Stability	experimental
Safe Haskell	None
Language	Haskell2010

Control.Concurrent.STM.Unlift

Contents

Core
TVar
TMVar
TChan
TQueue
TBQueue
Low-level functions on file descriptors
Re-exported modules

Description

Lifted versions of functions from Control.Concurrent.STM:

This is meant to be a drop-in replacement for Control.Concurrent.STM and UnliftIO.STM, for more streamlined use of STM functions when using mtl-style monad transformer stacks.
Functions that normally return a STM result are abstracted to MonadSTM. (Some functions necessarily require the more restrictive MonadUnliftSTM typeclass due to STM results appearing in negative positions of the function signature.)
This module also includes STM-related functions which return an IO result. These are abstracted to MonadIO or MonadUnliftIO and are re-exported directly from UnliftIO.STM.

Synopsis

data STM a
atomically :: MonadIO m => STM a -> m a
retry :: MonadSTM m => m a
check :: MonadSTM m => Bool -> m ()
orElse :: MonadUnliftSTM m => m a -> m a -> m a
throwSTM :: (Exception e, MonadSTM m) => e -> m a
catchSTM :: (Exception e, MonadUnliftSTM m) => m a -> (e -> m a) -> m a
data TVar a
newTVarIO :: MonadIO m => a -> m (TVar a)
readTVarIO :: MonadIO m => TVar a -> m a
newTVar :: MonadSTM m => a -> m (TVar a)
readTVar :: MonadSTM m => TVar a -> m a
writeTVar :: MonadSTM m => TVar a -> a -> m ()
modifyTVar :: MonadSTM m => TVar a -> (a -> a) -> m ()
modifyTVar' :: MonadSTM m => TVar a -> (a -> a) -> m ()
modifyTVarM :: MonadSTM m => TVar a -> (a -> m a) -> m ()
modifyTVarM' :: MonadSTM m => TVar a -> (a -> m a) -> m ()
swapTVar :: MonadSTM m => TVar a -> a -> m a
registerDelay :: MonadIO m => Int -> m (TVar Bool)
mkWeakTVar :: MonadUnliftIO m => TVar a -> m () -> m (Weak (TVar a))
data TMVar a
newTMVar :: MonadSTM m => a -> m (TMVar a)
newEmptyTMVar :: MonadSTM m => m (TMVar a)
newTMVarIO :: MonadIO m => a -> m (TMVar a)
newEmptyTMVarIO :: MonadIO m => m (TMVar a)
takeTMVar :: MonadSTM m => TMVar a -> m a
putTMVar :: MonadSTM m => TMVar a -> a -> m ()
readTMVar :: MonadSTM m => TMVar a -> m a
tryReadTMVar :: MonadSTM m => TMVar a -> m (Maybe a)
swapTMVar :: MonadSTM m => TMVar a -> a -> m a
tryTakeTMVar :: MonadSTM m => TMVar a -> m (Maybe a)
tryPutTMVar :: MonadSTM m => TMVar a -> a -> m Bool
isEmptyTMVar :: MonadSTM m => TMVar a -> m Bool
mkWeakTMVar :: MonadUnliftIO m => TMVar a -> m () -> m (Weak (TMVar a))
data TChan a
newTChan :: MonadSTM m => m (TChan a)
newTChanIO :: MonadIO m => m (TChan a)
newBroadcastTChan :: MonadSTM m => m (TChan a)
newBroadcastTChanIO :: MonadIO m => m (TChan a)
dupTChan :: MonadSTM m => TChan a -> m (TChan a)
cloneTChan :: MonadSTM m => TChan a -> m (TChan a)
readTChan :: MonadSTM m => TChan a -> m a
tryReadTChan :: MonadSTM m => TChan a -> m (Maybe a)
peekTChan :: MonadSTM m => TChan a -> m a
tryPeekTChan :: MonadSTM m => TChan a -> m (Maybe a)
writeTChan :: MonadSTM m => TChan a -> a -> m ()
unGetTChan :: MonadSTM m => TChan a -> a -> m ()
isEmptyTChan :: MonadSTM m => TChan a -> m Bool
newTQueue :: MonadSTM m => m (TQueue a)
newTQueueIO :: MonadIO m => m (TQueue a)
readTQueue :: MonadSTM m => TQueue a -> m a
tryReadTQueue :: MonadSTM m => TQueue a -> m (Maybe a)
peekTQueue :: MonadSTM m => TQueue a -> m a
tryPeekTQueue :: MonadSTM m => TQueue a -> m (Maybe a)
writeTQueue :: MonadSTM m => TQueue a -> a -> m ()
unGetTQueue :: MonadSTM m => TQueue a -> a -> m ()
isEmptyTQueue :: MonadSTM m => TQueue a -> m Bool
newTBQueue :: MonadSTM m => Natural -> m (TBQueue a)
newTBQueueIO :: MonadIO m => Natural -> m (TBQueue a)
readTBQueue :: MonadSTM m => TBQueue a -> m a
tryReadTBQueue :: MonadSTM m => TBQueue a -> m (Maybe a)
peekTBQueue :: MonadSTM m => TBQueue a -> m a
tryPeekTBQueue :: MonadSTM m => TBQueue a -> m (Maybe a)
writeTBQueue :: MonadSTM m => TBQueue a -> a -> m ()
unGetTBQueue :: MonadSTM m => TBQueue a -> a -> m ()
isEmptyTBQueue :: MonadSTM m => TBQueue a -> m Bool
isFullTBQueue :: MonadSTM m => TBQueue a -> m Bool
threadWaitReadSTM :: (MonadIO io, MonadSTM stm) => Fd -> io (stm (), io ())
threadWaitWriteSTM :: (MonadIO io, MonadSTM stm) => Fd -> io (stm (), io ())
module Control.Monad.STM.Class
module Control.Monad.STM.Unlift
module Control.Monad.IO.Class
module Control.Monad.IO.Unlift

