Simulation.Aivika.Internal.Cont

Tested with: GHC 8.0.1

This is an internal implementation module that should never be used directly.

The Cont monad is a variation of the standard Cont monad and F# async workflow, where the result of applying the continuations is the Event computation.

Documentation

data ContCancellation

It defines how the parent and child computations should be cancelled.

Constructors

CancelTogether

Cancel the both computations together.

CancelChildAfterParent

Cancel the child if its parent is cancelled.

CancelParentAfterChild

Cancel the parent if its child is cancelled.

CancelInIsolation

Cancel the computations in isolation.

data ContId

It identifies the Cont computation.

Instances

Eq ContId

Defined in Simulation.Aivika.Internal.Cont

Methods

(==) :: ContId -> ContId -> Bool

(/=) :: ContId -> ContId -> Bool

data ContEvent

The event that occurs within the Cont computation.

Constructors

ContCancellationInitiating

Cancel the computation.

ContPreemptionBeginning

Preempt the computation.

ContPreemptionEnding

Proceed with the computation after if was preempted.

Instances

Eq ContEvent

Defined in Simulation.Aivika.Internal.Cont

Methods

(==) :: ContEvent -> ContEvent -> Bool

(/=) :: ContEvent -> ContEvent -> Bool

Ord ContEvent

Defined in Simulation.Aivika.Internal.Cont

Methods

compare :: ContEvent -> ContEvent -> Ordering

(<) :: ContEvent -> ContEvent -> Bool

(<=) :: ContEvent -> ContEvent -> Bool

(>) :: ContEvent -> ContEvent -> Bool

(>=) :: ContEvent -> ContEvent -> Bool

max :: ContEvent -> ContEvent -> ContEvent

min :: ContEvent -> ContEvent -> ContEvent

Show ContEvent

Defined in Simulation.Aivika.Internal.Cont

Methods

showsPrec :: Int -> ContEvent -> ShowS

show :: ContEvent -> String

showList :: [ContEvent] -> ShowS

newtype Cont a

The Cont type is similar to the standard Cont monad and F# async workflow but only the result of applying the continuations return the Event computation.

Constructors

Cont (ContParams a -> Event ())

Instances

Monad Cont

Defined in Simulation.Aivika.Internal.Cont

Methods

(>>=) :: Cont a -> (a -> Cont b) -> Cont b

(>>) :: Cont a -> Cont b -> Cont b

return :: a -> Cont a

fail :: String -> Cont a

Functor Cont

Defined in Simulation.Aivika.Internal.Cont

Methods

fmap :: (a -> b) -> Cont a -> Cont b

(<$) :: a -> Cont b -> Cont a

Applicative Cont

Defined in Simulation.Aivika.Internal.Cont

Methods

pure :: a -> Cont a

(<*>) :: Cont (a -> b) -> Cont a -> Cont b

liftA2 :: (a -> b -> c) -> Cont a -> Cont b -> Cont c

(*>) :: Cont a -> Cont b -> Cont b

(<*) :: Cont a -> Cont b -> Cont a

MonadIO Cont

Defined in Simulation.Aivika.Internal.Cont

Methods

liftIO :: IO a -> Cont a

MonadThrow Cont

Defined in Simulation.Aivika.Internal.Cont

Methods

throwM :: Exception e => e -> Cont a

MonadCatch Cont

Defined in Simulation.Aivika.Internal.Cont

Methods

catch :: Exception e => Cont a -> (e -> Cont a) -> Cont a

ParameterLift Cont

Defined in Simulation.Aivika.Internal.Cont

Methods

liftParameter :: Parameter a -> Cont a

SimulationLift Cont

Defined in Simulation.Aivika.Internal.Cont

Methods

liftSimulation :: Simulation a -> Cont a

DynamicsLift Cont

Defined in Simulation.Aivika.Internal.Cont

Methods

liftDynamics :: Dynamics a -> Cont a

EventLift Cont

Defined in Simulation.Aivika.Internal.Cont

Methods

liftEvent :: Event a -> Cont a

data ContParams a

The continuation parameters.

data FrozenCont a

Represents a temporarily frozen computation.

newContId :: Simulation ContId

Create a computation identifier.

contSignal :: ContId -> Signal ContEvent

Signal when the computation state changes.

