RE: [xml-dev] The prefix "fgdc" for element "fgdc:fgdc" is not bound

[noah_mendelsohn@us.ibm.com]

Michael Kay wrote:

> I gather the decision arose from some metaphysical debate about
> the intended
> semantics of namespaces. I'm no fan of that kind of discussion:it's up 
to
> users, not specification writers, to decide what their data 
> actually means.
> Specification writers should confine themselves to describing 
> observable and
> testable behaviour.

I wasn't part of those discussions, but I think the reasoning was along 
these lines:  there was a hope that a given qualified name with a non-null 
namespace would in fact have some particular use.  So 
{http://example.org/booknamespace,title} might be the title of a book, 
regardless of the document in which it appeared; 
{http://example.org/peoplenamespace,title} might be used for titles like 
Mr., Ms., etc.  There's clearly no hope for that with unqualified names, 
since they are clearly used in all sorts of contradictory ways.  Note 
that, modulo some real messiness about the difference between QNames and 
URIs, these names are sort of grounded in the Web, so if you wanted to 
find information about {http://example.org/booknamespace,title}  you'd 
have a fighting chance of doing it by trying an HTTP GET from 
http://example.org/booknamespace. 

Ironically, and the reason I'm so aware of this, the fact that XML Schema 
allows elementForm="qualified" on locally scoped names pretty thoroughly 
undercuts this view.  FWIW, I think elementForm="qualified" is on balance 
OK.  It's what people want in many case.  Still, it means that you can 
have expanded name {http://example.org/peoplenamespace,xxx} used for 
completely different things, and with different validation rules, even in 
the same document.  Some members of the XML community were strongly 
opposed to that, and I can see why.  I happen to think that allowing it is 
the lesser of the evils.

Noah

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Noah Mendelsohn 
IBM Corporation
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Cambridge, MA 02142
1-617-693-4036
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