RE: Transitive closure for XPath

> For higher order functions, some lexical construct is needed
> that prevents
> an XPath processor from evaluating the parameters passed to a function
> before evaluating the function. If you want to pass a function as a
> parameter, you will have to prevent the processor from evaluating that
> function before passing it.

Yes. Saxon's solution is to combine this with the facility to create an
expression from a string, so you write

saxon:sum($nodeset, saxon:expression("@price * @qty"))

(An expression is logically a function whose only argument is the XPath
context)

I think David Rosenborg's FXPath proposal has gone rather further than this,
towards full lambda expressions.

Mike Kay