{-# LANGUAGE CPP #-}
{-# LANGUAGE UndecidableInstances #-}
-- |
-- Module      : Streamly.Internal.Data.StreamK.Type
-- Copyright   : (c) 2017 Composewell Technologies
--
-- License     : BSD3
-- Maintainer  : streamly@composewell.com
-- Stability   : experimental
-- Portability : GHC
--
--
-- Continuation passing style (CPS) stream implementation. The symbol 'K' below
-- denotes a function as well as a Kontinuation.
--
module Streamly.Internal.Data.StreamK.Type
    (
    -- * StreamK type
      Stream
    , StreamK (..)

    -- * CrossStreamK type wrapper
    , CrossStreamK
    , unCross
    , mkCross

    -- * foldr/build Fusion
    , mkStream
    , foldStream
    , foldStreamShared
    , foldrM
    , foldrS
    , foldrSShared
    , foldrSM
    , build
    , buildS
    , buildM
    , buildSM
    , augmentS
    , augmentSM
    , unShare

    -- * Construction
    -- ** Primitives
    , fromStopK
    , fromYieldK
    , consK
    , cons
    , (.:)
    , consM
    , consMBy
    , nil
    , nilM

    -- ** Unfolding
    , unfoldr
    , unfoldrMWith
    , unfoldrM

    -- ** From Values
    , fromEffect
    , fromPure
    , repeat
    , repeatMWith
    , replicateMWith

    -- ** From Indices
    , fromIndicesMWith

    -- ** Iteration
    , iterateMWith

    -- ** From Containers
    , fromFoldable
    , fromFoldableM

    -- ** Cyclic
    , mfix

    -- * Elimination
    -- ** Primitives
    , uncons

    -- ** Strict Left Folds
    , Streamly.Internal.Data.StreamK.Type.foldl'
    , foldlx'
    , foldlMx'
    , foldlM'

    -- ** Lazy Right Folds
    , Streamly.Internal.Data.StreamK.Type.foldr

    -- ** Specific Folds
    , drain
    , null
    , tail
    , init

    -- * Mapping
    , map
    , mapMWith
    , mapMSerial

    -- * Combining Two Streams
    -- ** Appending
    , conjoin
    , append

    -- ** Interleave
    , interleave
    , interleaveFst
    , interleaveMin

    -- ** Cross Product
    , crossApplyWith
    , crossApply
    , crossApplySnd
    , crossApplyFst
    , crossWith
    , cross

    -- * Concat
    , before
    , concatEffect
    , concatMapEffect
    , concatMapWith
    , concatMap
    , bindWith
    , concatIterateWith
    , concatIterateLeftsWith
    , concatIterateScanWith

    -- * Merge
    , mergeMapWith
    , mergeIterateWith

    -- * Buffered Operations
    , foldlS
    , reverse
    )
where

#include "inline.hs"

-- import Control.Applicative (liftA2)
import Control.Monad ((>=>))
import Control.Monad.Catch (MonadThrow, throwM)
import Control.Monad.Trans.Class (MonadTrans(lift))
#if !MIN_VERSION_base(4,18,0)
import Control.Applicative (liftA2)
#endif
import Control.Monad.IO.Class (MonadIO(..))
import Data.Foldable (Foldable(foldl'), fold, foldr)
import Data.Function (fix)
import Data.Functor.Identity (Identity(..))
import Data.Maybe (fromMaybe)
import Data.Semigroup (Endo(..))
import GHC.Exts (IsList(..), IsString(..), oneShot)
import Streamly.Internal.BaseCompat ((#.))
import Streamly.Internal.Data.Maybe.Strict (Maybe'(..), toMaybe)
import Streamly.Internal.Data.SVar.Type (State, adaptState, defState)
import Text.Read
       ( Lexeme(Ident), lexP, parens, prec, readPrec, readListPrec
       , readListPrecDefault)

import qualified Prelude

import Prelude hiding
    (map, mapM, concatMap, foldr, repeat, null, reverse, tail, init)

#include "DocTestDataStreamK.hs"

------------------------------------------------------------------------------
-- Basic stream type
------------------------------------------------------------------------------

-- It uses stop, singleton and yield continuations equivalent to the following
-- direct style type:
--
-- @
-- data StreamK m a = Stop | Singleton a | Yield a (StreamK m a)
-- @
--
-- To facilitate parallel composition we maintain a local state in an 'SVar'
-- that is shared across and is used for synchronization of the streams being
-- composed.
--
-- The singleton case can be expressed in terms of stop and yield but we have
-- it as a separate case to optimize composition operations for streams with
-- single element.  We build singleton streams in the implementation of 'pure'
-- for Applicative and Monad, and in 'lift' for MonadTrans.

-- XXX remove the State param.

-- | Continuation Passing Style (CPS) version of "Streamly.Data.Stream.Stream".
-- Unlike "Streamly.Data.Stream.Stream", 'StreamK' can be composed recursively
-- without affecting performance.
--
-- Semigroup instance appends two streams:
--
-- >>> (<>) = Stream.append
--
{-# DEPRECATED Stream "Please use StreamK instead." #-}
type Stream = StreamK

newtype StreamK m a =
    MkStream (forall r.
               State StreamK m a         -- state
            -> (a -> StreamK m a -> m r) -- yield
            -> (a -> m r)               -- singleton
            -> m r                      -- stop
            -> m r
            )

mkStream
    :: (forall r. State StreamK m a
        -> (a -> StreamK m a -> m r)
        -> (a -> m r)
        -> m r
        -> m r)
    -> StreamK m a
mkStream :: forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
MkStream

-- | A terminal function that has no continuation to follow.
type StopK m = forall r. m r -> m r

-- | A monadic continuation, it is a function that yields a value of type "a"
-- and calls the argument (a -> m r) as a continuation with that value. We can
-- also think of it as a callback with a handler (a -> m r).  Category
-- theorists call it a codensity type, a special type of right kan extension.
type YieldK m a = forall r. (a -> m r) -> m r

_wrapM :: Monad m => m a -> YieldK m a
_wrapM :: forall (m :: * -> *) a. Monad m => m a -> YieldK m a
_wrapM m a
m = (m a
m m a -> (a -> m r) -> m r
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>=)

-- | Make an empty stream from a stop function.
fromStopK :: StopK m -> StreamK m a
fromStopK :: forall (m :: * -> *) a. StopK m -> StreamK m a
fromStopK StopK m
k = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
_ a -> StreamK m a -> m r
_ a -> m r
_ m r
stp -> m r -> m r
StopK m
k m r
stp

-- | Make a singleton stream from a callback function. The callback function
-- calls the one-shot yield continuation to yield an element.
fromYieldK :: YieldK m a -> StreamK m a
fromYieldK :: forall (m :: * -> *) a. YieldK m a -> StreamK m a
fromYieldK YieldK m a
k = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
_ a -> StreamK m a -> m r
_ a -> m r
sng m r
_ -> (a -> m r) -> m r
YieldK m a
k a -> m r
sng

-- | Add a yield function at the head of the stream.
consK :: YieldK m a -> StreamK m a -> StreamK m a
consK :: forall (m :: * -> *) a. YieldK m a -> StreamK m a -> StreamK m a
consK YieldK m a
k StreamK m a
r = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
_ a -> StreamK m a -> m r
yld a -> m r
_ m r
_ -> (a -> m r) -> m r
YieldK m a
k (a -> StreamK m a -> m r
`yld` StreamK m a
r)

-- XXX Build a stream from a repeating callback function.

------------------------------------------------------------------------------
-- Construction
------------------------------------------------------------------------------

infixr 5 `cons`

-- faster than consM because there is no bind.

-- | A right associative prepend operation to add a pure value at the head of
-- an existing stream::
--
-- >>> s = 1 `StreamK.cons` 2 `StreamK.cons` 3 `StreamK.cons` StreamK.nil
-- >>> Stream.fold Fold.toList (StreamK.toStream s)
-- [1,2,3]
--
-- It can be used efficiently with 'Prelude.foldr':
--
-- >>> fromFoldable = Prelude.foldr StreamK.cons StreamK.nil
--
-- Same as the following but more efficient:
--
-- >>> cons x xs = return x `StreamK.consM` xs
--
{-# INLINE_NORMAL cons #-}
cons :: a -> StreamK m a -> StreamK m a
cons :: forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
cons a
a StreamK m a
r = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
_ a -> StreamK m a -> m r
yield a -> m r
_ m r
_ -> a -> StreamK m a -> m r
yield a
a StreamK m a
r

infixr 5 .:

-- | Operator equivalent of 'cons'.
--
-- @
-- > toList $ 1 .: 2 .: 3 .: nil
-- [1,2,3]
-- @
--
{-# INLINE (.:) #-}
(.:) :: a -> StreamK m a -> StreamK m a
.: :: forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
(.:) = a -> StreamK m a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
cons

-- | A stream that terminates without producing any output or side effect.
--
-- >>> Stream.fold Fold.toList (StreamK.toStream StreamK.nil)
-- []
--
{-# INLINE_NORMAL nil #-}
nil :: StreamK m a
nil :: forall (m :: * -> *) a. StreamK m a
nil = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
_ a -> StreamK m a -> m r
_ a -> m r
_ m r
stp -> m r
stp

-- | A stream that terminates without producing any output, but produces a side
-- effect.
--
-- >>> Stream.fold Fold.toList (StreamK.toStream (StreamK.nilM (print "nil")))
-- "nil"
-- []
--
-- /Pre-release/
{-# INLINE_NORMAL nilM #-}
nilM :: Applicative m => m b -> StreamK m a
nilM :: forall (m :: * -> *) b a. Applicative m => m b -> StreamK m a
nilM m b
m = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
_ a -> StreamK m a -> m r
_ a -> m r
_ m r
stp -> m b
m m b -> m r -> m r
forall a b. m a -> m b -> m b
forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
*> m r
stp

-- Create a singleton stream from a pure value.
--
-- >>> fromPure a = a `StreamK.cons` StreamK.nil
-- >>> fromPure = pure
-- >>> fromPure = StreamK.fromEffect . pure
--
{-# INLINE_NORMAL fromPure #-}
fromPure :: a -> StreamK m a
fromPure :: forall a (m :: * -> *). a -> StreamK m a
fromPure a
a = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
_ a -> StreamK m a -> m r
_ a -> m r
single m r
_ -> a -> m r
single a
a

-- Create a singleton stream from a monadic action.
--
-- >>> fromEffect m = m `StreamK.consM` StreamK.nil
--
-- >>> Stream.fold Fold.drain $ StreamK.toStream $ StreamK.fromEffect (putStrLn "hello")
-- hello
--
{-# INLINE_NORMAL fromEffect #-}
fromEffect :: Monad m => m a -> StreamK m a
fromEffect :: forall (m :: * -> *) a. Monad m => m a -> StreamK m a
fromEffect m a
m = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
_ a -> StreamK m a -> m r
_ a -> m r
single m r
_ -> m a
m m a -> (a -> m r) -> m r
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= a -> m r
single

infixr 5 `consM`

-- NOTE: specializing the function outside the instance definition seems to
-- improve performance quite a bit at times, even if we have the same
-- SPECIALIZE in the instance definition.

-- | A right associative prepend operation to add an effectful value at the
-- head of an existing stream::
--
-- >>> s = putStrLn "hello" `StreamK.consM` putStrLn "world" `StreamK.consM` StreamK.nil
-- >>> Stream.fold Fold.drain (StreamK.toStream s)
-- hello
-- world
--
-- It can be used efficiently with 'Prelude.foldr':
--
-- >>> fromFoldableM = Prelude.foldr StreamK.consM StreamK.nil
--
-- Same as the following but more efficient:
--
-- >>> consM x xs = StreamK.fromEffect x `StreamK.append` xs
--
{-# INLINE consM #-}
{-# SPECIALIZE consM :: IO a -> StreamK IO a -> StreamK IO a #-}
consM :: Monad m => m a -> StreamK m a -> StreamK m a
consM :: forall (m :: * -> *) a.
Monad m =>
m a -> StreamK m a -> StreamK m a
consM m a
m StreamK m a
r = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
MkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
_ a -> StreamK m a -> m r
yld a -> m r
_ m r
_ -> m a
m m a -> (a -> m r) -> m r
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= (a -> StreamK m a -> m r
`yld` StreamK m a
r)

-- XXX specialize to IO?
{-# INLINE consMBy #-}
consMBy :: Monad m =>
    (StreamK m a -> StreamK m a -> StreamK m a) -> m a -> StreamK m a -> StreamK m a
consMBy :: forall (m :: * -> *) a.
Monad m =>
(StreamK m a -> StreamK m a -> StreamK m a)
-> m a -> StreamK m a -> StreamK m a
consMBy StreamK m a -> StreamK m a -> StreamK m a
f m a
m StreamK m a
r = m a -> StreamK m a
forall (m :: * -> *) a. Monad m => m a -> StreamK m a
fromEffect m a
m StreamK m a -> StreamK m a -> StreamK m a
`f` StreamK m a
r

------------------------------------------------------------------------------
-- Folding a stream
------------------------------------------------------------------------------

-- | Fold a stream by providing an SVar, a stop continuation, a singleton
-- continuation and a yield continuation. The stream would share the current
-- SVar passed via the State.
{-# INLINE_EARLY foldStreamShared #-}
foldStreamShared
    :: State StreamK m a
    -> (a -> StreamK m a -> m r)
    -> (a -> m r)
    -> m r
    -> StreamK m a
    -> m r
foldStreamShared :: forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m a
s a -> StreamK m a -> m r
yield a -> m r
single m r
stop (MkStream forall r.
State StreamK m a
-> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r
k) = State StreamK m a
-> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r
forall r.
State StreamK m a
-> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r
k State StreamK m a
s a -> StreamK m a -> m r
yield a -> m r
single m r
stop

-- | Fold a stream by providing a State, stop continuation, a singleton
-- continuation and a yield continuation. The stream will not use the SVar
-- passed via State.
{-# INLINE foldStream #-}
foldStream
    :: State StreamK m a
    -> (a -> StreamK m a -> m r)
    -> (a -> m r)
    -> m r
    -> StreamK m a
    -> m r
foldStream :: forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
s a -> StreamK m a -> m r
yield a -> m r
single m r
stop (MkStream forall r.
State StreamK m a
-> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r
k) =
    State StreamK m a
-> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r
forall r.
State StreamK m a
-> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r
k (State StreamK m a -> State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m a
s) a -> StreamK m a -> m r
yield a -> m r
single m r
stop

-------------------------------------------------------------------------------
-- foldr/build fusion
-------------------------------------------------------------------------------

-- XXX perhaps we can just use foldrSM/buildM everywhere as they are more
-- general and cover foldrS/buildS as well.

-- | The function 'f' decides how to reconstruct the stream. We could
-- reconstruct using a shared state (SVar) or without sharing the state.
--
{-# INLINE foldrSWith #-}
foldrSWith ::
    (forall r. State StreamK m b
        -> (b -> StreamK m b -> m r)
        -> (b -> m r)
        -> m r
        -> StreamK m b
        -> m r)
    -> (a -> StreamK m b -> StreamK m b)
    -> StreamK m b
    -> StreamK m a
    -> StreamK m b
foldrSWith :: forall (m :: * -> *) b a.
(forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r)
 -> (b -> m r)
 -> m r
 -> StreamK m b
 -> m r)
-> (a -> StreamK m b -> StreamK m b)
-> StreamK m b
-> StreamK m a
-> StreamK m b
foldrSWith forall r.
State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
f a -> StreamK m b -> StreamK m b
step StreamK m b
final StreamK m a
m = StreamK m a -> StreamK m b
go StreamK m a
m
    where
    go :: StreamK m a -> StreamK m b
go StreamK m a
m1 = (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m b
  -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
 -> StreamK m b)
-> (forall r.
    State StreamK m b
    -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall a b. (a -> b) -> a -> b
$ \State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp ->
        let run :: StreamK m b -> m r
run StreamK m b
x = State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall r.
State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
f State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp StreamK m b
x
            stop :: m r
stop = StreamK m b -> m r
run StreamK m b
final
            single :: a -> m r
single a
a = StreamK m b -> m r
run (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ a -> StreamK m b -> StreamK m b
step a
a StreamK m b
final
            yieldk :: a -> StreamK m a -> m r
yieldk a
a StreamK m a
r = StreamK m b -> m r
run (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ a -> StreamK m b -> StreamK m b
step a
a (StreamK m a -> StreamK m b
go StreamK m a
r)
         -- XXX if type a and b are the same we do not need adaptState, can we
         -- save some perf with that?
         -- XXX since we are using adaptState anyway here we can use
         -- foldStreamShared instead, will that save some perf?
         in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m b -> State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m b
st) a -> StreamK m a -> m r
yieldk a -> m r
single m r
stop StreamK m a
m1

-- XXX we can use rewrite rules just for foldrSWith, if the function f is the
-- same we can rewrite it.

-- | Fold sharing the SVar state within the reconstructed stream
{-# INLINE_NORMAL foldrSShared #-}
foldrSShared ::
       (a -> StreamK m b -> StreamK m b)
    -> StreamK m b
    -> StreamK m a
    -> StreamK m b
foldrSShared :: forall a (m :: * -> *) b.
(a -> StreamK m b -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
foldrSShared = (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r)
 -> (b -> m r)
 -> m r
 -> StreamK m b
 -> m r)
-> (a -> StreamK m b -> StreamK m b)
-> StreamK m b
-> StreamK m a
-> StreamK m b
forall (m :: * -> *) b a.
(forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r)
 -> (b -> m r)
 -> m r
 -> StreamK m b
 -> m r)
-> (a -> StreamK m b -> StreamK m b)
-> StreamK m b
-> StreamK m a
-> StreamK m b
foldrSWith State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall r.
State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared

-- XXX consM is a typeclass method, therefore rewritten already. Instead maybe
-- we can make consM polymorphic using rewrite rules.
-- {-# RULES "foldrSShared/id"     foldrSShared consM nil = \x -> x #-}
{-# RULES "foldrSShared/nil"
    forall k z. foldrSShared k z nil = z #-}
{-# RULES "foldrSShared/single"
    forall k z x. foldrSShared k z (fromPure x) = k x z #-}
-- {-# RULES "foldrSShared/app" [1]
--     forall ys. foldrSShared consM ys = \xs -> xs `conjoin` ys #-}

-- | Right fold to a streaming monad.
--
-- > foldrS StreamK.cons StreamK.nil === id
--
-- 'foldrS' can be used to perform stateless stream to stream transformations
-- like map and filter in general. It can be coupled with a scan to perform
-- stateful transformations. However, note that the custom map and filter
-- routines can be much more efficient than this due to better stream fusion.
--
-- >>> input = StreamK.fromStream $ Stream.fromList [1..5]
-- >>> Stream.fold Fold.toList $ StreamK.toStream $ StreamK.foldrS StreamK.cons StreamK.nil input
-- [1,2,3,4,5]
--
-- Find if any element in the stream is 'True':
--
-- >>> step x xs = if odd x then StreamK.fromPure True else xs
-- >>> input = StreamK.fromStream (Stream.fromList (2:4:5:undefined)) :: StreamK IO Int
-- >>> Stream.fold Fold.toList $ StreamK.toStream $ StreamK.foldrS step (StreamK.fromPure False) input
-- [True]
--
-- Map (+2) on odd elements and filter out the even elements:
--
-- >>> step x xs = if odd x then (x + 2) `StreamK.cons` xs else xs
-- >>> input = StreamK.fromStream (Stream.fromList [1..5]) :: StreamK IO Int
-- >>> Stream.fold Fold.toList $ StreamK.toStream $ StreamK.foldrS step StreamK.nil input
-- [3,5,7]
--
-- /Pre-release/
{-# INLINE_NORMAL foldrS #-}
foldrS ::
       (a -> StreamK m b -> StreamK m b)
    -> StreamK m b
    -> StreamK m a
    -> StreamK m b
foldrS :: forall a (m :: * -> *) b.
(a -> StreamK m b -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
foldrS = (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r)
 -> (b -> m r)
 -> m r
 -> StreamK m b
 -> m r)
-> (a -> StreamK m b -> StreamK m b)
-> StreamK m b
-> StreamK m a
-> StreamK m b
forall (m :: * -> *) b a.
(forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r)
 -> (b -> m r)
 -> m r
 -> StreamK m b
 -> m r)
-> (a -> StreamK m b -> StreamK m b)
-> StreamK m b
-> StreamK m a
-> StreamK m b
foldrSWith State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall r.
State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream

{-# RULES "foldrS/id"     foldrS cons nil = \x -> x #-}
{-# RULES "foldrS/nil"    forall k z.   foldrS k z nil  = z #-}
-- See notes in GHC.Base about this rule
-- {-# RULES "foldr/cons"
--  forall k z x xs. foldrS k z (x `cons` xs) = k x (foldrS k z xs) #-}
{-# RULES "foldrS/single" forall k z x. foldrS k z (fromPure x) = k x z #-}
-- {-# RULES "foldrS/app" [1]
--  forall ys. foldrS cons ys = \xs -> xs `conjoin` ys #-}

