Parameterizing REXML::XPath expressions

Hi there,

I’m struggling a bit with what I think should be straightforward.

I basically want to pull information out of an XML document.

The working example I have is as follows…

version = REXML::XPath.match(@doc, ‘//[@pn=“123-4567-89”]/

However, I don’t want to hardcode the value of the part number (pn).
I want to ref it via a variable.

e.g. if I have a variable ‘partnum’ which is set to “123-4567-89”

then I was expecting the expression to be something like…

version = REXML::XPath.match(@doc, ‘//[@pn=partnum]/
@version’).to_s # no match

I’ve tried some variations but with same no match result.
But basically I’m just guessing which is bad.

All of the REXML tutorials always hardcode their examples.
Any help would be appreciated.