conduit-extra 0.1.1 → 0.1.2

raw patch · 3 files changed

+84/−2 lines, 3 filesdep +containersdep +monad-loopsdep +primitivedep ~conduit

Dependencies added: containers, monad-loops, primitive, vector

Dependency ranges changed: conduit

Files

• Data/Conduit/Extra/Utils.hs +65/−0
• Data/Conduit/Extra/ZipSink.hs +13/−1
• conduit-extra.cabal +6/−1

@@ -0,0 +1,65 @@+{- | Functions currently under development which have not been moved to their+     final destination.+-}++module Data.Conduit.Extra.Utils where++import           Control.Applicative+import           Control.Monad.Loops+import           Control.Monad.Primitive+import           Control.Monad.Trans.Class+import           Control.Monad.Trans.State+import           Data.Conduit+import           Data.Conduit.List as CL+import           Data.Foldable+import           Data.Sequence as Seq+import           Data.Vector as Boxed (Vector, freeze)+import           Data.Vector.Mutable as Boxed hiding (length)+import qualified Data.Vector.Unboxed as Unboxed+import qualified Data.Vector.Unboxed.Mutable as Unboxed++takeWhile :: Monad m => (a -> Bool) -> Conduit a m a+takeWhile f = loop where+    loop = await >>= maybe (return ()) go+    go x | f x = yield x >> loop+         | otherwise = leftover x++collect :: PrimMonad m => Int -> Sink a m (Vector a)+collect size = do+    v <- lift $ unsafeNew size+    forM_ [0..size-1] $ \i -> do+        me <- await+        case me of+            Nothing ->+                error $ "Too many elements for a vector of size "+                     ++ show size+            Just e  -> lift $ unsafeWrite v i e+    lift $ freeze v++collectUnboxed :: (PrimMonad m, Unboxed.Unbox a)+               => Int -> Sink a m (Unboxed.Vector a)+collectUnboxed size = do+    v <- lift $ Unboxed.unsafeNew size+    forM_ [0..size-1] $ \i -> do+        me <- await+        case me of+            Nothing ->+                error $ "Too many elements for an unboxed vector of size "+                     ++ show size+            Just e  -> lift $ Unboxed.unsafeWrite v i e+    lift $ Unboxed.freeze v++-- | Remove the last N elements from the stream.  This requires holding up to+--   N elements in memory.+dropRight :: Monad m => Int -> Conduit a m a+dropRight size = do+    xs <- Seq.fromList <$> CL.take size+    flip evalStateT xs $ whileM_ ((== size) . Seq.length <$> get) $ do+        xs' <- get+        case viewl xs' of+            EmptyL -> error "impossible"+            y :< ys -> do+                mz <- lift await+                case mz of+                    Nothing -> put Seq.empty+                    Just z  -> put (ys |> z) >> lift (yield y)

@@ -1,5 +1,16 @@-module Data.Conduit.Extra.ZipSink where+{-# LANGUAGE CPP #-}+module Data.Conduit.Extra.ZipSink+    ( ZipSink (..)+    , broadcast+    ) where +#if MIN_VERSION_conduit(1, 0, 13)+import Data.Conduit (ZipSink (..), sequenceSinks, Sink)+import Data.Traversable (Traversable)++broadcast :: (Traversable f, Monad m) => f (Sink i m r) -> Sink i m (f r)+broadcast = sequenceSinks+#else import Control.Applicative import Control.Monad import Data.Conduit as C@@ -31,3 +42,4 @@  broadcast :: (Traversable f, Monad m) => f (Sink i m r) -> Sink i m (f r) broadcast = getZipSink . sequenceA . fmap ZipSink+#endif

@@ -1,5 +1,5 @@ Name:                conduit-extra-Version:             0.1.1+Version:             0.1.2 Synopsis:            Experimental helper functions for conduit. Description:     This package is meant as a testing ground for new concepts in conduit. The idea is to have a much lower barrier to entry for this library relative to conduit itself. This way, conduit itself will continue to have a best-practices, minimal, stable API, while people are free to try crazy new features.@@ -17,10 +17,15 @@                      , Data.Conduit.Extra.Pipes                      , Data.Conduit.Extra.Resumable                      , Data.Conduit.Extra.ZipSink+                     , Data.Conduit.Extra.Utils   Build-depends:       base                     >= 4            && < 5                      , conduit                  >= 1.0                      , mtl+                     , monad-loops+                     , containers+                     , primitive                      , transformers+                     , vector                      , void   ghc-options:     -Wall