-------------------------------------------------------------------------------
-- foldrS with monadic cons i.e. consM
-------------------------------------------------------------------------------

{-# INLINE foldrSMWith #-}
foldrSMWith :: Monad m
    => (forall r. State StreamK m b
        -> (b -> StreamK m b -> m r)
        -> (b -> m r)
        -> m r
        -> StreamK m b
        -> m r)
    -> (m a -> StreamK m b -> StreamK m b)
    -> StreamK m b
    -> StreamK m a
    -> StreamK m b
foldrSMWith :: forall (m :: * -> *) b a.
Monad m =>
(forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r)
 -> (b -> m r)
 -> m r
 -> StreamK m b
 -> m r)
-> (m a -> StreamK m b -> StreamK m b)
-> StreamK m b
-> StreamK m a
-> StreamK m b
foldrSMWith forall r.
State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
f m a -> StreamK m b -> StreamK m b
step StreamK m b
final StreamK m a
m = StreamK m a -> StreamK m b
go StreamK m a
m
    where
    go :: StreamK m a -> StreamK m b
go StreamK m a
m1 = (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m b
  -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
 -> StreamK m b)
-> (forall r.
    State StreamK m b
    -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall a b. (a -> b) -> a -> b
$ \State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp ->
        let run :: StreamK m b -> m r
run StreamK m b
x = State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall r.
State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
f State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp StreamK m b
x
            stop :: m r
stop = StreamK m b -> m r
run StreamK m b
final
            single :: a -> m r
single a
a = StreamK m b -> m r
run (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ m a -> StreamK m b -> StreamK m b
step (a -> m a
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return a
a) StreamK m b
final
            yieldk :: a -> StreamK m a -> m r
yieldk a
a StreamK m a
r = StreamK m b -> m r
run (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ m a -> StreamK m b -> StreamK m b
step (a -> m a
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return a
a) (StreamK m a -> StreamK m b
go StreamK m a
r)
         in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m b -> State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m b
st) a -> StreamK m a -> m r
yieldk a -> m r
single m r
stop StreamK m a
m1

{-# INLINE_NORMAL foldrSM #-}
foldrSM :: Monad m
    => (m a -> StreamK m b -> StreamK m b)
    -> StreamK m b
    -> StreamK m a
    -> StreamK m b
foldrSM :: forall (m :: * -> *) a b.
Monad m =>
(m a -> StreamK m b -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
foldrSM = (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r)
 -> (b -> m r)
 -> m r
 -> StreamK m b
 -> m r)
-> (m a -> StreamK m b -> StreamK m b)
-> StreamK m b
-> StreamK m a
-> StreamK m b
forall (m :: * -> *) b a.
Monad m =>
(forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r)
 -> (b -> m r)
 -> m r
 -> StreamK m b
 -> m r)
-> (m a -> StreamK m b -> StreamK m b)
-> StreamK m b
-> StreamK m a
-> StreamK m b
foldrSMWith State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall r.
State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream

-- {-# RULES "foldrSM/id"     foldrSM consM nil = \x -> x #-}
{-# RULES "foldrSM/nil"    forall k z.   foldrSM k z nil  = z #-}
{-# RULES "foldrSM/single" forall k z x. foldrSM k z (fromEffect x) = k x z #-}
-- {-# RULES "foldrSM/app" [1]
--  forall ys. foldrSM consM ys = \xs -> xs `conjoin` ys #-}

-- Like foldrSM but sharing the SVar state within the recostructed stream.
{-# INLINE_NORMAL foldrSMShared #-}
foldrSMShared :: Monad m
    => (m a -> StreamK m b -> StreamK m b)
    -> StreamK m b
    -> StreamK m a
    -> StreamK m b
foldrSMShared :: forall (m :: * -> *) a b.
Monad m =>
(m a -> StreamK m b -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
foldrSMShared = (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r)
 -> (b -> m r)
 -> m r
 -> StreamK m b
 -> m r)
-> (m a -> StreamK m b -> StreamK m b)
-> StreamK m b
-> StreamK m a
-> StreamK m b
forall (m :: * -> *) b a.
Monad m =>
(forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r)
 -> (b -> m r)
 -> m r
 -> StreamK m b
 -> m r)
-> (m a -> StreamK m b -> StreamK m b)
-> StreamK m b
-> StreamK m a
-> StreamK m b
foldrSMWith State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall r.
State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared

-- {-# RULES "foldrSM/id"     foldrSM consM nil = \x -> x #-}
{-# RULES "foldrSMShared/nil"
    forall k z. foldrSMShared k z nil = z #-}
{-# RULES "foldrSMShared/single"
    forall k z x. foldrSMShared k z (fromEffect x) = k x z #-}
-- {-# RULES "foldrSM/app" [1]
--  forall ys. foldrSM consM ys = \xs -> xs `conjoin` ys #-}

-------------------------------------------------------------------------------
-- build
-------------------------------------------------------------------------------

{-# INLINE_NORMAL build #-}
build :: forall m a. (forall b. (a -> b -> b) -> b -> b) -> StreamK m a
build :: forall (m :: * -> *) a.
(forall b. (a -> b -> b) -> b -> b) -> StreamK m a
build forall b. (a -> b -> b) -> b -> b
g = (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a
forall b. (a -> b -> b) -> b -> b
g a -> StreamK m a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
cons StreamK m a
forall (m :: * -> *) a. StreamK m a
nil

{-# RULES "foldrM/build"
    forall k z (g :: forall b. (a -> b -> b) -> b -> b).
    foldrM k z (build g) = g k z #-}

{-# RULES "foldrS/build"
      forall k z (g :: forall b. (a -> b -> b) -> b -> b).
      foldrS k z (build g) = g k z #-}

{-# RULES "foldrS/cons/build"
      forall k z x (g :: forall b. (a -> b -> b) -> b -> b).
      foldrS k z (x `cons` build g) = k x (g k z) #-}

{-# RULES "foldrSShared/build"
      forall k z (g :: forall b. (a -> b -> b) -> b -> b).
      foldrSShared k z (build g) = g k z #-}

{-# RULES "foldrSShared/cons/build"
      forall k z x (g :: forall b. (a -> b -> b) -> b -> b).
      foldrSShared k z (x `cons` build g) = k x (g k z) #-}

-- build a stream by applying cons and nil to a build function
{-# INLINE_NORMAL buildS #-}
buildS ::
       ((a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
    -> StreamK m a
buildS :: forall a (m :: * -> *).
((a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
-> StreamK m a
buildS (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a
g = (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a
g a -> StreamK m a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
cons StreamK m a
forall (m :: * -> *) a. StreamK m a
nil

{-# RULES "foldrS/buildS"
      forall k z
        (g :: (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a).
      foldrS k z (buildS g) = g k z #-}

{-# RULES "foldrS/cons/buildS"
      forall k z x
        (g :: (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a).
      foldrS k z (x `cons` buildS g) = k x (g k z) #-}

{-# RULES "foldrSShared/buildS"
      forall k z
        (g :: (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a).
      foldrSShared k z (buildS g) = g k z #-}

{-# RULES "foldrSShared/cons/buildS"
      forall k z x
        (g :: (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a).
      foldrSShared k z (x `cons` buildS g) = k x (g k z) #-}

-- build a stream by applying consM and nil to a build function
{-# INLINE_NORMAL buildSM #-}
buildSM :: Monad m
    => ((m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
    -> StreamK m a
buildSM :: forall (m :: * -> *) a.
Monad m =>
((m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
-> StreamK m a
buildSM (m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a
g = (m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a
g m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) a.
Monad m =>
m a -> StreamK m a -> StreamK m a
consM StreamK m a
forall (m :: * -> *) a. StreamK m a
nil

{-# RULES "foldrSM/buildSM"
     forall k z
        (g :: (m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a).
     foldrSM k z (buildSM g) = g k z #-}

{-# RULES "foldrSMShared/buildSM"
     forall k z
        (g :: (m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a).
     foldrSMShared k z (buildSM g) = g k z #-}

-- Disabled because this may not fire as consM is a class Op
{-
{-# RULES "foldrS/consM/buildSM"
      forall k z x (g :: (m a -> t m a -> t m a) -> t m a -> t m a)
    . foldrSM k z (x `consM` buildSM g)
    = k x (g k z)
#-}
-}

-- Build using monadic build functions (continuations) instead of
-- reconstructing a stream.
{-# INLINE_NORMAL buildM #-}
buildM :: Monad m
    => (forall r. (a -> StreamK m a -> m r)
        -> (a -> m r)
        -> m r
        -> m r
       )
    -> StreamK m a
buildM :: forall (m :: * -> *) a.
Monad m =>
(forall r. (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
buildM forall r. (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r
g = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
    (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r
forall r. (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r
g (\a
a StreamK m a
r -> State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp (a -> m a
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return a
a m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) a.
Monad m =>
m a -> StreamK m a -> StreamK m a
`consM` StreamK m a
r)) a -> m r
sng m r
stp

-- | Like 'buildM' but shares the SVar state across computations.
{-# INLINE_NORMAL sharedMWith #-}
sharedMWith :: Monad m
    => (m a -> StreamK m a -> StreamK m a)
    -> (forall r. (a -> StreamK m a -> m r)
        -> (a -> m r)
        -> m r
        -> m r
       )
    -> StreamK m a
sharedMWith :: forall (m :: * -> *) a.
Monad m =>
(m a -> StreamK m a -> StreamK m a)
-> (forall r.
    (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
sharedMWith m a -> StreamK m a -> StreamK m a
cns forall r. (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r
g = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
    (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r
forall r. (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r
g (\a
a StreamK m a
r -> State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp (a -> m a
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return a
a m a -> StreamK m a -> StreamK m a
`cns` StreamK m a
r)) a -> m r
sng m r
stp

-------------------------------------------------------------------------------
-- augment
-------------------------------------------------------------------------------

{-# INLINE_NORMAL augmentS #-}
augmentS ::
       ((a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
    -> StreamK m a
    -> StreamK m a
augmentS :: forall a (m :: * -> *).
((a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
-> StreamK m a -> StreamK m a
augmentS (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a
g StreamK m a
xs = (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a
g a -> StreamK m a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
cons StreamK m a
xs

{-# RULES "augmentS/nil"
    forall (g :: (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a).
    augmentS g nil = buildS g
    #-}

{-# RULES "foldrS/augmentS"
    forall k z xs
        (g :: (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a).
    foldrS k z (augmentS g xs) = g k (foldrS k z xs)
    #-}

{-# RULES "augmentS/buildS"
    forall (g :: (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
           (h :: (a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a).
    augmentS g (buildS h) = buildS (\c n -> g c (h c n))
    #-}

{-# INLINE_NORMAL augmentSM #-}
augmentSM :: Monad m =>
       ((m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
    -> StreamK m a -> StreamK m a
augmentSM :: forall (m :: * -> *) a.
Monad m =>
((m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
-> StreamK m a -> StreamK m a
augmentSM (m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a
g StreamK m a
xs = (m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a
g m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) a.
Monad m =>
m a -> StreamK m a -> StreamK m a
consM StreamK m a
xs

{-# RULES "augmentSM/nil"
    forall
        (g :: (m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a).
    augmentSM g nil = buildSM g
    #-}

{-# RULES "foldrSM/augmentSM"
    forall k z xs
        (g :: (m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a).
    foldrSM k z (augmentSM g xs) = g k (foldrSM k z xs)
    #-}

{-# RULES "augmentSM/buildSM"
    forall
        (g :: (m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
        (h :: (m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a).
    augmentSM g (buildSM h) = buildSM (\c n -> g c (h c n))
    #-}

-------------------------------------------------------------------------------
-- Experimental foldrM/buildM
-------------------------------------------------------------------------------

-- | Lazy right fold with a monadic step function.
{-# INLINE_NORMAL foldrM #-}
foldrM :: (a -> m b -> m b) -> m b -> StreamK m a -> m b
foldrM :: forall a (m :: * -> *) b.
(a -> m b -> m b) -> m b -> StreamK m a -> m b
foldrM a -> m b -> m b
step m b
acc StreamK m a
m = StreamK m a -> m b
go StreamK m a
m
    where
    go :: StreamK m a -> m b
go StreamK m a
m1 =
        let stop :: m b
stop = m b
acc
            single :: a -> m b
single a
a = a -> m b -> m b
step a
a m b
acc
            yieldk :: a -> StreamK m a -> m b
yieldk a
a StreamK m a
r = a -> m b -> m b
step a
a (StreamK m a -> m b
go StreamK m a
r)
        in State StreamK m a
-> (a -> StreamK m a -> m b)
-> (a -> m b)
-> m b
-> StreamK m a
-> m b
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a. State t m a
defState a -> StreamK m a -> m b
yieldk a -> m b
single m b
stop StreamK m a
m1

{-# INLINE_NORMAL foldrMKWith #-}
foldrMKWith
    :: (State StreamK m a
        -> (a -> StreamK m a -> m b)
        -> (a -> m b)
        -> m b
        -> StreamK m a
        -> m b)
    -> (a -> m b -> m b)
    -> m b
    -> ((a -> StreamK m a -> m b) -> (a -> m b) -> m b -> m b)
    -> m b
foldrMKWith :: forall (m :: * -> *) a b.
(State StreamK m a
 -> (a -> StreamK m a -> m b)
 -> (a -> m b)
 -> m b
 -> StreamK m a
 -> m b)
-> (a -> m b -> m b)
-> m b
-> ((a -> StreamK m a -> m b) -> (a -> m b) -> m b -> m b)
-> m b
foldrMKWith State StreamK m a
-> (a -> StreamK m a -> m b)
-> (a -> m b)
-> m b
-> StreamK m a
-> m b
f a -> m b -> m b
step m b
acc = ((a -> StreamK m a -> m b) -> (a -> m b) -> m b -> m b) -> m b
go
    where
    go :: ((a -> StreamK m a -> m b) -> (a -> m b) -> m b -> m b) -> m b
go (a -> StreamK m a -> m b) -> (a -> m b) -> m b -> m b
k =
        let stop :: m b
stop = m b
acc
            single :: a -> m b
single a
a = a -> m b -> m b
step a
a m b
acc
            yieldk :: a -> StreamK m a -> m b
yieldk a
a StreamK m a
r = a -> m b -> m b
step a
a (((a -> StreamK m a -> m b) -> (a -> m b) -> m b -> m b) -> m b
go (\a -> StreamK m a -> m b
yld a -> m b
sng m b
stp -> State StreamK m a
-> (a -> StreamK m a -> m b)
-> (a -> m b)
-> m b
-> StreamK m a
-> m b
f State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a. State t m a
defState a -> StreamK m a -> m b
yld a -> m b
sng m b
stp StreamK m a
r))
        in (a -> StreamK m a -> m b) -> (a -> m b) -> m b -> m b
k a -> StreamK m a -> m b
yieldk a -> m b
single m b
stop

{-
{-# RULES "foldrM/buildS"
      forall k z (g :: (a -> t m a -> t m a) -> t m a -> t m a)
    . foldrM k z (buildS g)
    = g k z
#-}
-}
-- XXX in which case will foldrM/buildM fusion be useful?
{-# RULES "foldrM/buildM"
    forall step acc (g :: (forall r.
           (a -> StreamK m a -> m r)
        -> (a -> m r)
        -> m r
        -> m r
       )).
    foldrM step acc (buildM g) = foldrMKWith foldStream step acc g
    #-}

{-
{-# RULES "foldrM/sharedM"
    forall step acc (g :: (forall r.
           (a -> StreamK m a -> m r)
        -> (a -> m r)
        -> m r
        -> m r
       )).
    foldrM step acc (sharedM g) = foldrMKWith foldStreamShared step acc g
    #-}
-}

------------------------------------------------------------------------------
-- Left fold
------------------------------------------------------------------------------

-- | Strict left fold with an extraction function. Like the standard strict
-- left fold, but applies a user supplied extraction function (the third
-- argument) to the folded value at the end. This is designed to work with the
-- @foldl@ library. The suffix @x@ is a mnemonic for extraction.
--
-- Note that the accumulator is always evaluated including the initial value.
{-# INLINE foldlx' #-}
foldlx' :: forall m a b x. Monad m
    => (x -> a -> x) -> x -> (x -> b) -> StreamK m a -> m b
foldlx' :: forall (m :: * -> *) a b x.
Monad m =>
(x -> a -> x) -> x -> (x -> b) -> StreamK m a -> m b
foldlx' x -> a -> x
step x
begin x -> b
done StreamK m a
m = StreamK m x -> m b
get (StreamK m x -> m b) -> StreamK m x -> m b
forall a b. (a -> b) -> a -> b
$ StreamK m a -> x -> StreamK m x
go StreamK m a
m x
begin
    where
    {-# NOINLINE get #-}
    get :: StreamK m x -> m b
    get :: StreamK m x -> m b
get StreamK m x
m1 =
        -- XXX we are not strictly evaluating the accumulator here. Is this
        -- okay?
        let single :: x -> m b
single = b -> m b
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return (b -> m b) -> (x -> b) -> x -> m b
forall b c a. (b -> c) -> (a -> b) -> a -> c
. x -> b
done
        -- XXX this is foldSingleton. why foldStreamShared?
         in State StreamK m x
-> (x -> StreamK m x -> m b)
-> (x -> m b)
-> m b
-> StreamK m x
-> m b
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m x
forall a. HasCallStack => a
undefined x -> StreamK m x -> m b
forall a. HasCallStack => a
undefined x -> m b
single m b
forall a. HasCallStack => a
undefined StreamK m x
m1

    -- Note, this can be implemented by making a recursive call to "go",
    -- however that is more expensive because of unnecessary recursion
    -- that cannot be tail call optimized. Unfolding recursion explicitly via
    -- continuations is much more efficient.
    go :: StreamK m a -> x -> StreamK m x
    go :: StreamK m a -> x -> StreamK m x
go StreamK m a
m1 !x
acc = (forall r.
 State StreamK m x
 -> (x -> StreamK m x -> m r) -> (x -> m r) -> m r -> m r)
-> StreamK m x
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m x
  -> (x -> StreamK m x -> m r) -> (x -> m r) -> m r -> m r)
 -> StreamK m x)
-> (forall r.
    State StreamK m x
    -> (x -> StreamK m x -> m r) -> (x -> m r) -> m r -> m r)
-> StreamK m x
forall a b. (a -> b) -> a -> b
$ \State StreamK m x
_ x -> StreamK m x -> m r
yld x -> m r
sng m r
_ ->
        let stop :: m r
stop = x -> m r
sng x
acc
            single :: a -> m r
single a
a = x -> m r
sng (x -> m r) -> x -> m r
forall a b. (a -> b) -> a -> b
$ x -> a -> x
step x
acc a
a
            -- XXX this is foldNonEmptyStream
            yieldk :: a -> StreamK m a -> m r
yieldk a
a StreamK m a
r = State StreamK m x
-> (x -> StreamK m x -> m r)
-> (x -> m r)
-> m r
-> StreamK m x
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m x
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a. State t m a
defState x -> StreamK m x -> m r
yld x -> m r
sng m r
forall a. HasCallStack => a
undefined (StreamK m x -> m r) -> StreamK m x -> m r
forall a b. (a -> b) -> a -> b
$
                StreamK m a -> x -> StreamK m x
go StreamK m a
r (x -> a -> x
step x
acc a
a)
        in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a. State t m a
defState a -> StreamK m a -> m r
yieldk a -> m r
single m r
stop StreamK m a
m1

-- | Strict left associative fold.
{-# INLINE foldl' #-}
foldl' :: Monad m => (b -> a -> b) -> b -> StreamK m a -> m b
foldl' :: forall (m :: * -> *) b a.
Monad m =>
(b -> a -> b) -> b -> StreamK m a -> m b
foldl' b -> a -> b
step b
begin = (b -> a -> b) -> b -> (b -> b) -> StreamK m a -> m b
forall (m :: * -> *) a b x.
Monad m =>
(x -> a -> x) -> x -> (x -> b) -> StreamK m a -> m b
foldlx' b -> a -> b
step b
begin b -> b
forall a. a -> a
id

-- XXX replace the recursive "go" with explicit continuations.
-- | Like 'foldx', but with a monadic step function.
{-# INLINABLE foldlMx' #-}
foldlMx' :: Monad m
    => (x -> a -> m x) -> m x -> (x -> m b) -> StreamK m a -> m b
foldlMx' :: forall (m :: * -> *) x a b.
Monad m =>
(x -> a -> m x) -> m x -> (x -> m b) -> StreamK m a -> m b
foldlMx' x -> a -> m x
step m x
begin x -> m b
done = m x -> StreamK m a -> m b
go m x
begin
    where
    go :: m x -> StreamK m a -> m b
go !m x
acc StreamK m a
m1 =
        let stop :: m b
stop = m x
acc m x -> (x -> m b) -> m b
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= x -> m b
done
            single :: a -> m b
single a
a = m x
acc m x -> (x -> m b) -> m b
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= \x
b -> x -> a -> m x
step x
b a
a m x -> (x -> m b) -> m b
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= x -> m b
done
            yieldk :: a -> StreamK m a -> m b
yieldk a
a StreamK m a
r = m x
acc m x -> (x -> m b) -> m b
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= \x
b -> x -> a -> m x
step x
b a
a m x -> (x -> m b) -> m b
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= \x
x -> m x -> StreamK m a -> m b
go (x -> m x
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return x
x) StreamK m a
r
         in State StreamK m a
-> (a -> StreamK m a -> m b)
-> (a -> m b)
-> m b
-> StreamK m a
-> m b
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a. State t m a
defState a -> StreamK m a -> m b
yieldk a -> m b
single m b
stop StreamK m a
m1

