Control.Arrow.Machine.Utils

AFRP-like utilities

delay :: (ArrowApply a, Occasional b) => ProcessA a b b

hold :: ArrowApply a => b -> ProcessA a (Event b) b

accum :: ArrowApply a => b -> ProcessA a (Event (b -> b)) b

edge :: (ArrowApply a, Eq b) => ProcessA a b (Event b)

passRecent :: (ArrowApply a, Occasional o) => ProcessA a (AS e) (Event b) -> ProcessA a (e, AS b) o -> ProcessA a (AS e) o infixr 9

Deprecated: Use hold instead

withRecent :: (ArrowApply a, Occasional o) => ProcessA a (e, AS b) o -> ProcessA a (e, AS (Event b)) o

Deprecated: Use hold instead

feedback1 :: (ArrowApply a, Occasional d) => ProcessA a (e, AS d) (c, d) -> ProcessA a (AS e) c

Deprecated: Use Pump instead

Event version of loop (member of ArrowLoop). Yielding an event to feedback output always creates a new process cycle. So be careful to make an infinite loop.

feedback :: (ArrowApply a, Occasional d) => ProcessA a (e, AS d) b -> ProcessA a (e, AS b) (c, d) -> ProcessA a (AS e) c infixr 9

Deprecated: Use Pump instead

Artificially split into two arrow to use binary operator notation rather than banana brackets.

Switches

Switches inspired by Yampa library. Signature is almost same, but collection requirement is not only Functor, but Traversable. This is because of side effects.

switch :: ArrowApply a => ProcessA a b (c, Event t) -> (t -> ProcessA a b c) -> ProcessA a b c

dSwitch :: ArrowApply a => ProcessA a b (c, Event t) -> (t -> ProcessA a b c) -> ProcessA a b c

rSwitch :: ArrowApply a => ProcessA a b c -> ProcessA a (b, Event (ProcessA a b c)) c

drSwitch :: ArrowApply a => ProcessA a b c -> ProcessA a (b, Event (ProcessA a b c)) c

kSwitch :: ArrowApply a => ProcessA a b c -> ProcessA a (b, c) (Event t) -> (ProcessA a b c -> t -> ProcessA a b c) -> ProcessA a b c

dkSwitch :: ArrowApply a => ProcessA a b c -> ProcessA a (b, c) (Event t) -> (ProcessA a b c -> t -> ProcessA a b c) -> ProcessA a b c

pSwitch :: (ArrowApply a, Traversable col) => (forall sf. b -> col sf -> col (ext, sf)) -> col (ProcessA a ext c) -> ProcessA a (b, col c) (Event mng) -> (col (ProcessA a ext c) -> mng -> ProcessA a b (col c)) -> ProcessA a b (col c)

pSwitchB :: (ArrowApply a, Traversable col) => col (ProcessA a b c) -> ProcessA a (b, col c) (Event mng) -> (col (ProcessA a b c) -> mng -> ProcessA a b (col c)) -> ProcessA a b (col c)

rpSwitch :: (ArrowApply a, Traversable col) => (forall sf. b -> col sf -> col (ext, sf)) -> col (ProcessA a ext c) -> ProcessA a (b, Event (col (ProcessA a ext c) -> col (ProcessA a ext c))) (col c)

rpSwitchB :: (ArrowApply a, Traversable col) => col (ProcessA a b c) -> ProcessA a (b, Event (col (ProcessA a b c) -> col (ProcessA a b c))) (col c)

State arrow

peekState :: (ArrowApply a, ArrowState s a) => ProcessA a e s

encloseState :: (ArrowApply a, ArrowAddState s a a') => ProcessA a b c -> s -> ProcessA a' b c

Other utility arrows

tee :: ArrowApply a => ProcessA a (Event b1, Event b2) (Event (Either b1 b2))

Make two event streams into one. Actually gather is more general and convenient; ... <- tee -< (e1, e2) is equivalent to ... gather -< [Left <$ e1, Right $ e2]

gather :: (ArrowApply a, Foldable f) => ProcessA a (f (Event b)) (Event b)

Make multiple event channels into one. If simultaneous events are given, lefter one is emitted earlier.

sample :: ArrowApply a => ProcessA a (Event b1, Event b2) [b1]

source :: (ArrowApply a, Foldable f) => f c -> ProcessA a (Event b) (Event c)

Provides a source event stream. A dummy input event stream is needed. run af [...] is equivalent to run (source [...] >>> af) (repeat ())

fork :: (ArrowApply a, Foldable f) => ProcessA a (Event (f b)) (Event b)

Given an array-valued event and emit it's values as inidvidual events.

filter :: ArrowApply a => a o Bool -> ProcessA a (Event o) (Event o)

echo :: ArrowApply a => ProcessA a (Event b) (Event b)

anytime :: ArrowApply a => a b c -> ProcessA a (Event b) (Event c)

Executes an action once per an input event is provided.

par :: (ArrowApply a, Traversable col) => (forall sf. b -> col sf -> col (ext, sf)) -> col (ProcessA a ext c) -> ProcessA a b (col c)

parB :: (ArrowApply a, Traversable col) => col (ProcessA a b c) -> ProcessA a b (col c)

onEnd :: (ArrowApply a, Occasional b) => ProcessA a b (Event ())

cycleDelay :: ArrowApply a => ProcessA a b b

Observe a previous value of a signal. Tipically used with rec statement.