RE: SAX2 ... missing features?

[Michael Brennan <Michael_Brennan@allegis.com>]

> From: David Brownell [mailto:david-b@pacbell.net]

<snip/>

> Sounds again like a request for a SAX2-based library for XML Schema
> support.  I think that'd likely be useful; who's working on 
> one?  I can't
> believe that there isn't one in the works somewhere ... :)

Seeing PSVI info would be quite useful. I'd prefer not to see something that
is tightly coupled with a particular schema dialect, though -- even one that
has the blessing of the W3C. That's why I proposed the RDDL-inspired
interface I mentioned in an earlier post for locating schemas.

I'd prefer a more generalized SAX property/feature for enabling schema
validation, as well. Perhaps a SAX property who's value can be set to the
XML namespace of the schema dialect to use. Of course, it would be even
better to see validators implemented as SAX filters, so the programmer can
exercise more control. The only one I've seen implemented this way is James
Clark's RELAX NG validator, though I haven't attempted an exhaustive survey.

I'd be interested in hearing how other folks are dealing with this. Am I the
only one who is uncomfortable relying upon the "schemaLocation" attribute on
the root element? What about other schema dialects? RELAX NG does not even
define an equivalent of the "schemaLocation" attribute, so some sort of more
generalized mechanism seems to me to be needed. Of course, if validators and
other schema processors supported RDDL, this would be less of an issue. Is
anyone working on that?