contCancellationInitiated :: ContId -> Event Bool

Whether the cancellation was initiated.

contCancellationInitiate :: ContId -> Event ()

Initiate the cancellation.

contCancellationInitiating :: ContId -> Signal ()

Signal when the cancellation is intiating.

contCancellationActivated :: ContId -> IO Bool

Whether the cancellation was activated.

contCancellationBind :: ContId -> [ContId] -> Event DisposableEvent

If the main computation is cancelled then all the nested ones will be cancelled too.

contCancellationConnect

Arguments

:: ContId

the parent

-> ContCancellation

how to connect

-> ContId

the child

-> Event DisposableEvent

computation of the disposable handler

Connect the parent computation to the child one.

contPreemptionBegun :: ContId -> Event Bool

Whether the computation was preemtped.

contPreemptionBegin :: ContId -> Event ()

Preempt the computation.

contPreemptionBeginning :: ContId -> Signal ()

Signal when the computation is preempted.

contPreemptionEnd :: ContId -> Event ()

Proceed with the computation after it was preempted earlier.

contPreemptionEnding :: ContId -> Signal ()

Signal when the computation is proceeded after it was preempted before.

invokeCont :: ContParams a -> Cont a -> Event ()

Invoke the computation.

runCont

Arguments

:: Cont a

the computation to run

-> (a -> Event ())

the main branch

-> (SomeException -> Event ())

the branch for handing exceptions

-> (() -> Event ())

the branch for cancellation

-> ContId

the computation identifier

-> Bool

whether to support the exception handling from the beginning

-> Event ()

Run the Cont computation with the specified cancelation source and flag indicating whether to catch exceptions from the beginning.

rerunCont :: Cont a -> ContId -> Cont a

Rerun the Cont computation with the specified identifier.

spawnCont :: ContCancellation -> Cont () -> ContId -> Cont ()

Run the Cont computation in parallel but connect the computations.

contParallel

Arguments

:: [(Cont a, ContId)]

the list of: the nested computation, the computation identifier

-> Cont [a]

Execute the specified computations in parallel within the current computation and return their results. The cancellation of any of the nested computations affects the current computation. The exception raised in any of the nested computations is propogated to the current computation as well (if the exception handling is supported).

Here word parallel literally means that the computations are actually executed on a single operating system thread but they are processed simultaneously by the event queue.

contParallel_

Arguments

:: [(Cont a, ContId)]

the list of: the nested computation, the computation identifier

-> Cont ()

A partial case of contParallel when we are not interested in the results but we are interested in the actions to be peformed by the nested computations.

catchCont :: Exception e => Cont a -> (e -> Cont a) -> Cont a

Exception handling within Cont computations.

finallyCont :: Cont a -> Cont b -> Cont a

A computation with finalization part.

throwCont :: Exception e => e -> Cont a

Throw the exception with the further exception handling.

By some reason, an exception raised with help of the standard throw function is not handled properly within Cont computation, altough it will be still handled if it will be wrapped in the IO monad. Therefore, you should use specialised functions like the stated one that use the throw function but within the IO computation, which allows already handling the exception.

resumeCont :: ContParams a -> a -> Event ()

Resume the computation by the specified parameters.

resumeECont :: ContParams a -> SomeException -> Event ()

Resume the exception handling by the specified parameters.

reenterCont :: ContParams a -> a -> Event ()

Reenter the computation parameters when needed.

freezeCont :: ContParams a -> Event (FrozenCont a)

Freeze the computation parameters temporarily.

freezeContReentering :: ContParams a -> a -> Event () -> Event (FrozenCont a)

Freeze the computation parameters specifying what should be done when reentering the computation.

unfreezeCont :: FrozenCont a -> Event (Maybe (ContParams a))

Unfreeze the computation.

substituteCont :: ContParams a -> (a -> Event ()) -> ContParams a

Substitute the continuation.

contCanceled :: ContParams a -> IO Bool

Test whether the computation is canceled.

contAwait :: Signal a -> Cont a

Await the signal.

transferCont :: Cont () -> Cont a

Like the GoTo statement it transfers the direction of computation, but raises an exception when used within catchCont or finallyCont.

traceCont :: String -> Cont a -> Cont a

Show the debug message with the current simulation time.