Re: Beyond schema

[Francis Norton <francis@redrice.com>]

Hi Philippe,

Looks like a classic case  for Schematron
(http://www.ascc.net/xml/resource/schematron/schematron.html) - this is
pretty simple to use if you understand XPath or XSLT, and allows you to
write precisely the kind of context-sensitive validation you describe. 

The external look-ups could be handled by validating against XSLT
expressions which use the document() function to load XML from some URL,
so you could have the values in an XML file or as the result of some
HTTP query, maybe against an XML-enabled database (are there any other
kind nowadays?)

Francis.

Philippe.Peeters@smals-mvm.be wrote:
> 
> Hi there,