Re: [xml] XPath relative search?

[Daniel Veillard <veillard redhat com>]

On Tue, Sep 16, 2003 at 11:25:05PM -0700, Christopher J. Grayce wrote:
> (gdb) print xp_context->node->type
> $29 = XML_ELEMENT_NODE
> (gdb) print xp_context->node->name
> $30 = (const xmlChar *) 0x8063a30 "instance"
> (gdb) next
> 132       if ((xp_nodes = xp_result->nodesetval)) {
> (gdb) print xp_context->node->type
> $31 = XML_DOCUMENT_NODE                       <---- huh??
> (gdb) print xp_context->node->name
> $32 = (const xmlChar *) 0x0                   <---- huh??
>
> --------------
>
> That is, the act of calling xmlXPathEval seems to reset the
> xmlXPathNewContext to the top of the document.  

  Bahh, register allocation, debugger and code compiled
with -O2 can lead to some surprise, I assume it's the problem,
or maybe the function resets the current evaluation node, 
that should not be a problem. xp_result should still have
the result of the query.

> How, then, does one do a relative XPath search?  I'm mystified.

  Set xp_context->node to the current node before calling the
XPath evaluation function, and use a relative search, //text
is an absolute search ! .//text is the relative version c.f.
   http://www.w3.org/TR/xpath

Daniel

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