-- | Like 'foldl'' but with a monadic step function.
{-# INLINE foldlM' #-}
foldlM' :: Monad m => (b -> a -> m b) -> m b -> StreamK m a -> m b
foldlM' :: forall (m :: * -> *) b a.
Monad m =>
(b -> a -> m b) -> m b -> StreamK m a -> m b
foldlM' b -> a -> m b
step m b
begin = (b -> a -> m b) -> m b -> (b -> m b) -> StreamK m a -> m b
forall (m :: * -> *) x a b.
Monad m =>
(x -> a -> m x) -> m x -> (x -> m b) -> StreamK m a -> m b
foldlMx' b -> a -> m b
step m b
begin b -> m b
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return

------------------------------------------------------------------------------
-- Specialized folds
------------------------------------------------------------------------------

-- XXX use foldrM to implement folds where possible
-- XXX This (commented) definition of drain and mapM_ perform much better on
-- some benchmarks but worse on others. Need to investigate why, may there is
-- an optimization opportunity that we can exploit.
-- drain = foldrM (\_ xs -> return () >> xs) (return ())

--
-- > drain = foldl' (\_ _ -> ()) ()
-- > drain = mapM_ (\_ -> return ())
{-# INLINE drain #-}
drain :: Monad m => StreamK m a -> m ()
drain :: forall (m :: * -> *) a. Monad m => StreamK m a -> m ()
drain = (a -> m () -> m ()) -> m () -> StreamK m a -> m ()
forall a (m :: * -> *) b.
(a -> m b -> m b) -> m b -> StreamK m a -> m b
foldrM (\a
_ m ()
xs -> m ()
xs) (() -> m ()
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return ())
{-
drain = go
    where
    go m1 =
        let stop = return ()
            single _ = return ()
            yieldk _ r = go r
         in foldStream defState yieldk single stop m1
-}

{-# INLINE null #-}
null :: Monad m => StreamK m a -> m Bool
-- null = foldrM (\_ _ -> return True) (return False)
null :: forall (m :: * -> *) a. Monad m => StreamK m a -> m Bool
null StreamK m a
m =
    let stop :: m Bool
stop      = Bool -> m Bool
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
True
        single :: p -> m Bool
single p
_  = Bool -> m Bool
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
False
        yieldk :: p -> p -> m Bool
yieldk p
_ p
_ = Bool -> m Bool
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
False
    in State StreamK m a
-> (a -> StreamK m a -> m Bool)
-> (a -> m Bool)
-> m Bool
-> StreamK m a
-> m Bool
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a. State t m a
defState a -> StreamK m a -> m Bool
forall {m :: * -> *} {p} {p}. Monad m => p -> p -> m Bool
yieldk a -> m Bool
forall {m :: * -> *} {p}. Monad m => p -> m Bool
single m Bool
stop StreamK m a
m

------------------------------------------------------------------------------
-- Semigroup
------------------------------------------------------------------------------

infixr 6 `append`

{-# INLINE append #-}
append :: StreamK m a -> StreamK m a -> StreamK m a
-- XXX This doubles the time of toNullAp benchmark, may not be fusing properly
-- serial xs ys = augmentS (\c n -> foldrS c n xs) ys
append :: forall (m :: * -> *) a. StreamK m a -> StreamK m a -> StreamK m a
append StreamK m a
m1 StreamK m a
m2 = StreamK m a -> StreamK m a
go StreamK m a
m1
    where
    go :: StreamK m a -> StreamK m a
go StreamK m a
m = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
               let stop :: m r
stop       = State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp StreamK m a
m2
                   single :: a -> m r
single a
a   = a -> StreamK m a -> m r
yld a
a StreamK m a
m2
                   yieldk :: a -> StreamK m a -> m r
yieldk a
a StreamK m a
r = a -> StreamK m a -> m r
yld a
a (StreamK m a -> StreamK m a
go StreamK m a
r)
               in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yieldk a -> m r
single m r
stop StreamK m a
m

-- join/merge/append streams depending on consM
{-# INLINE conjoin #-}
conjoin :: Monad m => StreamK m a -> StreamK m a -> StreamK m a
conjoin :: forall (m :: * -> *) a.
Monad m =>
StreamK m a -> StreamK m a -> StreamK m a
conjoin StreamK m a
xs = ((m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
-> StreamK m a -> StreamK m a
forall (m :: * -> *) a.
Monad m =>
((m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
-> StreamK m a -> StreamK m a
augmentSM (\m a -> StreamK m a -> StreamK m a
c StreamK m a
n -> (m a -> StreamK m a -> StreamK m a)
-> StreamK m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) a b.
Monad m =>
(m a -> StreamK m b -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
foldrSM m a -> StreamK m a -> StreamK m a
c StreamK m a
n StreamK m a
xs)

instance Semigroup (StreamK m a) where
    <> :: StreamK m a -> StreamK m a -> StreamK m a
(<>) = StreamK m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) a. StreamK m a -> StreamK m a -> StreamK m a
append

------------------------------------------------------------------------------
-- Monoid
------------------------------------------------------------------------------

instance Monoid (StreamK m a) where
    mempty :: StreamK m a
mempty = StreamK m a
forall (m :: * -> *) a. StreamK m a
nil
    mappend :: StreamK m a -> StreamK m a -> StreamK m a
mappend = StreamK m a -> StreamK m a -> StreamK m a
forall a. Semigroup a => a -> a -> a
(<>)

-------------------------------------------------------------------------------
-- Functor
-------------------------------------------------------------------------------

-- IMPORTANT: This is eta expanded on purpose. This should not be eta
-- reduced. This will cause a lot of regressions, probably because of some
-- rewrite rules. Ideally don't run hlint on this file.
{-# INLINE_LATE mapFB #-}
mapFB :: forall b m a.
       (b -> StreamK m b -> StreamK m b)
    -> (a -> b)
    -> a
    -> StreamK m b
    -> StreamK m b
mapFB :: forall b (m :: * -> *) a.
(b -> StreamK m b -> StreamK m b)
-> (a -> b) -> a -> StreamK m b -> StreamK m b
mapFB b -> StreamK m b -> StreamK m b
c a -> b
f = \a
x StreamK m b
ys -> b -> StreamK m b -> StreamK m b
c (a -> b
f a
x) StreamK m b
ys

{-# RULES
"mapFB/mapFB" forall c f g. mapFB (mapFB c f) g = mapFB c (f . g)
"mapFB/id"    forall c.     mapFB c (\x -> x)   = c
    #-}

{-# INLINE map #-}
map :: (a -> b) -> StreamK m a -> StreamK m b
map :: forall a b (m :: * -> *). (a -> b) -> StreamK m a -> StreamK m b
map a -> b
f StreamK m a
xs = ((b -> StreamK m b -> StreamK m b) -> StreamK m b -> StreamK m b)
-> StreamK m b
forall a (m :: * -> *).
((a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
-> StreamK m a
buildS (\b -> StreamK m b -> StreamK m b
c StreamK m b
n -> (a -> StreamK m b -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
forall a (m :: * -> *) b.
(a -> StreamK m b -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
foldrS ((b -> StreamK m b -> StreamK m b)
-> (a -> b) -> a -> StreamK m b -> StreamK m b
forall b (m :: * -> *) a.
(b -> StreamK m b -> StreamK m b)
-> (a -> b) -> a -> StreamK m b -> StreamK m b
mapFB b -> StreamK m b -> StreamK m b
c a -> b
f) StreamK m b
n StreamK m a
xs)

-- XXX This definition might potentially be more efficient, but the cost in the
-- benchmark is dominated by unfoldrM cost so we cannot correctly determine
-- differences in the mapping cost. We should perhaps deduct the cost of
-- unfoldrM from the benchmarks and then compare.
{-
map f m = go m
    where
        go m1 =
            mkStream $ \st yld sng stp ->
            let single     = sng . f
                yieldk a r = yld (f a) (go r)
            in foldStream (adaptState st) yieldk single stp m1
-}

{-# INLINE_LATE mapMFB #-}
mapMFB :: Monad m => (m b -> t m b -> t m b) -> (a -> m b) -> m a -> t m b -> t m b
mapMFB :: forall (m :: * -> *) b (t :: (* -> *) -> * -> *) a.
Monad m =>
(m b -> t m b -> t m b) -> (a -> m b) -> m a -> t m b -> t m b
mapMFB m b -> t m b -> t m b
c a -> m b
f m a
x = m b -> t m b -> t m b
c (m a
x m a -> (a -> m b) -> m b
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= a -> m b
f)

{-# RULES
    "mapMFB/mapMFB" forall c f g. mapMFB (mapMFB c f) g = mapMFB c (f >=> g)
    #-}
-- XXX These rules may never fire because pure/return type class rules will
-- fire first.
{-
"mapMFB/pure"    forall c.     mapMFB c (\x -> pure x)   = c
"mapMFB/return"  forall c.     mapMFB c (\x -> return x) = c
-}

-- This is experimental serial version supporting fusion.
--
-- XXX what if we do not want to fuse two concurrent mapMs?
-- XXX we can combine two concurrent mapM only if the SVar is of the same type
-- So for now we use it only for serial streams.
-- XXX fusion would be easier for monomoprhic stream types.
-- {-# RULES "mapM serial" mapM = mapMSerial #-}
{-# INLINE mapMSerial #-}
mapMSerial :: Monad m => (a -> m b) -> StreamK m a -> StreamK m b
mapMSerial :: forall (m :: * -> *) a b.
Monad m =>
(a -> m b) -> StreamK m a -> StreamK m b
mapMSerial a -> m b
f StreamK m a
xs = ((m b -> StreamK m b -> StreamK m b) -> StreamK m b -> StreamK m b)
-> StreamK m b
forall (m :: * -> *) a.
Monad m =>
((m a -> StreamK m a -> StreamK m a) -> StreamK m a -> StreamK m a)
-> StreamK m a
buildSM (\m b -> StreamK m b -> StreamK m b
c StreamK m b
n -> (m a -> StreamK m b -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
forall (m :: * -> *) a b.
Monad m =>
(m a -> StreamK m b -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
foldrSMShared ((m b -> StreamK m b -> StreamK m b)
-> (a -> m b) -> m a -> StreamK m b -> StreamK m b
forall (m :: * -> *) b (t :: (* -> *) -> * -> *) a.
Monad m =>
(m b -> t m b -> t m b) -> (a -> m b) -> m a -> t m b -> t m b
mapMFB m b -> StreamK m b -> StreamK m b
c a -> m b
f) StreamK m b
n StreamK m a
xs)

{-# INLINE mapMWith #-}
mapMWith ::
       (m b -> StreamK m b -> StreamK m b)
    -> (a -> m b)
    -> StreamK m a
    -> StreamK m b
mapMWith :: forall (m :: * -> *) b a.
(m b -> StreamK m b -> StreamK m b)
-> (a -> m b) -> StreamK m a -> StreamK m b
mapMWith m b -> StreamK m b -> StreamK m b
cns a -> m b
f = (a -> StreamK m b -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
forall a (m :: * -> *) b.
(a -> StreamK m b -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
foldrSShared (\a
x StreamK m b
xs -> a -> m b
f a
x m b -> StreamK m b -> StreamK m b
`cns` StreamK m b
xs) StreamK m b
forall (m :: * -> *) a. StreamK m a
nil

{-
-- See note under map definition above.
mapMWith cns f = go
    where
    go m1 = mkStream $ \st yld sng stp ->
        let single a  = f a >>= sng
            yieldk a r = foldStreamShared st yld sng stp $ f a `cns` go r
         in foldStream (adaptState st) yieldk single stp m1
-}

-- XXX in fact use the Stream type everywhere and only use polymorphism in the
-- high level modules/prelude.
instance Monad m => Functor (StreamK m) where
    fmap :: forall a b. (a -> b) -> StreamK m a -> StreamK m b
fmap = (a -> b) -> StreamK m a -> StreamK m b
forall a b (m :: * -> *). (a -> b) -> StreamK m a -> StreamK m b
map

------------------------------------------------------------------------------
-- Lists
------------------------------------------------------------------------------

-- Serial streams can act like regular lists using the Identity monad

-- XXX Show instance is 10x slower compared to read, we can do much better.
-- The list show instance itself is really slow.

-- XXX The default definitions of "<" in the Ord instance etc. do not perform
-- well, because they do not get inlined. Need to add INLINE in Ord class in
-- base?

instance IsList (StreamK Identity a) where
    type (Item (StreamK Identity a)) = a

    {-# INLINE fromList #-}
    fromList :: [Item (StreamK Identity a)] -> StreamK Identity a
fromList = [a] -> StreamK Identity a
[Item (StreamK Identity a)] -> StreamK Identity a
forall (f :: * -> *) a (m :: * -> *).
Foldable f =>
f a -> StreamK m a
fromFoldable

    {-# INLINE toList #-}
    toList :: StreamK Identity a -> [Item (StreamK Identity a)]
toList = (a -> [a] -> [a]) -> [a] -> StreamK Identity a -> [a]
forall a b. (a -> b -> b) -> b -> StreamK Identity a -> b
forall (t :: * -> *) a b.
Foldable t =>
(a -> b -> b) -> b -> t a -> b
Data.Foldable.foldr (:) []

-- XXX Fix these
{-
instance Eq a => Eq (StreamK Identity a) where
    {-# INLINE (==) #-}
    (==) xs ys = runIdentity $ eqBy (==) xs ys

instance Ord a => Ord (StreamK Identity a) where
    {-# INLINE compare #-}
    compare xs ys = runIdentity $ cmpBy compare xs ys

    {-# INLINE (<) #-}
    x < y =
        case compare x y of
            LT -> True
            _ -> False

    {-# INLINE (<=) #-}
    x <= y =
        case compare x y of
            GT -> False
            _ -> True

    {-# INLINE (>) #-}
    x > y =
        case compare x y of
            GT -> True
            _ -> False

    {-# INLINE (>=) #-}
    x >= y =
        case compare x y of
            LT -> False
            _ -> True

    {-# INLINE max #-}
    max x y = if x <= y then y else x

    {-# INLINE min #-}
    min x y = if x <= y then x else y
-}

instance Show a => Show (StreamK Identity a) where
    showsPrec :: Int -> StreamK Identity a -> ShowS
showsPrec Int
p StreamK Identity a
dl = Bool -> ShowS -> ShowS
showParen (Int
p Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
> Int
10) (ShowS -> ShowS) -> ShowS -> ShowS
forall a b. (a -> b) -> a -> b
$
        String -> ShowS
showString String
"fromList " ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
. [a] -> ShowS
forall a. Show a => a -> ShowS
shows (StreamK Identity a -> [Item (StreamK Identity a)]
forall l. IsList l => l -> [Item l]
toList StreamK Identity a
dl)

instance Read a => Read (StreamK Identity a) where
    readPrec :: ReadPrec (StreamK Identity a)
readPrec = ReadPrec (StreamK Identity a) -> ReadPrec (StreamK Identity a)
forall a. ReadPrec a -> ReadPrec a
parens (ReadPrec (StreamK Identity a) -> ReadPrec (StreamK Identity a))
-> ReadPrec (StreamK Identity a) -> ReadPrec (StreamK Identity a)
forall a b. (a -> b) -> a -> b
$ Int
-> ReadPrec (StreamK Identity a) -> ReadPrec (StreamK Identity a)
forall a. Int -> ReadPrec a -> ReadPrec a
prec Int
10 (ReadPrec (StreamK Identity a) -> ReadPrec (StreamK Identity a))
-> ReadPrec (StreamK Identity a) -> ReadPrec (StreamK Identity a)
forall a b. (a -> b) -> a -> b
$ do
        Ident String
"fromList" <- ReadPrec Lexeme
lexP
        [a] -> StreamK Identity a
[Item (StreamK Identity a)] -> StreamK Identity a
forall l. IsList l => [Item l] -> l
fromList ([a] -> StreamK Identity a)
-> ReadPrec [a] -> ReadPrec (StreamK Identity a)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> ReadPrec [a]
forall a. Read a => ReadPrec a
readPrec

    readListPrec :: ReadPrec [StreamK Identity a]
readListPrec = ReadPrec [StreamK Identity a]
forall a. Read a => ReadPrec [a]
readListPrecDefault

instance (a ~ Char) => IsString (StreamK Identity a) where
    {-# INLINE fromString #-}
    fromString :: String -> StreamK Identity a
fromString = String -> StreamK Identity a
[Item (StreamK Identity a)] -> StreamK Identity a
forall l. IsList l => [Item l] -> l
fromList

-------------------------------------------------------------------------------
-- Foldable
-------------------------------------------------------------------------------

-- | Lazy right associative fold.
{-# INLINE foldr #-}
foldr :: Monad m => (a -> b -> b) -> b -> StreamK m a -> m b
foldr :: forall (m :: * -> *) a b.
Monad m =>
(a -> b -> b) -> b -> StreamK m a -> m b
foldr a -> b -> b
step b
acc = (a -> m b -> m b) -> m b -> StreamK m a -> m b
forall a (m :: * -> *) b.
(a -> m b -> m b) -> m b -> StreamK m a -> m b
foldrM (\a
x m b
xs -> m b
xs m b -> (b -> m b) -> m b
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= \b
b -> b -> m b
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return (a -> b -> b
step a
x b
b)) (b -> m b
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return b
acc)

-- The default Foldable instance has several issues:
-- 1) several definitions do not have INLINE on them, so we provide
--    re-implementations with INLINE pragmas.
-- 2) the definitions of sum/product/maximum/minimum are inefficient as they
--    use right folds, they cannot run in constant memory. We provide
--    implementations using strict left folds here.

instance (Foldable m, Monad m) => Foldable (StreamK m) where

    {-# INLINE foldMap #-}
    foldMap :: forall m a. Monoid m => (a -> m) -> StreamK m a -> m
foldMap a -> m
f =
          m m -> m
forall m. Monoid m => m m -> m
forall (t :: * -> *) m. (Foldable t, Monoid m) => t m -> m
fold
        (m m -> m) -> (StreamK m a -> m m) -> StreamK m a -> m
forall b c a. (b -> c) -> (a -> b) -> a -> c
. (a -> m -> m) -> m -> StreamK m a -> m m
forall (m :: * -> *) a b.
Monad m =>
(a -> b -> b) -> b -> StreamK m a -> m b
Streamly.Internal.Data.StreamK.Type.foldr (m -> m -> m
forall a. Monoid a => a -> a -> a
mappend (m -> m -> m) -> (a -> m) -> a -> m -> m
forall b c a. (b -> c) -> (a -> b) -> a -> c
. a -> m
f) m
forall a. Monoid a => a
mempty

    {-# INLINE foldr #-}
    foldr :: forall a b. (a -> b -> b) -> b -> StreamK m a -> b
foldr a -> b -> b
f b
z StreamK m a
t = Endo b -> b -> b
forall a. Endo a -> a -> a
appEndo ((a -> Endo b) -> StreamK m a -> Endo b
forall m a. Monoid m => (a -> m) -> StreamK m a -> m
forall (t :: * -> *) m a.
(Foldable t, Monoid m) =>
(a -> m) -> t a -> m
foldMap ((b -> b) -> Endo b
forall a. (a -> a) -> Endo a
Endo ((b -> b) -> Endo b) -> (a -> b -> b) -> a -> Endo b
forall b c a. Coercible b c => (b -> c) -> (a -> b) -> a -> c
#. a -> b -> b
f) StreamK m a
t) b
z

    {-# INLINE foldl' #-}
    foldl' :: forall b a. (b -> a -> b) -> b -> StreamK m a -> b
foldl' b -> a -> b
f b
z0 StreamK m a
xs = (a -> (b -> b) -> b -> b) -> (b -> b) -> StreamK m a -> b -> b
forall a b. (a -> b -> b) -> b -> StreamK m a -> b
forall (t :: * -> *) a b.
Foldable t =>
(a -> b -> b) -> b -> t a -> b
Data.Foldable.foldr a -> (b -> b) -> b -> b
forall {b}. a -> (b -> b) -> b -> b
f' b -> b
forall a. a -> a
id StreamK m a
xs b
z0
        where f' :: a -> (b -> b) -> b -> b
f' a
x b -> b
k = (b -> b) -> b -> b
forall a b. (a -> b) -> a -> b
oneShot ((b -> b) -> b -> b) -> (b -> b) -> b -> b
forall a b. (a -> b) -> a -> b
$ \b
z -> b -> b
k (b -> b) -> b -> b
forall a b. (a -> b) -> a -> b
$! b -> a -> b
f b
z a
x

