Re: [xml-dev] When to Validate XML?

[ht@cogsci.ed.ac.uk (Henry S. Thompson)]

Leigh Dodds <ldodds@ingenta.com> writes:

> > -----Original Message-----
> > From: Ajay K sanghi [mailto:sanghi@giasdl01.vsnl.net.in]
> > Sent: 01 November 2001 06:12
> > To: Max Dunn; 'Magick, Brian'; xml-dev@lists.xml.org
> > Subject: RE: [xml-dev] When to Validate XML?
> >
> > I think an important question to ask before deciding to turn on validation
> > at DTD/Schema level is "How can I report back the appropriate
> > non-conforming error in the XML file to the sender?".
> >
> > If my application has better reporting capability then I would turn off
> > DTD/Schema validation. If in conjunction, I can use DTD/Schema
> > validation as "invariant", nothing like it. And of course, if I am able to
> report
> > non-conforming error using DTD/Schema validation then I would turn it on.
> 
> This is an interesting point. Schema languages are increasingly
> powerful in terms of the validation rules that they can express, but
> are their error reporting capabilities increasing in step? One could
> argue that this isn't a function of the schema language, but of
> the processor.
> 
> However, it seems like a declarative way to associate readable text
> messages for a user, or pointers to additional documentation would be a
> useful feature. (A user here might be another application, and the pointer
> may
> be to a series of data cleansing routines).
> 
> So, do any of the existing schema languages support this?

XML Schema supports it explicitly in the REC -- every
element/attribute information item _must_ be
annotated post-validation to indicate its cool/losing/not-checked
status, and a PSVI property is specified for listing cross-references
to the REC for each error detected wrt an item.

ht
-- 
  Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
          W3C Fellow 1999--2001, part-time member of W3C Team
     2 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- (44) 131 650-4440
	    Fax: (44) 131 650-4587, e-mail: ht@cogsci.ed.ac.uk
		     URL: http://www.ltg.ed.ac.uk/~ht/