On 2/21/2010 7:44 PM, David Bertoni wrote:
On 2/20/2010 1:49 PM, BPederson wrote:
Dave-
I am still struggling with the concept, most likely because I started in
Xalan-J. From my perspective, it appears the implemetations are
considerably different. The vendor product I'm using makes the
Xalan-C++
library call to do the stylesheet transformation. I unfortunately
have no
control over the application referencing the Xalan-C++ library. All
I have
control over is the XSLT, which I make the function extension call
from. In
Xalan-J, not a problem because the Xalan.jar file knows that Rhino is
available to handle my javascript and do the file read.
So correct me on this thought process for Xalan-C++:
No doubt I can create a C++ function extension to read the file but if I
can't embed it in the application referencing the Xalan-C++ library
to do
the stylesheet transformation, then I'm out of luck? Or is there a
way for
me to create this function extension as a stand-alone DLL that gets
called
when the Xalan-C++ library, called by the vendor application, comes
across
the function call in my XSLT.
Since C++ is a statically compiled language, there's no way to do the
kinds of things you can do in Java with scripting extensions.
It would be possible to extend Xalan-C++ with some sort of syntax to
describe how to load an extension function, but there's no current
facility for that. It's a bit messy, because there is no standard
cross-platform mechanism for loading and calling functions in shared
libraries.
You can write and compile an extension function into a DLL, but the
executable that initializes the Xalan-C++ library and does the
transformation would need to be modified to install your extension
function.
Dave
XSLT Version 1.0 as implemented in XALAN-C also supports the XPath
document(url) function that returns a node-set.
This allows you to have a composite document that is constructed from
multiple sources.
<xsl:for-each select="document('url-to-file.xml')">
<!-- the template content that processes the 'url-to-file.xml' node-set -->
</xsl:for-each>
You can use the document() function anywhere a node-set object is
specified. This capability requires no custom XPath extensions.
Most compliant XSLT processors implement the document() functon.
-- Steve Hathaway