Core

data STM a #

A monad supporting atomic memory transactions.

Instances

Instances details

Monad STM	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods (>>=) :: STM a -> (a -> STM b) -> STM b # (>>) :: STM a -> STM b -> STM b # return :: a -> STM a #
Functor STM	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods fmap :: (a -> b) -> STM a -> STM b # (<$) :: a -> STM b -> STM a #
Applicative STM	Since: base-4.8.0.0
Instance details Defined in GHC.Conc.Sync Methods pure :: a -> STM a # (<>) :: STM (a -> b) -> STM a -> STM b # liftA2 :: (a -> b -> c) -> STM a -> STM b -> STM c # (>) :: STM a -> STM b -> STM b # (<*) :: STM a -> STM b -> STM a #
Alternative STM	Since: base-4.8.0.0
Instance details Defined in GHC.Conc.Sync Methods empty :: STM a # (<\|>) :: STM a -> STM a -> STM a # some :: STM a -> STM [a] # many :: STM a -> STM [a] #
MonadPlus STM	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods mzero :: STM a # mplus :: STM a -> STM a -> STM a #
MonadSTM STM Source #
Instance details Defined in Control.Monad.STM.Class Methods liftSTM :: STM a -> STM a Source #
MonadUnliftSTM STM Source #
Instance details Defined in Control.Monad.STM.Unlift Methods askUnliftSTM :: STM (UnliftSTM STM) Source # withRunInSTM :: ((forall a. STM a -> STM a) -> STM b) -> STM b Source #

atomically :: MonadIO m => STM a -> m a #

Lifted version of atomically

Since: unliftio-0.2.1.0

retry :: MonadSTM m => m a Source #

Lifted version of retry

check :: MonadSTM m => Bool -> m () Source #

Lifted version of check

orElse :: MonadUnliftSTM m => m a -> m a -> m a Source #

Lifted version of orElse

throwSTM :: (Exception e, MonadSTM m) => e -> m a Source #

Lifted version of throwSTM

catchSTM :: (Exception e, MonadUnliftSTM m) => m a -> (e -> m a) -> m a Source #

Lifted version of catchSTM

TVar

data TVar a #

Shared memory locations that support atomic memory transactions.