    {-# INLINE length #-}
    length :: forall a. StreamK m a -> Int
length = (Int -> a -> Int) -> Int -> StreamK m a -> Int
forall b a. (b -> a -> b) -> b -> StreamK m a -> b
forall (t :: * -> *) b a.
Foldable t =>
(b -> a -> b) -> b -> t a -> b
Data.Foldable.foldl' (\Int
n a
_ -> Int
n Int -> Int -> Int
forall a. Num a => a -> a -> a
+ Int
1) Int
0

    {-# INLINE elem #-}
    elem :: forall a. Eq a => a -> StreamK m a -> Bool
elem = (a -> Bool) -> StreamK m a -> Bool
forall (t :: * -> *) a. Foldable t => (a -> Bool) -> t a -> Bool
any ((a -> Bool) -> StreamK m a -> Bool)
-> (a -> a -> Bool) -> a -> StreamK m a -> Bool
forall b c a. (b -> c) -> (a -> b) -> a -> c
. a -> a -> Bool
forall a. Eq a => a -> a -> Bool
(==)

    {-# INLINE maximum #-}
    maximum :: forall a. Ord a => StreamK m a -> a
maximum =
          a -> Maybe a -> a
forall a. a -> Maybe a -> a
fromMaybe (String -> a
forall a. String -> a
errorWithoutStackTrace String
"maximum: empty stream")
        (Maybe a -> a) -> (StreamK m a -> Maybe a) -> StreamK m a -> a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Maybe' a -> Maybe a
forall a. Maybe' a -> Maybe a
toMaybe
        (Maybe' a -> Maybe a)
-> (StreamK m a -> Maybe' a) -> StreamK m a -> Maybe a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. (Maybe' a -> a -> Maybe' a) -> Maybe' a -> StreamK m a -> Maybe' a
forall b a. (b -> a -> b) -> b -> StreamK m a -> b
forall (t :: * -> *) b a.
Foldable t =>
(b -> a -> b) -> b -> t a -> b
Data.Foldable.foldl' Maybe' a -> a -> Maybe' a
forall {a}. Ord a => Maybe' a -> a -> Maybe' a
getMax Maybe' a
forall a. Maybe' a
Nothing'

        where

        getMax :: Maybe' a -> a -> Maybe' a
getMax Maybe' a
Nothing' a
x = a -> Maybe' a
forall a. a -> Maybe' a
Just' a
x
        getMax (Just' a
mx) a
x = a -> Maybe' a
forall a. a -> Maybe' a
Just' (a -> Maybe' a) -> a -> Maybe' a
forall a b. (a -> b) -> a -> b
$! a -> a -> a
forall a. Ord a => a -> a -> a
max a
mx a
x

    {-# INLINE minimum #-}
    minimum :: forall a. Ord a => StreamK m a -> a
minimum =
          a -> Maybe a -> a
forall a. a -> Maybe a -> a
fromMaybe (String -> a
forall a. String -> a
errorWithoutStackTrace String
"minimum: empty stream")
        (Maybe a -> a) -> (StreamK m a -> Maybe a) -> StreamK m a -> a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Maybe' a -> Maybe a
forall a. Maybe' a -> Maybe a
toMaybe
        (Maybe' a -> Maybe a)
-> (StreamK m a -> Maybe' a) -> StreamK m a -> Maybe a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. (Maybe' a -> a -> Maybe' a) -> Maybe' a -> StreamK m a -> Maybe' a
forall b a. (b -> a -> b) -> b -> StreamK m a -> b
forall (t :: * -> *) b a.
Foldable t =>
(b -> a -> b) -> b -> t a -> b
Data.Foldable.foldl' Maybe' a -> a -> Maybe' a
forall {a}. Ord a => Maybe' a -> a -> Maybe' a
getMin Maybe' a
forall a. Maybe' a
Nothing'

        where

        getMin :: Maybe' a -> a -> Maybe' a
getMin Maybe' a
Nothing' a
x = a -> Maybe' a
forall a. a -> Maybe' a
Just' a
x
        getMin (Just' a
mn) a
x = a -> Maybe' a
forall a. a -> Maybe' a
Just' (a -> Maybe' a) -> a -> Maybe' a
forall a b. (a -> b) -> a -> b
$! a -> a -> a
forall a. Ord a => a -> a -> a
min a
mn a
x

    {-# INLINE sum #-}
    sum :: forall a. Num a => StreamK m a -> a
sum = (a -> a -> a) -> a -> StreamK m a -> a
forall b a. (b -> a -> b) -> b -> StreamK m a -> b
forall (t :: * -> *) b a.
Foldable t =>
(b -> a -> b) -> b -> t a -> b
Data.Foldable.foldl' a -> a -> a
forall a. Num a => a -> a -> a
(+) a
0

    {-# INLINE product #-}
    product :: forall a. Num a => StreamK m a -> a
product = (a -> a -> a) -> a -> StreamK m a -> a
forall b a. (b -> a -> b) -> b -> StreamK m a -> b
forall (t :: * -> *) b a.
Foldable t =>
(b -> a -> b) -> b -> t a -> b
Data.Foldable.foldl' a -> a -> a
forall a. Num a => a -> a -> a
(*) a
1

-------------------------------------------------------------------------------
-- Traversable
-------------------------------------------------------------------------------

instance Traversable (StreamK Identity) where
    {-# INLINE traverse #-}
    traverse :: forall (f :: * -> *) a b.
Applicative f =>
(a -> f b) -> StreamK Identity a -> f (StreamK Identity b)
traverse a -> f b
f StreamK Identity a
xs =
        Identity (f (StreamK Identity b)) -> f (StreamK Identity b)
forall a. Identity a -> a
runIdentity
            (Identity (f (StreamK Identity b)) -> f (StreamK Identity b))
-> Identity (f (StreamK Identity b)) -> f (StreamK Identity b)
forall a b. (a -> b) -> a -> b
$ (a -> f (StreamK Identity b) -> f (StreamK Identity b))
-> f (StreamK Identity b)
-> StreamK Identity a
-> Identity (f (StreamK Identity b))
forall (m :: * -> *) a b.
Monad m =>
(a -> b -> b) -> b -> StreamK m a -> m b
Streamly.Internal.Data.StreamK.Type.foldr
                a -> f (StreamK Identity b) -> f (StreamK Identity b)
forall {m :: * -> *}. a -> f (StreamK m b) -> f (StreamK m b)
consA (StreamK Identity b -> f (StreamK Identity b)
forall a. a -> f a
forall (f :: * -> *) a. Applicative f => a -> f a
pure StreamK Identity b
forall a. Monoid a => a
mempty) StreamK Identity a
xs

        where

        consA :: a -> f (StreamK m b) -> f (StreamK m b)
consA a
x f (StreamK m b)
ys = (b -> StreamK m b -> StreamK m b)
-> f b -> f (StreamK m b) -> f (StreamK m b)
forall a b c. (a -> b -> c) -> f a -> f b -> f c
forall (f :: * -> *) a b c.
Applicative f =>
(a -> b -> c) -> f a -> f b -> f c
liftA2 b -> StreamK m b -> StreamK m b
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
cons (a -> f b
f a
x) f (StreamK m b)
ys

-------------------------------------------------------------------------------
-- Nesting
-------------------------------------------------------------------------------

-- | Detach a stream from an SVar
{-# INLINE unShare #-}
unShare :: StreamK m a -> StreamK m a
unShare :: forall (m :: * -> *) a. StreamK m a -> StreamK m a
unShare StreamK m a
x = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
    State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp StreamK m a
x

-- XXX the function stream and value stream can run in parallel
{-# INLINE crossApplyWith #-}
crossApplyWith ::
       (StreamK m b -> StreamK m b -> StreamK m b)
    -> StreamK m (a -> b)
    -> StreamK m a
    -> StreamK m b
crossApplyWith :: forall (m :: * -> *) b a.
(StreamK m b -> StreamK m b -> StreamK m b)
-> StreamK m (a -> b) -> StreamK m a -> StreamK m b
crossApplyWith StreamK m b -> StreamK m b -> StreamK m b
par StreamK m (a -> b)
fstream StreamK m a
stream = StreamK m (a -> b) -> StreamK m b
go1 StreamK m (a -> b)
fstream

    where

    go1 :: StreamK m (a -> b) -> StreamK m b
go1 StreamK m (a -> b)
m =
        (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m b
  -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
 -> StreamK m b)
-> (forall r.
    State StreamK m b
    -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall a b. (a -> b) -> a -> b
$ \State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp ->
            let foldShared :: StreamK m b -> m r
foldShared = State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp
                single :: (a -> b) -> m r
single a -> b
f   = StreamK m b -> m r
foldShared (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m b -> StreamK m b
forall (m :: * -> *) a. StreamK m a -> StreamK m a
unShare ((a -> b) -> StreamK m a -> StreamK m b
forall a b (m :: * -> *). (a -> b) -> StreamK m a -> StreamK m b
go2 a -> b
f StreamK m a
stream)
                yieldk :: (a -> b) -> StreamK m (a -> b) -> m r
yieldk a -> b
f StreamK m (a -> b)
r = StreamK m b -> m r
foldShared (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m b -> StreamK m b
forall (m :: * -> *) a. StreamK m a -> StreamK m a
unShare ((a -> b) -> StreamK m a -> StreamK m b
forall a b (m :: * -> *). (a -> b) -> StreamK m a -> StreamK m b
go2 a -> b
f StreamK m a
stream) StreamK m b -> StreamK m b -> StreamK m b
`par` StreamK m (a -> b) -> StreamK m b
go1 StreamK m (a -> b)
r
            in State StreamK m (a -> b)
-> ((a -> b) -> StreamK m (a -> b) -> m r)
-> ((a -> b) -> m r)
-> m r
-> StreamK m (a -> b)
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m b -> State StreamK m (a -> b)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m b
st) (a -> b) -> StreamK m (a -> b) -> m r
yieldk (a -> b) -> m r
single m r
stp StreamK m (a -> b)
m

    go2 :: (t -> a) -> StreamK m t -> StreamK m a
go2 t -> a
f StreamK m t
m =
        (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
            let single :: t -> m r
single t
a   = a -> m r
sng (t -> a
f t
a)
                yieldk :: t -> StreamK m t -> m r
yieldk t
a StreamK m t
r = a -> StreamK m a -> m r
yld (t -> a
f t
a) ((t -> a) -> StreamK m t -> StreamK m a
go2 t -> a
f StreamK m t
r)
            in State StreamK m t
-> (t -> StreamK m t -> m r)
-> (t -> m r)
-> m r
-> StreamK m t
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m a -> State StreamK m t
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m a
st) t -> StreamK m t -> m r
yieldk t -> m r
single m r
stp StreamK m t
m

-- | Apply a stream of functions to a stream of values and flatten the results.
--
-- Note that the second stream is evaluated multiple times.
--
-- Definition:
--
-- >>> crossApply = StreamK.crossApplyWith StreamK.append
-- >>> crossApply = Stream.crossWith id
--
{-# INLINE crossApply #-}
crossApply ::
       StreamK m (a -> b)
    -> StreamK m a
    -> StreamK m b
crossApply :: forall (m :: * -> *) a b.
StreamK m (a -> b) -> StreamK m a -> StreamK m b
crossApply StreamK m (a -> b)
fstream StreamK m a
stream = StreamK m (a -> b) -> StreamK m b
forall {a}. StreamK m (a -> a) -> StreamK m a
go1 StreamK m (a -> b)
fstream

    where

    go1 :: StreamK m (a -> a) -> StreamK m a
go1 StreamK m (a -> a)
m =
        (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
            let foldShared :: StreamK m a -> m r
foldShared = State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp
                single :: (a -> a) -> m r
single a -> a
f   = StreamK m a -> m r
foldShared (StreamK m a -> m r) -> StreamK m a -> m r
forall a b. (a -> b) -> a -> b
$ (a -> a) -> StreamK m a -> StreamK m a
forall a b (m :: * -> *). (a -> b) -> StreamK m a -> StreamK m b
go3 a -> a
f StreamK m a
stream
                yieldk :: (a -> a) -> StreamK m (a -> a) -> m r
yieldk a -> a
f StreamK m (a -> a)
r = StreamK m a -> m r
foldShared (StreamK m a -> m r) -> StreamK m a -> m r
forall a b. (a -> b) -> a -> b
$ (a -> a) -> StreamK m (a -> a) -> StreamK m a -> StreamK m a
go2 a -> a
f StreamK m (a -> a)
r StreamK m a
stream
            in State StreamK m (a -> a)
-> ((a -> a) -> StreamK m (a -> a) -> m r)
-> ((a -> a) -> m r)
-> m r
-> StreamK m (a -> a)
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m a -> State StreamK m (a -> a)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m a
st) (a -> a) -> StreamK m (a -> a) -> m r
yieldk (a -> a) -> m r
single m r
stp StreamK m (a -> a)
m

    go2 :: (a -> a) -> StreamK m (a -> a) -> StreamK m a -> StreamK m a
go2 a -> a
f StreamK m (a -> a)
r1 StreamK m a
m =
        (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
            let foldShared :: StreamK m a -> m r
foldShared = State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp
                stop :: m r
stop = StreamK m a -> m r
foldShared (StreamK m a -> m r) -> StreamK m a -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m (a -> a) -> StreamK m a
go1 StreamK m (a -> a)
r1
                single :: a -> m r
single a
a   = a -> StreamK m a -> m r
yld (a -> a
f a
a) (StreamK m (a -> a) -> StreamK m a
go1 StreamK m (a -> a)
r1)
                yieldk :: a -> StreamK m a -> m r
yieldk a
a StreamK m a
r = a -> StreamK m a -> m r
yld (a -> a
f a
a) ((a -> a) -> StreamK m (a -> a) -> StreamK m a -> StreamK m a
go2 a -> a
f StreamK m (a -> a)
r1 StreamK m a
r)
            in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m a -> State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m a
st) a -> StreamK m a -> m r
yieldk a -> m r
single m r
stop StreamK m a
m

    go3 :: (t -> a) -> StreamK m t -> StreamK m a
go3 t -> a
f StreamK m t
m =
        (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
            let single :: t -> m r
single t
a   = a -> m r
sng (t -> a
f t
a)
                yieldk :: t -> StreamK m t -> m r
yieldk t
a StreamK m t
r = a -> StreamK m a -> m r
yld (t -> a
f t
a) ((t -> a) -> StreamK m t -> StreamK m a
go3 t -> a
f StreamK m t
r)
            in State StreamK m t
-> (t -> StreamK m t -> m r)
-> (t -> m r)
-> m r
-> StreamK m t
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m a -> State StreamK m t
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m a
st) t -> StreamK m t -> m r
yieldk t -> m r
single m r
stp StreamK m t
m

{-# INLINE crossApplySnd #-}
crossApplySnd ::
       StreamK m a
    -> StreamK m b
    -> StreamK m b
crossApplySnd :: forall (m :: * -> *) a b. StreamK m a -> StreamK m b -> StreamK m b
crossApplySnd StreamK m a
fstream StreamK m b
stream = StreamK m a -> StreamK m b
forall {a}. StreamK m a -> StreamK m b
go1 StreamK m a
fstream

    where

    go1 :: StreamK m a -> StreamK m b
go1 StreamK m a
m =
        (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m b
  -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
 -> StreamK m b)
-> (forall r.
    State StreamK m b
    -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall a b. (a -> b) -> a -> b
$ \State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp ->
            let foldShared :: StreamK m b -> m r
foldShared = State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp
                single :: p -> m r
single p
_   = StreamK m b -> m r
foldShared StreamK m b
stream
                yieldk :: p -> StreamK m a -> m r
yieldk p
_ StreamK m a
r = StreamK m b -> m r
foldShared (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m a -> StreamK m b -> StreamK m b
go2 StreamK m a
r StreamK m b
stream
            in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m b -> State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m b
st) a -> StreamK m a -> m r
forall {p}. p -> StreamK m a -> m r
yieldk a -> m r
forall {p}. p -> m r
single m r
stp StreamK m a
m

    go2 :: StreamK m a -> StreamK m b -> StreamK m b
go2 StreamK m a
r1 StreamK m b
m =
        (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m b
  -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
 -> StreamK m b)
-> (forall r.
    State StreamK m b
    -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall a b. (a -> b) -> a -> b
$ \State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp ->
            let foldShared :: StreamK m b -> m r
foldShared = State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp
                stop :: m r
stop = StreamK m b -> m r
foldShared (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m a -> StreamK m b
go1 StreamK m a
r1
                single :: b -> m r
single b
a   = b -> StreamK m b -> m r
yld b
a (StreamK m a -> StreamK m b
go1 StreamK m a
r1)
                yieldk :: b -> StreamK m b -> m r
yieldk b
a StreamK m b
r = b -> StreamK m b -> m r
yld b
a (StreamK m a -> StreamK m b -> StreamK m b
go2 StreamK m a
r1 StreamK m b
r)
            in State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m b
st b -> StreamK m b -> m r
yieldk b -> m r
single m r
stop StreamK m b
m

{-# INLINE crossApplyFst #-}
crossApplyFst ::
       StreamK m a
    -> StreamK m b
    -> StreamK m a
crossApplyFst :: forall (m :: * -> *) a b. StreamK m a -> StreamK m b -> StreamK m a
crossApplyFst StreamK m a
fstream StreamK m b
stream = StreamK m a -> StreamK m a
forall {a}. StreamK m a -> StreamK m a
go1 StreamK m a
fstream

    where

    go1 :: StreamK m a -> StreamK m a
go1 StreamK m a
m =
        (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
            let foldShared :: StreamK m a -> m r
foldShared = State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp
                single :: a -> m r
single a
f   = StreamK m a -> m r
foldShared (StreamK m a -> m r) -> StreamK m a -> m r
forall a b. (a -> b) -> a -> b
$ a -> StreamK m b -> StreamK m a
forall {a} {m :: * -> *} {a}. a -> StreamK m a -> StreamK m a
go3 a
f StreamK m b
stream
                yieldk :: a -> StreamK m a -> m r
yieldk a
f StreamK m a
r = StreamK m a -> m r
foldShared (StreamK m a -> m r) -> StreamK m a -> m r
forall a b. (a -> b) -> a -> b
$ a -> StreamK m a -> StreamK m b -> StreamK m a
go2 a
f StreamK m a
r StreamK m b
stream
            in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yieldk a -> m r
single m r
stp StreamK m a
m

    go2 :: a -> StreamK m a -> StreamK m b -> StreamK m a
go2 a
f StreamK m a
r1 StreamK m b
m =
        (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
            let foldShared :: StreamK m a -> m r
foldShared = State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp
                stop :: m r
stop = StreamK m a -> m r
foldShared (StreamK m a -> m r) -> StreamK m a -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m a -> StreamK m a
go1 StreamK m a
r1
                single :: p -> m r
single p
_   = a -> StreamK m a -> m r
yld a
f (StreamK m a -> StreamK m a
go1 StreamK m a
r1)
                yieldk :: p -> StreamK m b -> m r
yieldk p
_ StreamK m b
r = a -> StreamK m a -> m r
yld a
f (a -> StreamK m a -> StreamK m b -> StreamK m a
go2 a
f StreamK m a
r1 StreamK m b
r)
            in State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m a -> State StreamK m b
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m a
st) b -> StreamK m b -> m r
forall {p}. p -> StreamK m b -> m r
yieldk b -> m r
forall {p}. p -> m r
single m r
stop StreamK m b
m

    go3 :: a -> StreamK m a -> StreamK m a
go3 a
f StreamK m a
m =
        (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
            let single :: p -> m r
single p
_   = a -> m r
sng a
f
                yieldk :: p -> StreamK m a -> m r
yieldk p
_ StreamK m a
r = a -> StreamK m a -> m r
yld a
f (a -> StreamK m a -> StreamK m a
go3 a
f StreamK m a
r)
            in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m a -> State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m a
st) a -> StreamK m a -> m r
forall {p}. p -> StreamK m a -> m r
yieldk a -> m r
forall {p}. p -> m r
single m r
stp StreamK m a
m

-- |
-- Definition:
--
-- >>> crossWith f m1 m2 = fmap f m1 `StreamK.crossApply` m2
--
-- Note that the second stream is evaluated multiple times.
--
{-# INLINE crossWith #-}
crossWith :: Monad m => (a -> b -> c) -> StreamK m a -> StreamK m b -> StreamK m c
crossWith :: forall (m :: * -> *) a b c.
Monad m =>
(a -> b -> c) -> StreamK m a -> StreamK m b -> StreamK m c
crossWith a -> b -> c
f StreamK m a
m1 StreamK m b
m2 = (a -> b -> c) -> StreamK m a -> StreamK m (b -> c)
forall a b. (a -> b) -> StreamK m a -> StreamK m b
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap a -> b -> c
f StreamK m a
m1 StreamK m (b -> c) -> StreamK m b -> StreamK m c
forall (m :: * -> *) a b.
StreamK m (a -> b) -> StreamK m a -> StreamK m b
`crossApply` StreamK m b
m2

-- | Given a @StreamK m a@ and @StreamK m b@ generate a stream with all possible
-- combinations of the tuple @(a, b)@.
--
-- Definition:
--
-- >>> cross = StreamK.crossWith (,)
--
-- The second stream is evaluated multiple times. If that is not desired it can
-- be cached in an 'Data.Array.Array' and then generated from the array before
-- calling this function. Caching may also improve performance if the stream is
-- expensive to evaluate.
--
-- See 'Streamly.Internal.Data.Unfold.cross' for a much faster fused
-- alternative.
--
-- Time: O(m x n)
--
-- /Pre-release/
{-# INLINE cross #-}
cross :: Monad m => StreamK m a -> StreamK m b -> StreamK m (a, b)
cross :: forall (m :: * -> *) a b.
Monad m =>
StreamK m a -> StreamK m b -> StreamK m (a, b)
cross = (a -> b -> (a, b))
-> StreamK m a -> StreamK m b -> StreamK m (a, b)
forall (m :: * -> *) a b c.
Monad m =>
(a -> b -> c) -> StreamK m a -> StreamK m b -> StreamK m c
crossWith (,)

-- XXX This is just concatMapWith with arguments flipped. We need to keep this
-- instead of using a concatMap style definition because the bind
-- implementation in Async and WAsync streams show significant perf degradation
-- if the argument order is changed.
{-# INLINE bindWith #-}
bindWith ::
       (StreamK m b -> StreamK m b -> StreamK m b)
    -> StreamK m a
    -> (a -> StreamK m b)
    -> StreamK m b
bindWith :: forall (m :: * -> *) b a.
(StreamK m b -> StreamK m b -> StreamK m b)
-> StreamK m a -> (a -> StreamK m b) -> StreamK m b
bindWith StreamK m b -> StreamK m b -> StreamK m b
par StreamK m a
m1 a -> StreamK m b
f = StreamK m a -> StreamK m b
go StreamK m a
m1
    where
        go :: StreamK m a -> StreamK m b
go StreamK m a
m =
            (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m b
  -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
 -> StreamK m b)
-> (forall r.
    State StreamK m b
    -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall a b. (a -> b) -> a -> b
$ \State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp ->
                let foldShared :: StreamK m b -> m r
foldShared = State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp
                    single :: a -> m r
single a
a   = StreamK m b -> m r
foldShared (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m b -> StreamK m b
forall (m :: * -> *) a. StreamK m a -> StreamK m a
unShare (a -> StreamK m b
f a
a)
                    yieldk :: a -> StreamK m a -> m r
yieldk a
a StreamK m a
r = StreamK m b -> m r
foldShared (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m b -> StreamK m b
forall (m :: * -> *) a. StreamK m a -> StreamK m a
unShare (a -> StreamK m b
f a
a) StreamK m b -> StreamK m b -> StreamK m b
`par` StreamK m a -> StreamK m b
go StreamK m a
r
                in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m b -> State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m b
st) a -> StreamK m a -> m r
yieldk a -> m r
single m r
stp StreamK m a
m

-- XXX express in terms of foldrS?
-- XXX can we use a different stream type for the generated stream being
-- falttened so that we can combine them differently and keep the resulting
-- stream different?
-- XXX do we need specialize to IO?
-- XXX can we optimize when c and a are same, by removing the forall using
-- rewrite rules with type applications?

