STMonadTrans-0.3.3/0000755000000000000000000000000012501510721012212 5ustar0000000000000000STMonadTrans-0.3.3/Setup.hs0000644000000000000000000000012712501510721013646 0ustar0000000000000000module Main (main) where import Distribution.Simple main :: IO () main = defaultMain STMonadTrans-0.3.3/LICENSE0000644000000000000000000000666212501510721013231 0ustar0000000000000000This library contains code from several sources. The full text of these licenses is reproduced below. All of the licenses are BSD-style or compatible. ----------------------------------------------------------------------------- Copyright Josef Svenningsson, 2008-2010 Copyright The University of Glasgow, 1994-2000 All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of Josef Svenningsson nor the names of other contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. ----------------------------------------------------------------------------- The Glasgow Haskell Compiler License Copyright 2004, The University Court of the University of Glasgow. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: - Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. - Neither name of the University nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY COURT OF THE UNIVERSITY OF GLASGOW AND THE CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE UNIVERSITY COURT OF THE UNIVERSITY OF GLASGOW OR THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. STMonadTrans-0.3.3/STMonadTrans.cabal0000644000000000000000000000232612501510721015516 0ustar0000000000000000name: STMonadTrans version: 0.3.3 cabal-version: >= 1.6 license: BSD3 license-file: LICENSE author: Josef Svenningsson maintainer: josef.svenningsson@gmail.com category: Monads build-type: Simple synopsis: A monad transformer version of the ST monad description: A monad transformer version of the ST monad Warning! This monad transformer should not be used with monads that can contain multiple answers, like the list monad. The reason is that the state token will be duplicated across the different answers and this causes Bad Things to happen (such as loss of referential transparency). Safe monads include the monads State, Reader, Writer, Maybe and combinations of their corresponding monad transformers. source-repository head type: git location: https://github.com/josefs/STMonadTrans flag splitBase description: Choose the new smaller, split-up base package. library if flag(splitBase) build-depends: base >= 3, base < 5, mtl, array else build-depends: base < 3 exposed-modules: Control.Monad.ST.Trans, Control.Monad.ST.Trans.Internal extensions: CPP, MagicHash, UnboxedTuples, Rank2Types, FlexibleInstances, MultiParamTypeClasses, UndecidableInstances STMonadTrans-0.3.3/Control/0000755000000000000000000000000012501510721013632 5ustar0000000000000000STMonadTrans-0.3.3/Control/Monad/0000755000000000000000000000000012501510721014670 5ustar0000000000000000STMonadTrans-0.3.3/Control/Monad/ST/0000755000000000000000000000000012501510721015216 5ustar0000000000000000STMonadTrans-0.3.3/Control/Monad/ST/Trans.hs0000644000000000000000000002160212501510721016642 0ustar0000000000000000{-# LANGUAGE CPP, MagicHash, UnboxedTuples, Rank2Types, FlexibleInstances, MultiParamTypeClasses, UndecidableInstances, RecursiveDo #-} {- | Module : Control.Monad.ST.Trans Copyright : Josef Svenningsson 2008-2010 (c) The University of Glasgow, 1994-2000 License : BSD Maintainer : josef.svenningsson@gmail.com Stability : experimental Portability : non-portable (GHC Extensions) This library provides a monad transformer version of the ST monad. Warning! This monad transformer should not be used with monads that can contain multiple answers, like the list monad. The reason is that the will be duplicated across the different answers and this cause Bad Things to happen (such as loss of referential transparency). Safe monads include the monads State, Reader, Writer, Maybe and combinations of their corresponding monad transformers. -} module Control.Monad.ST.Trans( -- * The ST Monad Transformer STT, runST, -- * Mutable references STRef, newSTRef, readSTRef, writeSTRef, -- * Mutable arrays STArray, newSTArray, readSTArray, writeSTArray, boundsSTArray, numElementsSTArray, freezeSTArray, thawSTArray, runSTArray, -- * Unsafe Operations