Safe Haskell	Safe
Language	Haskell2010

Control.Concurrent.EQueue.STMEQueue

Description

This module provides an EQueue implimentation that uses STM to wait on the first available event among a set of possible events. When Waited on it can provide up to one event from every available event source when it provides one event, allowing coalescing.

Synopsis

data STMEQueue a = STMEQueue {
- _eqActiveSources :: TVar (Map Unique (STM (Maybe a)))
}
register :: MonadIO m => STMEQueue a -> STM (Maybe a) -> m (IO ())
newSTMEQueue :: MonadIO m => m (STMEQueue a)
data STMEQueueWait
- = ReturnImmediate
- | RequireEvent

Documentation

data STMEQueue a Source #

A basic example implimentation of an EQueue using STM. This implimentation must look at every registered event source leading to inefficiency in systems with a very large number of sources. For most systems it should be a sufficient implimentation though.

Constructors

STMEQueue
Fields _eqActiveSources :: TVar (Map Unique (STM (Maybe a)))

Instances

EQueueW STMEQueue Source #
Instance details Defined in Control.Concurrent.EQueue.STMEQueue Associated Types type WaitPolicy STMEQueue :: Type Source # Methods waitEQ :: MonadIO m => STMEQueue a -> WaitPolicy STMEQueue -> m [a] Source #
EQueue STMEQueue Source #
Instance details Defined in Control.Concurrent.EQueue.STMEQueue Methods registerSemi :: (MonadIO m, Semigroup b) => STMEQueue a -> (b -> a) -> m (b -> IO (), IO ()) Source # registerQueued :: MonadIO m => STMEQueue a -> m (a -> IO (), IO ()) Source #
type WaitPolicy STMEQueue Source #
Instance details Defined in Control.Concurrent.EQueue.STMEQueue type WaitPolicy STMEQueue = STMEQueueWait

register :: MonadIO m => STMEQueue a -> STM (Maybe a) -> m (IO ()) Source #

Passed an STM dequeueing the current value of this signal. Returns an action to unregister said.

newSTMEQueue :: MonadIO m => m (STMEQueue a) Source #

Create a new STMEQueue which initally has no event sources registered.

data STMEQueueWait Source #

The policy for waiting on an STMEQueue.

Constructors

ReturnImmediate	Immediately return, even if no events are available.
RequireEvent	Wait for at least one event to be available before returning.

Instances

Eq STMEQueueWait Source #
Instance details Defined in Control.Concurrent.EQueue.STMEQueue Methods (==) :: STMEQueueWait -> STMEQueueWait -> Bool # (/=) :: STMEQueueWait -> STMEQueueWait -> Bool #