Jeni's Musings

I just tried this, and the big problem is that RDFa uses namespace declarations to interpret CURIEs. There’s no possible way for the XHTML+RDFa DTD to contain attribute declarations for every single possible namespace you might want to refer to from RDFa, so users either have to create a specialised DTD for their particular application, including the relevant namespace declarations, or add an ATTLIST at the top of every HTML page.

As I’ve argued before CURIEs really shouldn’t be reusing XML namespaces anyway, because they use namespaces in a completely different way from XML. It’d be far better for RDFa to extend the <base> element to cover providing the base URIs for CURIEs. That would solve the undeclared-namespace-attributes-in-DTD problem too.