- From: pat hayes <phayes@ihmc.us>
- Date: Tue, 19 Aug 2003 09:24:36 -0700
- To: Frank Manola <fmanola@mitre.org>
- Cc: w3c-rdfcore-wg@w3.org
OK, how about this: In the RDF/XML syntax described in RDF/XML Syntax Specification (Revised) [RDF-SYNTAX] the use of rdf:ID creates a reification of the enclosed triple in which the reified triple is a URI constructed from the baseURI of the XML document and the value of rdf:ID as a fragID. Pat >pat hayes wrote: > >>Frank Manola wrote: > >> >>>Argh! I hope the Primer isn't misleading on this question, >>>because I don't think your last sentence is accurate. What I try >>>to say is that rdf:ID provides a way of indicating that, in >>>addition to generating the usual triple, a reification of that >>>triple with a specific URIref (generated from the rdf:ID value) is >>>to be generated as well. It doesn't (I don't think) "attach a URI >>>reference to a triple in an RDF/XML document". >> >> >>Well, isn't that attachment done by the fact of the URI appearing >>in the rdf:ID in the document in question? But OK, I could rephrase >>it thus: >> >>(In the RDF/XML syntax described in RDF/XML Syntax Specification >>(Revised) [RDF-SYNTAX] the use of rdf:Id with a URI reference as >>value creates a reification of the enclosed triple, with that URI >>reference as the reified triple.) >> >>Would that be better? Its more awkward but maybe more accurate. >> >>Pat >> > > >Pat-- > >What I'm getting at is what I say later in the Primer reification section: > >"Using rdf:ID as shown in Example 20 generates the reification >automatically, and provides a convenient way of indicating the >URIref to be used as the subject of the statements in the >reification. Moreover, it provides a partial "hook" relating the >triples in the reification with the piece of RDF/XML syntax that >caused them to be created, since the value triple12345 of the rdf:ID >attribute is used to generate the URIref of the subject of the >reification triples. However, this relationship is once again >outside RDF, since there is nothing in the resulting triples that >explicitly says that the original triple had the URIref >exproducts:triple12345 (RDF does not assume there is any >relationship between a URIref and any RDF/XML that it might have >been used or abbreviated in)." > >That is, if you look at the graph (Figure 17), there's nothing that >connects the triple described by the RDF/XML ("the enclosed triple") >to the URIref used in the reification triples (generated from the >rdf:ID attribute value). So there's sort of an "attachment" between >the generated graph and some RDF/XML, but the interpretation of that >attachment is still strictly outside of RDF. I just wouldn't want >anyone to interpret this parenthetical remark (whatever text it >contains) as an exception to or qualification of the original >statement that there isn't really a connection defined by RDF. This >would be an application-dependent convention that related (in a >specific way) the resulting graph to the RDF/XML used to generate >it; and this information wouldn't necessarily be available to a >second party receiving the graph. > >NB: "rdf:Id with a URI reference as value" isn't strictly accurate >either. rdf:ID ("ID" in caps) doesn't take a URIref as a value; >its value is used (as a fragment id) to *construct* a URIref. > >--Frank > > > >>>--Frank >>> >>>pat hayes wrote: >>> >>>> >>>>After reading Frank's Primer text, I have changed some text in >>>>the reification section 3.2.1 of Semantics from this: >>>> >>>>"Although RDF applications may use reification to refer to triple >>>>tokens in RDF documents, the connection between the document and >>>>its reification must be maintained by some means external to RDF. >>>>RDF syntax provides no means to 'connect' an RDF triple to its >>>>reification. " >>>> >>>>to this: >>>> >>>>"Although RDF applications may use reification to refer to triple >>>>tokens in RDF documents, the connection between the document and >>>>its reification must be maintained by some means external to the >>>>RDF graph syntax. (The RDF/XML syntax described in RDF/XML Syntax >>>>Specification (Revised) [RDF-SYNTAX] provides rdf:Id to attach a >>>>URI reference to a triple in an RDF/XML document, and create the >>>>corresponding reification.) " >>>> >>>>I hope the WG does not object to this; I think the rather sharp >>>>negative was misleading. >>>> >>>>Pat >>>> >>> >>> >>>-- >>>Frank Manola The MITRE Corporation >>>202 Burlington Road, MS A345 Bedford, MA 01730-1420 >>>mailto:fmanola@mitre.org voice: 781-271-8147 FAX: 781-271-875 >> >> >> > > >-- >Frank Manola The MITRE Corporation >202 Burlington Road, MS A345 Bedford, MA 01730-1420 >mailto:fmanola@mitre.org voice: 781-271-8147 FAX: 781-271-875 -- --------------------------------------------------------------------- IHMC (850)434 8903 or (650)494 3973 home 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32501 (850)291 0667 cell phayes@ihmc.us http://www.ihmc.us/users/phayes
Received on Saturday, 23 August 2003 02:42:34 UTC