Re: [xml-bindings]Perl Bindings

[Daniel Veillard <veillard redhat com>]

On Tue, Jan 14, 2003 at 12:48:00PM +0000, roger day globalgraphics com wrote:
> Hi,
> 
> Has anyone implemented the xsltRegisterExtModuleElement function in Perl or
> Python?

  I worked on xsltRegisterExtModuleFunction yesterday, but didn't touched
the Element stuff...
    http://bugzilla.gnome.org/show_bug.cgi?id=101602

> It certainly hasn't for Perl. Is anyone going to do this because I have
> a need to use it. I hope I'm not stepping on anyone's toes by volunteering to
> extend the interface for elements. If it's OK for me to go ahead, I was

  For python please check first the code in CVS, for Perl you should
check with AXKit/XML::LibXSLT maintainers, Matt seems to follow the
main libxslt list.

> wondering if anyone might be able to clarify a few (dumb) questions for me:
> 
> 1. The binding uses xsltRegisterExtModuleFunction instead of
> xsltRegisterExtFunction. What is the difference btn the
> module functions and the "simpler" functions?

  Hum,  the module have the capacity to run specific code at stylesheet
and/or transformation startup and end. But in the existing current bindings
that was not significant (and was broken in practice anyway).
  
> 2. The signature for xsltRegisterExtModuleElement  looks like this:
> 
> int         xsltRegisterExtModuleElement    (const xmlChar *name,
>                                              const xmlChar *URI,
>                                              xsltPreComputeFunction precomp,
>                                              xsltTransformFunction transform);
> 
> Whats a PreCompute function? I could find it defined on the website?

   the xsltPreComputeFunction is called at stylesheet compilation time.
Once compiled the stylesheet must not be modified by running transformations
and a lot of things are better done at that step than on each executions.
   The compilation process is described at
     http://xmlsoft.org/XSLT/internals.html#XSLT1

> Is it
> another registered function? Could I use the generic function that's already in
> XS file?

  You probably want to be able to register specific functions for those.
This will probably not be a trivial task...

> The last argument - the transform - is presumably the one I want to do my work
> with...could I create a function with the xsltTransformFunction signature and
> pass that?

  Yes you will have to. And then register the associated python/perl callback
associated to the class . It's not trivial, have a look at python/libxslt.c

> BTW, the XML::libXSLT module is now in CPAN.

  Matt must be happy :-)

Daniel

-- 
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