+{-# LANGUAGE CPP #-}
+
-----------------------------------------------------------------------------
-- |
-- Module : Control.Monad.ST
module Control.Monad.ST
(
- -- * The 'ST' Monad
- ST, -- abstract, instance of Functor, Monad, Typeable.
- runST, -- :: (forall s. ST s a) -> a
- fixST, -- :: (a -> ST s a) -> ST s a
-
- -- * Converting 'ST' to 'IO'
- RealWorld, -- abstract
- stToIO, -- :: ST RealWorld a -> IO a
-
- -- * Unsafe operations
- unsafeInterleaveST, -- :: ST s a -> ST s a
- unsafeIOToST -- :: IO a -> ST s a
- ) where
+ -- * The 'ST' Monad
+ ST, -- abstract, instance of Functor, Monad, Typeable.
+ runST, -- :: (forall s. ST s a) -> a
+ fixST, -- :: (a -> ST s a) -> ST s a
-import Prelude
+ -- * Converting 'ST' to 'IO'
+ RealWorld, -- abstract
+ stToIO, -- :: ST RealWorld a -> IO a
+ -- * Unsafe operations
+ unsafeInterleaveST, -- :: ST s a -> ST s a
+ unsafeIOToST, -- :: IO a -> ST s a
+ unsafeSTToIO -- :: ST s a -> IO a
+ ) where
+
+#if defined(__GLASGOW_HASKELL__)
+import Control.Monad.Fix ()
+#else
import Control.Monad.Fix
+#endif
#include "Typeable.h"
-#ifdef __HUGS__
+#if defined(__GLASGOW_HASKELL__)
+import GHC.ST ( ST, runST, fixST, unsafeInterleaveST )
+import GHC.Base ( RealWorld )
+import GHC.IO ( stToIO, unsafeIOToST, unsafeSTToIO )
+#elif defined(__HUGS__)
import Data.Typeable
import Hugs.ST
import qualified Hugs.LazyST as LazyST
+#endif
+#if defined(__HUGS__)
INSTANCE_TYPEABLE2(ST,sTTc,"ST")
INSTANCE_TYPEABLE0(RealWorld,realWorldTc,"RealWorld")
LazyST.lazyToStrictST . LazyST.unsafeInterleaveST . LazyST.strictToLazyST
#endif
-#ifdef __GLASGOW_HASKELL__
-import GHC.ST ( ST, runST, fixST, unsafeInterleaveST )
-import GHC.Base ( RealWorld )
-import GHC.IOBase ( stToIO, unsafeIOToST )
-#endif
-
+#if !defined(__GLASGOW_HASKELL__)
instance MonadFix (ST s) where
- mfix = fixST
+ mfix = fixST
+#endif