potoki 0.9 → 0.9.1

raw patch · 2 files changed

+35/−1 lines, 2 filesdep +transformers

Dependencies added: transformers

Files

• library/Potoki/Transform.hs +33/−0
• potoki.cabal +2/−1

@@ -16,6 +16,7 @@   builderChunks,   executeIO,   mapInIO,+  state,   -- * Parsing   parseBytes,   parseText,@@ -44,6 +45,7 @@ import qualified Data.ByteString as J import qualified System.Directory as I import qualified Control.Concurrent.Chan.Unagi.Bounded as B+import qualified Control.Monad.Trans.State.Strict as O import qualified Potoki.Transform.Concurrency as N  @@ -188,3 +190,34 @@   Transform $ \ fetch -> do     Transform transformIO <- io     transformIO fetch++{-# INLINE state #-}+state :: (a -> O.State s [b]) -> s -> Transform a b+state stateFn initialState =+  Transform $ \ (A.Fetch fetchIO) -> do+    stateRef <- newIORef initialState+    bufferRef <- newIORef []+    return $ A.Fetch $ \ nil just -> do+      buffer <- readIORef bufferRef+      case buffer of+        head : tail -> do+          writeIORef bufferRef tail+          return (just head)+        _ ->+          let+            nilCase =+              return nil+            justCase input =+              do+                currentState <- readIORef stateRef+                case O.runState (stateFn input) currentState of+                  (outputList, newState) -> case outputList of+                    head : tail -> do+                      writeIORef bufferRef tail+                      writeIORef stateRef newState+                      return (just head)+                    _ -> do+                      writeIORef bufferRef []+                      writeIORef stateRef newState+                      return nil+            in join (fetchIO nilCase justCase)

@@ -1,7 +1,7 @@ name:   potoki version:-  0.9+  0.9.1 synopsis:   Simple streaming in IO description:@@ -87,6 +87,7 @@     potoki-core >=1.5 && <1.6,     profunctors >=5.2 && <6,     text >=1 && <2,+    transformers >=0.5 && <0.6,     unagi-chan >=0.4 && <0.5,     unordered-containers >=0.2 && <0.3,     vector >=0.12 && <0.13