Re: Problems with xmlns parts in XPointer

At 7:33 PM -0600 6/3/01, Eve.Maler@Sun.COM wrote:

>You're right that no namespace context is "picked up" in 
>interpreting xpointer() stuff.  We had originally allowed it to be 
>picked up as a kind of shorthand, but got the comment that this 
>introduces problems with copying and pasting URI references, since 
>they're incomplete without the namespace knowledge.  Is the loss of 
>the shorthand the reason why you say that having to use xmlns() is 
>"wrong"?
>

Yes, that's the reason. It seems wrong to me that the in-scope 
namespace bindings suddenly lose their scope inside an XPointer. I'd 
be more comfortable with this if XML Schemas and XSLT hadn't already 
established that namespace bindings do apply in attribute values.

I do see your point about copying and pasting. However, the same can 
be said for elements, especially elements in the default namespace 
with no prefix, but others as well. If you copy and paste something 
that depends on namespaces into a part of the document or a different 
document with a different set of namespace bindings, then the 
namespace of the thing may change. XPointers are hardly unique. I'm 
not sure XPointers alone should attempt to address this problem. I 
think the problem is global across XML specs, and local solutions 
like xmlns() just muddy the waters. I prefer a consistent if flawed 
approach to half a dozen different better solutions.

>>  At the least, I'd like to see more explicit discussion of the meaning of
>>  xmlns attributes with respect to XPointers in the final draft, even if
>>  the semantics and syntax remain as they currently are.
>
>Do you have a suggestion for what should be added?
>

Something very clear and to the point such as "If an XPointer is 
included in an XML document, then the namespace mappings created by 
xmlns attributes in that document do not apply to namespace prefixes 
found in XPointers. The default namespace for the element in which 
the XPointer appears does not apply to element names in the XPointer 
either."

I also suggest a couple more examples in which the document does set 
up a prefix  that seems to be used in the XPointer, and yet it does 
not apply. Currently you only give positive examples of xmlns() 
parts. I'd ask for a negative example that shows the xmlns:prefix 
attribute doesn't work.
-- 

+-----------------------+------------------------+-------------------+
| Elliotte Rusty Harold | elharo@metalab.unc.edu | Writer/Programmer |
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Received on Monday, 4 June 2001 09:21:36 UTC