This repository contains several versions of the redex model, each in
it's own branch. They were rather clumsely pulled into their own branch
after the fact, mostly for reference.

The master branch contains the most recent redex model. This version is
documented. Other versions are not as well documented, but structured
similarly, so read the documentation in this one first.

There is also a Haskell model, which hasn't been worked on since perhaps
the Fall semester.