Re: [xslt] XSLT patterns without transformations?

[Daniel Veillard <veillard redhat com>]

On Tue, Feb 15, 2005 at 09:49:27AM +0100, Magnus Lie Hetland wrote:
> Daniel Veillard <veillard redhat com>:
> >
> [snip]
> >   it's really not expected to be used on its own.
> 
> Ok.
> 
> [snip]
> >   What I can support is the streaming subset in libxml/pattern.h or
> > the full XPath queries from libxml/xpath.h those are really intended to
> > be public APIs. 
> 
> I see.
> 
> Just two more questions, then (about these latter modules):
> 
>   - Is the exact XPath subset used in libxml/pattern.h documented
>     anywhere (other than in the form of source code)? As far as I can
>     see, it's a superset of the XML Schema node selector format?

  No it's a work in progress, what is in the 2.6.17 differs from
what is in CVS, which itself differs from what is in my checkout,
I will likely grow it over time

>   - Is there any (semi-)efficient way of using libxml/xpath.h in a
>     manner similar to that of XSLT patterns (i.e. checking for
>     applicability to a given node all the way up the ancestor chain),
>     or would I simply have do a number of separate checks, one for
>     each ancestor?

  Well if I wrote pattern.c for libxslt and later migrated this to
libxml2 it's really because they work differently and their cost/benefit
are really different. Except taking a precompiled form of xpath.c
expressions and trying to interpret it in a different way. Currently
there is no code which seems to satify your needs, statement which
itself is hard to assert as you didn't specify them. And pattern.[ch]
in libxml2 is a work in progress which may or may not suit your needs
in a distant future, but again since you didn't specify what you want...

Daniel

-- 
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veillard redhat com  | libxml GNOME XML XSLT toolkit  http://xmlsoft.org/
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