Control.Monad.Trans.Task

Task monad transformer

newtype TaskT e m a

Task monad transformer.

Constructors

TaskT

Fields

• runTaskT :: ContT (Trace m e) m a

Instances

MonadState s m => MonadState s (TaskT e m)

Methods

get :: TaskT e m s

put :: s -> TaskT e m ()

state :: (s -> (a, s)) -> TaskT e m a

MonadReader s m => MonadReader s (TaskT e m)

Methods

ask :: TaskT e m s

local :: (s -> s) -> TaskT e m a -> TaskT e m a

reader :: (s -> a) -> TaskT e m a

Monad m => MonadTask e (TaskT e m)

Methods

yield :: TaskT e m ()

fork :: TaskT e m a -> TaskT e m ()

watch :: (e -> Maybe a) -> TaskT e m a

signal :: e -> TaskT e m ()

exit :: TaskT e m ()

MonadTrans (TaskT e)

Methods

lift :: Monad m => m a -> TaskT e m a

Monad m => Monad (TaskT e m)

Methods

(>>=) :: TaskT e m a -> (a -> TaskT e m b) -> TaskT e m b

(>>) :: TaskT e m a -> TaskT e m b -> TaskT e m b

return :: a -> TaskT e m a

fail :: String -> TaskT e m a

Functor (TaskT e m)

Methods

fmap :: (a -> b) -> TaskT e m a -> TaskT e m b

(<$) :: a -> TaskT e m b -> TaskT e m a

Applicative (TaskT e m)

Methods

pure :: a -> TaskT e m a

(<*>) :: TaskT e m (a -> b) -> TaskT e m a -> TaskT e m b

liftA2 :: (a -> b -> c) -> TaskT e m a -> TaskT e m b -> TaskT e m c

(*>) :: TaskT e m a -> TaskT e m b -> TaskT e m b

(<*) :: TaskT e m a -> TaskT e m b -> TaskT e m a

MonadIO m => MonadIO (TaskT e m)

Methods

liftIO :: IO a -> TaskT e m a

Trace of a base monad

data Trace m e where

A Trace m e represents the control flow of a mult-threaded task monad defined over a base monad m and event type e.

Constructors

EXIT :: Trace m e

RET :: Trace m e

YIELD :: m (Trace m e) -> Trace m e

FORK :: m (Trace m e) -> m (Trace m e) -> Trace m e

WATCH :: (e -> Maybe v) -> (v -> m (Trace m e)) -> Trace m e

SIGNAL :: e -> m (Trace m e) -> Trace m e

runTrace :: Monad m => m (Trace m e) -> m ()

runTrace runs a trace to its completion in the base monad with a simple round-robin scheduler.

Task functions

taskToTrace :: Monad m => TaskT e m a -> m (Trace m e)

tasktoTrace CPS-converts a task monad into a trace in its base monad.

runTask :: Monad m => TaskT e m a -> m ()

runTask runs a task monad until to its completion, i.e., no more active tasks to run, or until it exits.

• runTask = runTrace . taskToTrace