I've taken a pretty serious look at XQuery and I think that it fits the needs for what I wanted. Ivelin wrote a pretty nice article on it for xml.com, you might want to check it out.
+1, with a warning: XQuery is not supposed to react on an incoming data feed but to "pull" data from somewhere and work on them. This means that I don't really see how it might fit into a pipeline at a transformer level since it doesn't have the idea of a incoming data stream.
There is an implementation of XQuery that compiles the xquery template (in lack of another term) into bytecode, passing thru Kawa which is a scheme2java compiler.
Look at it here
http://www.gnu.org/software/qexo/
The concept is pretty cool, even if it doesn't touch the issues with data manipulation.
Another implementation (which also has Cocoon 1.x hooks!) is
http://kweelt.sourceforge.net/
They are both GPLed.
Not really. Qexo is actually dual licensed: as long as you don't modify it you're pretty much free to do what you want with it. I asked on community@ and had a green light from Roy in including it in the ASF CVS tree. Not that I like the idea: it seems to me that some modification is required to have it work with Cocoon, but this is where it stands.
Ciao,
-- Gianugo Rabellino Pro-netics s.r.l. http://www.pro-netics.com
