RE: [DM] namespace nodes

I agree with you, I think the text is wrong. There should never be a
namespace node whose string value (namespace URI) is zero-length, as
namespace nodes always represent the declaration of a namespace and not the
undeclaration.

I think that it is now possible in XSLT to create a parentless namespace
node: viz

<xsl:variable name="ns" as="node()">
  <xsl:namespace name="my">namespace.uri</xsl:namespace>
</xsl:variable>

Though this probably isn't what was envisaged when the DM spec was written -
at one time there was an idea that namespace nodes would be "shared" between
elements in some way.

Michael Kay

> -----Original Message-----
> From: Oliver Becker [mailto:obecker@informatik.hu-berlin.de] 
> Sent: 24 June 2003 17:00
> To: public-qt-comments@w3.org
> Subject: [DM] namespace nodes
> 
> 
> 
> Hello,
> 
> I would appreciate if the XQuery 1.0 and XPath 2.0 Data Model 
> defines whether a default null namespace is represented by a 
> namespace node or not.
> 
> Section 4.5 Namespaces says in 4.5.1
> 
>    2 The namespace prefix may be the empty sequence. If the 
> URI is the 
>      zero-length string, the prefix must be the empty sequence.
>      
> Hmm, there might exist namespace nodes without prefix and 
> without URI. Such a node would be created by an xmlns="". 
> OTOH, I would interpret this as an undeclaration of the 
> default namespace, 
> thus it removes an existing namespace node (that would be 
> present otherwise).
> 
> The specification should unambiguously state, under which 
> circumstances such namespace nodes come into live.
> 
> I prefer not to introduce such "null" namespace nodes. There 
> shouldn't be a 
> difference between <foo /> and <foo xmlns="" />
> 
> One more question:
> Are situations imaginable that a namespace node doesn't have 
> a parent? Since the specification thinks so I would like to 
> see a comment just as for attribute nodes.
> 
> Regards,
> Oliver Becker
> 
>      
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Received on Tuesday, 24 June 2003 12:46:24 UTC