6ed211f · streamly · git.iko.soy

git.iko.soy/streamly

Changes the signature of iterateM. Fixes #190.

Now, iterateM is (IsStream t, MonadAsync m) => (a -> m a) -> m a -> t m a

commit6ed211f28ace9805dc5c423cf91a80896311351e authorPranay Sashank <pranaysashank@gmail.com> dateWed 22 May 2019, 01:56 (7 years ago) parent22ccf96

2 files changed+45−17

compare with master

unifiedsplit

src/Streamly/Prelude.hs+6−6 test/Prop.hs+39−11

src/Streamly/Prelude.hs+6−6

@@ -774,7 +774,7 @@ iterate step = fromStream . go

774774

775775-- |

776776-- @

777−-- iterateM f m = m \`consM` iterateM f m

777+-- iterateM f m = m >>= \a -> return a \`consM` iterateM f (f a)

778778-- @

779779--

780780-- Generate an infinite stream with the first element generated by the action

@@ -788,21 +788,21 @@ iterate step = fromStream . go

788788--

789789-- @

790790-- drain $ serially $ S.take 10 $ S.iterateM

791−-- (\\x -> threadDelay 1000000 >> print x >> return (x + 1)) 0

791+-- (\\x -> threadDelay 1000000 >> print x >> return (x + 1)) (return 0)

792792--

793793-- drain $ asyncly $ S.take 10 $ S.iterateM

794−-- (\\x -> threadDelay 1000000 >> print x >> return (x + 1)) 0

794+-- (\\x -> threadDelay 1000000 >> print x >> return (x + 1)) (return 0)

795795-- @

796796--

797797-- /Concurrent/

798798--

799799-- @since 0.1.2

800−iterateM :: (IsStream t, MonadAsync m) => (a -> m a) -> a -> t m a

800+iterateM :: (IsStream t, MonadAsync m) => (a -> m a) -> m a -> t m a

801801iterateM step = go

802802 where

803803 go s = K.mkStream $ \st stp sng yld -> do

804− next <- step s

805− K.foldStreamShared st stp sng yld (return s |: go next)

804+ next <- s

805+ K.foldStreamShared st stp sng yld (return next |: go (step next))

806806

807807------------------------------------------------------------------------------

808808-- Conversions

test/Prop.hs+39−11

@@ -12,7 +12,7 @@ import Control.Exception

1212import Control.Monad (when, forM_, replicateM, replicateM_)

1313import Control.Monad.IO.Class (MonadIO(..))

1414import Data.Function ((&))

15−import Data.IORef (readIORef, modifyIORef, newIORef)

15+import Data.IORef (readIORef, modifyIORef, newIORef, modifyIORef', IORef)

1616import Data.List

1717 (sort, foldl', scanl', findIndices, findIndex, elemIndices,

1818 elemIndex, find, insertBy, intersperse, foldl1', (\\),

@@ -146,15 +146,33 @@ constructWithDoubleFromThenTo op l =

146146 in constructWithLen stream list op l

147147#endif

148148

149−constructWithIterate :: IsStream t => (t IO Int -> SerialT IO Int) -> Spec

150−constructWithIterate t = do

151− it "iterate" $

152− (S.toList . t . S.take 100) (S.iterate (+ 1) (0 :: Int))

153− `shouldReturn` take 100 (iterate (+ 1) 0)

154− it "iterateM" $ do

155− let addM y = return (y + 1)

156− S.toList . t . S.take 100 $ S.iterateM addM (0 :: Int)

157− `shouldReturn` take 100 (iterate (+ 1) 0)

149+constructWithIterate ::

150+ IsStream t => (t IO Int -> SerialT IO Int) -> Word8 -> Property

151+constructWithIterate op len =

152+ withMaxSuccess maxTestCount $

153+ monadicIO $ do

154+ stream <-

155+ run $

156+ (S.toList . op . S.take (fromIntegral len))

157+ (S.iterate (+ 1) (0 :: Int))

158+ let list = take (fromIntegral len) (iterate (+ 1) 0)

159+ listEquals (==) stream list

160+

161+constructWithIterateM ::

162+ IsStream t => (t IO Int -> SerialT IO Int) -> Word8 -> Property

163+constructWithIterateM op len =

164+ withMaxSuccess maxTestCount $

165+ monadicIO $ do

166+ mvl <- run (newIORef [] :: IO (IORef [Int]))

167+ let addM mv x y = modifyIORef' mv (++ [y + x]) >> return (y + x)

168+ list = take (fromIntegral len) (iterate (+ 1) 0)

169+ run $

170+ S.drain . op $

171+ S.take (fromIntegral len) $

172+ S.iterateM (addM mvl 1) (addM mvl 0 0 :: IO Int)

173+ streamEffect <- run $ readIORef mvl

174+ listEquals (==) streamEffect list

175+

158176

159177-------------------------------------------------------------------------------

160178-- Concurrent generation

@@ -971,8 +989,18 @@ main = hspec

971989 serialOps $ prop "serially DoubleFromThenTo" .

972990 constructWithDoubleFromThenTo

973991#endif

992+

993+ serialOps $ prop "serially iterate" . constructWithIterate

994+

974995 -- XXX test for all types of streams

975− constructWithIterate serially

996+ serialOps $ prop "serially iterateM" . constructWithIterateM

997+ -- take doesn't work well on concurrent streams. Even though it

998+ -- seems like take only has a problem when used with parallely.

999+ -- wSerialOps $ prop "wSerially iterateM" wSerially . constructWithIterate

1000+ -- aheadOps $ prop "aheadly iterateM" aheadly . onstructWithIterate

1001+ -- asyncOps $ prop "asyncly iterateM" asyncly . constructWithIterate

1002+ -- wAsyncOps $ prop "wAsyncly iterateM" wAsyncly . onstructWithIterate

1003+ -- parallelOps $ prop "parallely iterateM" parallely . onstructWithIterate

9761004 -- XXX add tests for fromIndices

9771005

9781006 describe "Functor operations" $ do