Events and behaviors are the core foundation of FRP in Reactive-banana. Behaviors can be composed via the Applicative interface, but numerous other ways are also provided by the Reactive-banana API. Some primitives are provided:
never :: Event a unionWith :: (a -> a -> a) -> Event a -> Event a -> Event a filterE :: (a -> Bool) -> Event a -> Event a apply :: Behavior (a -> b) -> Event a -> Event b
It's apparent from the types what these functions do. unionWith combines two events using the first argument to decide the result in case of simultaneous emits. filterE suppresses events that don't match a predicate. apply applies a time-varying function to events. Often apply is encountered in its infix form, (<@>).
A special case of apply is replacing events with time-varying values. The (<@) combinator can be used in this case. For example, to turn every event from etick into a random value sampled from behavior...