-- Communicating Haskell Processes.
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module Control.Concurrent.CHP.Mutex where

import Control.Concurrent
import Control.Monad.Trans

type Mutex = MVar ()

claimMutex :: MonadIO m => Mutex -> m ()
claimMutex m = liftIO $ takeMVar m

newMutex :: MonadIO m => m Mutex
newMutex = liftIO $ newMVar ()

releaseMutex :: MonadIO m => Mutex -> m ()
releaseMutex m = liftIO $ putMVar m ()