rhine-1.0: Functional Reactive Programming with type-level clocks
Safe HaskellSafe-Inferred
LanguageHaskell2010

FRP.Rhine.ClSF.Core

Description

The core functionality of clocked signal functions, supplying the type of clocked signal functions itself (ClSF), behaviours (clock-independent/polymorphic signal functions), and basic constructions of ClSFs that may use awareness of time as an effect.

Synopsis

Documentation

type BehaviorF m time a b = BehaviourF m time a b Source #

Compatibility to U.S. american spelling.

type BehaviourF m time a b = forall cl. time ~ Time cl => ClSF m cl a b Source #

A (side-effectful) behaviour function is a time-aware synchronous stream function that doesn't depend on a particular clock. time denotes the TimeDomain.

type Behavior m time a = Behaviour m time a Source #

Compatibility to U.S. american spelling.

type Behaviour m time a = forall cl. time ~ Time cl => ClSignal m cl a Source #

A (side-effectful) behaviour is a time-aware stream that doesn't depend on a particular clock. time denotes the TimeDomain.

type ClSignal m cl a = forall arbitrary. ClSF m cl arbitrary a Source #

A clocked signal is a ClSF with no input required. It produces its output on its own.

type ClSF m cl a b = MSF (ReaderT (TimeInfo cl) m) a b Source #

A (synchronous, clocked) monadic stream function with the additional side effect of being time-aware, that is, reading the current TimeInfo of the clock cl.

hoistClSF :: (Monad m1, Monad m2) => (forall c. m1 c -> m2 c) -> ClSF m1 cl a b -> ClSF m2 cl a b Source #

Hoist a ClSF along a monad morphism.

hoistClSFAndClock :: (Monad m1, Monad m2) => (forall c. m1 c -> m2 c) -> ClSF m1 cl a b -> ClSF m2 (HoistClock m1 m2 cl) a b Source #

Hoist a ClSF and its clock along a monad morphism.

liftClSF :: (Monad m, MonadTrans t, Monad (t m)) => ClSF m cl a b -> ClSF (t m) cl a b Source #

Lift a ClSF into a monad transformer.

liftClSFAndClock :: (Monad m, MonadTrans t, Monad (t m)) => ClSF m cl a b -> ClSF (t m) (LiftClock m t cl) a b Source #

Lift a ClSF and its clock into a monad transformer.

timeless :: Monad m => MSF m a b -> ClSF m cl a b Source #

A monadic stream function without dependency on time is a ClSF for any clock.

arrMCl :: Monad m => (a -> m b) -> ClSF m cl a b Source #

Utility to lift Kleisli arrows directly to ClSFs.

constMCl :: Monad m => m b -> ClSF m cl a b Source #

Version without input.

mapMaybe :: Monad m => ClSF m cl a b -> ClSF m cl (Maybe a) (Maybe b) Source #

Call a ClSF every time the input is 'Just a'.

Caution: This will not change the time differences since the last tick. For example, while integrate 1 is approximately the same as timeInfoOf sinceInit, mapMaybe $ integrate 1 is very different from mapMaybe $ timeInfoOf sinceInit. The former only integrates when the input is Just 1, whereas the latter always returns the correct time since initialisation.

newtype Kleisli (m :: Type -> Type) a b #

Kleisli arrows of a monad.

Constructors

Kleisli 

Fields

Instances

Instances details
Monad m => Category (Kleisli m :: Type -> Type -> TYPE LiftedRep)

Since: base-3.0

Instance details

Defined in Control.Arrow

Methods

id :: forall (a :: k). Kleisli m a a #

(.) :: forall (b :: k) (c :: k) (a :: k). Kleisli m b c -> Kleisli m a b -> Kleisli m a c #

