This fails horribly in Jhc: {-# OPTIONS_NHC98 --prelude #-} ----------------------------------------------------------------------------- -- | -- Module : Control.Monad.Instances -- Copyright : (c) The University of Glasgow 2001 -- License : BSD-style (see the file libraries/base/LICENSE) -- -- Maintainer : libraries@haskell.org -- Stability : provisional -- Portability : portable -- -- 'Functor' and 'Monad' instances for @(->) r@ and -- 'Functor' instances for @(,) a@ and @'Either' a@. module Control.Monad.Instances (Functor(..),Monad(..)) where import Prelude instance Functor ((->) r) where fmap = (.) instance Monad ((->) r) where return = const f >>= k = \ r -> k (f r) r instance Functor ((,) a) where fmap f (x,y) = (x, f y) instance Functor (Either a) where fmap _ (Left x) = Left x fmap f (Right y) = Right (f y)