Re: [relax-ng] RDF spec from W3C uses RELAX NG

[James Clark <jjc@jclark.com>]

> See "RDF/XML Syntax Specification (Revised)" at:
>
> http://www.w3.org/TR/rdf-syntax-grammar/
>
> This spec contains a schema in RELAX NG (to be precise, in James' syntax),
> but does not contain a W3C XML Schema schema.

There appears to be one thing RDF needs that RELAX NG cannot currently
support.  They need to have a name class that matches all names with a
particular namespace URI whose local names start with the character "_".

This is a pretty dodgy feature and I would be reluctant to add it to RELAX
NG, but I have been wondering whether it would be possible to support this
whilst preserving closure and a relatively easy algorithm for determing
whether the intersection of two name classes are empty.

James