Generic1 (Kleisli m a :: Type -> TYPE LiftedRep) 
Instance details

Defined in Control.Arrow

Associated Types

type Rep1 (Kleisli m a) :: k -> Type #

Methods

from1 :: forall (a0 :: k). Kleisli m a a0 -> Rep1 (Kleisli m a) a0 #

to1 :: forall (a0 :: k). Rep1 (Kleisli m a) a0 -> Kleisli m a a0 #

Monad m => Arrow (Kleisli m)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

arr :: (b -> c) -> Kleisli m b c #

first :: Kleisli m b c -> Kleisli m (b, d) (c, d) #

second :: Kleisli m b c -> Kleisli m (d, b) (d, c) #

(***) :: Kleisli m b c -> Kleisli m b' c' -> Kleisli m (b, b') (c, c') #

(&&&) :: Kleisli m b c -> Kleisli m b c' -> Kleisli m b (c, c') #

Monad m => ArrowApply (Kleisli m)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

app :: Kleisli m (Kleisli m b c, b) c #

Monad m => ArrowChoice (Kleisli m)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

left :: Kleisli m b c -> Kleisli m (Either b d) (Either c d) #

right :: Kleisli m b c -> Kleisli m (Either d b) (Either d c) #

(+++) :: Kleisli m b c -> Kleisli m b' c' -> Kleisli m (Either b b') (Either c c') #

(|||) :: Kleisli m b d -> Kleisli m c d -> Kleisli m (Either b c) d #

MonadFix m => ArrowLoop (Kleisli m)

Beware that for many monads (those for which the >>= operation is strict) this instance will not satisfy the right-tightening law required by the ArrowLoop class.

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

loop :: Kleisli m (b, d) (c, d) -> Kleisli m b c #

MonadPlus m => ArrowPlus (Kleisli m)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

(<+>) :: Kleisli m b c -> Kleisli m b c -> Kleisli m b c #

MonadPlus m => ArrowZero (Kleisli m)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

zeroArrow :: Kleisli m b c #

Alternative m => Alternative (Kleisli m a)

Since: base-4.14.0.0

Instance details

Defined in Control.Arrow

Methods

empty :: Kleisli m a a0 #

(<|>) :: Kleisli m a a0 -> Kleisli m a a0 -> Kleisli m a a0 #

some :: Kleisli m a a0 -> Kleisli m a [a0] #

many :: Kleisli m a a0 -> Kleisli m a [a0] #

Applicative m => Applicative (Kleisli m a)

Since: base-4.14.0.0

Instance details

Defined in Control.Arrow

Methods

pure :: a0 -> Kleisli m a a0 #

(<*>) :: Kleisli m a (a0 -> b) -> Kleisli m a a0 -> Kleisli m a b #

liftA2 :: (a0 -> b -> c) -> Kleisli m a a0 -> Kleisli m a b -> Kleisli m a c #

(*>) :: Kleisli m a a0 -> Kleisli m a b -> Kleisli m a b #

(<*) :: Kleisli m a a0 -> Kleisli m a b -> Kleisli m a a0 #

Functor m => Functor (Kleisli m a)

Since: base-4.14.0.0

Instance details

Defined in Control.Arrow

Methods

fmap :: (a0 -> b) -> Kleisli m a a0 -> Kleisli m a b #

(<$) :: a0 -> Kleisli m a b -> Kleisli m a a0 #

Monad m => Monad (Kleisli m a)

Since: base-4.14.0.0

Instance details

Defined in Control.Arrow

Methods

(>>=) :: Kleisli m a a0 -> (a0 -> Kleisli m a b) -> Kleisli m a b #

(>>) :: Kleisli m a a0 -> Kleisli m a b -> Kleisli m a b #

return :: a0 -> Kleisli m a a0 #

MonadPlus m => MonadPlus (Kleisli m a)

Since: base-4.14.0.0

Instance details

Defined in Control.Arrow

Methods

mzero :: Kleisli m a a0 #

mplus :: Kleisli m a a0 -> Kleisli m a a0 -> Kleisli m a a0 #

Generic (Kleisli m a b) 
Instance details

Defined in Control.Arrow

Associated Types

type Rep (Kleisli m a b) :: Type -> Type #

Methods

from :: Kleisli m a b -> Rep (Kleisli m a b) x #

to :: Rep (Kleisli m a b) x -> Kleisli m a b #

type Rep1 (Kleisli m a :: Type -> TYPE LiftedRep)

Since: base-4.14.0.0

Instance details

Defined in Control.Arrow

type Rep1 (Kleisli m a :: Type -> TYPE LiftedRep) = D1 ('MetaData "Kleisli" "Control.Arrow" "base" 'True) (C1 ('MetaCons "Kleisli" 'PrefixI 'True) (S1 ('MetaSel ('Just "runKleisli") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) ((FUN 'Many a :: TYPE LiftedRep -> Type) :.: Rec1 m)))
type Rep (Kleisli m a b)

