Copyright  Copyright (C) 20122018 Mitsutoshi Aoe 

License  BSDstyle (see the file LICENSE) 
Maintainer  Mitsutoshi Aoe <maoe@foldr.in> 
Stability  experimental 
Safe Haskell  None 
Language  Haskell98 
This is a wrapped version of Control.Concurrent.Async
with types generalized
from IO
to all monads in either MonadBase
or MonadBaseControl
.
All the functions restore the monadic effects in the forked computation unless specified otherwise.
If your monad stack satisfies
(e.g. the reader monad), consider
using StM
m a ~ aControl.Concurrent.Async.Lifted.Safe
module, which prevents you from
messing up monadic effects.
Synopsis
 data Async a
 async :: MonadBaseControl IO m => m a > m (Async (StM m a))
 asyncBound :: MonadBaseControl IO m => m a > m (Async (StM m a))
 asyncOn :: MonadBaseControl IO m => Int > m a > m (Async (StM m a))
 asyncWithUnmask :: MonadBaseControl IO m => ((forall b. m b > m b) > m a) > m (Async (StM m a))
 asyncOnWithUnmask :: MonadBaseControl IO m => Int > ((forall b. m b > m b) > m a) > m (Async (StM m a))
 withAsync :: MonadBaseControl IO m => m a > (Async (StM m a) > m b) > m b
 withAsyncBound :: MonadBaseControl IO m => m a > (Async (StM m a) > m b) > m b
 withAsyncOn :: MonadBaseControl IO m => Int > m a > (Async (StM m a) > m b) > m b
 withAsyncWithUnmask :: MonadBaseControl IO m => ((forall c. m c > m c) > m a) > (Async (StM m a) > m b) > m b
 withAsyncOnWithUnmask :: MonadBaseControl IO m => Int > ((forall c. m c > m c) > m a) > (Async (StM m a) > m b) > m b
 wait :: MonadBaseControl IO m => Async (StM m a) > m a
 poll :: MonadBaseControl IO m => Async (StM m a) > m (Maybe (Either SomeException a))
 waitCatch :: MonadBaseControl IO m => Async (StM m a) > m (Either SomeException a)
 cancel :: MonadBase IO m => Async a > m ()
 uninterruptibleCancel :: MonadBase IO m => Async a > m ()
 cancelWith :: (MonadBase IO m, Exception e) => Async a > e > m ()
 asyncThreadId :: Async a > ThreadId
 data AsyncCancelled = AsyncCancelled
 waitSTM :: Async a > STM a
 pollSTM :: Async a > STM (Maybe (Either SomeException a))
 waitCatchSTM :: Async a > STM (Either SomeException a)
 waitAny :: MonadBaseControl IO m => [Async (StM m a)] > m (Async (StM m a), a)
 waitAnyCatch :: MonadBaseControl IO m => [Async (StM m a)] > m (Async (StM m a), Either SomeException a)
 waitAnyCancel :: MonadBaseControl IO m => [Async (StM m a)] > m (Async (StM m a), a)
 waitAnyCatchCancel :: MonadBaseControl IO m => [Async (StM m a)] > m (Async (StM m a), Either SomeException a)
 waitEither :: MonadBaseControl IO m => Async (StM m a) > Async (StM m b) > m (Either a b)
 waitEitherCatch :: MonadBaseControl IO m => Async (StM m a) > Async (StM m b) > m (Either (Either SomeException a) (Either SomeException b))
 waitEitherCancel :: MonadBaseControl IO m => Async (StM m a) > Async (StM m b) > m (Either a b)
 waitEitherCatchCancel :: MonadBaseControl IO m => Async (StM m a) > Async (StM m b) > m (Either (Either SomeException a) (Either SomeException b))
