Re: [xml] xmlXPathEval(*str,*ctxt)

[Daniel Veillard <veillard redhat com>]

On Thu, Mar 28, 2002 at 09:47:24AM -0500, Robert G. Brown wrote:
> It seems that in a document like:
> 
> <?xml version="1.0"?>
> <xmlsysd>
>   <proc>
>   </proc>
> </xmlsysd>
> 
> rgb lucifer|T:443>./testXPath -i xmlsysd.xml /xmlsysd/proc/uptime
> Object is a Node Set :
> Set contains 0 nodes:
> rgb lucifer|T:444>./testXPath -i xmlsysd.xml /xmlsysd/proc/uptime/up
> Object is a Node Set :
> NodeSet is NULL !
> rgb lucifer|T:457>./testXPath -i xmlsysd.xml /xmlsysd/proc
> Object is a Node Set :
> Set contains 1 nodes:
> 1  ELEMENT proc
> 
> In my own code the following fragment (either way -- one step or with a
> segment copied from textXPath.c) does NOT return null in the second case
> although the node obviously does not exist.  Is this not a bug?  Do I
> have to test all segments of a path to a node?

  it's not a bug. ht eobject recturned will not be null in either
case, in both case it will be flagged as a being a node set in 
the first case obj->nodeset is not NULL and is of zero len and in
the second case obj->nodeset is NULL.
  They have the same semantic.

  it simply won't allocate a node set array if not needed.

Daniel

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