Safe Haskell	Safe
Language	Haskell2010

Piped.Internal

Contents

Pipe
Continuations
Miscellania

Description

The internal API and core datatypes of Pipe.

Synopsis

newtype Pipe i o m a = Pipe {
- unPipe :: forall r. (Await i m r -> Yield o m r -> a -> m r) -> Await i m r -> Yield o m r -> m r
}
await :: Monad m => Pipe i o m (Maybe i)
yield :: o -> Pipe i o m ()
runPipe :: Monad m => Pipe () Void m r -> m r
leftover :: i -> Pipe i o m ()
newtype Await i m a = Await {
- unAwait :: Await' i m a
}
data Yield i m a = Yield {
- terminate :: m a
- unYield :: Yield' i m a
}
type Await' i m a = Yield i m a -> m a
type Yield' i m a = i -> Await i m a -> m a
runAwait :: Await i m a -> m a -> Yield' i m a -> m a
runYield :: Yield i m a -> i -> Await' i m a -> m a
termLeft :: Await i m a
termRight :: Yield i1 m a -> Yield i2 m a
voidRight :: Yield Void m a
addLeftover :: i -> Await i m a -> Await i m a
data Void
fix1 :: a -> ((a -> b) -> a -> b) -> b
fix2 :: a -> b -> ((a -> b -> c) -> a -> b -> c) -> c

Pipe

Piped is implemented using a type of codensity transform, that uses left and right continuations, rather than sum types, to propagate state transitions.

newtype Pipe i o m a Source #

The Pipe datatype, that represents a stage in a pipeline with inputs of type i and outputs of type o.

Constructors

Pipe
Fields unPipe :: forall r. (Await i m r -> Yield o m r -> a -> m r) -> Await i m r -> Yield o m r -> m r

Instances

MonadState s m => MonadState s (Pipe i o m) Source #
Instance details Defined in Piped.Internal Methods get :: Pipe i o m s # put :: s -> Pipe i o m () # state :: (s -> (a, s)) -> Pipe i o m a #
MonadReader r m => MonadReader r (Pipe i o m) Source #
Instance details Defined in Piped.Internal Methods ask :: Pipe i o m r # local :: (r -> r) -> Pipe i o m a -> Pipe i o m a # reader :: (r -> a) -> Pipe i o m a #
MonadTrans (Pipe i o) Source #
Instance details Defined in Piped.Internal Methods lift :: Monad m => m a -> Pipe i o m a #
Monad m => Monad (Pipe i o m) Source #
Instance details Defined in Piped.Internal Methods (>>=) :: Pipe i o m a -> (a -> Pipe i o m b) -> Pipe i o m b # (>>) :: Pipe i o m a -> Pipe i o m b -> Pipe i o m b # return :: a -> Pipe i o m a # fail :: String -> Pipe i o m a #
Monad m => Functor (Pipe i o m) Source #
Instance details Defined in Piped.Internal Methods fmap :: (a -> b) -> Pipe i o m a -> Pipe i o m b # (<$) :: a -> Pipe i o m b -> Pipe i o m a #
Monad m => Applicative (Pipe i o m) Source #
Instance details Defined in Piped.Internal Methods pure :: a -> Pipe i o m a # (<>) :: Pipe i o m (a -> b) -> Pipe i o m a -> Pipe i o m b # liftA2 :: (a -> b -> c) -> Pipe i o m a -> Pipe i o m b -> Pipe i o m c # (>) :: Pipe i o m a -> Pipe i o m b -> Pipe i o m b # (<*) :: Pipe i o m a -> Pipe i o m b -> Pipe i o m a #
MonadIO m => MonadIO (Pipe i o m) Source #
Instance details Defined in Piped.Internal Methods liftIO :: IO a -> Pipe i o m a #
Monad m => Semigroup (Pipe i o m a) Source #
Instance details Defined in Piped.Internal Methods (<>) :: Pipe i o m a -> Pipe i o m a -> Pipe i o m a # sconcat :: NonEmpty (Pipe i o m a) -> Pipe i o m a # stimes :: Integral b => b -> Pipe i o m a -> Pipe i o m a #
Monad m => Monoid (Pipe i o m ()) Source #
Instance details Defined in Piped.Internal Methods mempty :: Pipe i o m () # mappend :: Pipe i o m () -> Pipe i o m () -> Pipe i o m () # mconcat :: [Pipe i o m ()] -> Pipe i o m () #

await :: Monad m => Pipe i o m (Maybe i) Source #

Await a value. Nothing indicates that there are no more values.

