Underflow is a very fast implementation of McCarthy's amb operator for clojure. It has:
- a trampolining monad 'harness' that prevents stack overflow
- an evil, stateful, fast version of the same harness that is interface-compatible
- various macros for various
amboperations using the harness
Underflow is not yet ready for prime time. Use with extreme caution.
Underflow began life as an implementation of Paul Graham's continuation-passing macros for Clojure, described in On Lisp. This is combined with the observation that continuation-passing is a monad (and in fact a final in the category of monads).