-- | Perform a 'concatMap' using a specified concat strategy. The first
-- argument specifies a merge or concat function that is used to merge the
-- streams generated by the map function.
--
{-# INLINE concatMapWith #-}
concatMapWith
    ::
       (StreamK m b -> StreamK m b -> StreamK m b)
    -> (a -> StreamK m b)
    -> StreamK m a
    -> StreamK m b
concatMapWith :: forall (m :: * -> *) b a.
(StreamK m b -> StreamK m b -> StreamK m b)
-> (a -> StreamK m b) -> StreamK m a -> StreamK m b
concatMapWith StreamK m b -> StreamK m b -> StreamK m b
par a -> StreamK m b
f StreamK m a
xs = (StreamK m b -> StreamK m b -> StreamK m b)
-> StreamK m a -> (a -> StreamK m b) -> StreamK m b
forall (m :: * -> *) b a.
(StreamK m b -> StreamK m b -> StreamK m b)
-> StreamK m a -> (a -> StreamK m b) -> StreamK m b
bindWith StreamK m b -> StreamK m b -> StreamK m b
par StreamK m a
xs a -> StreamK m b
f

{-# INLINE concatMap #-}
concatMap :: (a -> StreamK m b) -> StreamK m a -> StreamK m b
concatMap :: forall a (m :: * -> *) b.
(a -> StreamK m b) -> StreamK m a -> StreamK m b
concatMap = (StreamK m b -> StreamK m b -> StreamK m b)
-> (a -> StreamK m b) -> StreamK m a -> StreamK m b
forall (m :: * -> *) b a.
(StreamK m b -> StreamK m b -> StreamK m b)
-> (a -> StreamK m b) -> StreamK m a -> StreamK m b
concatMapWith StreamK m b -> StreamK m b -> StreamK m b
forall (m :: * -> *) a. StreamK m a -> StreamK m a -> StreamK m a
append

{-
-- Fused version.
-- XXX This fuses but when the stream is nil this performs poorly.
-- The filterAllOut benchmark degrades. Need to investigate and fix that.
{-# INLINE concatMap #-}
concatMap :: IsStream t => (a -> t m b) -> t m a -> t m b
concatMap f xs = buildS
    (\c n -> foldrS (\x b -> foldrS c b (f x)) n xs)

-- Stream polymorphic concatMap implementation
-- XXX need to use buildSM/foldrSMShared for parallel behavior
-- XXX unShare seems to degrade the fused performance
{-# INLINE_EARLY concatMap_ #-}
concatMap_ :: IsStream t => (a -> t m b) -> t m a -> t m b
concatMap_ f xs = buildS
     (\c n -> foldrSShared (\x b -> foldrSShared c b (unShare $ f x)) n xs)
-}

-- | Combine streams in pairs using a binary combinator, the resulting streams
-- are then combined again in pairs recursively until we get to a single
-- combined stream. The composition would thus form a binary tree.
--
-- For example, you can sort a stream using merge sort like this:
--
-- >>> s = StreamK.fromStream $ Stream.fromList [5,1,7,9,2]
-- >>> generate = StreamK.fromPure
-- >>> combine = StreamK.mergeBy compare
-- >>> Stream.fold Fold.toList $ StreamK.toStream $ StreamK.mergeMapWith combine generate s
-- [1,2,5,7,9]
--
-- Note that if the stream length is not a power of 2, the binary tree composed
-- by mergeMapWith would not be balanced, which may or may not be important
-- depending on what you are trying to achieve.
--
-- /Caution: the stream of streams must be finite/
--
-- /Pre-release/
--
{-# INLINE mergeMapWith #-}
mergeMapWith
    ::
       (StreamK m b -> StreamK m b -> StreamK m b)
    -> (a -> StreamK m b)
    -> StreamK m a
    -> StreamK m b
mergeMapWith :: forall (m :: * -> *) b a.
(StreamK m b -> StreamK m b -> StreamK m b)
-> (a -> StreamK m b) -> StreamK m a -> StreamK m b
mergeMapWith StreamK m b -> StreamK m b -> StreamK m b
combine a -> StreamK m b
f StreamK m a
str = StreamK m (StreamK m b) -> StreamK m b
go (StreamK m a -> StreamK m (StreamK m b)
forall {m :: * -> *}. StreamK m a -> StreamK m (StreamK m b)
leafPairs StreamK m a
str)

    where

    go :: StreamK m (StreamK m b) -> StreamK m b
go StreamK m (StreamK m b)
stream =
        (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m b
  -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
 -> StreamK m b)
-> (forall r.
    State StreamK m b
    -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall a b. (a -> b) -> a -> b
$ \State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp ->
            let foldShared :: StreamK m b -> m r
foldShared = State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp
                single :: StreamK m b -> m r
single StreamK m b
a   = StreamK m b -> m r
foldShared (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m b -> StreamK m b
forall (m :: * -> *) a. StreamK m a -> StreamK m a
unShare StreamK m b
a
                yieldk :: StreamK m b -> StreamK m (StreamK m b) -> m r
yieldk StreamK m b
a StreamK m (StreamK m b)
r = StreamK m b -> m r
foldShared (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m b -> StreamK m (StreamK m b) -> StreamK m b
go1 StreamK m b
a StreamK m (StreamK m b)
r
            in State StreamK m (StreamK m b)
-> (StreamK m b -> StreamK m (StreamK m b) -> m r)
-> (StreamK m b -> m r)
-> m r
-> StreamK m (StreamK m b)
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m b -> State StreamK m (StreamK m b)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m b
st) StreamK m b -> StreamK m (StreamK m b) -> m r
yieldk StreamK m b -> m r
single m r
stp StreamK m (StreamK m b)
stream

    go1 :: StreamK m b -> StreamK m (StreamK m b) -> StreamK m b
go1 StreamK m b
a1 StreamK m (StreamK m b)
stream =
        (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m b
  -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
 -> StreamK m b)
-> (forall r.
    State StreamK m b
    -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall a b. (a -> b) -> a -> b
$ \State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp ->
            let foldShared :: StreamK m b -> m r
foldShared = State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp
                stop :: m r
stop = StreamK m b -> m r
foldShared (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m b -> StreamK m b
forall (m :: * -> *) a. StreamK m a -> StreamK m a
unShare StreamK m b
a1
                single :: StreamK m b -> m r
single StreamK m b
a = StreamK m b -> m r
foldShared (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m b -> StreamK m b
forall (m :: * -> *) a. StreamK m a -> StreamK m a
unShare StreamK m b
a1 StreamK m b -> StreamK m b -> StreamK m b
`combine` StreamK m b
a
                yieldk :: StreamK m b -> StreamK m (StreamK m b) -> m r
yieldk StreamK m b
a StreamK m (StreamK m b)
r =
                    StreamK m b -> m r
foldShared (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m (StreamK m b) -> StreamK m b
go (StreamK m (StreamK m b) -> StreamK m b)
-> StreamK m (StreamK m b) -> StreamK m b
forall a b. (a -> b) -> a -> b
$ StreamK m b -> StreamK m b -> StreamK m b
combine StreamK m b
a1 StreamK m b
a StreamK m b -> StreamK m (StreamK m b) -> StreamK m (StreamK m b)
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
`cons` StreamK m (StreamK m b) -> StreamK m (StreamK m b)
forall {m :: * -> *}.
StreamK m (StreamK m b) -> StreamK m (StreamK m b)
nonLeafPairs StreamK m (StreamK m b)
r
            in State StreamK m (StreamK m b)
-> (StreamK m b -> StreamK m (StreamK m b) -> m r)
-> (StreamK m b -> m r)
-> m r
-> StreamK m (StreamK m b)
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m b -> State StreamK m (StreamK m b)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m b
st) StreamK m b -> StreamK m (StreamK m b) -> m r
yieldk StreamK m b -> m r
single m r
stop StreamK m (StreamK m b)
stream

    -- Exactly the same as "go" except that stop continuation extracts the
    -- stream.
    leafPairs :: StreamK m a -> StreamK m (StreamK m b)
leafPairs StreamK m a
stream =
        (forall r.
 State StreamK m (StreamK m b)
 -> (StreamK m b -> StreamK m (StreamK m b) -> m r)
 -> (StreamK m b -> m r)
 -> m r
 -> m r)
-> StreamK m (StreamK m b)
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m (StreamK m b)
  -> (StreamK m b -> StreamK m (StreamK m b) -> m r)
  -> (StreamK m b -> m r)
  -> m r
  -> m r)
 -> StreamK m (StreamK m b))
-> (forall r.
    State StreamK m (StreamK m b)
    -> (StreamK m b -> StreamK m (StreamK m b) -> m r)
    -> (StreamK m b -> m r)
    -> m r
    -> m r)
-> StreamK m (StreamK m b)
forall a b. (a -> b) -> a -> b
$ \State StreamK m (StreamK m b)
st StreamK m b -> StreamK m (StreamK m b) -> m r
yld StreamK m b -> m r
sng m r
stp ->
            let foldShared :: StreamK m (StreamK m b) -> m r
foldShared = State StreamK m (StreamK m b)
-> (StreamK m b -> StreamK m (StreamK m b) -> m r)
-> (StreamK m b -> m r)
-> m r
-> StreamK m (StreamK m b)
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m (StreamK m b)
st StreamK m b -> StreamK m (StreamK m b) -> m r
yld StreamK m b -> m r
sng m r
stp
                single :: a -> m r
single a
a   = StreamK m b -> m r
sng (a -> StreamK m b
f a
a)
                yieldk :: a -> StreamK m a -> m r
yieldk a
a StreamK m a
r = StreamK m (StreamK m b) -> m r
foldShared (StreamK m (StreamK m b) -> m r) -> StreamK m (StreamK m b) -> m r
forall a b. (a -> b) -> a -> b
$ a -> StreamK m a -> StreamK m (StreamK m b)
leafPairs1 a
a StreamK m a
r
            in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m (StreamK m b) -> State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m (StreamK m b)
st) a -> StreamK m a -> m r
yieldk a -> m r
single m r
stp StreamK m a
stream

    leafPairs1 :: a -> StreamK m a -> StreamK m (StreamK m b)
leafPairs1 a
a1 StreamK m a
stream =
        (forall r.
 State StreamK m (StreamK m b)
 -> (StreamK m b -> StreamK m (StreamK m b) -> m r)
 -> (StreamK m b -> m r)
 -> m r
 -> m r)
-> StreamK m (StreamK m b)
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m (StreamK m b)
  -> (StreamK m b -> StreamK m (StreamK m b) -> m r)
  -> (StreamK m b -> m r)
  -> m r
  -> m r)
 -> StreamK m (StreamK m b))
-> (forall r.
    State StreamK m (StreamK m b)
    -> (StreamK m b -> StreamK m (StreamK m b) -> m r)
    -> (StreamK m b -> m r)
    -> m r
    -> m r)
-> StreamK m (StreamK m b)
forall a b. (a -> b) -> a -> b
$ \State StreamK m (StreamK m b)
st StreamK m b -> StreamK m (StreamK m b) -> m r
yld StreamK m b -> m r
sng m r
_ ->
            let stop :: m r
stop = StreamK m b -> m r
sng (a -> StreamK m b
f a
a1)
                single :: a -> m r
single a
a = StreamK m b -> m r
sng (a -> StreamK m b
f a
a1 StreamK m b -> StreamK m b -> StreamK m b
`combine` a -> StreamK m b
f a
a)
                yieldk :: a -> StreamK m a -> m r
yieldk a
a StreamK m a
r = StreamK m b -> StreamK m (StreamK m b) -> m r
yld (a -> StreamK m b
f a
a1 StreamK m b -> StreamK m b -> StreamK m b
`combine` a -> StreamK m b
f a
a) (StreamK m (StreamK m b) -> m r) -> StreamK m (StreamK m b) -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m a -> StreamK m (StreamK m b)
leafPairs StreamK m a
r
            in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m (StreamK m b) -> State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m (StreamK m b)
st) a -> StreamK m a -> m r
yieldk a -> m r
single m r
stop StreamK m a
stream

    -- Exactly the same as "leafPairs" except that it does not map "f"
    nonLeafPairs :: StreamK m (StreamK m b) -> StreamK m (StreamK m b)
nonLeafPairs StreamK m (StreamK m b)
stream =
        (forall r.
 State StreamK m (StreamK m b)
 -> (StreamK m b -> StreamK m (StreamK m b) -> m r)
 -> (StreamK m b -> m r)
 -> m r
 -> m r)
-> StreamK m (StreamK m b)
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m (StreamK m b)
  -> (StreamK m b -> StreamK m (StreamK m b) -> m r)
  -> (StreamK m b -> m r)
  -> m r
  -> m r)
 -> StreamK m (StreamK m b))
-> (forall r.
    State StreamK m (StreamK m b)
    -> (StreamK m b -> StreamK m (StreamK m b) -> m r)
    -> (StreamK m b -> m r)
    -> m r
    -> m r)
-> StreamK m (StreamK m b)
forall a b. (a -> b) -> a -> b
$ \State StreamK m (StreamK m b)
st StreamK m b -> StreamK m (StreamK m b) -> m r
yld StreamK m b -> m r
sng m r
stp ->
            let foldShared :: StreamK m (StreamK m b) -> m r
foldShared = State StreamK m (StreamK m b)
-> (StreamK m b -> StreamK m (StreamK m b) -> m r)
-> (StreamK m b -> m r)
-> m r
-> StreamK m (StreamK m b)
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m (StreamK m b)
st StreamK m b -> StreamK m (StreamK m b) -> m r
yld StreamK m b -> m r
sng m r
stp
                single :: StreamK m b -> m r
single StreamK m b
a   = StreamK m b -> m r
sng StreamK m b
a
                yieldk :: StreamK m b -> StreamK m (StreamK m b) -> m r
yieldk StreamK m b
a StreamK m (StreamK m b)
r = StreamK m (StreamK m b) -> m r
foldShared (StreamK m (StreamK m b) -> m r) -> StreamK m (StreamK m b) -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m b -> StreamK m (StreamK m b) -> StreamK m (StreamK m b)
nonLeafPairs1 StreamK m b
a StreamK m (StreamK m b)
r
            in State StreamK m (StreamK m b)
-> (StreamK m b -> StreamK m (StreamK m b) -> m r)
-> (StreamK m b -> m r)
-> m r
-> StreamK m (StreamK m b)
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m (StreamK m b) -> State StreamK m (StreamK m b)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m (StreamK m b)
st) StreamK m b -> StreamK m (StreamK m b) -> m r
yieldk StreamK m b -> m r
single m r
stp StreamK m (StreamK m b)
stream

    nonLeafPairs1 :: StreamK m b -> StreamK m (StreamK m b) -> StreamK m (StreamK m b)
nonLeafPairs1 StreamK m b
a1 StreamK m (StreamK m b)
stream =
        (forall r.
 State StreamK m (StreamK m b)
 -> (StreamK m b -> StreamK m (StreamK m b) -> m r)
 -> (StreamK m b -> m r)
 -> m r
 -> m r)
-> StreamK m (StreamK m b)
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m (StreamK m b)
  -> (StreamK m b -> StreamK m (StreamK m b) -> m r)
  -> (StreamK m b -> m r)
  -> m r
  -> m r)
 -> StreamK m (StreamK m b))
-> (forall r.
    State StreamK m (StreamK m b)
    -> (StreamK m b -> StreamK m (StreamK m b) -> m r)
    -> (StreamK m b -> m r)
    -> m r
    -> m r)
-> StreamK m (StreamK m b)
forall a b. (a -> b) -> a -> b
$ \State StreamK m (StreamK m b)
st StreamK m b -> StreamK m (StreamK m b) -> m r
yld StreamK m b -> m r
sng m r
_ ->
            let stop :: m r
stop = StreamK m b -> m r
sng StreamK m b
a1
                single :: StreamK m b -> m r
single StreamK m b
a = StreamK m b -> m r
sng (StreamK m b
a1 StreamK m b -> StreamK m b -> StreamK m b
`combine` StreamK m b
a)
                yieldk :: StreamK m b -> StreamK m (StreamK m b) -> m r
yieldk StreamK m b
a StreamK m (StreamK m b)
r = StreamK m b -> StreamK m (StreamK m b) -> m r
yld (StreamK m b
a1 StreamK m b -> StreamK m b -> StreamK m b
`combine` StreamK m b
a) (StreamK m (StreamK m b) -> m r) -> StreamK m (StreamK m b) -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m (StreamK m b) -> StreamK m (StreamK m b)
nonLeafPairs StreamK m (StreamK m b)
r
            in State StreamK m (StreamK m b)
-> (StreamK m b -> StreamK m (StreamK m b) -> m r)
-> (StreamK m b -> m r)
-> m r
-> StreamK m (StreamK m b)
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m (StreamK m b) -> State StreamK m (StreamK m b)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m (StreamK m b)
st) StreamK m b -> StreamK m (StreamK m b) -> m r
yieldk StreamK m b -> m r
single m r
stop StreamK m (StreamK m b)
stream

{-
instance Monad m => Applicative (StreamK m) where
    {-# INLINE pure #-}
    pure = fromPure

    {-# INLINE (<*>) #-}
    (<*>) = crossApply

    {-# INLINE liftA2 #-}
    liftA2 f x = (<*>) (fmap f x)

    {-# INLINE (*>) #-}
    (*>) = crossApplySnd

    {-# INLINE (<*) #-}
    (<*) = crossApplyFst

-- NOTE: even though concatMap for StreamD is 3x faster compared to StreamK,
-- the monad instance of StreamD is slower than StreamK after foldr/build
-- fusion.
instance Monad m => Monad (StreamK m) where
    {-# INLINE return #-}
    return = pure

    {-# INLINE (>>=) #-}
    (>>=) = flip concatMap
-}

{-
-- Like concatMap but generates stream using an unfold function. Similar to
-- unfoldMany but for StreamK.
concatUnfoldr :: IsStream t
    => (b -> t m (Maybe (a, b))) -> t m b -> t m a
concatUnfoldr = undefined
-}

------------------------------------------------------------------------------
-- concatIterate - Map and flatten Trees of Streams
------------------------------------------------------------------------------

