Re: [xml] Streaming XPath restrictions in libxml2

["James Dennett" <jdennett technocom-wireless com>]

Daniel Veillard [veillard redhat com] wrote:
> On Wed, Oct 25, 2006 at 02:57:47PM +0530, Ravi Reddy wrote:
> > Hi,
> >
> > I have a set of questions regarding the level of streaming XPath
> > support. Please answer them.
> >
> > 1). Is there any documentation on what subset of XPath 1.0 does
libxml2
> > support in streaming mode?
>
>   No. Basically the one needed for XSD support.
>
> > 2). Does libxml2 internally construct DOM for streamable XPath
> > evaluation?
>
>   no

Good ;)

> > 3). Does libxml2 support only forward looking XPath and if so what
> > subset?
>
>   of course only forward. Again subset needed for XSD. See the XSD
spec.
> It was mostly designed as an internal feature, the driver was that
spec.

It's such a useful feature that it would be valuable if an interface
specification could be written, though even if someone (<hides/>) steps
up to do that then we might need to recognize that this could be more
volatile than the interfaces which are implementations of mainstream
standards.

-- James