- From: John McClure <jmcclure@hypergrove.com>
- Date: Wed, 15 Aug 2007 08:56:23 -0700
- To: "Owl Dev" <public-owl-dev@w3.org>
>From http://www.webont.org/owl/1.1/xml_syntax.html: <owl11xml:Declaration> <owl11xml:OWLClass owl11xml:URI="#animal"/> </owl11xml:Declaration> <owl11xml:Declaration> <owl11xml:ObjectProperty owl11xml:URI="#eats"/> </owl11xml:Declaration> The document cited above doesn't clarify any relationship of owl11xml:URI with our friends rdf:ID & rdf:about. Can anyone help on this? I am also wondering how Pat's statement that there are no 'declarations' -- that there are assertions only in RDF semantics -- squares with this XML element? Finally, how does this element relate to declaredAs? Thanks >-----Original Message----- >From: public-owl-dev-request@w3.org >[mailto:public-owl-dev-request@w3.org]On Behalf Of John McClure >Sent: Friday, August 10, 2007 12:30 PM >To: Bijan Parsia >Cc: Owl Dev >Subject: RE: declaredAs > > > >Bijan, >Some specific responses to your citation & other remarks: > >>http://www.w3.org/TR/rdf-syntax-grammar/#section-Syntax-ID-xml-base >> >>"""RDF/XML allows further abbreviating RDF URI references in XML >>attributes in two ways. >>The rdf:ID attribute on a node element (not property element, that >>has another meaning) can be used instead of rdf:about and gives a >>relative RDF URI reference equivalent to # concatenated with the >>rdf:ID attribute value. So for example if rdf:ID="name", that would >>be equivalent to rdf:about="#name". rdf:ID provides an additional >>check since the same name can only appear once in the scope of an >>xml:base value (or document, if none is given), so is useful for >>defining a set of distinct, related terms relative to the same RDF >>URI reference.""" > >The spec specifically says that rdf:ID's semantic is overloaded .... a >different >semantic in different contexts ... that's a real problem I am proposing should >be fixed. The second-to-last statement does NOT say that ID & about are >semantically equivalent; it says their subjects are pointing at the same >resource. Finally, the last sentence is clear to me, as it's refering to the >*functional role* of rdf:ID as an XML ID and is therefore not new information. >(I'm thinking I can't find an XML schema definition for ID because the spec >requires rdf:ID to functionally perform as an XML ID, but because it's a uri, >then it can't parse as a standard XML ID. Hmm, maybe there's a way around this >in xmls.) > >>I agree that the last sentence is misleading and there are only a >>very limited number of cases where it can be made to work and >>requires otherwise restricting the syntax. And has no effect on the >>model. > >You mean on the graph. That is where we differ, as I am saying that when the >Description is converted to a Statement then the effect of rdf:ID vs rdf:about >is clear, because the uri of an about Statement is a blank while the uri of an >ID Statement is the same as the subject's. > ><snip/> > >>> My thinking is that, to the contrary, a given document may >>> have only one declaration for a thing, but can have as many >>> assertions about it >>> as they care to have, so it's important to have both properties. >> >>In OWL 1.1 things can have many declarations per term. > >Is the functional XML ID role for rdf:ID now being eliminated? > >>I don't know why only one is valuable. > >Because declarations take precedence over assertions. A 'trust' thing. > >>But rdf:ID doesn't get you *any sort of >>declaration*. It's *just a funny way of making an assertion*. > >Nope, I don't agree -- I don't see this in the specs anywhere. > > >
Received on Wednesday, 15 August 2007 15:56:05 UTC