Add I/O support for RDF/XML:
I have an RDF/XML parser (based on a fork of HaXML) that I'd like to integrate at some time ...
If it helps, the source code and test suite are here: http://www.ninebynine.org/Software/HaskellRDF/RDF/Harp/ or buried in the contents of http://www.ninebynine.org/Software/HaskellRDF/20040713-HaskellRDF.zip
The parser is very closely based on the XML syntax spec, and passes most of the test cases created by the working group and by Dave Beckett for his Redland toolkit.
The modified HaXml is at http://www.ninebynine.org/Software/HaskellUtils/HaXml-1.12/ or zip file http://www.ninebynine.org/Software/HaskellUtils/20040802-Haxml-1.12.zip
As I recall, the main change I needed to make was to enhance the HaXml representation of XML elements to allow additional values to be added -- mainly to support XML namespaces, which are required for RDF/XML. In the process, I think I may have weakened the monadic properties of some of the key HaXml elements. In the process, I also made several changes to make the parser more compliant with the W3C test suite. I think some but not all of my changes were folded into the primary implementation of HaXml, but I suspect not enough to be compatible with the RDF parser in its current form.