[project @ 2005-10-13 11:09:50 by ross]

[haskell-directory.git] / Data / Array / IO / Internals.hs

diff --git a/Data/Array/IO/Internals.hs b/Data/Array/IO/Internals.hs
index 689333a..8789a94 100644 (file)
--- a/Data/Array/IO/Internals.hs
+++ b/Data/Array/IO/Internals.hs
@@ -1,4 +1,4 @@
-{-# OPTIONS -#include "HsBase.h" #-}
+{-# OPTIONS_GHC -#include "HsBase.h" #-}
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Data.Array.IO.Internal
@@ -7,15 +7,17 @@
 -- 
 -- Maintainer  :  libraries@haskell.org
 -- Stability   :  experimental
--- Portability :  non-portable
+-- Portability :  non-portable (uses Data.Array.Base)
 --
 -- Mutable boxed and unboxed arrays in the IO monad.
 --
 -----------------------------------------------------------------------------
 
+-- #hide
 module Data.Array.IO.Internals (
    IOArray(..),                -- instance of: Eq, Typeable
    IOUArray(..),       -- instance of: Eq, Typeable
+   castIOUArray,       -- :: IOUArray ix a -> IO (IOUArray ix b)
  ) where
 
 import Prelude
@@ -23,30 +25,25 @@ import Prelude
 import Data.Array.MArray
 import Data.Int
 import Data.Word
-import Data.Dynamic
+import Data.Typeable
 
 #ifdef __HUGS__
 import Hugs.IOArray
-import Hugs.IOExts             ( unsafeCoerce )
-import Data.Array.Storable
 #endif
 
-#ifdef __GLASGOW_HASKELL__
+import Control.Monad.ST                ( RealWorld, stToIO )
 import Foreign.Ptr             ( Ptr, FunPtr )
 import Foreign.StablePtr       ( StablePtr )
 import Data.Array.Base
 
-import GHC.Arr                 ( STArray )
+#ifdef __GLASGOW_HASKELL__
 import GHC.IOBase
 import GHC.Base
 #endif /* __GLASGOW_HASKELL__ */
 
-iOArrayTc :: TyCon
-iOArrayTc = mkTyCon "IOArray"
+#include "Typeable.h"
 
-instance (Typeable a, Typeable b) => Typeable (IOArray a b) where
-  typeOf a = mkAppTy iOArrayTc [typeOf ((undefined :: IOArray a b -> a) a),
-                               typeOf ((undefined :: IOArray a b -> b) a)]
+INSTANCE_TYPEABLE2(IOArray,iOArrayTc,"IOArray")
 
 -----------------------------------------------------------------------------
 -- | Instance declarations for 'IOArray's
@@ -67,33 +64,20 @@ instance MArray IOArray e IO where
     unsafeRead  = unsafeReadIOArray
     unsafeWrite = unsafeWriteIOArray
 
-
-#ifdef __HUGS__
-type IOUArray = StorableArray
-#endif
-
-#ifdef __GLASGOW_HASKELL__
--- GHC only to the end of file
-
 -----------------------------------------------------------------------------
 -- Flat unboxed mutable arrays (IO monad)
 
 -- | Mutable, unboxed, strict arrays in the 'IO' monad.  The type
 -- arguments are as follows:
 --
---  * @i@: the index type of the array (should be an instance of @Ix@)
+--  * @i@: the index type of the array (should be an instance of 'Ix')
 --
 --  * @e@: the element type of the array.  Only certain element types
---    are supported: see 'MArray' for a list of instances.
+--    are supported: see "Data.Array.MArray" for a list of instances.
 --
-newtype IOUArray i e = IOUArray (STUArray RealWorld i e) deriving Eq
-
-iOUArrayTc :: TyCon
-iOUArrayTc = mkTyCon "IOUArray"
+newtype IOUArray i e = IOUArray (STUArray RealWorld i e)
 
-instance (Typeable a, Typeable b) => Typeable (IOUArray a b) where
-  typeOf a = mkAppTy iOUArrayTc [typeOf ((undefined :: IOUArray a b -> a) a),
-                                typeOf ((undefined :: IOUArray a b -> b) a)]
+INSTANCE_TYPEABLE2(IOUArray,iOUArrayTc,"IOUArray")
 
 instance HasBounds IOUArray where
     {-# INLINE bounds #-}
@@ -303,4 +287,11 @@ instance MArray IOUArray Word64 IO where
     {-# INLINE unsafeWrite #-}
     unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)
 
-#endif /* __GLASGOW_HASKELL__ */
+-- | Casts an 'IOUArray' with one element type into one with a
+-- different element type.  All the elements of the resulting array
+-- are undefined (unless you know what you\'re doing...).
+castIOUArray :: IOUArray ix a -> IO (IOUArray ix b)
+castIOUArray (IOUArray marr) = stToIO $ do
+    marr' <- castSTUArray marr
+    return (IOUArray marr')
+