The XML Recursion Language, XRL, is a declarative language that supports the modular composition of structured XML documents.
XRL is a very powerful "linked-data" language runtime that supports:
XRL may be used for regular XHTML web applications or for dynamic composition of arbitrary XML resources.
This tutorial provides a step-by-step guide which starts with address space mapping, introduces basic templating, examines push and pull widget design patterns, and ends with a demonstration of XRL as the foundation for an AJAX-style application.
All of the examples developed in this tutorial are available as source code in the directory [ install ]/modules/urn.org.netkernel.tutorial.xrl-x.x.x/ - where "install" is the directory in which you installed NetKernel.
The best way to learn XRL is to play around so feel free to adapt and experiment with the code.
A fast-track to XRL and a reference guide for the syntax is provided here.