is there any simple way to use scripting languages such as php in a xslt
stylesheet?

It would seem that there are different mechanisms to embed
several of the leading scripting/programming languages in
several of the leading tranformation engines.  They differ
between implementations.  Certainly I know that libxslt
has interfaces to Tcl (by yours truly), Perl and Python.

These interfaces allow the scripting language to host a
tranformation, as well as allow extensions to be defined
in the stylesheet to call back into the scripting language.

Some allow script code to be embedded in the stylesheet,
but I don't think that's a good idea (see below).

all I'd like to do is to use it to get the POST data from a form and
send it to a xslt stylesheet as params to update a xml file

That's the job of a framework - the thing that handles the
incoming HTTP request and invokes the transformation.
The framework should pass the query to the stylesheet as
a parameter.  I wrote a framework, using Tcl, that constructs
a query document in memory and then passed the URI of that
document to the stylesheet.  The stylesheet simply uses the
document() function to retrieve its query document.

Note that a stylesheet may not even know that a scripting language
is involved in its invocation.

need this scripting language again to write the xml file).

In XSLT1.1 I've found a reference to xsl:script, which seems to be what
I am looking for, but I don't know any stable implementation of this
element.

I don't think xsl:script has survived (thank goodness!).
There were major objections to it.

My (much) preferred approach is to completely separate the
scripting from the stylesheet, via the XSLT extension mechanism.
This hides the implementation from the stylesheet, which is
important is software engineering.  It allows the extensions
to replaced by some other implementation, without affecting the
stylesheet 'code'.

I don't want to, either, process the xslt with this scripting language.
I'd rather the other way around.

Cheers,
Steve Ball

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