Safe Haskell	Safe
Language	Haskell2010

Control.Monad.Schedule

Description

This module supplies a general purpose monad transformer that adds a syntactical "delay", or "waiting" side effect.

This allows for universal and deterministic scheduling of clocks that implement their waiting actions in ScheduleT. See Trans for more details.

Synopsis

data Wait diff a = Wait diff a
type ScheduleT diff = FreeT (Wait diff)
wait :: Monad m => diff -> ScheduleT diff m ()
runScheduleT :: Monad m => (diff -> m ()) -> ScheduleT diff m a -> m a
runScheduleIO :: (MonadIO m, Integral n) => ScheduleT n m a -> m a
race :: (Ord diff, Num diff, Monad m) => ScheduleT diff m a -> ScheduleT diff m b -> ScheduleT diff m (Either (a, ScheduleT diff m b) (ScheduleT diff m a, b))
async :: (Ord diff, Num diff, Monad m) => ScheduleT diff m a -> ScheduleT diff m b -> ScheduleT diff m (a, b)

Documentation

data Wait diff a Source #

A functor implementing a syntactical "waiting" action.

diff represents the duration to wait.
a is the encapsulated value.

Constructors

Wait diff a

Instances

Functor (Wait diff) Source #
Instance details Defined in Control.Monad.Schedule Methods fmap :: (a -> b) -> Wait diff a -> Wait diff b # (<$) :: a -> Wait diff b -> Wait diff a #
(Monad m, NonemptyNatList v) => Clock (ScheduleT Integer m) (Periodic v) Source #
Instance details Defined in FRP.Rhine.Clock.Periodic Associated Types type Time (Periodic v) :: * Source # type Tag (Periodic v) :: * Source # Methods initClock :: Periodic v -> RunningClockInit (ScheduleT Integer m) (Time (Periodic v)) (Tag (Periodic v)) Source #

type ScheduleT diff = FreeT (Wait diff) Source #

Values in ScheduleT diff m are delayed computations with side effects in m. Delays can occur between any two side effects, with lengths specified by a diff value. These delays don't have any semantics, it can be given to them with runScheduleT.

wait :: Monad m => diff -> ScheduleT diff m () Source #

The side effect that waits for a specified amount.

runScheduleT :: Monad m => (diff -> m ()) -> ScheduleT diff m a -> m a Source #

Supply a semantic meaning to Wait. For every occurrence of Wait diff in the ScheduleT diff m a value, a waiting action is executed, depending on diff.

runScheduleIO :: (MonadIO m, Integral n) => ScheduleT n m a -> m a Source #

Run a ScheduleT value in a MonadIO, interpreting the times as milliseconds.

race :: (Ord diff, Num diff, Monad m) => ScheduleT diff m a -> ScheduleT diff m b -> ScheduleT diff m (Either (a, ScheduleT diff m b) (ScheduleT diff m a, b)) Source #

Runs two values in ScheduleT concurrently and returns the first one that yields a value (defaulting to the first argument), and a continuation for the other value.

async :: (Ord diff, Num diff, Monad m) => ScheduleT diff m a -> ScheduleT diff m b -> ScheduleT diff m (a, b) Source #

Runs both schedules concurrently and returns their results at the end.