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   Re: [xml-dev] Schema Namespace name, schemaLocation, and Schema V ersi

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> I am of the opinion that if the namespace name does not change, then
> the semantics of an XML-based markup language  should not change
> either. 

Take a look at the namespace spec.
Namespaces are not about semantics they are about names.

A language version is usually undersood to share some named constructs
with other versions of the same language. If it doesn't then it is not a
new version, it is a new language.

> Designing languages for the W3C is not like working on a college
> homework assignment where you can plead with your favorite
> professor/teaching assistant/etc to allow you to fix your mistakes
> after the fact or let you slide just once. The W3C's decisions affect
> thousands of developers and millions of computer users
> worldwide. Unfortunately it seems like the members of its working
> groups have completely lost site of this fact and act like they are
> designing research projects and prototypes which can be continually
> tweaked until they get it just right regardless of the impact of this
> haphazardness on consumers of these standards.  

I'm not sure if you meant that to be insulting, or if it just came over
that way by accident.

Keeping namespaces stable has many benefits.

Consider XSLT for example  an XSLT processor needs to know straight away
what elements are XSLT and which are foreign. Because all future
versions of XSLT are in the same namespace, it can do this, and have
specified behaviour about what to do if it discovers a (presumably new)
construct in a newer version of the language. If new versions of XSLT
were in different namespaces it would be impossible to specify this
forward compatible behaviour and newer XSLT namespaces would just look
like literal result elements. This would be a lot less useful.

The cannonical argument in the 3 namespaces for html was as follows
The point of namespaces is that you can mix elements from different
namespaces. If in your private document type you want to use html
linking semantics, you just want to go <html:a href=...  It should be
possible for any relevant processor to know the xhtml namespace, so know
that this is xhtml linking. It doesn't really matter that the content
model of some elements changes or some new elements get added between
XHTML n and XHTML n+1. If the "language is still XHTML" should by
synonymous with "the language uses the same namespace".

Changing namespaces changes the name of every construct and so _breaks_
every tool that uses the language. It's because doing that to "millions
of computer users" isn't helpful that I query your desire to change
namespaces as often as possible.



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