 waitEither_ :: MonadBase IO m => Async a > Async b > m ()
 waitBoth :: MonadBaseControl IO m => Async (StM m a) > Async (StM m b) > m (a, b)
 waitAnySTM :: [Async a] > STM (Async a, a)
 waitAnyCatchSTM :: [Async a] > STM (Async a, Either SomeException a)
 waitEitherSTM :: Async a > Async b > STM (Either a b)
 waitEitherCatchSTM :: Async a > Async b > STM (Either (Either SomeException a) (Either SomeException b))
 waitEitherSTM_ :: Async a > Async b > STM ()
 waitBothSTM :: Async a > Async b > STM (a, b)
 link :: MonadBase IO m => Async a > m ()
 link2 :: MonadBase IO m => Async a > Async b > m ()
 data ExceptionInLinkedThread where
 ExceptionInLinkedThread :: forall a. Async a > SomeException > ExceptionInLinkedThread
 race :: MonadBaseControl IO m => m a > m b > m (Either a b)
 race_ :: MonadBaseControl IO m => m a > m b > m ()
 concurrently :: MonadBaseControl IO m => m a > m b > m (a, b)
 concurrently_ :: MonadBaseControl IO m => m a > m b > m ()
 mapConcurrently :: (Traversable t, MonadBaseControl IO m) => (a > m b) > t a > m (t b)
 mapConcurrently_ :: (Foldable t, MonadBaseControl IO m) => (a > m b) > t a > m ()
 forConcurrently :: (Traversable t, MonadBaseControl IO m) => t a > (a > m b) > m (t b)
 forConcurrently_ :: (Foldable t, MonadBaseControl IO m) => t a > (a > m b) > m ()
 replicateConcurrently :: MonadBaseControl IO m => Int > m a > m [a]
 replicateConcurrently_ :: MonadBaseControl IO m => Int > m a > m ()
 newtype Concurrently m a = Concurrently {
 runConcurrently :: m a
 compareAsyncs :: Async a > Async b > Ordering
Asynchronous actions
An asynchronous action spawned by async
or withAsync
.
Asynchronous actions are executed in a separate thread, and
operations are provided for waiting for asynchronous actions to
complete and obtaining their results (see e.g. wait
).
Spawning
asyncBound :: MonadBaseControl IO m => m a > m (Async (StM m a)) #
Generalized version of asyncBound
.
asyncOn :: MonadBaseControl IO m => Int > m a > m (Async (StM m a)) #
Generalized version of asyncOn
.
asyncWithUnmask :: MonadBaseControl IO m => ((forall b. m b > m b) > m a) > m (Async (StM m a)) #
Generalized version of asyncWithUnmask
.
asyncOnWithUnmask :: MonadBaseControl IO m => Int > ((forall b. m b > m b) > m a) > m (Async (StM m a)) #
Generalized version of asyncOnWithUnmask
.
Spawning with automatic
cancel
ation
withAsync :: MonadBaseControl IO m => m a > (Async (StM m a) > m b) > m b #
Generalized version of withAsync
.
withAsyncBound :: MonadBaseControl IO m => m a > (Async (StM m a) > m b) > m b #
Generalized version of withAsyncBound
.
withAsyncOn :: MonadBaseControl IO m => Int > m a > (Async (StM m a) > m b) > m b #
Generalized version of withAsyncOn
.
withAsyncWithUnmask :: MonadBaseControl IO m => ((forall c. m c > m c) > m a) > (Async (StM m a) > m b) > m b #
Generalized version of withAsyncWithUnmask
.
withAsyncOnWithUnmask :: MonadBaseControl IO m => Int > ((forall c. m c > m c) > m a) > (Async (StM m a) > m b) > m b #
Generalized version of withAsyncOnWithUnmask
.
