Simulation.Aivika.Ref

Tested with: GHC 7.10.1

This module defines an updatable reference that depends on the event queue.

Documentation

data Ref a

The Ref type represents a mutable variable similar to the IORef variable but only dependent on the event queue, which allows synchronizing the reference with the model explicitly through the Event monad.

Instances

ResultComputing Ref

refChanged :: Ref a -> Signal a

Return a signal that notifies about every change of the reference state.

refChanged_ :: Ref a -> Signal ()

Return a signal that notifies about every change of the reference state.

newRef :: a -> Simulation (Ref a)

Create a new reference.

readRef :: Ref a -> Event a

Read the value of a reference.

writeRef :: Ref a -> a -> Event ()

Write a new value into the reference.

modifyRef :: Ref a -> (a -> a) -> Event ()

Mutate the contents of the reference.