3cda01f · streamly · git.iko.soy

src/Streamly/Internal/Data/Consumer/Type.hsnew file+28

compare with master

unifiedsplit

@@ -0,0 +1,28 @@

1+-- |

2+-- Module : Streamly.Internal.Data.Consumer.Type

4+-- License : BSD-3-Clause

5+-- Maintainer : streamly@composewell.com

6+-- Stability : experimental

7+-- Portability : GHC

8+--

9+-- Consumer is to Fold as Unfold is to Stream.

10+--

11+module Streamly.Internal.Data.Consumer.Type

12+ (

13+ -- * Types

14+ Fold2 (..)

15+ )

16+where

17+

18+-- All folds in the Fold module should be implemented as Refolds.

19+--

20+-- | Experimental type to provide a side input to the fold for generating the

21+-- initial state. For example, if we have to fold chunks of a stream and write

22+-- each chunk to a different file, then we can generate the file name using a

23+-- monadic action. This is a generalized version of 'Fold'.

24+--

25+-- /Internal/

26+data Fold2 m c a b =

27+ -- | @Fold @ @ step @ @ inject @ @ extract@

28+ forall s. Fold2 (s -> a -> m s) (c -> m s) (s -> m b)

src/Streamly/Internal/Data/Fold/Type.hs+3−9

@@ -272,6 +272,7 @@ import Data.Maybe (isJust, fromJust)

272import Fusion.Plugin.Types (Fuse(..))

273import Streamly.Internal.Data.Maybe.Strict (Maybe'(..), toMaybe)

274import Streamly.Internal.Data.Tuple.Strict (Tuple'(..), Tuple3'(..))

275+import Streamly.Internal.Data.Consumer.Type (Fold2(..))

275

276

276import qualified Streamly.Internal.Data.Stream.StreamK.Type as K

277import qualified Streamly.Internal.Data.Stream.StreamK.Type as K

277

278

@@ -570,16 +571,9 @@ mkFoldM_ step initial = mkFoldM step initial return

570-- Fold2

571-- Fold2

571------------------------------------------------------------------------------

572------------------------------------------------------------------------------

572

573

573−-- | Experimental type to provide a side input to the fold for generating the

574+-- This is similar to how we run an Unfold to generate a Stream. A Fold is like

574−-- initial state. For example, if we have to fold chunks of a stream and write

575+-- a Stream and a Fold2 is like an Unfold.

575−-- each chunk to a different file, then we can generate the file name using a

576−-- monadic action. This is a generalized version of 'Fold'.

577--

576--

578−-- /Internal/

579−data Fold2 m c a b =

580− -- | @Fold @ @ step @ @ inject @ @ extract@

581− forall s. Fold2 (s -> a -> m s) (c -> m s) (s -> m b)

582−

583-- | Convert more general type 'Fold2' into a simpler type 'Fold'

577-- | Convert more general type 'Fold2' into a simpler type 'Fold'

584--

578--

585-- /Internal/

579-- /Internal/

streamly.cabal+1

@@ -385,6 +385,7 @@ library

385 , Streamly.Internal.Data.SVar.Pull

386 , Streamly.Internal.Data.SVar

387 , Streamly.Internal.Data.Stream.StreamK.Type

388+ , Streamly.Internal.Data.Consumer.Type

388 , Streamly.Internal.Data.Fold.Type

389 , Streamly.Internal.Data.Fold.Type

389 , Streamly.Internal.Data.Stream.StreamD.Step

390 , Streamly.Internal.Data.Stream.StreamD.Step

390 , Streamly.Internal.Data.Stream.StreamD.Type

391 , Streamly.Internal.Data.Stream.StreamD.Type