[commit: base] ghc-generics: Add Representable0 instances to Either and Maybe. (9d3a29e)

[José Pedro Magalhães]

Repository : ssh://darcs.haskell.org//srv/darcs/packages/base

On branch  : ghc-generics

http://hackage.haskell.org/trac/ghc/changeset/9d3a29e4b8feff1387fc26d3d6431356e1c74d51

>---------------------------------------------------------------

commit 9d3a29e4b8feff1387fc26d3d6431356e1c74d51
Author: Jose Pedro Magalhaes <jpm at cs.uu.nl>
Date:   Wed May 4 11:18:46 2011 +0200

    Add Representable0 instances to Either and Maybe.

>---------------------------------------------------------------

 Data/Either.hs |    6 ++++--
 Data/Maybe.hs  |    5 +++--
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/Data/Either.hs b/Data/Either.hs
index b45609b..0c72f97 100644
--- a/Data/Either.hs
+++ b/Data/Either.hs
@@ -1,6 +1,6 @@
 {-# LANGUAGE CPP, NoImplicitPrelude #-}
 #ifdef __GLASGOW_HASKELL__
-{-# LANGUAGE DeriveDataTypeable, StandaloneDeriving #-}
+{-# LANGUAGE DeriveDataTypeable, DeriveRepresentable, StandaloneDeriving #-}
 #endif
 
 -----------------------------------------------------------------------------
@@ -34,6 +34,7 @@ import GHC.Read
 #endif
 
 import Data.Typeable
+import GHC.Generics (Representable0)
 
 #ifdef __GLASGOW_HASKELL__
 {-
@@ -51,7 +52,8 @@ either correct or an error; by convention, the 'Left' constructor is
 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@;
diff --git a/Data/Maybe.hs b/Data/Maybe.hs
index b96efa7..e6039f2 100644
--- a/Data/Maybe.hs
+++ b/Data/Maybe.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE CPP, NoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude, DeriveRepresentable #-}
 
 -----------------------------------------------------------------------------
 -- |
@@ -33,6 +33,7 @@ module Data.Maybe
 
 #ifdef __GLASGOW_HASKELL__
 import GHC.Base
+import GHC.Generics (Representable0)
 #endif
 
 #ifdef __NHC__
@@ -65,7 +66,7 @@ import Maybe
 -- 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