Mukul Gandhi wrote:
> But I feel, that mentioning XSD as a validation technology for XML
> documents, in the XML spec is perhaps a good idea since DTD is also
> mentioned in the XML spec (which is also a XML validation technology).
> I feel, doing so doesn't promote any pedagogic or marketing attitudes
> towards XSD.
It's history. Leaving aside the question of how damaging W3C XML Schema
has been, it simply wasn't part of the original XML vision.
The three parts were supposed to be markup, style, and linking, learning
from SGML, DSSSL, and HyTime respectively. Markup, inheriting from the
SGML vision, included DTDs.
I suspect that counting validation as a fourth component might have
eased some problems all around, but that wasn't clear at the outset.
That kind of change seems like a project for XML 2.0, not for an edition
change.
(And, of course, I'd argue hard against any effort to incorporate W3C
XML Schema explicitly into XML 2.0....)
--
Simon St.Laurent
http://simonstl.com/
