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 Crunch first, background after -

The (very incomplete) generator XSLT, 
<a href="http://dannyayers.com/code/grddl/rng2grddl">rng2grddl.xsl</a>,
takes as its input a RelaxNG schema like 
<a href="http://www.relaxng.org/">this</a> from MusicBrainz, plus
an XSLT, 
<a href="http://dannyayers.com/code/grddl/config">config.xsl</a>,
which defines a few simple attribute/value pairs for the mapping.
The generated XSLT takes MB instance data like 
<a href="http://dannyayers.com/code/grddl/mb-sample">this</a> (plus
the config.xsl again), as it stands I've got as far as this
output:

 <rdf:RDF
 xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
 <mo:Artist xmlns:mo="http://purl.org/ontology/mo/"
 rdf:about="http://purl.org/ontology/mo/individuals/c0b2500e-0cef-4130-869d-732b23ed9df5"/>
 </rdf:RDF>

It's crude, doesn't really take deep structure into account, but
most mappings I've seen having been more or less 1:1 between a
given XML term and the RDF term, with a bit of syntax rearranging
for striping etc.
There are tools such as 
<a href="http://www.thaiopensource.com/relaxng/trang.html">Trang</a>
which can generate a RelaxNG schema given some instance XML, so I
think there's potential here for quite a bit of work-saving.
This morning I was greeted by a mail on the 
<a href="http://groups.google.com/group/music-ontology-specification-group/browse_thread/thread/2521ba50ff96d941/c33f9981deb5909a#c33f9981deb5909a">Music
Ontology Specification Group list</a> from danbri referring to the
MusicBrainz folk's decision to move to a non-RDF XML schema. I had
heard about that before, I won't comment except to say I think
they've likely got their cost/benefit predictions wrong - but time
will tell. Anyhow, although the choice will make integration with
other data and extensibility trickier within the context of
MusicBrainz itself, from the Semantic Web's point of view it isn't
a big deal. The post LazyWeb-requested a GRDDL transform to turn MB
XML into some RDF representation based on the draft music ontology.
With that the data can be transparently RDF, irrespective of the
syntax choice.
Now I've got loads of half-finished, domain-specific xyz2rdf
transformations. They're usually relatively straightforward to
write, although very time-consuming (hence the 
half-finished). Half the problem is enumerating and
building template outlines for all the elements. In the past I've
used Relaxer to provide a head start, it can generate an identity
transformation based on a RelaxNG schema. Except it don't seem to
work no more.
So I decided to see how difficult it would be to write a utility
to take an RelaxNG schema and create a first approximation of an
XSLT geared towards RDF/XML output for GRDDL. I've not tried
generating XSLT with XSLT before, but Bob DuCharme has done some
nice 
<a href="http://www.xml.com/lpt/a/1615">coverage</a> at xml.com. I
ran into quite a few snags, but basically got this far - 
see above.
As usual, I'd be very grateful if someone could take this of my
hands and finish it...
 
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