{-# LANGUAGE CPP, NoImplicitPrelude #-}
#ifdef __GLASGOW_HASKELL__
-{-# LANGUAGE DeriveDataTypeable, StandaloneDeriving #-}
+{-# LANGUAGE DeriveDataTypeable, DeriveRepresentable, StandaloneDeriving #-}
#endif
-----------------------------------------------------------------------------
#endif
import Data.Typeable
+import GHC.Generics (Representable0)
#ifdef __GLASGOW_HASKELL__
{-
used to hold an error value and the 'Right' constructor is used to
hold a correct value (mnemonic: \"right\" also means \"correct\").
-}
-data Either a b = Left a | Right b deriving (Eq, Ord, Read, Show)
+data Either a b = Left a | Right b
+ deriving (Eq, Ord, Read, Show, Representable0)
-- | Case analysis for the 'Either' type.
-- If the value is @'Left' a@, apply the first function to @a@;
-{-# LANGUAGE CPP, NoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude, DeriveRepresentable #-}
-----------------------------------------------------------------------------
-- |
#ifdef __GLASGOW_HASKELL__
import GHC.Base
+import GHC.Generics (Representable0)
#endif
#ifdef __NHC__
-- error monad can be built using the 'Data.Either.Either' type.
data Maybe a = Nothing | Just a
- deriving (Eq, Ord)
+ deriving (Eq, Ord, Representable0)
instance Functor Maybe where
fmap _ Nothing = Nothing