa conformant parser for the following reasons: - In the interest of RDFa adoption, the rules that we create should be orthogonal. The same CURIE processing rules that apply to @rel and @rev should be used for @property. Every special case we create will cause more confusion for publishers and RDFa adopters. - From a philosophical standpoint, singer actually doesn't mean anything because it is undefined. I don't think that the basic RDFa parsing rules should generate triples for things that do not have a defined meaning. - There is nothing preventing a RDFa conformant parser from generating the triple anyway, but according to the RDFa Syntax document Conformance section, it must place it in a graph that is not the default graph. -- manu -- Manu Sporny President/CEO - Digital Bazaar, Inc. blog: Bitmunk Launches World's First Open Music Recommendation Service http://blog.digitalbazaar.com/2007/09/09/bitmunk-music-recommendation/
Received on Thursday, 4 October 2007 17:47:22 UTC