rmonad provides a restricted monad class in the Control.RMonad hierarchy. The class makes use of associated datatypes (available in GHC 6.8), using an idea learnt from Wolfgang Jeltsch: http://www.haskell.org/pipermail/haskell-cafe/2008-March/041084.html It also provides a way to treat a restricted monad as a normal monad using a generic wrapper type. This idea is described here: http://hsenag.livejournal.com/11803.html?nc=5 See the haddock documentation for information on how to use it. darcs get http://code.haskell.org/rmonad TODO Add instances for all the mtl stuff. Consider also doing this for mtl-tf (namespacing issues?) Add all the normal monad combinators