- From: Pat Hayes <phayes@ai.uwf.edu>
- Date: Sun, 14 Oct 2001 17:42:05 -0500
- To: Frank Manola <fmanola@mitre.org>
- Cc: w3c-rdfcore-wg@w3.org
>Pat Hayes wrote: > >>...... >> >>>A clearer explanation of how our resolution affected the questions >>>that were originally raised would explicitly address the existence >>>of the locally-generated names we talk about (at least in >>>Ntriples), and would go something like this: >>> >>>"This resolves specific questions in the original issue raised thus: >>> >>>[1.] Should anonymous resources have URI's? >>> -- No (point 1 above). However, they are assigned local names, >>>of the form '_:name'. These names are not URIs, and their scope >>>is the N-triples document in which they appear. >> >> >>Er... be careful. Those are names for NODES, not for the resources >>that the nodes refer to in the RDF semantics. We really should be >>careful not to say anything that could be read as saying that these >>'_:name' thingies are names of anything in the RDF semantic domain. >>They are entirely to do with the Ntriples-to-graph mapping, which >>is a mapping between two different syntaxes. By the time one gets >>to talking about resources (the ones that the RDF graph is talking >>about) those bNode names are completely gone. An unlabeled node >>really has NO label. (Which is why it makes perfect sense that they >>should not be URIs, by the way.) > > >Point taken. How about this? > >[1.] Should anonymous resources have URI's? > -- No (point 1 above). However, in order to refer to bNodes in >N-triples, the bNodes are assigned local names, of the form >'_:name' (point 2 above). These names are not URIs, and their scope >is the N-triples document in which they appear. > >It also might be worthwhile, in order to nail this point down, to >change point 2 from starting "To reflect un-named descriptions in >N-triples" to "To refer to bNodes in N-triples". I'm happy with both of these. > > >> >>>[2.] If so, should they be clearly distinguishable as parser >>>generated URI's? >>> -- Stricly speaking, the parser is not required to generate URIs. >>>The parser *is* required to generate local names (that are not >>>URIs) for anonymous resources. These names *are* distinguishable >>>from URIs. >> >> >>What exactly is 'the parser' here? (Parser of what?) If the parser >>is parsing an Ntriples document, then the bNode ids are in the >>document already and nothing needs to be generated. If the parser >>is dealing directly with the graph syntax, then there is no need >>for the bNode labels at all, and nothing needs to be generated. If >>the parser is reading RDF/XML and constructing a graph, no new >>names need to be generated. The only case that requires generating >>any new names is when something is reading either a graph or >>RDF/XML, and *generating* an N-triples document. In that case, and >>that case alone, it needs to generate some bNode names (since the >>Ntriples syntax requires them and they aren't present in any other >>version of RDF.) But that is an issue with Ntriples, not >>(centrally) with RDF itself, and I think we should keep those >>issues separate. Our remit, after all, is to clarify RDF; >>N-triples is only a handy notation we have invented for describing >>RDF graphs, right? The graph is central. >> > > >Graham's point 1 starts off talking about "Resources that are >described but not >named in an XML serialization", so I had assumed that the parser in >question was >an XML parser. Also, as you say, any "parser" reading a graph and generating >N-triples would also need to generate bNode names. I think one of the things >we need to keep in mind in constructing this (and some other) text >is that people who had issues with the M&S don't necessarily have >this "graph is >central" point of view that we've adopted; they may very well think >(encouraged by various statements in previous writings about RDF) >that the XML syntax is what's central, and the graph is just an >expository mechanism. We're going to have to make sure we get the >"graph is central" idea across. > Right, but that is a more global effort; and in the meantime, lets just make sure we always say 'XML parser' or whatever. I honestly was not sure what you meant here, hence the screed. Pat -- --------------------------------------------------------------------- IHMC (850)434 8903 home 40 South Alcaniz St. (850)202 4416 office Pensacola, FL 32501 (850)202 4440 fax phayes@ai.uwf.edu http://www.coginst.uwf.edu/~phayes
Received on Sunday, 14 October 2001 18:42:26 UTC