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GHC 9.14.1 · lts/ghc-9.14.x · b2f3bfd · 2026-10-11

Moduleunliftio-0.2.25.1Haskell2010

UnliftIO.MVar

Unlifted Control.Concurrent.MVar.

1 type
17 values

Packageunliftio-0.2.25.1
Exports18
LanguageHaskell2010
LicenceMIT
SourceMVar.hs

datadata MVar a

An MVar (pronounced "em-var") is a synchronising variable, used for communication between concurrent threads. It can be thought of as a box, which may be empty or full.

Instances3NFData1, Eq, NFData

NFData1 MVarDefined in deepseq-1.5.1.0 · Control.DeepSeq
Eq (MVar a)Defined in ghc-internal-9.1401.0 · GHC.Internal.MVar
Compares the underlying pointers.
NFData (MVar a)Defined in deepseq-1.5.1.0 · Control.DeepSeq
NOTE: Only strict in the reference and not the referenced value.

valuenewEmptyMVar :: MonadIO m => m (MVar a)

Lifted newEmptyMVar.

valuenewMVar :: MonadIO m => a -> m (MVar a)

Lifted newMVar.

valuetakeMVar :: MonadIO m => MVar a -> m a

Lifted takeMVar.

valueputMVar :: MonadIO m => MVar a -> a -> m ()

Lifted putMVar.

valuereadMVar :: MonadIO m => MVar a -> m a

Lifted readMVar.

valueswapMVar :: MonadIO m => MVar a -> a -> m a

Lifted swapMVar.

valuetryTakeMVar :: MonadIO m => MVar a -> m (Maybe a)

Lifted tryTakeMVar.

valuetryPutMVar :: MonadIO m => MVar a -> a -> m Bool

Lifted tryPutMVar.

valueisEmptyMVar :: MonadIO m => MVar a -> m Bool

Lifted isEmptyMVar.

valuewithMVar :: MonadUnliftIO m => MVar a -> (a -> m b) -> m b

Unlifted withMVar.

valuewithMVarMasked :: MonadUnliftIO m => MVar a -> (a -> m b) -> m b

Unlifted withMVarMasked.

valuemodifyMVar :: MonadUnliftIO m => MVar a -> (a -> m (a, b)) -> m b

Unlifted modifyMVar.

valuemodifyMVar_ :: MonadUnliftIO m => MVar a -> (a -> m a) -> m ()

Unlifted modifyMVar_.

valuemodifyMVarMasked :: MonadUnliftIO m => MVar a -> (a -> m (a, b)) -> m b

Unlifted modifyMVarMasked.

valuemodifyMVarMasked_ :: MonadUnliftIO m => MVar a -> (a -> m a) -> m ()

Unlifted modifyMVarMasked_.

valuetryReadMVar :: MonadIO m => MVar a -> m (Maybe a)

Lifted tryReadMVar.

valuemkWeakMVar :: MonadUnliftIO m => MVar a -> m () -> m (Weak (MVar a))

Unlifted mkWeakMVar.