-- | Yield an input element in the output stream, map a stream generator on it
-- and repeat the process on the resulting stream. Resulting streams are
-- flattened using the 'concatMapWith' combinator. This can be used for a depth
-- first style (DFS) traversal of a tree like structure.
--
-- Example, list a directory tree using DFS:
--
-- >>> f = StreamK.fromStream . either Dir.readEitherPaths (const Stream.nil)
-- >>> input = StreamK.fromPure (Left ".")
-- >>> ls = StreamK.concatIterateWith StreamK.append f input
--
-- Note that 'iterateM' is a special case of 'concatIterateWith':
--
-- >>> iterateM f = StreamK.concatIterateWith StreamK.append (StreamK.fromEffect . f) . StreamK.fromEffect
--
-- /Pre-release/
--
{-# INLINE concatIterateWith #-}
concatIterateWith ::
       (StreamK m a -> StreamK m a -> StreamK m a)
    -> (a -> StreamK m a)
    -> StreamK m a
    -> StreamK m a
concatIterateWith :: forall (m :: * -> *) a.
(StreamK m a -> StreamK m a -> StreamK m a)
-> (a -> StreamK m a) -> StreamK m a -> StreamK m a
concatIterateWith StreamK m a -> StreamK m a -> StreamK m a
combine a -> StreamK m a
f = StreamK m a -> StreamK m a
iterateStream

    where

    iterateStream :: StreamK m a -> StreamK m a
iterateStream = (StreamK m a -> StreamK m a -> StreamK m a)
-> (a -> StreamK m a) -> StreamK m a -> StreamK m a
forall (m :: * -> *) b a.
(StreamK m b -> StreamK m b -> StreamK m b)
-> (a -> StreamK m b) -> StreamK m a -> StreamK m b
concatMapWith StreamK m a -> StreamK m a -> StreamK m a
combine a -> StreamK m a
generate

    generate :: a -> StreamK m a
generate a
x = a
x a -> StreamK m a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
`cons` StreamK m a -> StreamK m a
iterateStream (a -> StreamK m a
f a
x)

-- | Like 'concatIterateWith' but uses the pairwise flattening combinator
-- 'mergeMapWith' for flattening the resulting streams. This can be used for a
-- balanced traversal of a tree like structure.
--
-- Example, list a directory tree using balanced traversal:
--
-- >>> f = StreamK.fromStream . either Dir.readEitherPaths (const Stream.nil)
-- >>> input = StreamK.fromPure (Left ".")
-- >>> ls = StreamK.mergeIterateWith StreamK.interleave f input
--
-- /Pre-release/
--
{-# INLINE mergeIterateWith #-}
mergeIterateWith ::
       (StreamK m a -> StreamK m a -> StreamK m a)
    -> (a -> StreamK m a)
    -> StreamK m a
    -> StreamK m a
mergeIterateWith :: forall (m :: * -> *) a.
(StreamK m a -> StreamK m a -> StreamK m a)
-> (a -> StreamK m a) -> StreamK m a -> StreamK m a
mergeIterateWith StreamK m a -> StreamK m a -> StreamK m a
combine a -> StreamK m a
f = StreamK m a -> StreamK m a
iterateStream

    where

    iterateStream :: StreamK m a -> StreamK m a
iterateStream = (StreamK m a -> StreamK m a -> StreamK m a)
-> (a -> StreamK m a) -> StreamK m a -> StreamK m a
forall (m :: * -> *) b a.
(StreamK m b -> StreamK m b -> StreamK m b)
-> (a -> StreamK m b) -> StreamK m a -> StreamK m b
mergeMapWith StreamK m a -> StreamK m a -> StreamK m a
combine a -> StreamK m a
generate

    generate :: a -> StreamK m a
generate a
x = a
x a -> StreamK m a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
`cons` StreamK m a -> StreamK m a
iterateStream (a -> StreamK m a
f a
x)

------------------------------------------------------------------------------
-- Flattening Graphs
------------------------------------------------------------------------------

-- To traverse graphs we need a state to be carried around in the traversal.
-- For example, we can use a hashmap to store the visited status of nodes.

-- | Like 'iterateMap' but carries a state in the stream generation function.
-- This can be used to traverse graph like structures, we can remember the
-- visited nodes in the state to avoid cycles.
--
-- Note that a combination of 'iterateMap' and 'usingState' can also be used to
-- traverse graphs. However, this function provides a more localized state
-- instead of using a global state.
--
-- See also: 'mfix'
--
-- /Pre-release/
--
{-# INLINE concatIterateScanWith #-}
concatIterateScanWith
    :: Monad m
    => (StreamK m a -> StreamK m a -> StreamK m a)
    -> (b -> a -> m (b, StreamK m a))
    -> m b
    -> StreamK m a
    -> StreamK m a
concatIterateScanWith :: forall (m :: * -> *) a b.
Monad m =>
(StreamK m a -> StreamK m a -> StreamK m a)
-> (b -> a -> m (b, StreamK m a))
-> m b
-> StreamK m a
-> StreamK m a
concatIterateScanWith StreamK m a -> StreamK m a -> StreamK m a
combine b -> a -> m (b, StreamK m a)
f m b
initial StreamK m a
stream =
    m (StreamK m a) -> StreamK m a
forall (m :: * -> *) a. Monad m => m (StreamK m a) -> StreamK m a
concatEffect (m (StreamK m a) -> StreamK m a) -> m (StreamK m a) -> StreamK m a
forall a b. (a -> b) -> a -> b
$ do
        b
b <- m b
initial
        (b, StreamK m a) -> m (StreamK m a)
iterateStream (b
b, StreamK m a
stream)

    where

    iterateStream :: (b, StreamK m a) -> m (StreamK m a)
iterateStream (b
b, StreamK m a
s) = StreamK m a -> m (StreamK m a)
forall a. a -> m a
forall (f :: * -> *) a. Applicative f => a -> f a
pure (StreamK m a -> m (StreamK m a)) -> StreamK m a -> m (StreamK m a)
forall a b. (a -> b) -> a -> b
$ (StreamK m a -> StreamK m a -> StreamK m a)
-> (a -> StreamK m a) -> StreamK m a -> StreamK m a
forall (m :: * -> *) b a.
(StreamK m b -> StreamK m b -> StreamK m b)
-> (a -> StreamK m b) -> StreamK m a -> StreamK m b
concatMapWith StreamK m a -> StreamK m a -> StreamK m a
combine (b -> a -> StreamK m a
generate b
b) StreamK m a
s

    generate :: b -> a -> StreamK m a
generate b
b a
a = a
a a -> StreamK m a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
`cons` b -> a -> StreamK m a
feedback b
b a
a

    feedback :: b -> a -> StreamK m a
feedback b
b a
a = m (StreamK m a) -> StreamK m a
forall (m :: * -> *) a. Monad m => m (StreamK m a) -> StreamK m a
concatEffect (m (StreamK m a) -> StreamK m a) -> m (StreamK m a) -> StreamK m a
forall a b. (a -> b) -> a -> b
$ b -> a -> m (b, StreamK m a)
f b
b a
a m (b, StreamK m a)
-> ((b, StreamK m a) -> m (StreamK m a)) -> m (StreamK m a)
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= (b, StreamK m a) -> m (StreamK m a)
iterateStream

------------------------------------------------------------------------------
-- Either streams
------------------------------------------------------------------------------

-- Keep concating either streams as long as rights are generated, stop as soon
-- as a left is generated and concat the left stream.
--
-- See also: 'handle'
--
-- /Unimplemented/
--
{-
concatMapEitherWith
    :: (forall x. t m x -> t m x -> t m x)
    -> (a -> t m (Either (StreamK m b) b))
    -> StreamK m a
    -> StreamK m b
concatMapEitherWith = undefined
-}

-- XXX We should prefer using the Maybe stream returning signatures over this.
-- This API should perhaps be removed in favor of those.

-- | In an 'Either' stream iterate on 'Left's.  This is a special case of
-- 'concatIterateWith':
--
-- >>> concatIterateLeftsWith combine f = StreamK.concatIterateWith combine (either f (const StreamK.nil))
--
-- To traverse a directory tree:
--
-- >>> input = StreamK.fromPure (Left ".")
-- >>> ls = StreamK.concatIterateLeftsWith StreamK.append (StreamK.fromStream . Dir.readEither) input
--
-- /Pre-release/
--
{-# INLINE concatIterateLeftsWith #-}
concatIterateLeftsWith
    :: (b ~ Either a c)
    => (StreamK m b -> StreamK m b -> StreamK m b)
    -> (a -> StreamK m b)
    -> StreamK m b
    -> StreamK m b
concatIterateLeftsWith :: forall b a c (m :: * -> *).
(b ~ Either a c) =>
(StreamK m b -> StreamK m b -> StreamK m b)
-> (a -> StreamK m b) -> StreamK m b -> StreamK m b
concatIterateLeftsWith StreamK m b -> StreamK m b -> StreamK m b
combine a -> StreamK m b
f =
    (StreamK m b -> StreamK m b -> StreamK m b)
-> (b -> StreamK m b) -> StreamK m b -> StreamK m b
forall (m :: * -> *) a.
(StreamK m a -> StreamK m a -> StreamK m a)
-> (a -> StreamK m a) -> StreamK m a -> StreamK m a
concatIterateWith StreamK m b -> StreamK m b -> StreamK m b
combine ((a -> StreamK m b)
-> (c -> StreamK m b) -> Either a c -> StreamK m b
forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either a -> StreamK m b
f (StreamK m b -> c -> StreamK m b
forall a b. a -> b -> a
const StreamK m b
forall (m :: * -> *) a. StreamK m a
nil))

------------------------------------------------------------------------------
-- Interleaving
------------------------------------------------------------------------------

infixr 6 `interleave`

-- Additionally we can have m elements yield from the first stream and n
-- elements yielding from the second stream. We can also have time slicing
-- variants of positional interleaving, e.g. run first stream for m seconds and
-- run the second stream for n seconds.

-- | Note: When joining many streams in a left associative manner earlier
-- streams will get exponential priority than the ones joining later. Because
-- of exponentially high weighting of left streams it can be used with
-- 'concatMapWith' even on a large number of streams.
--
{-# INLINE interleave #-}
interleave :: StreamK m a -> StreamK m a -> StreamK m a
interleave :: forall (m :: * -> *) a. StreamK m a -> StreamK m a -> StreamK m a
interleave StreamK m a
m1 StreamK m a
m2 = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp -> do
    let stop :: m r
stop       = State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp StreamK m a
m2
        single :: a -> m r
single a
a   = a -> StreamK m a -> m r
yld a
a StreamK m a
m2
        yieldk :: a -> StreamK m a -> m r
yieldk a
a StreamK m a
r = a -> StreamK m a -> m r
yld a
a (StreamK m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) a. StreamK m a -> StreamK m a -> StreamK m a
interleave StreamK m a
m2 StreamK m a
r)
    State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yieldk a -> m r
single m r
stop StreamK m a
m1

infixr 6 `interleaveFst`

-- | Like `interleave` but stops interleaving as soon as the first stream stops.
--
{-# INLINE interleaveFst #-}
interleaveFst :: StreamK m a -> StreamK m a -> StreamK m a
interleaveFst :: forall (m :: * -> *) a. StreamK m a -> StreamK m a -> StreamK m a
interleaveFst StreamK m a
m1 StreamK m a
m2 = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp -> do
    let yieldFirst :: a -> StreamK m a -> m r
yieldFirst a
a StreamK m a
r = a -> StreamK m a -> m r
yld a
a (StreamK m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) a. StreamK m a -> StreamK m a -> StreamK m a
yieldSecond StreamK m a
r StreamK m a
m2)
     in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yieldFirst a -> m r
sng m r
stp StreamK m a
m1

    where

    yieldSecond :: StreamK m a -> StreamK m a -> StreamK m a
yieldSecond StreamK m a
s1 StreamK m a
s2 = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp -> do
            let stop :: m r
stop       = State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp StreamK m a
s1
                single :: a -> m r
single a
a   = a -> StreamK m a -> m r
yld a
a StreamK m a
s1
                yieldk :: a -> StreamK m a -> m r
yieldk a
a StreamK m a
r = a -> StreamK m a -> m r
yld a
a (StreamK m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) a. StreamK m a -> StreamK m a -> StreamK m a
interleave StreamK m a
s1 StreamK m a
r)
             in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yieldk a -> m r
single m r
stop StreamK m a
s2

infixr 6 `interleaveMin`

-- | Like `interleave` but stops interleaving as soon as any of the two streams
-- stops.
--
{-# INLINE interleaveMin #-}
interleaveMin :: StreamK m a -> StreamK m a -> StreamK m a
interleaveMin :: forall (m :: * -> *) a. StreamK m a -> StreamK m a -> StreamK m a
interleaveMin StreamK m a
m1 StreamK m a
m2 = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
_ m r
stp -> do
    let stop :: m r
stop       = m r
stp
        -- "single a" is defined as "yld a (interleaveMin m2 nil)" instead of
        -- "sng a" to keep the behaviour consistent with the yield
        -- continuation.
        single :: a -> m r
single a
a   = a -> StreamK m a -> m r
yld a
a (StreamK m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) a. StreamK m a -> StreamK m a -> StreamK m a
interleaveMin StreamK m a
m2 StreamK m a
forall (m :: * -> *) a. StreamK m a
nil)
        yieldk :: a -> StreamK m a -> m r
yieldk a
a StreamK m a
r = a -> StreamK m a -> m r
yld a
a (StreamK m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) a. StreamK m a -> StreamK m a -> StreamK m a
interleaveMin StreamK m a
m2 StreamK m a
r)
    State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yieldk a -> m r
single m r
stop StreamK m a
m1

-------------------------------------------------------------------------------
-- Generation
-------------------------------------------------------------------------------

-- |
-- >>> :{
-- unfoldr step s =
--     case step s of
--         Nothing -> StreamK.nil
--         Just (a, b) -> a `StreamK.cons` unfoldr step b
-- :}
--
-- Build a stream by unfolding a /pure/ step function @step@ starting from a
-- seed @s@.  The step function returns the next element in the stream and the
-- next seed value. When it is done it returns 'Nothing' and the stream ends.
-- For example,
--
-- >>> :{
-- let f b =
--         if b > 2
--         then Nothing
--         else Just (b, b + 1)
-- in StreamK.toList $ StreamK.unfoldr f 0
-- :}
-- [0,1,2]
--
{-# INLINE unfoldr #-}
unfoldr :: (b -> Maybe (a, b)) -> b -> StreamK m a
unfoldr :: forall b a (m :: * -> *). (b -> Maybe (a, b)) -> b -> StreamK m a
unfoldr b -> Maybe (a, b)
next b
s0 = (forall b. (a -> b -> b) -> b -> b) -> StreamK m a
forall (m :: * -> *) a.
(forall b. (a -> b -> b) -> b -> b) -> StreamK m a
build ((forall b. (a -> b -> b) -> b -> b) -> StreamK m a)
-> (forall b. (a -> b -> b) -> b -> b) -> StreamK m a
forall a b. (a -> b) -> a -> b
$ \a -> b -> b
yld b
stp ->
    let go :: b -> b
go b
s =
            case b -> Maybe (a, b)
next b
s of
                Just (a
a, b
b) -> a -> b -> b
yld a
a (b -> b
go b
b)
                Maybe (a, b)
Nothing -> b
stp
    in b -> b
go b
s0

{-# INLINE unfoldrMWith #-}
unfoldrMWith :: Monad m =>
       (m a -> StreamK m a -> StreamK m a)
    -> (b -> m (Maybe (a, b)))
    -> b
    -> StreamK m a
unfoldrMWith :: forall (m :: * -> *) a b.
Monad m =>
(m a -> StreamK m a -> StreamK m a)
-> (b -> m (Maybe (a, b))) -> b -> StreamK m a
unfoldrMWith m a -> StreamK m a -> StreamK m a
cns b -> m (Maybe (a, b))
step = b -> StreamK m a
go

    where

    go :: b -> StreamK m a
go b
s = (m a -> StreamK m a -> StreamK m a)
-> (forall r.
    (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
Monad m =>
(m a -> StreamK m a -> StreamK m a)
-> (forall r.
    (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
sharedMWith m a -> StreamK m a -> StreamK m a
cns ((forall r. (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \a -> StreamK m a -> m r
yld a -> m r
_ m r
stp -> do
                Maybe (a, b)
r <- b -> m (Maybe (a, b))
step b
s
                case Maybe (a, b)
r of
                    Just (a
a, b
b) -> a -> StreamK m a -> m r
yld a
a (b -> StreamK m a
go b
b)
                    Maybe (a, b)
Nothing -> m r
stp

-- | Build a stream by unfolding a /monadic/ step function starting from a
-- seed.  The step function returns the next element in the stream and the next
-- seed value. When it is done it returns 'Nothing' and the stream ends. For
-- example,
--
-- >>> :{
-- let f b =
--         if b > 2
--         then return Nothing
--         else return (Just (b, b + 1))
-- in StreamK.toList $ StreamK.unfoldrM f 0
-- :}
-- [0,1,2]
--
{-# INLINE unfoldrM #-}
unfoldrM :: Monad m => (b -> m (Maybe (a, b))) -> b -> StreamK m a
unfoldrM :: forall (m :: * -> *) b a.
Monad m =>
(b -> m (Maybe (a, b))) -> b -> StreamK m a
unfoldrM = (m a -> StreamK m a -> StreamK m a)
-> (b -> m (Maybe (a, b))) -> b -> StreamK m a
forall (m :: * -> *) a b.
Monad m =>
(m a -> StreamK m a -> StreamK m a)
-> (b -> m (Maybe (a, b))) -> b -> StreamK m a
unfoldrMWith m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) a.
Monad m =>
m a -> StreamK m a -> StreamK m a
consM

-- | Generate an infinite stream by repeating a pure value.
--
-- /Pre-release/
{-# INLINE repeat #-}
repeat :: a -> StreamK m a
repeat :: forall a (m :: * -> *). a -> StreamK m a
repeat a
a = let x :: StreamK m a
x = a -> StreamK m a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
cons a
a StreamK m a
x in StreamK m a
forall {m :: * -> *}. StreamK m a
x

-- | Like 'repeatM' but takes a stream 'cons' operation to combine the actions
-- in a stream specific manner. A serial cons would repeat the values serially
-- while an async cons would repeat concurrently.
--
-- /Pre-release/
repeatMWith :: (m a -> t m a -> t m a) -> m a -> t m a
repeatMWith :: forall (m :: * -> *) a (t :: (* -> *) -> * -> *).
(m a -> t m a -> t m a) -> m a -> t m a
repeatMWith m a -> t m a -> t m a
cns = m a -> t m a
go

    where

    go :: m a -> t m a
go m a
m = m a
m m a -> t m a -> t m a
`cns` m a -> t m a
go m a
m

{-# INLINE replicateMWith #-}
replicateMWith :: (m a -> StreamK m a -> StreamK m a) -> Int -> m a -> StreamK m a
replicateMWith :: forall (m :: * -> *) a.
(m a -> StreamK m a -> StreamK m a) -> Int -> m a -> StreamK m a
replicateMWith m a -> StreamK m a -> StreamK m a
cns Int
n m a
m = Int -> StreamK m a
forall {t}. (Ord t, Num t) => t -> StreamK m a
go Int
n

    where

    go :: t -> StreamK m a
go t
cnt = if t
cnt t -> t -> Bool
forall a. Ord a => a -> a -> Bool
<= t
0 then StreamK m a
forall (m :: * -> *) a. StreamK m a
nil else m a
m m a -> StreamK m a -> StreamK m a
`cns` t -> StreamK m a
go (t
cnt t -> t -> t
forall a. Num a => a -> a -> a
- t
1)

{-# INLINE fromIndicesMWith #-}
fromIndicesMWith ::
    (m a -> StreamK m a -> StreamK m a) -> (Int -> m a) -> StreamK m a
fromIndicesMWith :: forall (m :: * -> *) a.
(m a -> StreamK m a -> StreamK m a) -> (Int -> m a) -> StreamK m a
fromIndicesMWith m a -> StreamK m a -> StreamK m a
cns Int -> m a
gen = Int -> StreamK m a
go Int
0

    where

    go :: Int -> StreamK m a
go Int
i = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
stp a -> m r
sng m r
yld -> do
        State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m a
st a -> StreamK m a -> m r
stp a -> m r
sng m r
yld (Int -> m a
gen Int
i m a -> StreamK m a -> StreamK m a
`cns` Int -> StreamK m a
go (Int
i Int -> Int -> Int
forall a. Num a => a -> a -> a
+ Int
1))

{-# INLINE iterateMWith #-}
iterateMWith :: Monad m =>
    (m a -> StreamK m a -> StreamK m a) -> (a -> m a) -> m a -> StreamK m a
iterateMWith :: forall (m :: * -> *) a.
Monad m =>
(m a -> StreamK m a -> StreamK m a)
-> (a -> m a) -> m a -> StreamK m a
iterateMWith m a -> StreamK m a -> StreamK m a
cns a -> m a
step = m a -> StreamK m a
go

    where

    go :: m a -> StreamK m a
go m a
s = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
stp a -> m r
sng m r
yld -> do
        !a
next <- m a
s
        State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m a
st a -> StreamK m a -> m r
stp a -> m r
sng m r
yld (a -> m a
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return a
next m a -> StreamK m a -> StreamK m a
`cns` m a -> StreamK m a
go (a -> m a
step a
next))

