Re: forest grammar/tree regular expression for RDF

Jonathan Borden wrote:
> 
> I hope the RDFCore WG will consider the forest grammar/tree regular
> expression as a specification of the formal RDF XML syntax. The unordered
> nature of RDF is best described as a forest grammar and this presents
> difficulties for traditional XML schema languages such as DTDs.
> 
snip
> 
> An advantage of specifying the grammar in this language is that it has a
> good formal semantics which is based on the formal semantics of XDuce.
> http://www.cis.upenn.edu/~hahosoya/xduce/ . Note that the XML Schema
> formalism in http://www.w3.org/TR/xmlschema-formal appears to be based on
> XDuce as well which is referenced.

This is an interesting notation.  I'd note that, unfortunately, the
example of inference rules in Section 3.8 in
http://www.w3.org/TR/xmlschema-formal seems to be in error (the
conclusion below the line should also cite g2). This illustrates the
important principle that the right formalism doesn't guarantee you'll
write the rules properly!

-- 
Frank Manola                   The MITRE Corporation
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Received on Thursday, 28 June 2001 15:38:15 UTC