Managing Generation of Output Filenames

We have an HTML output script that is creating lots of output files
where the filenames we use for the generated files have to be both
meaningful and reflect some pre-defined business rules for how the names
are constructed.

The challenge we're running into is we'd like to have a single chunk of
code for generating the filenames, which have to go into both
xsl:document tags and into hrefs used to create navigation links and
authored cross references. We can't see any way to do this in XSL
without writing an extension function. 

The problem as we see it is that there's no way to generate a string
that can be used in both the <xsl:document> tag and in hrefs. If it was
only needed for elements in the output name space, it wouldn't be a
problem--just create a template that generates an xsl:attribute element
and that has all the business logic. But I don't know of a way to have
the same code also return a string that can be subsequently passed into
the xsl:document's href attribute.

Is our analysis correct or have we missed something? It's not a big
problem to write an extension function but of course I'd prefer to use
XSL-defined mechanisms if at all possible.

Thanks,

Eliot Kimber
ISOGEN International, LLC

 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list