Aha, nice! I have wondered about doing something similar before. As part of a module on XML for my MSc I decided to go maximum overkill, and created in XSLT a

Aha, nice! I have wondered about doing something similar before. As part of a module on XML for my MSc I decided to go maximum overkill, and created in XSLT a simple key-value lookup, a breadth-first node search algorithm, and a simple TAP-based test suite to make sure it all worked properly. Almost looked at seeing how much of the Functional Data Structures book I could cram into XSLT for my dissertation before choosing something a little less ambitious.