unsafeIOToSTT, unsafeSTToIO, unsafeSTRefToIORef, unsafeIORefToSTRef )where import GHC.Base import GHC.Arr (Ix(..), safeRangeSize, safeIndex, Array(..), arrEleBottom) import Control.Monad.ST.Trans.Internal import Control.Monad.Fix import Control.Monad.Trans import Control.Monad.Error.Class import Control.Monad.Reader.Class import Control.Monad.State.Class import Control.Monad.Writer.Class import Control.Applicative import Data.IORef import Unsafe.Coerce import System.IO.Unsafe #if __GLASGOW_HASKELL__ < 708 isTrue# :: Bool -> Bool isTrue# x = x #endif instance Monad m => Monad (STT s m) where return a = STT $ \st -> return (STTRet st a) STT m >>= k = STT $ \st -> do ret <- m st case ret of STTRet new_st a -> unSTT (k a) new_st fail msg = lift (fail msg) instance MonadTrans (STT s) where lift m = STT $ \st -> do a <- m return (STTRet st a) liftSTT :: STT s m a -> State# s -> m (STTRet s a) liftSTT (STT m) s = m s instance (MonadFix m) => MonadFix (STT s m) where mfix k = STT $ \ s -> mdo ans@(STTRet _ r) <- liftSTT (k r) s return ans instance Functor (STTRet s) where fmap f (STTRet s a) = STTRet s (f a) instance Functor m => Functor (STT s m) where fmap f (STT g) = STT $ \s# -> (fmap . fmap) f (g s#) instance (Monad m, Functor m) => Applicative (STT s m) where pure a = STT $ \s# -> return (STTRet s# a) (STT m) <*> (STT n) = STT $ \s1 -> do (STTRet s2 f) <- m s1 (STTRet s3 x) <- n s2 return (STTRet s3 (f x)) -- | Mutable references data STRef s a = STRef (MutVar# s a) -- | Create a new reference newSTRef :: Monad m => a -> STT s m (STRef s a) newSTRef init = STT $ \st1 -> case newMutVar# init st1 of (# st2, var #) -> return (STTRet st2 (STRef var)) -- | Reads the value of a reference readSTRef :: Monad m => STRef s a -> STT s m a readSTRef (STRef var) = STT $ \st1 -> case readMutVar# var st1 of (# st2, a #) -> return (STTRet st2 a) -- | Modifies the value of a reference writeSTRef :: Monad m => STRef s a -> a -> STT s m () writeSTRef (STRef var) a = STT $ \st1 -> case writeMutVar# var a st1 of st2 -> return (STTRet st2 ()) instance Eq (STRef s a) where STRef v1 == STRef v2 = isTrue# (sameMutVar# v1 v2) -- | Executes a computation in the 'STT' monad transformer runST :: Monad m => (forall s. STT s m a) -> m a runST m = let (STT f) = m -- the parenthesis is needed because of a bug in GHC's parser in do (STTRet st a) <- ( f realWorld# ) return a -- Instances of other monad classes instance MonadError e m => MonadError e (STT s m) where throwError e = lift (throwError e) catchError (STT m) f = STT $ \st -> catchError (m st) (\e -> unSTT (f e) st) instance MonadReader r m => MonadReader r (STT s m) where ask = lift ask local f (STT m) = STT $ \st -> local f (m st) instance MonadState s m => MonadState s (STT s' m) where get = lift get put s = lift (put s) instance MonadWriter w m => MonadWriter w (STT s m) where tell w = lift (tell w) listen (STT m)= STT $ \st1 -> do (STTRet st2 a, w) <- listen (m st1) return (STTRet st2 (a,w)) pass (STT m) = STT $ \st1 -> pass (do (STTRet st2 (a,f)) <- m st1 return (STTRet st2 a, f)) -- Mutable arrays. See the definition in GHC.Arr -- | Mutable arrays data STArray s i e = STArray !i !i !Int (MutableArray# s e) instance Eq (STArray s i e) where STArray _ _ _ arr1# == STArray _ _ _ arr2# = isTrue# (sameMutableArray# arr1# arr2#) -- | Creates a new mutable array newSTArray :: (Ix i, Monad m) => (i,i) -> e -> STT s m (STArray s i e) newSTArray (l,u) init = STT $ \s1# -> case safeRangeSize (l,u) of { n@(I# n#) -> case newArray# n# init s1# of { (# s2#, marr# #) -> return (STTRet s2# (STArray l u n marr#)) }} -- | Returns the lowest and highest indices of the array boundsSTArray :: STArray s i e -> (i,i) boundsSTArray (STArray l u _ _) = (l,u) -- | Returns the number of elements in the array numElementsSTArray :: STArray s i e -> Int numElementsSTArray (STArray _ _ n _) = n -- | Retrieves an element from the array readSTArray :: (Ix i, Monad m) => STArray s i e -> i -> STT s m e readSTArray marr@(STArray l u n _) i = unsafeReadSTArray marr (safeIndex (l,u) n i) unsafeReadSTArray :: (Ix i, Monad m) => STArray s i e -> Int -> STT s m e unsafeReadSTArray (STArray _ _ _ marr#) (I# i#) = STT $ \s1# -> case readArray# marr# i# s1# of (# s2#, e #) -> return (STTRet s2# e) -- | Modifies an element in the array writeSTArray :: (Ix i, Monad