{-# INLINE headPartial #-}
headPartial :: Monad m => StreamK m a -> m a
headPartial :: forall (m :: * -> *) a. Monad m => StreamK m a -> m a
headPartial = (a -> m a -> m a) -> m a -> StreamK m a -> m a
forall a (m :: * -> *) b.
(a -> m b -> m b) -> m b -> StreamK m a -> m b
foldrM (\a
x m a
_ -> a -> m a
forall a. a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return a
x) (String -> m a
forall a. HasCallStack => String -> a
error String
"head of nil")

{-# INLINE tailPartial #-}
tailPartial :: StreamK m a -> StreamK m a
tailPartial :: forall (m :: * -> *) a. StreamK m a -> StreamK m a
tailPartial StreamK m a
m = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
    let stop :: a
stop      = String -> a
forall a. HasCallStack => String -> a
error String
"tail of nil"
        single :: p -> m r
single p
_  = m r
stp
        yieldk :: p -> StreamK m a -> m r
yieldk p
_ StreamK m a
r = State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp StreamK m a
r
    in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
forall {p}. p -> StreamK m a -> m r
yieldk a -> m r
forall {p}. p -> m r
single m r
forall {a}. a
stop StreamK m a
m

-- | We can define cyclic structures using @let@:
--
-- >>> let (a, b) = ([1, b], head a) in (a, b)
-- ([1,1],1)
--
-- The function @fix@ defined as:
--
-- >>> fix f = let x = f x in x
--
-- ensures that the argument of a function and its output refer to the same
-- lazy value @x@ i.e.  the same location in memory.  Thus @x@ can be defined
-- in terms of itself, creating structures with cyclic references.
--
-- >>> f ~(a, b) = ([1, b], head a)
-- >>> fix f
-- ([1,1],1)
--
-- 'Control.Monad.mfix' is essentially the same as @fix@ but for monadic
-- values.
--
-- Using 'mfix' for streams we can construct a stream in which each element of
-- the stream is defined in a cyclic fashion. The argument of the function
-- being fixed represents the current element of the stream which is being
-- returned by the stream monad. Thus, we can use the argument to construct
-- itself.
--
-- In the following example, the argument @action@ of the function @f@
-- represents the tuple @(x,y)@ returned by it in a given iteration. We define
-- the first element of the tuple in terms of the second.
--
-- >>> import System.IO.Unsafe (unsafeInterleaveIO)
--
-- >>> :{
-- main = Stream.fold (Fold.drainMapM print) $ StreamK.toStream $ StreamK.mfix f
--     where
--     f action = StreamK.unCross $ do
--         let incr n act = fmap ((+n) . snd) $ unsafeInterleaveIO act
--         x <- StreamK.mkCross $ StreamK.fromStream $ Stream.sequence $ Stream.fromList [incr 1 action, incr 2 action]
--         y <- StreamK.mkCross $ StreamK.fromStream $ Stream.fromList [4,5]
--         return (x, y)
-- :}
--
-- Note: you cannot achieve this by just changing the order of the monad
-- statements because that would change the order in which the stream elements
-- are generated.
--
-- Note that the function @f@ must be lazy in its argument, that's why we use
-- 'unsafeInterleaveIO' on @action@ because IO monad is strict.
--
-- /Pre-release/
{-# INLINE mfix #-}
mfix :: Monad m => (m a -> StreamK m a) -> StreamK m a
mfix :: forall (m :: * -> *) a.
Monad m =>
(m a -> StreamK m a) -> StreamK m a
mfix m a -> StreamK m a
f = (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
    let single :: a -> m r
single a
a  = State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp (StreamK m a -> m r) -> StreamK m a -> m r
forall a b. (a -> b) -> a -> b
$ a
a a -> StreamK m a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
`cons` StreamK m a
ys
        yieldk :: a -> p -> m r
yieldk a
a p
_ = State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp (StreamK m a -> m r) -> StreamK m a -> m r
forall a b. (a -> b) -> a -> b
$ a
a a -> StreamK m a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
`cons` StreamK m a
ys
    in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
st a -> StreamK m a -> m r
forall {p}. a -> p -> m r
yieldk a -> m r
single m r
stp StreamK m a
xs

    where

    -- fix the head element of the stream
    xs :: StreamK m a
xs = (StreamK m a -> StreamK m a) -> StreamK m a
forall a. (a -> a) -> a
fix  (m a -> StreamK m a
f (m a -> StreamK m a)
-> (StreamK m a -> m a) -> StreamK m a -> StreamK m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. StreamK m a -> m a
forall (m :: * -> *) a. Monad m => StreamK m a -> m a
headPartial)

    -- now fix the tail recursively
    ys :: StreamK m a
ys = (m a -> StreamK m a) -> StreamK m a
forall (m :: * -> *) a.
Monad m =>
(m a -> StreamK m a) -> StreamK m a
mfix (StreamK m a -> StreamK m a
forall (m :: * -> *) a. StreamK m a -> StreamK m a
tailPartial (StreamK m a -> StreamK m a)
-> (m a -> StreamK m a) -> m a -> StreamK m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. m a -> StreamK m a
f)

-------------------------------------------------------------------------------
-- Conversions
-------------------------------------------------------------------------------

-- |
-- >>> fromFoldable = Prelude.foldr StreamK.cons StreamK.nil
--
-- Construct a stream from a 'Foldable' containing pure values:
--
{-# INLINE fromFoldable #-}
fromFoldable :: Foldable f => f a -> StreamK m a
fromFoldable :: forall (f :: * -> *) a (m :: * -> *).
Foldable f =>
f a -> StreamK m a
fromFoldable = (a -> StreamK m a -> StreamK m a)
-> StreamK m a -> f a -> StreamK m a
forall a b. (a -> b -> b) -> b -> f a -> b
forall (t :: * -> *) a b.
Foldable t =>
(a -> b -> b) -> b -> t a -> b
Prelude.foldr a -> StreamK m a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
cons StreamK m a
forall (m :: * -> *) a. StreamK m a
nil

{-# INLINE fromFoldableM #-}
fromFoldableM :: (Foldable f, Monad m) => f (m a) -> StreamK m a
fromFoldableM :: forall (f :: * -> *) (m :: * -> *) a.
(Foldable f, Monad m) =>
f (m a) -> StreamK m a
fromFoldableM = (m a -> StreamK m a -> StreamK m a)
-> StreamK m a -> f (m a) -> StreamK m a
forall a b. (a -> b -> b) -> b -> f a -> b
forall (t :: * -> *) a b.
Foldable t =>
(a -> b -> b) -> b -> t a -> b
Prelude.foldr m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) a.
Monad m =>
m a -> StreamK m a -> StreamK m a
consM StreamK m a
forall (m :: * -> *) a. StreamK m a
nil

-------------------------------------------------------------------------------
-- Deconstruction
-------------------------------------------------------------------------------

{-# INLINE uncons #-}
uncons :: Applicative m => StreamK m a -> m (Maybe (a, StreamK m a))
uncons :: forall (m :: * -> *) a.
Applicative m =>
StreamK m a -> m (Maybe (a, StreamK m a))
uncons StreamK m a
m =
    let stop :: m (Maybe a)
stop = Maybe a -> m (Maybe a)
forall a. a -> m a
forall (f :: * -> *) a. Applicative f => a -> f a
pure Maybe a
forall a. Maybe a
Nothing
        single :: a -> f (Maybe (a, StreamK m a))
single a
a = Maybe (a, StreamK m a) -> f (Maybe (a, StreamK m a))
forall a. a -> f a
forall (f :: * -> *) a. Applicative f => a -> f a
pure ((a, StreamK m a) -> Maybe (a, StreamK m a)
forall a. a -> Maybe a
Just (a
a, StreamK m a
forall (m :: * -> *) a. StreamK m a
nil))
        yieldk :: a -> b -> f (Maybe (a, b))
yieldk a
a b
r = Maybe (a, b) -> f (Maybe (a, b))
forall a. a -> f a
forall (f :: * -> *) a. Applicative f => a -> f a
pure ((a, b) -> Maybe (a, b)
forall a. a -> Maybe a
Just (a
a, b
r))
    in State StreamK m a
-> (a -> StreamK m a -> m (Maybe (a, StreamK m a)))
-> (a -> m (Maybe (a, StreamK m a)))
-> m (Maybe (a, StreamK m a))
-> StreamK m a
-> m (Maybe (a, StreamK m a))
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a. State t m a
defState a -> StreamK m a -> m (Maybe (a, StreamK m a))
forall {f :: * -> *} {a} {b}.
Applicative f =>
a -> b -> f (Maybe (a, b))
yieldk a -> m (Maybe (a, StreamK m a))
forall {f :: * -> *} {a} {m :: * -> *} {a}.
Applicative f =>
a -> f (Maybe (a, StreamK m a))
single m (Maybe (a, StreamK m a))
forall {a}. m (Maybe a)
stop StreamK m a
m

{-# INLINE tail #-}
tail :: Applicative m => StreamK m a -> m (Maybe (StreamK m a))
tail :: forall (m :: * -> *) a.
Applicative m =>
StreamK m a -> m (Maybe (StreamK m a))
tail =
    let stop :: m (Maybe a)
stop      = Maybe a -> m (Maybe a)
forall a. a -> m a
forall (f :: * -> *) a. Applicative f => a -> f a
pure Maybe a
forall a. Maybe a
Nothing
        single :: p -> f (Maybe (StreamK m a))
single p
_  = Maybe (StreamK m a) -> f (Maybe (StreamK m a))
forall a. a -> f a
forall (f :: * -> *) a. Applicative f => a -> f a
pure (Maybe (StreamK m a) -> f (Maybe (StreamK m a)))
-> Maybe (StreamK m a) -> f (Maybe (StreamK m a))
forall a b. (a -> b) -> a -> b
$ StreamK m a -> Maybe (StreamK m a)
forall a. a -> Maybe a
Just StreamK m a
forall (m :: * -> *) a. StreamK m a
nil
        yieldk :: p -> a -> f (Maybe a)
yieldk p
_ a
r = Maybe a -> f (Maybe a)
forall a. a -> f a
forall (f :: * -> *) a. Applicative f => a -> f a
pure (Maybe a -> f (Maybe a)) -> Maybe a -> f (Maybe a)
forall a b. (a -> b) -> a -> b
$ a -> Maybe a
forall a. a -> Maybe a
Just a
r
    in State StreamK m a
-> (a -> StreamK m a -> m (Maybe (StreamK m a)))
-> (a -> m (Maybe (StreamK m a)))
-> m (Maybe (StreamK m a))
-> StreamK m a
-> m (Maybe (StreamK m a))
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a. State t m a
defState a -> StreamK m a -> m (Maybe (StreamK m a))
forall {f :: * -> *} {p} {a}.
Applicative f =>
p -> a -> f (Maybe a)
yieldk a -> m (Maybe (StreamK m a))
forall {f :: * -> *} {p} {m :: * -> *} {a}.
Applicative f =>
p -> f (Maybe (StreamK m a))
single m (Maybe (StreamK m a))
forall {a}. m (Maybe a)
stop

-- | Extract all but the last element of the stream, if any.
--
-- Note: This will end up buffering the entire stream.
--
-- /Pre-release/
{-# INLINE init #-}
init :: Applicative m => StreamK m a -> m (Maybe (StreamK m a))
init :: forall (m :: * -> *) a.
Applicative m =>
StreamK m a -> m (Maybe (StreamK m a))
init = StreamK m a -> m (Maybe (StreamK m a))
forall (m :: * -> *) a.
Applicative m =>
StreamK m a -> m (Maybe (StreamK m a))
go1
    where
    go1 :: StreamK m t -> m (Maybe (StreamK m t))
go1 StreamK m t
m1 = do
        (\case
            Maybe (t, StreamK m t)
Nothing -> Maybe (StreamK m t)
forall a. Maybe a
Nothing
            Just (t
h, StreamK m t
t) -> StreamK m t -> Maybe (StreamK m t)
forall a. a -> Maybe a
Just (StreamK m t -> Maybe (StreamK m t))
-> StreamK m t -> Maybe (StreamK m t)
forall a b. (a -> b) -> a -> b
$ t -> StreamK m t -> StreamK m t
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
go t
h StreamK m t
t) (Maybe (t, StreamK m t) -> Maybe (StreamK m t))
-> m (Maybe (t, StreamK m t)) -> m (Maybe (StreamK m t))
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> StreamK m t -> m (Maybe (t, StreamK m t))
forall (m :: * -> *) a.
Applicative m =>
StreamK m a -> m (Maybe (a, StreamK m a))
uncons StreamK m t
m1
    go :: t -> StreamK m t -> StreamK m t
go t
p StreamK m t
m1 = (forall r.
 State StreamK m t
 -> (t -> StreamK m t -> m r) -> (t -> m r) -> m r -> m r)
-> StreamK m t
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m t
  -> (t -> StreamK m t -> m r) -> (t -> m r) -> m r -> m r)
 -> StreamK m t)
-> (forall r.
    State StreamK m t
    -> (t -> StreamK m t -> m r) -> (t -> m r) -> m r -> m r)
-> StreamK m t
forall a b. (a -> b) -> a -> b
$ \State StreamK m t
_ t -> StreamK m t -> m r
yld t -> m r
sng m r
stp ->
        let single :: p -> m r
single p
_ = t -> m r
sng t
p
            yieldk :: t -> StreamK m t -> m r
yieldk t
a StreamK m t
x = t -> StreamK m t -> m r
yld t
p (StreamK m t -> m r) -> StreamK m t -> m r
forall a b. (a -> b) -> a -> b
$ t -> StreamK m t -> StreamK m t
go t
a StreamK m t
x
         in State StreamK m t
-> (t -> StreamK m t -> m r)
-> (t -> m r)
-> m r
-> StreamK m t
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m t
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a. State t m a
defState t -> StreamK m t -> m r
yieldk t -> m r
forall {p}. p -> m r
single m r
stp StreamK m t
m1

------------------------------------------------------------------------------
-- Reordering
------------------------------------------------------------------------------

-- | Lazy left fold to a stream.
{-# INLINE foldlS #-}
foldlS ::
    (StreamK m b -> a -> StreamK m b) -> StreamK m b -> StreamK m a -> StreamK m b
foldlS :: forall (m :: * -> *) b a.
(StreamK m b -> a -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
foldlS StreamK m b -> a -> StreamK m b
step = StreamK m b -> StreamK m a -> StreamK m b
go
    where
    go :: StreamK m b -> StreamK m a -> StreamK m b
go StreamK m b
acc StreamK m a
rest = (forall r.
 State StreamK m b
 -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m b
  -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
 -> StreamK m b)
-> (forall r.
    State StreamK m b
    -> (b -> StreamK m b -> m r) -> (b -> m r) -> m r -> m r)
-> StreamK m b
forall a b. (a -> b) -> a -> b
$ \State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp ->
        let run :: StreamK m b -> m r
run StreamK m b
x = State StreamK m b
-> (b -> StreamK m b -> m r)
-> (b -> m r)
-> m r
-> StreamK m b
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream State StreamK m b
st b -> StreamK m b -> m r
yld b -> m r
sng m r
stp StreamK m b
x
            stop :: m r
stop = StreamK m b -> m r
run StreamK m b
acc
            single :: a -> m r
single a
a = StreamK m b -> m r
run (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m b -> a -> StreamK m b
step StreamK m b
acc a
a
            yieldk :: a -> StreamK m a -> m r
yieldk a
a StreamK m a
r = StreamK m b -> m r
run (StreamK m b -> m r) -> StreamK m b -> m r
forall a b. (a -> b) -> a -> b
$ StreamK m b -> StreamK m a -> StreamK m b
go (StreamK m b -> a -> StreamK m b
step StreamK m b
acc a
a) StreamK m a
r
         in State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStream (State StreamK m b -> State StreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a (n :: * -> *) b.
State t m a -> State t n b
adaptState State StreamK m b
st) a -> StreamK m a -> m r
yieldk a -> m r
single m r
stop StreamK m a
rest

{-# INLINE reverse #-}
reverse :: StreamK m a -> StreamK m a
reverse :: forall (m :: * -> *) a. StreamK m a -> StreamK m a
reverse = (StreamK m a -> a -> StreamK m a)
-> StreamK m a -> StreamK m a -> StreamK m a
forall (m :: * -> *) b a.
(StreamK m b -> a -> StreamK m b)
-> StreamK m b -> StreamK m a -> StreamK m b
foldlS ((a -> StreamK m a -> StreamK m a)
-> StreamK m a -> a -> StreamK m a
forall a b c. (a -> b -> c) -> b -> a -> c
flip a -> StreamK m a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a -> StreamK m a
cons) StreamK m a
forall (m :: * -> *) a. StreamK m a
nil

------------------------------------------------------------------------------
-- Running effects
------------------------------------------------------------------------------

-- | Run an action before evaluating the stream.
{-# INLINE before #-}
before :: Monad m => m b -> StreamK m a -> StreamK m a
before :: forall (m :: * -> *) b a.
Monad m =>
m b -> StreamK m a -> StreamK m a
before m b
action StreamK m a
stream =
    (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
        m b
action m b -> m r -> m r
forall a b. m a -> m b -> m b
forall (m :: * -> *) a b. Monad m => m a -> m b -> m b
>> State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp StreamK m a
stream

{-# INLINE concatEffect #-}
concatEffect :: Monad m => m (StreamK m a) -> StreamK m a
concatEffect :: forall (m :: * -> *) a. Monad m => m (StreamK m a) -> StreamK m a
concatEffect m (StreamK m a)
action =
    (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
        m (StreamK m a)
action m (StreamK m a) -> (StreamK m a -> m r) -> m r
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp

{-# INLINE concatMapEffect #-}
concatMapEffect :: Monad m => (b -> StreamK m a) -> m b -> StreamK m a
concatMapEffect :: forall (m :: * -> *) b a.
Monad m =>
(b -> StreamK m a) -> m b -> StreamK m a
concatMapEffect b -> StreamK m a
f m b
action =
    (forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall (m :: * -> *) a.
(forall r.
 State StreamK m a
 -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
mkStream ((forall r.
  State StreamK m a
  -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
 -> StreamK m a)
-> (forall r.
    State StreamK m a
    -> (a -> StreamK m a -> m r) -> (a -> m r) -> m r -> m r)
-> StreamK m a
forall a b. (a -> b) -> a -> b
$ \State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp ->
        m b
action m b -> (b -> m r) -> m r
forall a b. m a -> (a -> m b) -> m b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
forall (m :: * -> *) a r.
State StreamK m a
-> (a -> StreamK m a -> m r)
-> (a -> m r)
-> m r
-> StreamK m a
-> m r
foldStreamShared State StreamK m a
st a -> StreamK m a -> m r
yld a -> m r
sng m r
stp (StreamK m a -> m r) -> (b -> StreamK m a) -> b -> m r
forall b c a. (b -> c) -> (a -> b) -> a -> c
. b -> StreamK m a
f

------------------------------------------------------------------------------
-- Stream with a cross product style monad instance
------------------------------------------------------------------------------

