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Re: Review of Reference (syntax reference? no)

From: Jeff Heflin <heflin@cse.lehigh.edu>
Date: Fri, 03 Jan 2003 10:36:38 -0500
Message-ID: <3E15AE06.FA36B843@cse.lehigh.edu>
To: Dan Connolly <connolly@w3.org>
CC: WebOnt <www-webont-wg@w3.org>

If we rely on RDF/XML being the syntax, then at the very least we need
to indicate which of the language "elements" are RDF properties and
which are RDF classes, currently everything in Reference is called an
element. We would also need, at a bare minimum, to give the domain and
range for each property. One particular glaring ommission from the
document is that it does not define which elements need
parseType="Collection." For example, look at the Boolean combination of
class expressions section. There is not even a hint that you need to use
parseType="Collection" with intersectionOf and unionOf. The only way you
could guess this is if you look at the schema, determine that it takes a
List, and then use your RDF Guru knowledge to know that
parseType="Collection" is used as shorthand notation with Lists. 

However, that said, I think doing all of this would be more confusing
than just simply laying out a grammar for the most commonly used OWL
forms. I would think we want to make it as easy as possible for people
to jump in and start using OWL. Many people may be turned off by the
fact that they to read through RDF Core's 5 documents before they can
even begin to understand OWL's 5 documents. Furthermore, don't OWL Lite
and OWL DL have syntactic restrictions not present in RDF? If so, we
must make these explicit and not just simply say look at RDF for the
syntax.

Jeff

Dan Connolly wrote:
> 
> On Thu, 2003-01-02 at 16:27, Jeff Heflin wrote:
> [...]
> > Major comments:
> > ------------------
> [...]
> > - In general the document does not serve its purpose as a syntax
> > reference very well. Ideally, I'd like to see the grammar for each
> > language construct. The RDF Schema is only helpful to those who already
> > know RDF pretty well. I'd like our potential readers to be able to use
> > this as a definitive document about what's valid syntax in the language
> > and what is not.
> 
> I don't think it's a syntax reference. The syntax is
> RDF/XML syntax. It's a vocabulary reference.
> 
> It should read like the standard C library reference,
> not like the C language reference.
> 
> (In fact, I think calling OWL a language is misleading,
> but I guess it's a little late to re-open that one.)
> 
> My major comment about the reference document is just
> to the contrary: it shouldn't be written in
> terms of XML elements and attributes at all, but
> rather in terms of properties, classes, and the
> like, ala RDFS.
> 
> The guide serves as our repository of
> copy-and-paste-able examples.
> 
> There are lots of specs for XML formats
> that just re-iterate a grammar in prose, but
> never actually tell you the meaning of the
> comination of syntactic elements. Let's
> please don't go there.
> 
> --
> Dan Connolly, W3C http://www.w3.org/People/Connolly/
Received on Friday, 3 January 2003 10:36:54 GMT

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