Signal

data Signal :: Type -> Type

Instances

• Functor Signal
• Apply Signal
• Applicative Signal
• Semigroup (Signal a)
• (Monoid a) => Monoid (Signal a)

constant :: forall a. a -> Signal a

Creates a signal with a constant value.

merge :: forall a. (Signal a) -> (Signal a) -> (Signal a)

Merge two signals, returning a new signal which will yield a value whenever either of the input signals yield. Its initial value will be that of the first signal.

mergeMany :: forall a f. Functor f => Foldable f => f (Signal a) -> Maybe (Signal a)

Merge all signals inside a Foldable, returning a Maybe which will either contain the resulting signal, or Nothing if the Foldable was empty.

foldp :: forall b a. (a -> b -> b) -> b -> (Signal a) -> (Signal b)

Creates a past dependent signal. The function argument takes the value of the input signal, and the previous value of the output signal, to produce the new value of the output signal.

sampleOn :: forall b a. (Signal a) -> (Signal b) -> (Signal b)

Creates a signal which yields the current value of the second signal every time the first signal yields.

dropRepeats :: forall a. Eq a => Signal a -> Signal a

Create a signal which only yields values which aren't equal to the previous value of the input signal.

dropRepeats' :: forall a. (Signal a) -> (Signal a)

Create a signal which only yields values which aren't equal to the previous value of the input signal, using JavaScript's !== operator to determine disequality.

runSignal :: Signal (Effect Unit) -> Effect Unit

Given a signal of effects with no return value, run each effect as it comes in.

unwrap :: forall a. Signal (Effect a) -> Effect (Signal a)

Takes a signal of effects of a, and produces an effect which returns a signal which will take each effect produced by the input signal, run it, and yield its returned value.

get :: forall a. Signal a -> Effect a

Gets the current value of the signal.

filter :: forall a. (a -> Boolean) -> a -> (Signal a) -> (Signal a)

Takes a signal and filters out yielded values for which the provided predicate function returns false.

filterMap :: forall b a. (a -> Maybe b) -> b -> Signal a -> Signal b

Map a signal over a function which returns a Maybe, yielding only the values inside Justs, dropping the Nothings.

flatten :: forall f a. Functor f => Foldable f => Signal (f a) -> a -> Signal a

Turns a signal of collections of items into a signal of each item inside each collection, in order.

flattenArray :: forall a. Signal (Array a) -> a -> Signal a

Turns a signal of arrays of items into a signal of each item inside each array, in order.

Like flatten, but faster.

Operator alias for Signal.squigglyMap (left-associative / precedence 4)

Operator alias for Signal.flippedMap (left-associative / precedence 4)

Operator alias for Signal.squigglyApply (left-associative / precedence 4)

squigglyMap :: forall b a f. Functor f => (a -> b) -> f a -> f b

squigglyApply :: forall b a f. Apply f => f (a -> b) -> f a -> f b

flippedMap :: forall b a f. Functor f => f a -> (a -> b) -> f b

map2 :: forall c b a. (a -> b -> c) -> Signal a -> Signal b -> Signal c

map3 :: forall d c b a. (a -> b -> c -> d) -> Signal a -> Signal b -> Signal c -> Signal d

map4 :: forall e d c b a. (a -> b -> c -> d -> e) -> Signal a -> Signal b -> Signal c -> Signal d -> Signal e

map5 :: forall f e d c b a. (a -> b -> c -> d -> e -> f) -> Signal a -> Signal b -> Signal c -> Signal d -> Signal e -> Signal f