-- | A newtype wrapper for the 'StreamK' type adding a cross product style
-- monad instance.
--
-- A 'Monad' bind behaves like a @for@ loop:
--
-- >>> :{
-- Stream.fold Fold.toList $ StreamK.toStream $ StreamK.unCross $ do
--     x <- StreamK.mkCross $ StreamK.fromStream $ Stream.fromList [1,2]
--     -- Perform the following actions for each x in the stream
--     return x
-- :}
-- [1,2]
--
-- Nested monad binds behave like nested @for@ loops:
--
-- >>> :{
-- Stream.fold Fold.toList $ StreamK.toStream $ StreamK.unCross $ do
--     x <- StreamK.mkCross $ StreamK.fromStream $ Stream.fromList [1,2]
--     y <- StreamK.mkCross $ StreamK.fromStream $ Stream.fromList [3,4]
--     -- Perform the following actions for each x, for each y
--     return (x, y)
-- :}
-- [(1,3),(1,4),(2,3),(2,4)]
--
newtype CrossStreamK m a = CrossStreamK {forall (m :: * -> *) a. CrossStreamK m a -> StreamK m a
unCrossStreamK :: StreamK m a}
        deriving ((forall a b. (a -> b) -> CrossStreamK m a -> CrossStreamK m b)
-> (forall a b. a -> CrossStreamK m b -> CrossStreamK m a)
-> Functor (CrossStreamK m)
forall a b. a -> CrossStreamK m b -> CrossStreamK m a
forall a b. (a -> b) -> CrossStreamK m a -> CrossStreamK m b
forall (m :: * -> *) a b.
Monad m =>
a -> CrossStreamK m b -> CrossStreamK m a
forall (m :: * -> *) a b.
Monad m =>
(a -> b) -> CrossStreamK m a -> CrossStreamK m b
forall (f :: * -> *).
(forall a b. (a -> b) -> f a -> f b)
-> (forall a b. a -> f b -> f a) -> Functor f
$cfmap :: forall (m :: * -> *) a b.
Monad m =>
(a -> b) -> CrossStreamK m a -> CrossStreamK m b
fmap :: forall a b. (a -> b) -> CrossStreamK m a -> CrossStreamK m b
$c<$ :: forall (m :: * -> *) a b.
Monad m =>
a -> CrossStreamK m b -> CrossStreamK m a
<$ :: forall a b. a -> CrossStreamK m b -> CrossStreamK m a
Functor, NonEmpty (CrossStreamK m a) -> CrossStreamK m a
CrossStreamK m a -> CrossStreamK m a -> CrossStreamK m a
(CrossStreamK m a -> CrossStreamK m a -> CrossStreamK m a)
-> (NonEmpty (CrossStreamK m a) -> CrossStreamK m a)
-> (forall b.
    Integral b =>
    b -> CrossStreamK m a -> CrossStreamK m a)
-> Semigroup (CrossStreamK m a)
forall b. Integral b => b -> CrossStreamK m a -> CrossStreamK m a
forall a.
(a -> a -> a)
-> (NonEmpty a -> a)
-> (forall b. Integral b => b -> a -> a)
-> Semigroup a
forall (m :: * -> *) a.
NonEmpty (CrossStreamK m a) -> CrossStreamK m a
forall (m :: * -> *) a.
CrossStreamK m a -> CrossStreamK m a -> CrossStreamK m a
forall (m :: * -> *) a b.
Integral b =>
b -> CrossStreamK m a -> CrossStreamK m a
$c<> :: forall (m :: * -> *) a.
CrossStreamK m a -> CrossStreamK m a -> CrossStreamK m a
<> :: CrossStreamK m a -> CrossStreamK m a -> CrossStreamK m a
$csconcat :: forall (m :: * -> *) a.
NonEmpty (CrossStreamK m a) -> CrossStreamK m a
sconcat :: NonEmpty (CrossStreamK m a) -> CrossStreamK m a
$cstimes :: forall (m :: * -> *) a b.
Integral b =>
b -> CrossStreamK m a -> CrossStreamK m a
stimes :: forall b. Integral b => b -> CrossStreamK m a -> CrossStreamK m a
Semigroup, Semigroup (CrossStreamK m a)
CrossStreamK m a
Semigroup (CrossStreamK m a) =>
CrossStreamK m a
-> (CrossStreamK m a -> CrossStreamK m a -> CrossStreamK m a)
-> ([CrossStreamK m a] -> CrossStreamK m a)
-> Monoid (CrossStreamK m a)
[CrossStreamK m a] -> CrossStreamK m a
CrossStreamK m a -> CrossStreamK m a -> CrossStreamK m a
forall a.
Semigroup a =>
a -> (a -> a -> a) -> ([a] -> a) -> Monoid a
forall (m :: * -> *) a. Semigroup (CrossStreamK m a)
forall (m :: * -> *) a. CrossStreamK m a
forall (m :: * -> *) a. [CrossStreamK m a] -> CrossStreamK m a
forall (m :: * -> *) a.
CrossStreamK m a -> CrossStreamK m a -> CrossStreamK m a
$cmempty :: forall (m :: * -> *) a. CrossStreamK m a
mempty :: CrossStreamK m a
$cmappend :: forall (m :: * -> *) a.
CrossStreamK m a -> CrossStreamK m a -> CrossStreamK m a
mappend :: CrossStreamK m a -> CrossStreamK m a -> CrossStreamK m a
$cmconcat :: forall (m :: * -> *) a. [CrossStreamK m a] -> CrossStreamK m a
mconcat :: [CrossStreamK m a] -> CrossStreamK m a
Monoid, (forall m. Monoid m => CrossStreamK m m -> m)
-> (forall m a. Monoid m => (a -> m) -> CrossStreamK m a -> m)
-> (forall m a. Monoid m => (a -> m) -> CrossStreamK m a -> m)
-> (forall a b. (a -> b -> b) -> b -> CrossStreamK m a -> b)
-> (forall a b. (a -> b -> b) -> b -> CrossStreamK m a -> b)
-> (forall b a. (b -> a -> b) -> b -> CrossStreamK m a -> b)
-> (forall b a. (b -> a -> b) -> b -> CrossStreamK m a -> b)
-> (forall a. (a -> a -> a) -> CrossStreamK m a -> a)
-> (forall a. (a -> a -> a) -> CrossStreamK m a -> a)
-> (forall a. CrossStreamK m a -> [a])
-> (forall a. CrossStreamK m a -> Bool)
-> (forall a. CrossStreamK m a -> Int)
-> (forall a. Eq a => a -> CrossStreamK m a -> Bool)
-> (forall a. Ord a => CrossStreamK m a -> a)
-> (forall a. Ord a => CrossStreamK m a -> a)
-> (forall a. Num a => CrossStreamK m a -> a)
-> (forall a. Num a => CrossStreamK m a -> a)
-> Foldable (CrossStreamK m)
forall a. Eq a => a -> CrossStreamK m a -> Bool
forall a. Num a => CrossStreamK m a -> a
forall a. Ord a => CrossStreamK m a -> a
forall m. Monoid m => CrossStreamK m m -> m
forall a. CrossStreamK m a -> Bool
forall a. CrossStreamK m a -> Int
forall a. CrossStreamK m a -> [a]
forall a. (a -> a -> a) -> CrossStreamK m a -> a
forall m a. Monoid m => (a -> m) -> CrossStreamK m a -> m
forall b a. (b -> a -> b) -> b -> CrossStreamK m a -> b
forall a b. (a -> b -> b) -> b -> CrossStreamK m a -> b
forall (m :: * -> *) a.
(Foldable m, Monad m, Eq a) =>
a -> CrossStreamK m a -> Bool
forall (m :: * -> *) a.
(Foldable m, Monad m, Num a) =>
CrossStreamK m a -> a
forall (m :: * -> *) a.
(Foldable m, Monad m, Ord a) =>
CrossStreamK m a -> a
forall (m :: * -> *) m.
(Foldable m, Monad m, Monoid m) =>
CrossStreamK m m -> m
forall (m :: * -> *) a.
(Foldable m, Monad m) =>
CrossStreamK m a -> Bool
forall (m :: * -> *) a.
(Foldable m, Monad m) =>
CrossStreamK m a -> Int
forall (m :: * -> *) a.
(Foldable m, Monad m) =>
CrossStreamK m a -> [a]
forall (m :: * -> *) a.
(Foldable m, Monad m) =>
(a -> a -> a) -> CrossStreamK m a -> a
forall (m :: * -> *) m a.
(Foldable m, Monad m, Monoid m) =>
(a -> m) -> CrossStreamK m a -> m
forall (m :: * -> *) b a.
(Foldable m, Monad m) =>
(b -> a -> b) -> b -> CrossStreamK m a -> b
forall (m :: * -> *) a b.
(Foldable m, Monad m) =>
(a -> b -> b) -> b -> CrossStreamK m a -> b
forall (t :: * -> *).
(forall m. Monoid m => t m -> m)
-> (forall m a. Monoid m => (a -> m) -> t a -> m)
-> (forall m a. Monoid m => (a -> m) -> t a -> m)
-> (forall a b. (a -> b -> b) -> b -> t a -> b)
-> (forall a b. (a -> b -> b) -> b -> t a -> b)
-> (forall b a. (b -> a -> b) -> b -> t a -> b)
-> (forall b a. (b -> a -> b) -> b -> t a -> b)
-> (forall a. (a -> a -> a) -> t a -> a)
-> (forall a. (a -> a -> a) -> t a -> a)
-> (forall a. t a -> [a])
-> (forall a. t a -> Bool)
-> (forall a. t a -> Int)
-> (forall a. Eq a => a -> t a -> Bool)
-> (forall a. Ord a => t a -> a)
-> (forall a. Ord a => t a -> a)
-> (forall a. Num a => t a -> a)
-> (forall a. Num a => t a -> a)
-> Foldable t
$cfold :: forall (m :: * -> *) m.
(Foldable m, Monad m, Monoid m) =>
CrossStreamK m m -> m
fold :: forall m. Monoid m => CrossStreamK m m -> m
$cfoldMap :: forall (m :: * -> *) m a.
(Foldable m, Monad m, Monoid m) =>
(a -> m) -> CrossStreamK m a -> m
foldMap :: forall m a. Monoid m => (a -> m) -> CrossStreamK m a -> m
$cfoldMap' :: forall (m :: * -> *) m a.
(Foldable m, Monad m, Monoid m) =>
(a -> m) -> CrossStreamK m a -> m
foldMap' :: forall m a. Monoid m => (a -> m) -> CrossStreamK m a -> m
$cfoldr :: forall (m :: * -> *) a b.
(Foldable m, Monad m) =>
(a -> b -> b) -> b -> CrossStreamK m a -> b
foldr :: forall a b. (a -> b -> b) -> b -> CrossStreamK m a -> b
$cfoldr' :: forall (m :: * -> *) a b.
(Foldable m, Monad m) =>
(a -> b -> b) -> b -> CrossStreamK m a -> b
foldr' :: forall a b. (a -> b -> b) -> b -> CrossStreamK m a -> b
$cfoldl :: forall (m :: * -> *) b a.
(Foldable m, Monad m) =>
(b -> a -> b) -> b -> CrossStreamK m a -> b
foldl :: forall b a. (b -> a -> b) -> b -> CrossStreamK m a -> b
$cfoldl' :: forall (m :: * -> *) b a.
(Foldable m, Monad m) =>
(b -> a -> b) -> b -> CrossStreamK m a -> b
foldl' :: forall b a. (b -> a -> b) -> b -> CrossStreamK m a -> b
$cfoldr1 :: forall (m :: * -> *) a.
(Foldable m, Monad m) =>
(a -> a -> a) -> CrossStreamK m a -> a
foldr1 :: forall a. (a -> a -> a) -> CrossStreamK m a -> a
$cfoldl1 :: forall (m :: * -> *) a.
(Foldable m, Monad m) =>
(a -> a -> a) -> CrossStreamK m a -> a
foldl1 :: forall a. (a -> a -> a) -> CrossStreamK m a -> a
$ctoList :: forall (m :: * -> *) a.
(Foldable m, Monad m) =>
CrossStreamK m a -> [a]
toList :: forall a. CrossStreamK m a -> [a]
$cnull :: forall (m :: * -> *) a.
(Foldable m, Monad m) =>
CrossStreamK m a -> Bool
null :: forall a. CrossStreamK m a -> Bool
$clength :: forall (m :: * -> *) a.
(Foldable m, Monad m) =>
CrossStreamK m a -> Int
length :: forall a. CrossStreamK m a -> Int
$celem :: forall (m :: * -> *) a.
(Foldable m, Monad m, Eq a) =>
a -> CrossStreamK m a -> Bool
elem :: forall a. Eq a => a -> CrossStreamK m a -> Bool
$cmaximum :: forall (m :: * -> *) a.
(Foldable m, Monad m, Ord a) =>
CrossStreamK m a -> a
maximum :: forall a. Ord a => CrossStreamK m a -> a
$cminimum :: forall (m :: * -> *) a.
(Foldable m, Monad m, Ord a) =>
CrossStreamK m a -> a
minimum :: forall a. Ord a => CrossStreamK m a -> a
$csum :: forall (m :: * -> *) a.
(Foldable m, Monad m, Num a) =>
CrossStreamK m a -> a
sum :: forall a. Num a => CrossStreamK m a -> a
$cproduct :: forall (m :: * -> *) a.
(Foldable m, Monad m, Num a) =>
CrossStreamK m a -> a
product :: forall a. Num a => CrossStreamK m a -> a
Foldable)

-- | Wrap the 'StreamK' type in a 'CrossStreamK' newtype to enable cross
-- product style applicative and monad instances.
--
-- This is a type level operation with no runtime overhead.
{-# INLINE mkCross #-}
mkCross :: StreamK m a -> CrossStreamK m a
mkCross :: forall (m :: * -> *) a. StreamK m a -> CrossStreamK m a
mkCross = StreamK m a -> CrossStreamK m a
forall (m :: * -> *) a. StreamK m a -> CrossStreamK m a
CrossStreamK

-- | Unwrap the 'StreamK' type from 'CrossStreamK' newtype.
--
-- This is a type level operation with no runtime overhead.
{-# INLINE unCross #-}
unCross :: CrossStreamK m a -> StreamK m a
unCross :: forall (m :: * -> *) a. CrossStreamK m a -> StreamK m a
unCross = CrossStreamK m a -> StreamK m a
forall (m :: * -> *) a. CrossStreamK m a -> StreamK m a
unCrossStreamK

-- Pure (Identity monad) stream instances
deriving instance Traversable (CrossStreamK Identity)
deriving instance IsList (CrossStreamK Identity a)
deriving instance (a ~ Char) => IsString (CrossStreamK Identity a)
-- deriving instance Eq a => Eq (CrossStreamK Identity a)
-- deriving instance Ord a => Ord (CrossStreamK Identity a)

-- Do not use automatic derivation for this to show as "fromList" rather than
-- "fromList Identity".
instance Show a => Show (CrossStreamK Identity a) where
    {-# INLINE show #-}
    show :: CrossStreamK Identity a -> String
show (CrossStreamK StreamK Identity a
xs) = StreamK Identity a -> String
forall a. Show a => a -> String
show StreamK Identity a
xs

instance Read a => Read (CrossStreamK Identity a) where
    {-# INLINE readPrec #-}
    readPrec :: ReadPrec (CrossStreamK Identity a)
readPrec = (StreamK Identity a -> CrossStreamK Identity a)
-> ReadPrec (StreamK Identity a)
-> ReadPrec (CrossStreamK Identity a)
forall a b. (a -> b) -> ReadPrec a -> ReadPrec b
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap StreamK Identity a -> CrossStreamK Identity a
forall (m :: * -> *) a. StreamK m a -> CrossStreamK m a
CrossStreamK ReadPrec (StreamK Identity a)
forall a. Read a => ReadPrec a
readPrec

------------------------------------------------------------------------------
-- Applicative
------------------------------------------------------------------------------

-- Note: we need to define all the typeclass operations because we want to
-- INLINE them.
instance Monad m => Applicative (CrossStreamK m) where
    {-# INLINE pure #-}
    pure :: forall a. a -> CrossStreamK m a
pure a
x = StreamK m a -> CrossStreamK m a
forall (m :: * -> *) a. StreamK m a -> CrossStreamK m a
CrossStreamK (a -> StreamK m a
forall a (m :: * -> *). a -> StreamK m a
fromPure a
x)

    {-# INLINE (<*>) #-}
    (CrossStreamK StreamK m (a -> b)
s1) <*> :: forall a b.
CrossStreamK m (a -> b) -> CrossStreamK m a -> CrossStreamK m b
<*> (CrossStreamK StreamK m a
s2) =
        StreamK m b -> CrossStreamK m b
forall (m :: * -> *) a. StreamK m a -> CrossStreamK m a
CrossStreamK (StreamK m (a -> b) -> StreamK m a -> StreamK m b
forall (m :: * -> *) a b.
StreamK m (a -> b) -> StreamK m a -> StreamK m b
crossApply StreamK m (a -> b)
s1 StreamK m a
s2)

    {-# INLINE liftA2 #-}
    liftA2 :: forall a b c.
(a -> b -> c)
-> CrossStreamK m a -> CrossStreamK m b -> CrossStreamK m c
liftA2 a -> b -> c
f CrossStreamK m a
x = CrossStreamK m (b -> c) -> CrossStreamK m b -> CrossStreamK m c
forall a b.
CrossStreamK m (a -> b) -> CrossStreamK m a -> CrossStreamK m b
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
(<*>) ((a -> b -> c) -> CrossStreamK m a -> CrossStreamK m (b -> c)
forall a b. (a -> b) -> CrossStreamK m a -> CrossStreamK m b
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap a -> b -> c
f CrossStreamK m a
x)

    {-# INLINE (*>) #-}
    (CrossStreamK StreamK m a
s1) *> :: forall a b.
CrossStreamK m a -> CrossStreamK m b -> CrossStreamK m b
*> (CrossStreamK StreamK m b
s2) =
        StreamK m b -> CrossStreamK m b
forall (m :: * -> *) a. StreamK m a -> CrossStreamK m a
CrossStreamK (StreamK m a -> StreamK m b -> StreamK m b
forall (m :: * -> *) a b. StreamK m a -> StreamK m b -> StreamK m b
crossApplySnd StreamK m a
s1 StreamK m b
s2)

    {-# INLINE (<*) #-}
    (CrossStreamK StreamK m a
s1) <* :: forall a b.
CrossStreamK m a -> CrossStreamK m b -> CrossStreamK m a
<* (CrossStreamK StreamK m b
s2) =
        StreamK m a -> CrossStreamK m a
forall (m :: * -> *) a. StreamK m a -> CrossStreamK m a
CrossStreamK (StreamK m a -> StreamK m b -> StreamK m a
forall (m :: * -> *) a b. StreamK m a -> StreamK m b -> StreamK m a
crossApplyFst StreamK m a
s1 StreamK m b
s2)

------------------------------------------------------------------------------
-- Monad
------------------------------------------------------------------------------

instance Monad m => Monad (CrossStreamK m) where
    return :: forall a. a -> CrossStreamK m a
return = a -> CrossStreamK m a
forall a. a -> CrossStreamK m a
forall (f :: * -> *) a. Applicative f => a -> f a
pure

    -- Benchmarks better with CPS bind and pure:
    -- Prime sieve (25x)
    -- n binds, breakAfterSome, filterAllIn, state transformer (~2x)
    --
    {-# INLINE (>>=) #-}
    >>= :: forall a b.
CrossStreamK m a -> (a -> CrossStreamK m b) -> CrossStreamK m b
(>>=) (CrossStreamK StreamK m a
m) a -> CrossStreamK m b
f =
        StreamK m b -> CrossStreamK m b
forall (m :: * -> *) a. StreamK m a -> CrossStreamK m a
CrossStreamK ((StreamK m b -> StreamK m b -> StreamK m b)
-> StreamK m a -> (a -> StreamK m b) -> StreamK m b
forall (m :: * -> *) b a.
(StreamK m b -> StreamK m b -> StreamK m b)
-> StreamK m a -> (a -> StreamK m b) -> StreamK m b
bindWith StreamK m b -> StreamK m b -> StreamK m b
forall (m :: * -> *) a. StreamK m a -> StreamK m a -> StreamK m a
append StreamK m a
m (CrossStreamK m b -> StreamK m b
forall (m :: * -> *) a. CrossStreamK m a -> StreamK m a
unCrossStreamK (CrossStreamK m b -> StreamK m b)
-> (a -> CrossStreamK m b) -> a -> StreamK m b
forall b c a. (b -> c) -> (a -> b) -> a -> c
. a -> CrossStreamK m b
f))

    {-# INLINE (>>) #-}
    >> :: forall a b.
CrossStreamK m a -> CrossStreamK m b -> CrossStreamK m b
(>>) = CrossStreamK m a -> CrossStreamK m b -> CrossStreamK m b
forall a b.
CrossStreamK m a -> CrossStreamK m b -> CrossStreamK m b
forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
(*>)

------------------------------------------------------------------------------
-- Transformers
------------------------------------------------------------------------------

instance (MonadIO m) => MonadIO (CrossStreamK m) where
    liftIO :: forall a. IO a -> CrossStreamK m a
liftIO IO a
x = StreamK m a -> CrossStreamK m a
forall (m :: * -> *) a. StreamK m a -> CrossStreamK m a
CrossStreamK (m a -> StreamK m a
forall (m :: * -> *) a. Monad m => m a -> StreamK m a
fromEffect (m a -> StreamK m a) -> m a -> StreamK m a
forall a b. (a -> b) -> a -> b
$ IO a -> m a
forall a. IO a -> m a
forall (m :: * -> *) a. MonadIO m => IO a -> m a
liftIO IO a
x)

instance MonadTrans CrossStreamK where
    {-# INLINE lift #-}
    lift :: forall (m :: * -> *) a. Monad m => m a -> CrossStreamK m a
lift m a
x = StreamK m a -> CrossStreamK m a
forall (m :: * -> *) a. StreamK m a -> CrossStreamK m a
CrossStreamK (m a -> StreamK m a
forall (m :: * -> *) a. Monad m => m a -> StreamK m a
fromEffect m a
x)

instance (MonadThrow m) => MonadThrow (CrossStreamK m) where
    throwM :: forall e a. (HasCallStack, Exception e) => e -> CrossStreamK m a
throwM = m a -> CrossStreamK m a
forall (m :: * -> *) a. Monad m => m a -> CrossStreamK m a
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift (m a -> CrossStreamK m a) -> (e -> m a) -> e -> CrossStreamK m a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. e -> m a
forall e a. (HasCallStack, Exception e) => e -> m a
forall (m :: * -> *) e a.
(MonadThrow m, HasCallStack, Exception e) =>
e -> m a
throwM