Module

FRP.Behavior

Package: purescript-behaviors
Repository: paf31/purescript-behaviors

#Behavior Source

newtype Behavior a

A Behavior acts like a continuous function of time.

We can construct a sample a Behavior from some Event, combine Behaviors using Applicative, and sample a final Behavior on some other Event.

Instances

Functor Behavior
Apply Behavior
Applicative Behavior
(Semigroup a) => Semigroup (Behavior a)
(Monoid a) => Monoid (Behavior a)

#behavior Source

behavior :: forall a. (forall b. Event (a -> b) -> Event b) -> Behavior a

Construct a Behavior from its sampling function.

#step Source

step :: forall a. a -> Event a -> Behavior a

Create a Behavior which is updated when an Event fires, by providing an initial value.

#unfold Source

unfold :: forall b a. (a -> b -> b) -> Event a -> b -> Behavior b

Create a Behavior which is updated when an Event fires, by providing an initial value and a function to combine the current value with a new event to create a new value.

#sampleBy Source

sampleBy :: forall c b a. (a -> b -> c) -> Behavior a -> Event b -> Event c

Sample a Behavior on some Event by providing a combining function.

#sample_ Source

sample_ :: forall b a. Behavior a -> Event b -> Event a

Sample a Behavior on some Event, discarding the event's values.

#integral Source

integral :: forall t a. Field t => Semiring a => (((a -> t) -> t) -> a) -> a -> Behavior t -> Behavior a -> Behavior a

Integrate with respect to some measure of time.

This function approximates the integral using the trapezium rule at the implicit sampling interval.

The Semiring a should be a vector field over the field t. To represent this, the user should provide a grate which lifts a multiplication function on t to a function on a. Simple examples where t ~ a can use the integral' function instead.

#integral' Source

integral' :: forall t. Field t => t -> Behavior t -> Behavior t -> Behavior t

Integrate with respect to some measure of time.

This function is a simpler version of integral where the function being integrated takes values in the same field used to represent time.

#derivative Source

derivative :: forall t a. Field t => Ring a => (((a -> t) -> t) -> a) -> Behavior t -> Behavior a -> Behavior a

Differentiate with respect to some measure of time.

This function approximates the derivative using a quotient of differences at the implicit sampling interval.

The Semiring a should be a vector field over the field t. To represent this, the user should provide a grate which lifts a division function on t to a function on a. Simple examples where t ~ a can use the derivative' function.

#derivative' Source

derivative' :: forall t. Field t => Behavior t -> Behavior t -> Behavior t