[commit: packages/base] master: Add `{-# MINIMAL #-}` annotations to typeclasses (7ab6249)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/base

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/7ab62490dbc1ea7430fe60d5dad9c3b0fa0bedad/base

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

commit 7ab62490dbc1ea7430fe60d5dad9c3b0fa0bedad
Author: Herbert Valerio Riedel <hvr at gnu.org>
Date:   Wed Sep 18 10:45:38 2013 +0200

    Add `{-# MINIMAL #-}` annotations to typeclasses
    
    This makes use of the new `{-# MINIMAL #-}` facility (see #7633)
    for the following typeclasses
    
     - `Bits`
     - `Foldable`
     - `Fractional`
     - `Num`
     - `MonadZip`
     - `Read`
     - `Show`
     - `Storable`
     - `Traversable`
    
    Signed-off-by: Herbert Valerio Riedel <hvr at gnu.org>


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

7ab62490dbc1ea7430fe60d5dad9c3b0fa0bedad
 Control/Monad/Zip.hs |    1 +
 Data/Bits.hs         |    5 +++++
 Data/Foldable.hs     |    1 +
 Data/Traversable.hs  |    1 +
 Foreign/Storable.hs  |    4 ++++
 GHC/Num.lhs          |    1 +
 GHC/Read.lhs         |    1 +
 GHC/Real.lhs         |    1 +
 GHC/Show.lhs         |    1 +
 9 files changed, 16 insertions(+)

diff --git a/Control/Monad/Zip.hs b/Control/Monad/Zip.hs
index 824e373..ec13eed 100644
--- a/Control/Monad/Zip.hs
+++ b/Control/Monad/Zip.hs
@@ -47,6 +47,7 @@ class Monad m => MonadZip m where
     -- munzip is a member of the class because sometimes
     -- you can implement it more efficiently than the
     -- above default code.  See Trac #4370 comment by giorgidze
+    {-# MINIMAL mzip | mzipWith #-}
 
 instance MonadZip [] where
     mzip     = zip
diff --git a/Data/Bits.hs b/Data/Bits.hs
index e2eb3fe..76af67b 100644
--- a/Data/Bits.hs
+++ b/Data/Bits.hs
@@ -239,6 +239,11 @@ class Eq a => Bits a where
         known as the population count or the Hamming weight. -}
     popCount          :: a -> Int
 
+    {-# MINIMAL (.&.), (.|.), xor, complement,
+                (shift | (shiftL, shiftR)),
+                (rotate | (rotateL, rotateR)),
+                bitSize, bitSizeMaybe, isSigned, testBit, bit, popCount #-}
+
 class Bits b => FiniteBits b where
     finiteBitSize :: b -> Int
 
diff --git a/Data/Foldable.hs b/Data/Foldable.hs
index de6c056..e61972d 100644
--- a/Data/Foldable.hs
+++ b/Data/Foldable.hs
@@ -151,6 +151,7 @@ class Foldable t where
       where
         mf Nothing y = Just y
         mf (Just x) y = Just (f x y)
+    {-# MINIMAL foldMap | foldr #-}
 
 -- instances for Prelude types
 
diff --git a/Data/Traversable.hs b/Data/Traversable.hs
index 7872a61..5fa91e8 100644
--- a/Data/Traversable.hs
+++ b/Data/Traversable.hs
@@ -164,6 +164,7 @@ class (Functor t, Foldable t) => Traversable t where
     -- and collect the results.
     sequence :: Monad m => t (m a) -> m (t a)
     sequence = mapM id
+    {-# MINIMAL traverse | sequenceA #-}
 
 -- instances for Prelude types
 
diff --git a/Foreign/Storable.hs b/Foreign/Storable.hs
index 86e65f8..7441741 100644
--- a/Foreign/Storable.hs
+++ b/Foreign/Storable.hs
@@ -149,6 +149,10 @@ class Storable a where
    peek ptr = peekElemOff ptr 0
    poke ptr = pokeElemOff ptr 0
 
+   {-# MINIMAL sizeOf, alignment,
+               (peek | peekElemOff | peekByteOff),
+               (poke | pokeElemOff | pokeByteOff) #-}
+
 -- System-dependent, but rather obvious instances
 
 instance Storable Bool where
diff --git a/GHC/Num.lhs b/GHC/Num.lhs
index 689fafc..7cfc377 100644
--- a/GHC/Num.lhs
+++ b/GHC/Num.lhs
@@ -63,6 +63,7 @@ class  Num a  where
     {-# INLINE negate #-}
     x - y               = x + negate y
     negate x            = 0 - x
+    {-# MINIMAL (+), (*), abs, signum, fromInteger, (negate | (-)) #-}
 
 -- | the same as @'flip' ('-')@.
 --
diff --git a/GHC/Read.lhs b/GHC/Read.lhs
index 05ee4f9..a8494be 100644
--- a/GHC/Read.lhs
+++ b/GHC/Read.lhs
@@ -206,6 +206,7 @@ class Read a where
   readList     = readPrec_to_S (list readPrec) 0
   readPrec     = readS_to_Prec readsPrec
   readListPrec = readS_to_Prec (\_ -> readList)
+  {-# MINIMAL readsPrec | readPrec #-}
 
 readListDefault :: Read a => ReadS [a]
 -- ^ A possible replacement definition for the 'readList' method (GHC only).
diff --git a/GHC/Real.lhs b/GHC/Real.lhs
index 1d53637..5cb79de 100644
--- a/GHC/Real.lhs
+++ b/GHC/Real.lhs
@@ -192,6 +192,7 @@ class  (Num a) => Fractional a  where
     {-# INLINE (/) #-}
     recip x             =  1 / x
     x / y               = x * recip y
+    {-# MINIMAL fromRational, (recip | (/)) #-}
 
 -- | Extracting components of fractions.
 --
diff --git a/GHC/Show.lhs b/GHC/Show.lhs
index 3f31e38..bce3e73 100644
--- a/GHC/Show.lhs
+++ b/GHC/Show.lhs
@@ -157,6 +157,7 @@ class  Show a  where
     showsPrec _ x s = show x ++ s
     show x          = shows x ""
     showList ls   s = showList__ shows ls s
+    {-# MINIMAL showsPrec | show #-}
 
 showList__ :: (a -> ShowS) ->  [a] -> ShowS
 showList__ _     []     s = "[]" ++ s