RE: Namespaces, schemas, Simon's filters.

[Tim Bray <tbray@textuality.com>]

At 12:38 PM 29/08/01 -0700, John Evdemon wrote:
>> Suppose I believe that the way to accomplish this mapping is via 
>> the labels themselves  (I don't; I think decorating the instance with >
>definition-pointer attributes - from a different namespace, natch - > is the
>way to go).
>> 
>Whoa.  I've been following this thread with interest until this rather
>casual statement blew me away.  Can you do us all a favor and expand a bit
>upon this belief?

Oh, Matthew was lamenting the fact that mapping from an element
to its definition can be expensive given context-sensitive rules.
He wants to fix this by applying namespace machinery.  I don't 
like that approach, and suggested a few emails back that if you
want to ensure that you only have to do heavyweight schema 
lookup once, you decorate each node with a pointer to the 
applicable schema rule.

Personally I only use DTDs and schemas at authoring and language
design time, and the schema lookup is not a bottleneck, so I don't 
worry about the problem and wouldn't do this in any case. -Tim