xml-dev - XSet -> RDF Schema via XSLT, EBNF Groves, Bonsai and more...

[Jonathan Borden <jborden@mediaone.net>]

I have placed a short working description of XSet: the XML EBNF property set
at

http://www.openhealth.org/XSet

this contains links to goodies like an XSLT which transforms XSet into an
RDF Schema and the (still very buggy) beginnings of an XSLT which (will
hopefully :-)) transform XSet into an ISO Property Set.

On the topic of using XSLT to transform RDF<->Infoset, Dan Conolly has
posted links to a couple of nice XSLTs at:

 http://lists.w3.org/Archives/Public/www-rdf-interest/2000Aug/0061.html

Eric van der Vlist and I have been having an offline discussion about the
similarities between his technique of using a special SAX parser to "expand"
entity declarations into "Common XML" content. The advantage of this
approach is that XPath and XSLT can be used to process the resultant
abstract document (which in his example preserves the entity reference).

This is very similar to the approach of XSet which logically "expands" an
XML document into a full-fidelity grove. I have posted an example of an XSet
"expansion" of Eric's sample document:

http://www.openhealth.org/XSet/ericvdvexample.xml

and the XSet expansion:

http://www.openhealth.org/XSet/ericvdvxset.xml

Note: this is not a full "grove" because I have pruned constant string and
whitespace (S) nodes.

Eric has written an XT  output handler to "compress" a resultant transformed
tree back into its XML format. We have discussed that this handler as well
as his parser (which is derived from Aelfred2) could serve as the basis for
a full-fidelity XSet processor. A goal is to provide an XSet "bonsai" or
pruning, twisting and compression document which directs the processor as to
what level of detail to provide. For example: should it generate "element"
events alone, or add STag, ETag and EmptyElementTag events.

XMTP http://www.openhealth.org/documents/xmtp.htm is an XSet expansion of a
MIME document. In the same way that an XSet expansion of an XML document can
be produced by a modified SAX parser, an XMTP expansion of a MIME message
can be produced by a MIME parser which emits SAX events.

This technique provides a general mechanism for XPath/XPointer addressing
of, and XSLT transformation of arbitrary syntaxes expressable in EBNF. This
is the essence of the grove paradigm.

Jonathan Borden
The Open Healthcare Group
http://www.openhealth.org