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21 lines
619 B
21 lines
619 B
14 years ago
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module Data.Conduit.BufferedSource where
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import Control.Monad.IO.Class
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import Control.Monad.Trans.Class
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import Data.IORef
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import Data.Conduit
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import qualified Data.Conduit.List as CL
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-- | Buffered source from conduit 0.3
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bufferSource :: MonadIO m => Source m o -> IO (Source m o)
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bufferSource s = do
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srcRef <- newIORef s
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return $ do
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src <- liftIO $ readIORef srcRef
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let go src = do
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(src', res) <- lift $ src $$+ CL.head
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case res of
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Nothing -> return ()
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Just x -> liftIO (writeIORef srcRef src') >> yield x >> go src'
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in go src
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