fp2/week2/mart/StdMonad.dcl

   1 definition module StdMonad
   2
   3 class return        c :: a -> c a
   4 class (>>=) infix 0     c :: (c a) (a -> c b) -> c b
   5 class fail          c :: c a
   6
   7 class Monad             c | return, >>= c
   8 class MonadFail     c | Monad, fail c