Instances

Instances details

Eq (TVar a)	Since: base-4.8.0.0
Instance details Defined in GHC.Conc.Sync Methods (==) :: TVar a -> TVar a -> Bool # (/=) :: TVar a -> TVar a -> Bool #

newTVarIO :: MonadIO m => a -> m (TVar a) #

Lifted version of newTVarIO

Since: unliftio-0.2.1.0

readTVarIO :: MonadIO m => TVar a -> m a #

Lifted version of readTVarIO

Since: unliftio-0.2.1.0

newTVar :: MonadSTM m => a -> m (TVar a) Source #

Lifted version of newTVar

readTVar :: MonadSTM m => TVar a -> m a Source #

Lifted version of readTVar

writeTVar :: MonadSTM m => TVar a -> a -> m () Source #

Lifted version of writeTVar

modifyTVar :: MonadSTM m => TVar a -> (a -> a) -> m () Source #

Lifted version of modifyTVar

modifyTVar' :: MonadSTM m => TVar a -> (a -> a) -> m () Source #

Lifted version of modifyTVar'

modifyTVarM :: MonadSTM m => TVar a -> (a -> m a) -> m () Source #

A monadic version of modifyTVar

modifyTVarM' :: MonadSTM m => TVar a -> (a -> m a) -> m () Source #

A monadic version of modifyTVar'

swapTVar :: MonadSTM m => TVar a -> a -> m a Source #

Lifted version of swapTVar

registerDelay :: MonadIO m => Int -> m (TVar Bool) #

Lifted version of registerDelay

Since: unliftio-0.2.1.0

mkWeakTVar :: MonadUnliftIO m => TVar a -> m () -> m (Weak (TVar a)) #

Lifted version of mkWeakTVar

Since: unliftio-0.2.1.0

TMVar

data TMVar a #

A TMVar is a synchronising variable, used for communication between concurrent threads. It can be thought of as a box, which may be empty or full.

Instances

Instances details

Eq (TMVar a)
Instance details Defined in Control.Concurrent.STM.TMVar Methods (==) :: TMVar a -> TMVar a -> Bool # (/=) :: TMVar a -> TMVar a -> Bool #

newTMVar :: MonadSTM m => a -> m (TMVar a) Source #

Lifted version of newTMVar

newEmptyTMVar :: MonadSTM m => m (TMVar a) Source #

Lifted version of newEmptyTMVar

newTMVarIO :: MonadIO m => a -> m (TMVar a) #

Lifted version of newTMVarIO

Since: unliftio-0.2.1.0

newEmptyTMVarIO :: MonadIO m => m (TMVar a) #

Lifted version of newEmptyTMVarIO

Since: unliftio-0.2.1.0

takeTMVar :: MonadSTM m => TMVar a -> m a Source #

Lifted version of takeTMVar

putTMVar :: MonadSTM m => TMVar a -> a -> m () Source #

Lifted version of putTMVar

readTMVar :: MonadSTM m => TMVar a -> m a Source #

Lifted version of readTMVar

tryReadTMVar :: MonadSTM m => TMVar a -> m (Maybe a) Source #

Lifted version of tryReadTMVar

swapTMVar :: MonadSTM m => TMVar a -> a -> m a Source #

Lifted version of swapTMVar

tryTakeTMVar :: MonadSTM m => TMVar a -> m (Maybe a) Source #

Lifted version of tryTakeTMVar

tryPutTMVar :: MonadSTM m => TMVar a -> a -> m Bool Source #

Lifted version of tryPutTMVar

isEmptyTMVar :: MonadSTM m => TMVar a -> m Bool Source #

Lifted version of isEmptyTMVar

mkWeakTMVar :: MonadUnliftIO m => TMVar a -> m () -> m (Weak (TMVar a)) #

Lifted version of mkWeakTMVar

Since: unliftio-0.2.1.0

TChan

data TChan a #

TChan is an abstract type representing an unbounded FIFO channel.

Instances

Instances details

Eq (TChan a)
Instance details Defined in Control.Concurrent.STM.TChan Methods (==) :: TChan a -> TChan a -> Bool # (/=) :: TChan a -> TChan a -> Bool #