xml-dev - Re: Tool X (was Re: simple question on namespaces.)

["Simon St.Laurent" <simonstl@simonstl.com>]

At 05:03 PM 12/29/00 -0500, Jonathan Borden wrote:
>Simon St.Laurent wrote:
>> Perhaps, though you left out the possibility someone mentioned here
>earlier
>> of multiple definitions for a single namespace - the three DTDs for XHTML
>> case, for instance.
>
>    Yeah but a doctypedecl is no better at linking a document to a DTD. No
>one has been screaming bloody murder about DTDs in XML 1.0 though!

Huh?  A DOCTYPE declaration has to point to one and only one of those DTDs,
while the XHTML namespace only suggests that it conforms to one of those
three.

I did try to raise a fuss about the use of URNs for DTD system literals,
but no one seemed interested.

>    The point has been raised that a namespace URI identifies a single
>schema (forget content negotiation for the moment). My point is that
>doctypedecls also identify a single schema, hence this problem is not new.
>If this argument is used to claim 'namespaces are broken' as I've heard,
>then it equally claims 'XML 1.0 is broken'. Of course nothing is perfect, so
>everything is broken.

I don't think it's at all clear that namespace URIs - unlike doctypedecls -
do appopriately point to a single schema of whatever kind.  Unless you want
to create an uber-DTD for XHTML that validates all three flavors - strict,
transitional, and frameset.

Hey - maybe we can restart the 'one or three namespaces for XHTML' debate
while we're at it.  I know everyone would just love it.

Simon St.Laurent
XML Elements of Style / XML: A Primer, 2nd Ed.
XHTML: Migrating Toward XML
http://www.simonstl.com - XML essays and books