Re: [xml-dev] XML spec and XSD

[Mukul Gandhi <gandhi.mukul@gmail.com>]

Hi Liam,

On Sun, Nov 15, 2009 at 6:19 AM, Liam Quin <liam@w3.org> wrote:
> Speaking as W3C XML Activity Lead :-) I don't see a reason to
> give XSD special status in that way.

No problems :) That's fair enough for me.

> W3C XSD has a lot of uses, and works well if you are also
> using XSLT 2, XQuery, Web Services or other specifications
> where the XSD support is well-integrated.  This doesn't in
> any way preclude using RelaxNG, DTDs, Schematron, or any
> other sort of validation, and it's not really the place of
> the XML specification to give a list of other technologies
> that are used with it or build on it.

I agree with this. I was actually not forcing a point of view, to
really specify something like XSD, RelaxNG or other XML validation
technology into the XML spec. I just find specification of a statement
like, "an XML document is valid, if it's valid according to a DTD" in
the XML spec, confusing given the existence now, of other XML
validation technologies like XSD et al.

As you have suggested below, refactoring the XML spec and separating
DTD into a separate document looks a reasonable solution to this
problem, and would dispel the confusion which user's seemingly have
when they read the terms "validation" and DTD in the most recent XML
specs.

> As Tim and others said, DTDs are in the XML specification for
> historical reasons.

I appreciate this. It's good that, something like this existed in the
early days of XML (that was a nice innovation, in the absence of
anything else, as we speak of XSD and other validation technologies,
as of today). But now, the XML validation technologies, are in a
different paradigm and I guess, the XML and related specs should
explain the relationship between XML markup and it's validation,
reflecting the current world we are living in :) IMHO, it's fine if we
rearchitect the XML specs, as you suggested to achieve this clarity
for users.

> If we had the resources, I can certainly
> imagine refactoring XML 1.0 to put DTDs into a separate document,
> and to bring into that document namespaces and xml:base and
> maybe others. But the work of doing that is much greater than
> it sounds -- making sure the text retains the same meaning,
> and even that documents referring to specific productoins in the
> EBNF grammar are not broken as a result.

I hope this can happen. Perhaps, a work to create drafts for such a
architectural breakup of XML specs, can begin :)

> So I don't expect much enthusiasm for making a new edition of
> XML to make the Informative References include XSD, but
> please don't take that as a negative statement about XSD :-)

I appreciate your speaking about this topic, and supporting few of my points :)



-- 
Regards,
Mukul Gandhi