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Re: RDFCore WG minutes for the Telecon 2002-07-12

From: Graham Klyne <Graham.Klyne@MIMEsweeper.com>
Date: Tue, 23 Jul 2002 20:45:23 +0100
Message-Id: <5.1.0.14.2.20020723201807.039385f0@127.0.0.1>
To: Dave Beckett <cmdjb@hoth.ilrt.bris.ac.uk>
Cc: w3c-rdfcore-wg@w3.org

At 05:35 PM 7/23/02 +0100, Dave Beckett wrote:
> >>>Graham Klyne said:
> > At 09:42 PM 7/16/02 +0100, Dave Beckett wrote:
> > >Move 6.4 into syntax - DaveB: already there, not needed.
> >
> > I'd like to push back a little on this decision.
> >
> > First, I note that the text concerned doesn't repeat material in the 
> syntax
> > draft, but refers to that material.  The reason I feel the text should 
> stay
> > here is because the syntax document (reasonably) places very heavy 
> emphasis
> > on the process of parsing RDF, and may be inaccessible to readers who are
> > not concerned with parsing issues, yet this point may be of some 
> concern to
> > them.  The text concerned is quite short:
>
>The syntax doc does have sections for introducing the syntax which is
>*not* related to parsing.  It takes a graph and explains how the
>RDF/XML for it is built, and will cover more of the detail of the XML
>syntax.  That isn't for parser writers but for explaining how the XML
>syntax works, and all the little corners.
>
>Furthermore, the later section from turning a graph to RDF/XML, also
>sometimes called serialising the graph, is also not for parser writers.

What you say is, of course, quite true.  But it remains my perception that 
this document is overwhelmingly concerned with detailing the minutiae of 
mapping between XML syntax and the abstract graph syntax.

As you say, it explains how the syntax works, including all the little 
corners.  Yes, there is other information here, but that's not clear from 
cursory glance at the document.  For example, I just went to the online 
copy of this document to try and work out where the QName to URI 
correspondence was described, and it took me about 5 minutes to find 
it.  The table of contents didn't help me on this point, and if I didn't 
know if was here somewhere I might have failed to find it.

> > [[
> > 4.3 Forming a URI reference from a Qname
> >
> > The RDF/XML syntax uses QName syntax [XML-NS] to identify various
> > resources, notably RDF properties. But the RDF graph syntax contains only
> > URI references, and does not recognize QName forms.
> >
> > Mostly, the handling of QNames is a matter for RDF parsers. But there are
> > some occasions where an RDF writer needs to know the correspondence 
> between
> > QNames and URI references (e.g. when using a typed node production). The
> > mapping is described in [RDF-SYNTAX], sections 3.1.2 or 3.1.4.
> > ]]
>
>That says both too little and too much.
>
>It doesn't explain what an RDF parser is, or what an RDF writer is.
>Neither of those is mentioned in the syntax doc either - we only talk
>about the graph and the rdf/xml document[infoset].   This sounds like
>RDF processing which we have avoided doing.

OK - that can be easily fixed.

>What are QName forms?  I prefer 'XML qnames" [citing reference in XML].

OK - that can be easily fixed.

>The subject of the section is "Forming a URI reference from a Qname"
>but the words doesn't explain how this is done, so why is it here?
>Either you should add this detail, and remove it from the syntax
>document, or remove this section.

You use the term "should" here without explaining your criteria, so I 
cannot really agree or disagree with what you say.

I'm coming to this with the view that we should be making it as easy as 
possible for developers (programmers, software designers and information 
designers) to find the information they need.  I think that a key reason 
for RDF not being especially successful to date, and I do find a continuing 
reason for resistance to adopting RDF rather than roll-your-own XML, is 
that smart people just don't get it.  If we want RDF to really succeed, 
part of our job is to make it easy for people to get it when they look at 
the specs.  The kind of audience I'm thinking of here are experienced 
system architects who will make key decisions about system design choices, 
without necessarily delving into all the details of the specifications.  I 
say all this to explain the kind of criteria I am applying, and why in my 
opinion it is important to call out certain key features of RDF.

In this case, I think the relationship between XML Qnames and URIs is such 
an important feature.  The relationship is described in the syntax 
document, but I found it was not easy to find.  So I feel it is appropriate 
to call out the issue and provide a precise reference to where the detail 
is defined.  Maybe there are other ways of achieving this goal - for 
example, I'd say a heading in the syntax document table of contents 
containing the word Qname might do it.

>I think such XML syntax issues (graph to/from RDF/XML), and XML
>qnames are best handled where the rest of the XML issues are
>explained, in the RDF/XML syntax document.  These can then be linked
>to the syntax grammar, examples and the appropriate test cases.

Well, in a sense I agree with you, which is why I didn't try and duplicate 
the material.

But... (see above).

#g


-------------------
Graham Klyne
<GK@NineByNine.org>
Received on Tuesday, 23 July 2002 16:01:40 EDT

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