m) => STArray s i e -> i -> e -> STT s m () writeSTArray marr@(STArray l u n _) i e = unsafeWriteSTArray marr (safeIndex (l,u) n i) e unsafeWriteSTArray :: (Ix i, Monad m) => STArray s i e -> Int -> e -> STT s m () unsafeWriteSTArray (STArray _ _ _ marr#) (I# i#) e = STT $ \s1# -> case writeArray# marr# i# e s1# of s2# -> return (STTRet s2# ()) -- | Copy a mutable array and turn it into an immutable array freezeSTArray :: (Ix i,Monad m) => STArray s i e -> STT s m (Array i e) freezeSTArray (STArray l u n@(I# n#) marr#) = STT $ \s1# -> case newArray# n# arrEleBottom s1# of { (# s2#, marr'# #) -> let copy i# s3# | isTrue# (i# ==# n#) = s3# | otherwise = case readArray# marr# i# s3# of { (# s4#, e #) -> case writeArray# marr'# i# e s4# of { s5# -> copy (i# +# 1#) s5# }} in case copy 0# s2# of { s3# -> case unsafeFreezeArray# marr'# s3# of { (# s4#, arr# #) -> return (STTRet s4# (Array l u n arr# )) }}} unsafeFreezeSTArray :: (Ix i, Monad m) => STArray s i e -> STT s m (Array i e) unsafeFreezeSTArray (STArray l u n marr#) = STT $ \s1# -> case unsafeFreezeArray# marr# s1# of { (# s2#, arr# #) -> return (STTRet s2# (Array l u n arr# )) } -- | Copy an immutable array and turn it into a mutable array thawSTArray :: (Ix i, Monad m) => Array i e -> STT s m (STArray s i e) thawSTArray (Array l u n@(I# n#) arr#) = STT $ \s1# -> case newArray# n# arrEleBottom s1# of { (# s2#, marr# #) -> let copy i# s3# | isTrue# (i# ==# n#) = s3# | otherwise = case indexArray# arr# i# of { (# e #) -> case writeArray# marr# i# e s3# of { s4# -> copy (i# +# 1#) s4# }} in case copy 0# s2# of { s3# -> return (STTRet s3# (STArray l u n marr# )) }} unsafeThawSTArray :: (Ix i, Monad m) => Array i e -> STT s m (STArray s i e) unsafeThawSTArray (Array l u n arr#) = STT $ \s1# -> case unsafeThawArray# arr# s1# of { (# s2#, marr# #) -> return (STTRet s2# (STArray l u n marr# )) } -- | A safe way to create and work with a mutable array before returning an -- immutable array for later perusal. This function avoids copying -- the array before returning it. runSTArray :: (Ix i, Monad m) => (forall s . STT s m (STArray s i e)) -> m (Array i e) runSTArray st = runST (st >>= unsafeFreezeSTArray) {-# NOINLINE unsafeIOToSTT #-} unsafeIOToSTT :: (Monad m) => IO a -> STT s m a unsafeIOToSTT m = return $! unsafePerformIO m unsafeSTToIO :: STT s IO a -> IO a unsafeSTToIO m = runST $ unsafeCoerce m -- This should work, as STRef and IORef should have identical internal representation unsafeSTRefToIORef :: STRef s a -> IORef a unsafeSTRefToIORef ref = unsafeCoerce ref unsafeIORefToSTRef :: IORef a -> STRef s a unsafeIORefToSTRef ref = unsafeCoerce ref STMonadTrans-0.3.3/Control/Monad/ST/Trans/0000755000000000000000000000000012501510721016305 5ustar0000000000000000STMonadTrans-0.3.3/Control/Monad/ST/Trans/Internal.hs0000644000000000000000000000277212501510721020425 0ustar0000000000000000{-# LANGUAGE MagicHash, UnboxedTuples, Rank2Types, FlexibleInstances, MultiParamTypeClasses, UndecidableInstances, RecursiveDo #-} {- | Module : Control.Monad.ST.Trans Copyright : Josef Svenningsson 2008-2010 (c) The University of Glasgow, 1994-2000 License : BSD Maintainer : josef.svenningsson@gmail.com Stability : experimental Portability : non-portable (GHC Extensions) This module provides the implementation of the 'STT' type for those occasions where it's needed in order to implement new liftings through operations in other monads. Warning! This monad transformer should not be used with monads that can contain multiple answers, like the list monad. The reason is that the will be duplicated across the different answers and this cause Bad Things to happen (such as loss of referential transparency). Safe monads include the monads State, Reader, Writer, Maybe and combinations of their corresponding monad transformers. -} module Control.Monad.ST.Trans.Internal where import GHC.Base -- | 'STT' is the monad transformer providing polymorphic updateable references newtype STT s m a = STT (State# s -> m (STTRet s a)) unSTT :: STT s m a -> (State# s -> m (STTRet s a)) unSTT (STT f) = f -- | 'STTRet' is needed to encapsulate the unboxed state token that GHC passes -- around. This type is essentially a pair, but an ordinary pair is not -- not allowed to contain unboxed types. data STTRet s a = STTRet (State# s) a