diff options
Diffstat (limited to 'Utility/TSet.hs')
| -rw-r--r-- | Utility/TSet.hs | 28 |
1 files changed, 15 insertions, 13 deletions
diff --git a/Utility/TSet.hs b/Utility/TSet.hs index bb711a4fb..c5ee22c89 100644 --- a/Utility/TSet.hs +++ b/Utility/TSet.hs @@ -1,6 +1,6 @@ {- Transactional sets - - - Copyright 2012 Joey Hess <joey@kitenet.net> + - Copyright 2012, 2013 Joey Hess <joey@kitenet.net> -} module Utility.TSet where @@ -11,18 +11,20 @@ import Control.Concurrent.STM type TSet = TChan -runTSet :: STM a -> IO a -runTSet = atomically - -newTSet :: IO (TSet a) -newTSet = atomically newTChan +newTSet :: STM (TSet a) +newTSet = newTChan {- Gets the contents of the TSet. Blocks until at least one item is - present. -} -getTSet :: TSet a -> IO [a] -getTSet tset = runTSet $ do +getTSet :: TSet a -> STM [a] +getTSet tset = do c <- readTChan tset - go [c] + l <- readTSet tset + return $ c:l + +{- Gets anything currently in the TSet, without blocking. -} +readTSet :: TSet a -> STM [a] +readTSet tset = go [] where go l = do v <- tryReadTChan tset @@ -31,9 +33,9 @@ getTSet tset = runTSet $ do Just c -> go (c:l) {- Puts items into a TSet. -} -putTSet :: TSet a -> [a] -> IO () -putTSet tset vs = runTSet $ mapM_ (writeTChan tset) vs +putTSet :: TSet a -> [a] -> STM () +putTSet tset vs = mapM_ (writeTChan tset) vs {- Put a single item into a TSet. -} -putTSet1 :: TSet a -> a -> IO () -putTSet1 tset v = void $ runTSet $ writeTChan tset v +putTSet1 :: TSet a -> a -> STM () +putTSet1 tset v = void $ writeTChan tset v |