Since: base-4.14.0.0

Instance details

Defined in Control.Arrow

type Rep (Kleisli m a b) = D1 ('MetaData "Kleisli" "Control.Arrow" "base" 'True) (C1 ('MetaCons "Kleisli" 'PrefixI 'True) (S1 ('MetaSel ('Just "runKleisli") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (a -> m b))))

class Arrow a => ArrowZero (a :: TYPE LiftedRep -> TYPE LiftedRep -> Type) where #

Methods

zeroArrow :: a b c #

Instances

Instances details
MonadPlus m => ArrowZero (Kleisli m)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

zeroArrow :: Kleisli m b c #

(ArrowZero p, ArrowZero q) => ArrowZero (Product p q) 
Instance details

Defined in Data.Bifunctor.Product

Methods

zeroArrow :: Product p q b c #

(Applicative f, ArrowZero p) => ArrowZero (Tannen f p) 
Instance details

Defined in Data.Bifunctor.Tannen

Methods

zeroArrow :: Tannen f p b c #

class ArrowZero a => ArrowPlus (a :: TYPE LiftedRep -> TYPE LiftedRep -> Type) where #

A monoid on arrows.

Methods

(<+>) :: a b c -> a b c -> a b c infixr 5 #

An associative operation with identity zeroArrow.

Instances

Instances details
MonadPlus m => ArrowPlus (Kleisli m)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

(<+>) :: Kleisli m b c -> Kleisli m b c -> Kleisli m b c #

(ArrowPlus p, ArrowPlus q) => ArrowPlus (Product p q) 
Instance details

Defined in Data.Bifunctor.Product

Methods

(<+>) :: Product p q b c -> Product p q b c -> Product p q b c #

(Applicative f, ArrowPlus p) => ArrowPlus (Tannen f p) 
Instance details

Defined in Data.Bifunctor.Tannen

Methods

(<+>) :: Tannen f p b c -> Tannen f p b c -> Tannen f p b c #

newtype ArrowMonad (a :: Type -> Type -> Type) b #

The ArrowApply class is equivalent to Monad: any monad gives rise to a Kleisli arrow, and any instance of ArrowApply defines a monad.

Constructors

ArrowMonad (a () b) 

Instances

Instances details
ArrowPlus a => Alternative (ArrowMonad a)

Since: base-4.6.0.0

Instance details

Defined in Control.Arrow

Methods

empty :: ArrowMonad a a0 #

(<|>) :: ArrowMonad a a0 -> ArrowMonad a a0 -> ArrowMonad a a0 #

some :: ArrowMonad a a0 -> ArrowMonad a [a0] #

many :: ArrowMonad a a0 -> ArrowMonad a [a0] #

Arrow a => Applicative (ArrowMonad a)

Since: base-4.6.0.0

Instance details

Defined in Control.Arrow

Methods

pure :: a0 -> ArrowMonad a a0 #

(<*>) :: ArrowMonad a (a0 -> b) -> ArrowMonad a a0 -> ArrowMonad a b #

liftA2 :: (a0 -> b -> c) -> ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a c #

(*>) :: ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a b #

(<*) :: ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a a0 #

Arrow a => Functor (ArrowMonad a)

Since: base-4.6.0.0

Instance details

Defined in Control.Arrow

Methods

fmap :: (a0 -> b) -> ArrowMonad a a0 -> ArrowMonad a b #

(<$) :: a0 -> ArrowMonad a b -> ArrowMonad a a0 #

ArrowApply a => Monad (ArrowMonad a)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

(>>=) :: ArrowMonad a a0 -> (a0 -> ArrowMonad a b) -> ArrowMonad a b #

(>>) :: ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a b #

return :: a0 -> ArrowMonad a a0 #

(ArrowApply a, ArrowPlus a) => MonadPlus (ArrowMonad a)

Since: base-4.6.0.0

Instance details

Defined in Control.Arrow

Methods

mzero :: ArrowMonad a a0 #

mplus :: ArrowMonad a a0 -> ArrowMonad a a0 -> ArrowMonad a a0 #

class Arrow a => ArrowLoop (a :: TYPE LiftedRep -> TYPE LiftedRep -> Type) where #

