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module Control.Concurrent.STM.Util where
import Control.Monad.IO.Class
import Control.Concurrent.STM
chanContents :: TChan x -> IO [x]
chanContents ch = do
x <- atomically $ do
bempty <- isEmptyTChan ch
if bempty
then return Nothing
else fmap Just $ readTChan ch
maybe (return [])
(\x -> do
xs <- chanContents ch
return (x:xs))
x
ioWriteChan :: MonadIO m => TChan a -> a -> m ()
ioWriteChan c v = liftIO . atomically $ writeTChan c v
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