RE: [xsl] Namespace wildcards

DOM allows you to create many data structures which cannot be serialized as
well-formed XML, and which (therefore) cannot be easily mapped to the XPath
data model. If we start defining how an XPath processor should handle
anything that might be encountered in a DOM, we have got a very difficult
task on our hands. I think the course we have adopted, of mapping XPath
semantics to the InfoSet, is a sound one, and we shouldn't depart from it.

Mike Kay

> -----Original Message-----
> From: Jonas Sicking [mailto:sicking@bigfoot.com]
> Sent: 11 February 2002 16:34
> To: www-xpath-comments@w3.org
> Cc: David Carlisle
> Subject: Re: [xsl] Namespace wildcards
> 
> 
> David Carlisle wrote:
> > > Note
> > > that *[namespace-uri() = ""] strictly speaking also 
> selects the nodes in
> the
> > > "" namespace, which is different from the null namespace.
> >
> > No, the Namespace Rec explictly rules out namespaces with 
> namespace URI
> > "" which is why Xpath can unambiguously use "" to denote 
> elements in no
> > namespace.
> 
> However using DOM it is possible to create elements in the "" 
> (separate from
> null) namespace [1]. So an XPath implementation using a DOM, 
> rather then a
> raw XML file, will have to take this into account.
> 
> / Jonas Sicking
> 
> [1]
> http://www.w3.org/TR/DOM-Level-2-Core/core.html#Namespaces-Con
siderations
"Note that because the DOM does no lexical checking, the empty string will
be treated as a real namespace URI in DOM Level 2 methods. Applications must
use the value null as the namespaceURI parameter for methods if they wish to
have no namespace."

Received on Monday, 18 February 2002 06:58:04 UTC