More than three namespaces for XHTML? (was Re: What XHTML should do with namespaces)

Rick Jelliffe ricko at
Thu Sep 16 21:20:16 BST 1999

From: Shane P. McCarron <shane at>

 >Regardless, the modularization architecture of XHTML is designed to
>address the goal of extensibility on a massive scale.  It can be mapped
>into XML Schema or XML DTDs. It can rely upon XML namespaces or not.  I
>suggest you all check these documents out before worrying about the
>extensibility of XHTML

I had. Whether XHTML modularization and profiles rely on namespaces
(which surely they should) is not the issue here.  The issue is that the
XHTML namespaces should not be equated with the HTML DTDs.

Actually, it is an issue: if namespaces are to be taken from DTD, then
every different possible combination of modularized HTML has its own
effective DTD and will therefore need its own namespace.

So we are not talking about 3 namespaces for XHTML, but potentially

I have been trying to figure out what on earth the HTML WG is thinking.
The best I can come up with is that they do not think that HTML
processors will use the namespace prefixes: they will key off the local
name only and they expect that qualified names will never be used,
because the namespace declaration on the html element will preclude it.
In other words, there is some kind of tacet assumption that qualified
names are never used and that, because then CSS will work fine, there is
really no problem.  So it would not be an issue if there were 1,000
namespaces, because the namespace just selects the DTD variant. However,
view is not correct: XHTML will be used by namespace-aware applications
and these applications should not need be programmed to cope with every
namespace variant, especially if there may be dozens.

Rick Jelliffe

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