[XML-SIG] Value of namespaces (was RE: [XML-SIG] IPC7 results)

Wes Rishel wes@rishel.com
Wed, 18 Nov 1998 08:12:41 -0800

> -----Original Message-----
> From: xml-sig-admin@python.org [mailto:xml-sig-admin@python.org]On
> Behalf Of Walter Underwood
> Sent: Tuesday, November 17, 1998 9:01 AM
> To: xml-sig@python.org
> Subject: Re: [XML-SIG] Value of namespaces (was RE: [XML-SIG] IPC7
> results)
> A different comment -- it sounds like you are trying to get the
> DTD to enforce the model, rather than just making something that
> can be parsed. There are lots and lots of constraints that cannot
> be expressed in a DTD (age is positive, these references form a
> tree), so enforcing the exact sub-elements of each element is
> just one more thing that can't be enforced in the DTD. Even if
> it was possible to specify what was legal, you couldn't specify
> that all elements must be there.
> Since you've got to do post-parsing checking anyway, trying to
> express too much stuff in the DTD is probably wasted effort.

We agree with you completely.

Indeed, the debate that keeps resurfacing in our discussions is whether
there is any substantial benefit to using a validating parser. At least in
our context, which includes XML and other representations of the same
content, we have to have a metamodel that essentially duplicates the content
model anyway.