The loop operator expresses computations in which an output value is fed back as input, although the computation occurs only once. It underlies the rec value recursion construct in arrow notation. loop should satisfy the following laws:

extension
loop (arr f) = arr (\ b -> fst (fix (\ (c,d) -> f (b,d))))
left tightening
loop (first h >>> f) = h >>> loop f
right tightening
loop (f >>> first h) = loop f >>> h
sliding
loop (f >>> arr (id *** k)) = loop (arr (id *** k) >>> f)
vanishing
loop (loop f) = loop (arr unassoc >>> f >>> arr assoc)
superposing
second (loop f) = loop (arr assoc >>> second f >>> arr unassoc)

where

assoc ((a,b),c) = (a,(b,c))
unassoc (a,(b,c)) = ((a,b),c)

Methods

loop :: a (b, d) (c, d) -> a b c #

Instances

Instances details
MonadFix m => ArrowLoop (Kleisli m)

Beware that for many monads (those for which the >>= operation is strict) this instance will not satisfy the right-tightening law required by the ArrowLoop class.

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

loop :: Kleisli m (b, d) (c, d) -> Kleisli m b c #

ArrowLoop (->)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

loop :: ((b, d) -> (c, d)) -> b -> c #

(ArrowLoop p, ArrowLoop q) => ArrowLoop (Product p q) 
Instance details

Defined in Data.Bifunctor.Product

Methods

loop :: Product p q (b, d) (c, d) -> Product p q b c #

(Applicative f, ArrowLoop p) => ArrowLoop (Tannen f p) 
Instance details

Defined in Data.Bifunctor.Tannen

Methods

loop :: Tannen f p (b, d) (c, d) -> Tannen f p b c #

class Arrow a => ArrowChoice (a :: TYPE LiftedRep -> TYPE LiftedRep -> Type) where #

Choice, for arrows that support it. This class underlies the if and case constructs in arrow notation.

Instances should satisfy the following laws:

where

assocsum (Left (Left x)) = Left x
assocsum (Left (Right y)) = Right (Left y)
assocsum (Right z) = Right (Right z)

The other combinators have sensible default definitions, which may be overridden for efficiency.

Minimal complete definition

(left | (+++))

Methods

left :: a b c -> a (Either b d) (Either c d) #

Feed marked inputs through the argument arrow, passing the rest through unchanged to the output.

right :: a b c -> a (Either d b) (Either d c) #

A mirror image of left.

The default definition may be overridden with a more efficient version if desired.

(+++) :: a b c -> a b' c' -> a (Either b b') (Either c c') infixr 2 #

Split the input between the two argument arrows, retagging and merging their outputs. Note that this is in general not a functor.

The default definition may be overridden with a more efficient version if desired.

(|||) :: a b d -> a c d -> a (Either b c) d infixr 2 #

Fanin: Split the input between the two argument arrows and merge their outputs.

The default definition may be overridden with a more efficient version if desired.

Instances

Instances details
Monad m => ArrowChoice (Kleisli m)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

left :: Kleisli m b c -> Kleisli m (Either b d) (Either c d) #

right :: Kleisli m b c -> Kleisli m (Either d b) (Either d c) #

(+++) :: Kleisli m b c -> Kleisli m b' c' -> Kleisli m (Either b b') (Either c c') #

(|||) :: Kleisli m b d -> Kleisli m c d -> Kleisli m (Either b c) d #

ArrowChoice (->)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

left :: (b -> c) -> Either b d -> Either c d #

right :: (b -> c) -> Either d b -> Either d c #

(+++) :: (b -> c) -> (b' -> c') -> Either b b' -> Either c c' #

(|||) :: (b -> d) -> (c -> d) -> Either b c -> d #

(ArrowChoice p, ArrowChoice q) => ArrowChoice (Product p q) 
Instance details

Defined in Data.Bifunctor.Product

Methods

left :: Product p q b c -> Product p q (Either b d) (Either c d) #

right :: Product p q b c -> Product p q (Either d b) (Either d c) #

(+++) :: Product p q b c -> Product p q b' c' -> Product p q (Either b b') (Either c c') #

