php - xslt 1 and sum function

Question

I create an invoice management system using xml and PHP but the latest PHP version does not support XSLT 2.0 - therefore I have to look for an sum() alternative. How can I transform the valid xslt 2 function "sum(unitprice * quantity)" to xslt 1.0 ?

The XML stuff is based on John's Examples

I tried it with a node-set, but it is not supported "xmlXPathCompOpEval: function node-set not found in"

Answer 1

Actually, sum(price*quantity) isn't valid XSLT 2.0 syntax. I guess you mean something like `sum(for $x in * return $x/price*$x/quantity).

Summing over a computed value in XSLT 1.0 can be done in the following ways:

• two pass solution, create a node-set in which the nodes hold the computed values, then sum over the node-set

• recursive solution: write a recursive template that passes the total so far as a parameter, adds sum*quantity for the current node, then recurses to process the remaining nodes

• higher-order solution: use Dimitre Novatchev's FXSL library

• extension solution: use extension functions like saxon:sum()