Went to sweden again for a couple of days, this time to Buden. This time I learned about Finite State Machines from Skip Montanaro's fsm.py. It's pretty nifty stuff. So far I've figured out I need to generate FSMs to match the tree. I keep wavering on whether I should go ahead and implement the tree matching language. Sometimes I think it's easier than it looks, sometimes harder. I'm not really sure.