yield :: o -> Pipe i o m () Source #

Yield a value to downstream.

runPipe :: Monad m => Pipe () Void m r -> m r Source #

Run pipe to completion.

leftover :: i -> Pipe i o m () Source #

Push a value back into the incoming pipeline

Continuations

The state of a pipeline is encoded in a recursive data structure (Await / Yield) which holds continuations that promise a final return value of r.

newtype Await i m a Source #

The upstream continuation; holds a callback that provides a value.

Constructors

Await
Fields unAwait :: Await' i m a

data Yield i m a Source #

The downstream continuation; holds a callback that accepts a value, plus a default return value in case there is no more input.

Constructors

Yield
Fields terminate :: m a unYield :: Yield' i m a

type Await' i m a = Yield i m a -> m a Source #

The type of an upstream continuation

type Yield' i m a = i -> Await i m a -> m a Source #

The type of a downstream continuation

runAwait :: Await i m a -> m a -> Yield' i m a -> m a Source #

Run an Await

runYield :: Yield i m a -> i -> Await' i m a -> m a Source #

Run a Yield

termLeft :: Await i m a Source #

An Await that terminates when called.

termRight :: Yield i1 m a -> Yield i2 m a Source #

A Yield that terminates when called.

voidRight :: Yield Void m a Source #

A Void output

addLeftover :: i -> Await i m a -> Await i m a Source #

Wrap an Await with a leftover value

data Void #

Uninhabited data type

Since: base-4.8.0.0

Instances

Eq Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods (==) :: Void -> Void -> Bool # (/=) :: Void -> Void -> Bool #
Data Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Void -> c Void # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Void # toConstr :: Void -> Constr # dataTypeOf :: Void -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Void) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Void) # gmapT :: (forall b. Data b => b -> b) -> Void -> Void # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Void -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Void -> r # gmapQ :: (forall d. Data d => d -> u) -> Void -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Void -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Void -> m Void # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Void -> m Void # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Void -> m Void #
Ord Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods compare :: Void -> Void -> Ordering # (<) :: Void -> Void -> Bool # (<=) :: Void -> Void -> Bool # (>) :: Void -> Void -> Bool # (>=) :: Void -> Void -> Bool # max :: Void -> Void -> Void # min :: Void -> Void -> Void #
Read Void	Reading a `Void` value is always a parse error, considering `Void` as a data type with no constructors. Since: base-4.8.0.0
Instance details Defined in Data.Void Methods readsPrec :: Int -> ReadS Void # readList :: ReadS [Void] # readPrec :: ReadPrec Void # readListPrec :: ReadPrec [Void] #
Show Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods showsPrec :: Int -> Void -> ShowS # show :: Void -> String # showList :: [Void] -> ShowS #
Ix Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods range :: (Void, Void) -> [Void] # index :: (Void, Void) -> Void -> Int # unsafeIndex :: (Void, Void) -> Void -> Int inRange :: (Void, Void) -> Void -> Bool # rangeSize :: (Void, Void) -> Int # unsafeRangeSize :: (Void, Void) -> Int
Generic Void
Instance details Defined in Data.Void Associated Types type Rep Void :: Type -> Type # Methods from :: Void -> Rep Void x # to :: Rep Void x -> Void #
Semigroup Void	Since: base-4.9.0.0
Instance details Defined in Data.Void Methods (<>) :: Void -> Void -> Void # sconcat :: NonEmpty Void -> Void # stimes :: Integral b => b -> Void -> Void #
Exception Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods toException :: Void -> SomeException # fromException :: SomeException -> Maybe Void # displayException :: Void -> String #
type Rep Void	Since: base-4.8.0.0
Instance details Defined in Data.Void type Rep Void = D1 (MetaData "Void" "Data.Void" "base" False) (V1 :: Type -> Type)

Miscellania

fix1 :: a -> ((a -> b) -> a -> b) -> b Source #

fix2 :: a -> b -> ((a -> b -> c) -> a -> b -> c) -> c Source #