Re: [xml-dev] GenX and attribute QNames

From
Elliotte Rusty Harold <>
To
Tim Bray <>
Date
2004-03-10T22:17:35Z
ID
<p06010210bc75431c9f57@[192.168.254.4]>
Thread
Re: [xml-dev] GenX and attribute QNames
At 12:44 PM -0800 3/10/04, Tim Bray wrote:

>Er, I thought that canonical XML required that namespace names be 
>declared only at the first point they're used.  Am I wrong?
>
>If I'm right, it's a big problem; it means you can't have a qname in 
>an attribute value unless that namespace has already been used in a 
>containing element or one of its attributes.  So I'm probably wrong.

You're wrong. :-) Namespaces are output when they first come into 
scope, not when they're first used. This is covered in section 2.3 of 
the canonical XML spec. The key thing is to remember that in the 
XPath data model on which canonical XML is based, the namespace axis 
contains all namespaces in scope on the element, not simply those 
declared or used.
-- 

   Elliotte Rusty Harold
   
   Effective XML (Addison-Wesley, 2003)
   http://www.cafeconleche.org/books/effectivexml
   http://www.amazon.com/exec/obidos/ISBN%3D0321150406/ref%3Dnosim/cafeaulaitA