Re: [xml] XPath on a subtree

[Daniel Veillard <veillard redhat com>]

On Sat, Mar 23, 2013 at 02:10:42PM +0000, Alex Bligh wrote:
> On 23 Mar 2013, at 13:54, Daniel Veillard wrote:
>
> >  I though I had added a macro but searched for it an no it's not there.
> > In the python bindings there is an extra function called
> >
> > libxml2mod.xmlXPathSetContextNode()
>
> That was what I was thinking of, but ...
>
> > xmlXPathObjectPtr
> > xmlXPathNodeEval(xmlNodePtr node, const xmlChar *str, xmlXPathContextPtr ctx)
> >
> > as a simple wrapper around xmlXPathEval
>
> ... that would be equally useful.

  Do you mind doing a patch ? :-)

> > actually it's good to set the doc too at that point before reusing
> > the context in the loop.
> >
> >      ctxt->doc = doc;
>
> Isn't the doc set when you create the context? xmlXPathNewContext takes
> a doc ptr.

  yes but it's better to have the node and the doc in sync. Some XPath
evaluation may reset the doc (from libxslt, probably impossible in
practice from libxml2).

Daniel

-- 
Daniel Veillard      | Open Source and Standards, Red Hat
veillard redhat com  | libxml Gnome XML XSLT toolkit  http://xmlsoft.org/
http://veillard.com/ | virtualization library  http://libvirt.org/