(|||) :: Product p q b d -> Product p q c d -> Product p q (Either b c) d #

(Applicative f, ArrowChoice p) => ArrowChoice (Tannen f p) 
Instance details

Defined in Data.Bifunctor.Tannen

Methods

left :: Tannen f p b c -> Tannen f p (Either b d) (Either c d) #

right :: Tannen f p b c -> Tannen f p (Either d b) (Either d c) #

(+++) :: Tannen f p b c -> Tannen f p b' c' -> Tannen f p (Either b b') (Either c c') #

(|||) :: Tannen f p b d -> Tannen f p c d -> Tannen f p (Either b c) d #

class Arrow a => ArrowApply (a :: TYPE LiftedRep -> TYPE LiftedRep -> Type) where #

Some arrows allow application of arrow inputs to other inputs. Instances should satisfy the following laws:

Such arrows are equivalent to monads (see ArrowMonad).

Methods

app :: a (a b c, b) c #

Instances

Instances details
Monad m => ArrowApply (Kleisli m)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

app :: Kleisli m (Kleisli m b c, b) c #

ArrowApply (->)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

app :: (b -> c, b) -> c #

class Category a => Arrow (a :: TYPE LiftedRep -> TYPE LiftedRep -> Type) where #

The basic arrow class.

Instances should satisfy the following laws:

where

assoc ((a,b),c) = (a,(b,c))

The other combinators have sensible default definitions, which may be overridden for efficiency.

Minimal complete definition

arr, (first | (***))

Methods

arr :: (b -> c) -> a b c #

Lift a function to an arrow.

first :: a b c -> a (b, d) (c, d) #

Send the first component of the input through the argument arrow, and copy the rest unchanged to the output.

second :: a b c -> a (d, b) (d, c) #

A mirror image of first.

The default definition may be overridden with a more efficient version if desired.

(***) :: a b c -> a b' c' -> a (b, b') (c, c') infixr 3 #

Split the input between the two argument arrows and combine their output. Note that this is in general not a functor.

The default definition may be overridden with a more efficient version if desired.

(&&&) :: a b c -> a b c' -> a b (c, c') infixr 3 #

Fanout: send the input to both argument arrows and combine their output.

The default definition may be overridden with a more efficient version if desired.

Instances

Instances details
Monad m => Arrow (Kleisli m)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

arr :: (b -> c) -> Kleisli m b c #

first :: Kleisli m b c -> Kleisli m (b, d) (c, d) #

second :: Kleisli m b c -> Kleisli m (d, b) (d, c) #

(***) :: Kleisli m b c -> Kleisli m b' c' -> Kleisli m (b, b') (c, c') #

(&&&) :: Kleisli m b c -> Kleisli m b c' -> Kleisli m b (c, c') #

Arrow (->)

Since: base-2.1

Instance details

Defined in Control.Arrow

Methods

arr :: (b -> c) -> b -> c #

first :: (b -> c) -> (b, d) -> (c, d) #

second :: (b -> c) -> (d, b) -> (d, c) #

(***) :: (b -> c) -> (b' -> c') -> (b, b') -> (c, c') #

(&&&) :: (b -> c) -> (b -> c') -> b -> (c, c') #

(Arrow p, Arrow q) => Arrow (Product p q) 
Instance details

Defined in Data.Bifunctor.Product

Methods

arr :: (b -> c) -> Product p q b c #

first :: Product p q b c -> Product p q (b, d) (c, d) #

second :: Product p q b c -> Product p q (d, b) (d, c) #

(***) :: Product p q b c -> Product p q b' c' -> Product p q (b, b') (c, c') #

(&&&) :: Product p q b c -> Product p q b c' -> Product p q b (c, c') #

(Applicative f, Arrow p) => Arrow (Tannen f p) 
Instance details

Defined in Data.Bifunctor.Tannen

Methods

arr :: (b -> c) -> Tannen f p b c #

first :: Tannen f p b c -> Tannen f p (b, d) (c, d) #

second :: Tannen f p b c -> Tannen f p (d, b) (d, c) #

(***) :: Tannen f p b c -> Tannen f p b' c' -> Tannen f p (b, b') (c, c') #

(&&&) :: Tannen f p b c -> Tannen f p b c' -> Tannen f p b (c, c') #

returnA :: Arrow a => a b b #

The identity arrow, which plays the role of return in arrow notation.

leftApp :: ArrowApply a => a b c -> a (Either b d) (Either c d) #

Any instance of ArrowApply can be made into an instance of ArrowChoice by defining left = leftApp.

