Fix #3534: No need to flush the byte buffer when setting binary mode

[ghc-base.git] / GHC / Base.lhs

diff --git a/GHC/Base.lhs b/GHC/Base.lhs
index 3806d78..62612b0 100644 (file)
--- a/GHC/Base.lhs
+++ b/GHC/Base.lhs
@@ -101,7 +101,9 @@ import GHC.Classes
 import GHC.Generics
 import GHC.Ordering
 import GHC.Prim
+import {-# SOURCE #-} GHC.Show
 import {-# SOURCE #-} GHC.Err
+import {-# SOURCE #-} GHC.IO (failIO)
 
 -- These two are not strictly speaking required by this module, but they are
 -- implicit dependencies whenever () or tuples are mentioned, so adding them
@@ -111,6 +113,7 @@ import GHC.Unit ()
 
 infixr 9  .
 infixr 5  ++
+infixl 4  <$
 infixl 1  >>, >>=
 infixr 0  $
 
@@ -174,6 +177,12 @@ defined in the "Prelude" satisfy these laws.
 class  Functor f  where
     fmap        :: (a -> b) -> f a -> f b
 
+    -- | Replace all locations in the input with the same value.
+    -- The default definition is @'fmap' . 'const'@, but this may be
+    -- overridden with a more efficient version.
+    (<$)        :: a -> f b -> f a
+    (<$)        =  fmap . const
+
 {- | The 'Monad' class defines the basic operations over a /monad/,
 a concept from a branch of mathematics known as /category theory/.
 From the perspective of a Haskell programmer, however, it is best to
@@ -535,8 +544,10 @@ instance Ord Char where
 
 -- | The 'Prelude.toEnum' method restricted to the type 'Data.Char.Char'.
 chr :: Int -> Char
-chr (I# i#) | int2Word# i# `leWord#` int2Word# 0x10FFFF# = C# (chr# i#)
-            | otherwise                                  = error "Prelude.chr: bad argument"
+chr i@(I# i#)
+ | int2Word# i# `leWord#` int2Word# 0x10FFFF# = C# (chr# i#)
+ | otherwise
+    = error ("Prelude.chr: bad argument: " ++ showSignedInt (I# 9#) i "")
 
 unsafeChr :: Int -> Char
 unsafeChr (I# i#) = C# (chr# i#)
@@ -707,6 +718,38 @@ asTypeOf                =  const
 
 %*********************************************************
 %*                                                      *
+\subsection{@Functor@ and @Monad@ instances for @IO@}
+%*                                                      *
+%*********************************************************
+
+\begin{code}
+instance  Functor IO where
+   fmap f x = x >>= (return . f)
+
+instance  Monad IO  where
+    {-# INLINE return #-}
+    {-# INLINE (>>)   #-}
+    {-# INLINE (>>=)  #-}
+    m >> k    = m >>= \ _ -> k
+    return    = returnIO
+    (>>=)     = bindIO
+    fail s    = GHC.IO.failIO s
+
+returnIO :: a -> IO a
+returnIO x = IO $ \ s -> (# s, x #)
+
+bindIO :: IO a -> (a -> IO b) -> IO b
+bindIO (IO m) k = IO $ \ s -> case m s of (# new_s, a #) -> unIO (k a) new_s
+
+thenIO :: IO a -> IO b -> IO b
+thenIO (IO m) k = IO $ \ s -> case m s of (# new_s, _ #) -> unIO k new_s
+
+unIO :: IO a -> (State# RealWorld -> (# State# RealWorld, a #))
+unIO (IO a) = a
+\end{code}
+
+%*********************************************************
+%*                                                      *
 \subsection{@getTag@}
 %*                                                      *
 %*********************************************************