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Re: ACTION 2001-10-12#5: frankm respond to gk text

From: Pat Hayes <phayes@ai.uwf.edu>
Date: Fri, 12 Oct 2001 20:17:17 -0500
Message-Id: <p05101014b7ed41ed872d@[]>
To: Frank Manola <fmanola@mitre.org>
Cc: w3c-rdfcore-wg@w3.org
>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.)

>[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.

Pat Hayes
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Received on Friday, 12 October 2001 21:17:31 UTC

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