(^>>) :: Arrow a => (b -> c) -> a c d -> a b d infixr 1 #

Precomposition with a pure function.

(^<<) :: Arrow a => (c -> d) -> a b c -> a b d infixr 1 #

Postcomposition with a pure function (right-to-left variant).

(>>^) :: Arrow a => a b c -> (c -> d) -> a b d infixr 1 #

Postcomposition with a pure function.

(<<^) :: Arrow a => a c d -> (b -> c) -> a b d infixr 1 #

Precomposition with a pure function (right-to-left variant).

(>>>) :: forall {k} cat (a :: k) (b :: k) (c :: k). Category cat => cat a b -> cat b c -> cat a c infixr 1 #

Left-to-right composition

(<<<) :: forall {k} cat (b :: k) (c :: k) (a :: k). Category cat => cat b c -> cat a b -> cat a c infixr 1 #

Right-to-left composition

pauseOn :: Show a => (a -> Bool) -> String -> MSF IO a a #

Outputs every input sample, with a given message prefix, when a condition is met, and waits for some input / enter to continue.

traceWhen :: (Monad m, Show a) => (a -> Bool) -> (String -> m ()) -> String -> MSF m a a #

Outputs every input sample, with a given message prefix, using an auxiliary printing function, when a condition is met.

traceWith :: (Monad m, Show a) => (String -> m ()) -> String -> MSF m a a #

Outputs every input sample, with a given message prefix, using an auxiliary printing function.

trace :: Show a => String -> MSF IO a a #

Outputs every input sample, with a given message prefix.

repeatedly :: forall (m :: Type -> Type) a. Monad m => (a -> a) -> a -> MSF m () a #

Generate outputs using a step-wise generation function and an initial value. Version of unfold in which the output and the new accumulator are the same. Should be equal to f a -> unfold (f >>> dup) a.

unfold :: forall (m :: Type -> Type) a b. Monad m => (a -> (b, a)) -> a -> MSF m () b #

Generate outputs using a step-wise generation function and an initial value.

mealy :: forall (m :: Type -> Type) a s b. Monad m => (a -> s -> (b, s)) -> s -> MSF m a b #

Applies a transfer function to the input and an accumulator, returning the updated accumulator and output.

accumulateWith :: forall (m :: Type -> Type) a s. Monad m => (a -> s -> s) -> s -> MSF m a s #

Applies a function to the input and an accumulator, outputting the updated accumulator. Equal to f s0 -> feedback s0 $ arr (uncurry f >>> dup).

mappendFrom :: forall n (m :: Type -> Type). (Monoid n, Monad m) => n -> MSF m n n #

Accumulate the inputs, starting from an initial monoid value.

mappendS :: forall n (m :: Type -> Type). (Monoid n, Monad m) => MSF m n n #

Accumulate the inputs, starting from mempty.

sumFrom :: forall v s (m :: Type -> Type). (VectorSpace v s, Monad m) => v -> MSF m v v #

Sums the inputs, starting from an initial vector.

sumS :: forall v s (m :: Type -> Type). (VectorSpace v s, Monad m) => MSF m v v #

Sums the inputs, starting from zero.

count :: forall n (m :: Type -> Type) a. (Num n, Monad m) => MSF m a n #

Count the number of simulation steps. Produces 1, 2, 3,...

fifo :: forall (m :: Type -> Type) a. Monad m => MSF m [a] (Maybe a) #

Buffers and returns the elements in FIFO order, returning Nothing whenever the buffer is empty.

next :: forall (m :: Type -> Type) b a. Monad m => b -> MSF m a b -> MSF m a b #

Preprends a fixed output to an MSF, shifting the output.

iPost :: forall (m :: Type -> Type) b a. Monad m => b -> MSF m a b -> MSF m a b #

Preprends a fixed output to an MSF. The first input is completely ignored.

iPre #

Arguments

:: forall (m :: Type -> Type) a. Monad m 
=> a

First output

-> MSF m a a 

Delay a signal by one sample.

withSideEffect_ :: Monad m => m b -> MSF m a a #

Produces an additional side effect and passes the input unchanged.

withSideEffect :: Monad m => (a -> m b) -> MSF m a a #

Applies a function to produce an additional side effect and passes the input unchanged.

mapMaybeS :: forall (m :: Type -> Type) a b. Monad m => MSF m a b -> MSF m (Maybe a) (Maybe b) #

