- From: Manu Sporny <msporny@digitalbazaar.com>
- Date: Thu, 18 Oct 2007 02:50:12 -0400
- To: RDFa mailing list <public-rdf-in-xhtml-tf@w3.org>
Ben Adida wrote: > Manu Sporny wrote: >> TC48: SEMANTICS OK, SPARQL OK >> I've stared at this one for quite some time and thoroughly >> confused myself. Somebody that is more familiar with the >> processing rules will have to explain why this is right or >> wrong. It passes the latest pyRDFa and SPARQL implementations. > > Here's how I think about it: > > If you had the following markup: > > <div about="http://www.example.org" > rel="foaf:knows"> > <p property="foaf:name">John Doe</p> > </div> > > Then by the chaining rule of @rel, you get: > > <http://www.example.org> foaf:knows _:x > _:x foaf:name "John Doe" . > > where the bnode _:x "corresponds" to the DIV and is the chaining node. > > @instanceof, when added, applies to this corresponding bnode, the > chaining node, so, when you add > > instanceof="foaf:Person", you get the same triples as above plus: > > _:x rdf:type foaf:Person . Ah... so you're saying that the SPARQL should be: ASK WHERE { <http://www.example.org> <http://xmlns.com/foaf/0.1/knows> _:a . _:a <http://xmlns.com/foaf/0.1/name> "John Doe" . _:a <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://xmlns.com/foaf/0.1/Person> . } So, just to clarify: If @rel is specified and @resource is specified, the @instanceof is applied to the subject set by @resource (TC47). If @rel is specified but @resource and @about is not specified, the @instanceof creates a new bnode and specifies that as the active @about for the @rel (TC48)? It seems like we're saying if you do this: <div about="http://www.example.org" instanceof="foaf:Person"> then you get this: <http://www.example.org> <rdf:type> foaf:Person but if you do this: <div about="http://www.example.org" instanceof="foaf:Person" rel="foaf:knows" resource="#foo"> then you get this: <http://www.example.org> <foaf:knows> <#foo> <#foo> <rdf:type> foaf:Person That is confusing to me. It feels like we're changing the meaning of @about/@instanceof when they are used together based on whether or not @rel and @resource exist. When we use @about and @instanceof in the same element, the same thing should always happen... @instanceof should be applied to @about. What am I missing? It feels like I'm missing something fundamental. -- 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, 18 October 2007 06:50:23 UTC