Recursive sums in xslt 1.0

in xslt1 if you want to store an expression that is going to be
re-evaluated you need to put it in a named template. Then you could call
that so long as you replaced sum(..) with a recursive template that
iterated over the nodes calculating the sum and calling your named
templates.

The context is a financial xslt file that outputs itemised monthly
reports from an unitemised year-to-date xml file.  For each item in the
output file, I need to do two tests: one for date and the other for some
other feature (usually party [i.e. payer/payee]). This would be an
example with no parameters or variables:

<xsl:variable name="actualelectricity">
<xsl:value-of select="sum(/statement/item[date >= 20050228 and party[contains('DEML')]]/amount)"/>
</xsl:variable>

What I want to do is turn the two expressions in the test into
independent variables so that I could do something like this:

<xsl:variable name="actualelectricity"> <xsl:value-of select="sum(/statement/item[$datetest and $electricitytest]/amount)"/>
</xsl:variable>

Where

datetest = (date >= 20050228)

and

electricitytest = (party[contains('DEML')])

The reason for doing this is that it allows me to reuse the category tests (i.e. the party[contains()]-type tests) independently of the date tests: for year-to-date summaries, and for a miscellaneous class that consists of anything that is not identified by an explicit category test.

--
Daniel Paul O'Donnell, PhD
Associate Professor of English
University of Lethbridge
Lethbridge AB T1K 3M4
Tel. (403) 329-2377
Fax. (403) 382-7191
E-mail <daniel.odonnell@xxxxxxxx>
Home Page <http://people.uleth.ca/~daniel.odonnell/>
The Digital Medievalist Project: <http://www.digitalmedievalist.org/>