begin Michael Snoyman quotation:
http://hackage.haskell.org/packages/archive/base/4.2.0.1/doc/html/Control-Mo...
file:///usr/share/doc/ghc6-doc/html/libraries/base-4.2.0.0/Control-Monad.htm...Strangely, Hayoo didn't turn this one up... anyone know why?
Hoogle finds it. I didn't think Hayoo was expected to do this sort of abstract type signature search: http://haskell.org/hoogle/?hoogle=Monad+m+%3D%3E+%28a+-%3E+a+-%3E+a%29+-%3E+... It comes up as the second hit on that search or the first hit on this one: http://haskell.org/hoogle/?hoogle=Monad+m+%3D%3E+%28a+-%3E+b+-%3E+c%29+-%3E+... That second search also shows zipWith in there; I never really thought about zipWith being like liftM2 for the list Monad. I don't believe that's actually true for the normal list Monad, but it should be true of an alternate list Monad along the lines of the Functor and Applicative instances for the ZipList newtype in Control.Applicative. -md