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RE: declaredAs

From: John McClure <jmcclure@hypergrove.com>
Date: Wed, 15 Aug 2007 08:56:23 -0700
To: "Owl Dev" <public-owl-dev@w3.org>
Message-ID: <MGEEIEEKKOMOLNHJAHMKEEJPEFAA.jmcclure@hypergrove.com>

>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

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