Apply an MSF to every input. Freezes temporarily if the input is Nothing, and continues as soon as a Just is received.

type MStream (m :: Type -> Type) a = MSF m () a #

A stream is an MSF that produces outputs, while ignoring the input. It can obtain the values from a monadic context.

type MSink (m :: Type -> Type) a = MSF m a () #

A sink is an MSF that consumes inputs, while producing no output. It can consume the values with side effects.

morphS :: (Monad m2, Monad m1) => (forall c. m1 c -> m2 c) -> MSF m1 a b -> MSF m2 a b #

Apply trans-monadic actions (in an arbitrary way).

This is just a convenience function when you have a function to move across monads, because the signature of morphGS is a bit complex.

liftTransS :: forall (t :: (Type -> Type) -> Type -> Type) (m :: Type -> Type) a b. (MonadTrans t, Monad m, Monad (t m)) => MSF m a b -> MSF (t m) a b #

Lift inner monadic actions in monad stacks.

liftBaseS :: forall (m2 :: Type -> Type) (m1 :: Type -> Type) a b. (Monad m2, MonadBase m1 m2) => MSF m1 a b -> MSF m2 a b #

Lift innermost monadic actions in monad stack (generalisation of liftIO).

liftBaseM :: forall (m2 :: Type -> Type) m1 a b. (Monad m2, MonadBase m1 m2) => (a -> m1 b) -> MSF m2 a b #

Monadic lifting from one monad into another

arrM :: Monad m => (a -> m b) -> MSF m a b #

Apply a monadic transformation to every element of the input stream.

Generalisation of arr from Arrow to monadic functions.

constM :: Monad m => m b -> MSF m a b #

Lifts a monadic computation into a Stream.

reactimate :: Monad m => MSF m () () -> m () #

Run an MSF indefinitely passing a unit-carrying input stream.

embed :: Monad m => MSF m a b -> [a] -> m [b] #

Apply a monadic stream function to a list.

Because the result is in a monad, it may be necessary to traverse the whole list to evaluate the value in the results to WHNF. For example, if the monad is the maybe monad, this may not produce anything if the MSF produces Nothing at any point, so the output stream cannot consumed progressively.

To explore the output progressively, use arrM and (>>>)', together with some action that consumes/actuates on the output.

This is called runSF in Liu, Cheng, Hudak, "Causal Commutative Arrows and Their Optimization"

feedback :: forall (m :: Type -> Type) c a b. Monad m => c -> MSF m (a, c) (b, c) -> MSF m a b #

Well-formed looped connection of an output component as a future input.

morphGS #

Arguments

:: Monad m2 
=> (forall c. (a1 -> m1 (b1, c)) -> a2 -> m2 (b2, c))

The natural transformation. mi, ai and bi for i = 1, 2 can be chosen freely, but c must be universally quantified

-> MSF m1 a1 b1 
-> MSF m2 a2 b2 

Generic lifting of a morphism to the level of MSFs.

Natural transformation to the level of MSFs.

Mathematical background: The type a -> m (b, c) is a functor in c, and MSF m a b is its greatest fixpoint, i.e. it is isomorphic to the type a -> m (b, MSF m a b), by definition. The types m, a and b are parameters of the functor. Taking a fixpoint is functorial itself, meaning that a morphism (a natural transformation) of two such functors gives a morphism (an ordinary function) of their fixpoints.

This is in a sense the most general "abstract" lifting function, i.e. the most general one that only changes input, output and side effect types, and doesn't influence control flow. Other handling functions like exception handling or ListT broadcasting necessarily change control flow.

data MSF (m :: Type -> Type) a b #

Stepwise, side-effectful MSFs without implicit knowledge of time.

MSFs should be applied to streams or executed indefinitely or until they terminate. See reactimate and reactimateB for details. In general, calling the value constructor MSF or the function unMSF is discouraged.

Instances

Instances details
Monad m => Category (MSF m :: Type -> Type -> Type)

Instance definition for Category. Defines id and ..

Instance details

Defined in Data.MonadicStreamFunction.InternalCore

Methods

id :: forall (a :: k). MSF m a a #

(.) :: forall (b :: k) (c :: k) (a :: k). MSF m b c -> MSF m a b -> MSF m a c #