    {-# OPTIONS_GHC -#include "HsBase.h" #-}
    -----------------------------------------------------------------------------
    -- |
    -- Module      :  Data.Array.IO.Internal
    -- Copyright   :  (c) The University of Glasgow 2001
    -- License     :  BSD-style (see the file libraries/base/LICENSE)
    --
    -- Maintainer  :  libraries@haskell.org
    -- Stability   :  experimental
    -- 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

    import Data.Array.MArray
    import Data.Int
    import Data.Word
    import Data.Typeable

    #ifdef __HUGS__
    import Hugs.IOArray
    #endif

    import Control.Monad.ST		( RealWorld, stToIO )
    import Foreign.Ptr		( Ptr, FunPtr )
    import Foreign.StablePtr	( StablePtr )
    import Data.Array.Base

    #ifdef __GLASGOW_HASKELL__
    import GHC.IOBase
    import GHC.Base
    #endif /* __GLASGOW_HASKELL__ */

    #include "Typeable.h"

    INSTANCE_TYPEABLE2(IOArray,iOArrayTc,"IOArray")

    -----------------------------------------------------------------------------
    -- | Instance declarations for 'IOArray's

    instance MArray IOArray e IO where
    #if defined(__HUGS__)
        getBounds   = return . boundsIOArray
        getNumElements = return . getNumElementsIOArray
    #elif defined(__GLASGOW_HASKELL__)
        {-# INLINE getBounds #-}
        getBounds (IOArray marr) = stToIO $ getBounds marr
        {-# INLINE getNumElements #-}
        getNumElements (IOArray marr) = stToIO $ getNumElements marr
    #endif
        newArray    = newIOArray
        unsafeRead  = unsafeReadIOArray
        unsafeWrite = unsafeWriteIOArray

    -----------------------------------------------------------------------------
    -- 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')
    --
    --  * @e@: the element type of the array.  Only certain element types
    --    are supported: see "Data.Array.MArray" for a list of instances.
    --
    newtype IOUArray i e = IOUArray (STUArray RealWorld i e)

    INSTANCE_TYPEABLE2(IOUArray,iOUArrayTc,"IOUArray")

    instance Eq (IOUArray i e) where
        IOUArray s1 == IOUArray s2  =  s1 == s2

    instance MArray IOUArray Bool IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Char IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Int IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Word IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray (Ptr a) IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray (FunPtr a) IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Float IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Double IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray (StablePtr a) IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Int8 IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Int16 IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Int32 IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Int64 IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Word8 IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Word16 IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Word32 IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    instance MArray IOUArray Word64 IO where
        {-# INLINE getBounds #-}
        getBounds (IOUArray arr) = stToIO $ getBounds arr
        {-# INLINE getNumElements #-}
        getNumElements (IOUArray arr) = stToIO $ getNumElements arr
        {-# INLINE newArray #-}
        newArray lu init = stToIO $ do
            marr <- newArray lu init; return (IOUArray marr)
        {-# INLINE unsafeNewArray_ #-}
        unsafeNewArray_ lu = stToIO $ do
            marr <- unsafeNewArray_ lu; return (IOUArray marr)
        {-# INLINE newArray_ #-}
        newArray_ = unsafeNewArray_
        {-# INLINE unsafeRead #-}
        unsafeRead (IOUArray marr) i = stToIO (unsafeRead marr i)
        {-# INLINE unsafeWrite #-}
        unsafeWrite (IOUArray marr) i e = stToIO (unsafeWrite marr i e)

    -- | 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')