This library makes it easy to implement monads with tricky control flow.

This is useful for: writing web applications in a sequential style,
programming games with a uniform interface for human and AI players and easy
replay capababilities, implementing fast parser monads, designing monadic
DSLs, etc.

See the project homepage http://wiki.haskell.org/Operational for a more
detailed introduction and features.

Homepage:
http://hackage.haskell.org/package/operational