Quering
Async
s
poll :: MonadBaseControl IO m => Async (StM m a) > m (Maybe (Either SomeException a)) #
Generalized version of poll
.
waitCatch :: MonadBaseControl IO m => Async (StM m a) > m (Either SomeException a) #
Generalized version of waitCatch
.
uninterruptibleCancel :: MonadBase IO m => Async a > m () #
Generalized version of uninterruptibleCancel
.
cancelWith :: (MonadBase IO m, Exception e) => Async a > e > m () #
Generalized version of cancelWith
.
data AsyncCancelled #
The exception thrown by cancel
to terminate a thread.
Instances
Eq AsyncCancelled  
Defined in Control.Concurrent.Async (==) :: AsyncCancelled > AsyncCancelled > Bool # (/=) :: AsyncCancelled > AsyncCancelled > Bool #  
Show AsyncCancelled  
Defined in Control.Concurrent.Async showsPrec :: Int > AsyncCancelled > ShowS # show :: AsyncCancelled > String # showList :: [AsyncCancelled] > ShowS #  
Exception AsyncCancelled  
Defined in Control.Concurrent.Async 
STM operations
pollSTM :: Async a > STM (Maybe (Either SomeException a)) #
A version of poll
that can be used inside an STM transaction.
waitCatchSTM :: Async a > STM (Either SomeException a) #
A version of waitCatch
that can be used inside an STM transaction.
Waiting for multiple
Async
s
waitAny :: MonadBaseControl IO m => [Async (StM m a)] > m (Async (StM m a), a) #
Generalized version of waitAny
.
waitAnyCatch :: MonadBaseControl IO m => [Async (StM m a)] > m (Async (StM m a), Either SomeException a) #
Generalized version of waitAnyCatch
.
waitAnyCancel :: MonadBaseControl IO m => [Async (StM m a)] > m (Async (StM m a), a) #
Generalized version of waitAnyCancel
.
waitAnyCatchCancel :: MonadBaseControl IO m => [Async (StM m a)] > m (Async (StM m a), Either SomeException a) #
Generalized version of waitAnyCatchCancel
.
waitEither :: MonadBaseControl IO m => Async (StM m a) > Async (StM m b) > m (Either a b) #
Generalized version of waitEither
.
waitEitherCatch :: MonadBaseControl IO m => Async (StM m a) > Async (StM m b) > m (Either (Either SomeException a) (Either SomeException b)) #
Generalized version of waitEitherCatch
.
waitEitherCancel :: MonadBaseControl IO m => Async (StM m a) > Async (StM m b) > m (Either a b) #
Generalized version of waitEitherCancel
.
waitEitherCatchCancel :: MonadBaseControl IO m => Async (StM m a) > Async (StM m b) > m (Either (Either SomeException a) (Either SomeException b)) #
Generalized version of waitEitherCatchCancel
.
waitEither_ :: MonadBase IO m => Async a > Async b > m () #
Generalized version of waitEither_
.
NOTE: This function discards the monadic effects besides IO in the forked computation.
waitBoth :: MonadBaseControl IO m => Async (StM m a) > Async (StM m b) > m (a, b) #
Generalized version of waitBoth
.
Waiting for multiple
Async
s in STM
waitAnySTM :: [Async a] > STM (Async a, a) #
A version of waitAny
that can be used inside an STM transaction.
Since: async2.1.0
waitAnyCatchSTM :: [Async a] > STM (Async a, Either SomeException a) #
A version of waitAnyCatch
that can be used inside an STM transaction.
Since: async2.1.0
waitEitherSTM :: Async a > Async b > STM (Either a b) #
A version of waitEither
that can be used inside an STM transaction.
Since: async2.1.0
waitEitherCatchSTM :: Async a > Async b > STM (Either (Either SomeException a) (Either SomeException b)) #
A version of waitEitherCatch
that can be used inside an STM transaction.
Since: async2.1.0
waitEitherSTM_ :: Async a > Async b > STM () #
A version of waitEither_
that can be used inside an STM transaction.
Since: async2.1.0
waitBothSTM :: Async a > Async b > STM (a, b) #
A version of waitBoth
that can be used inside an STM transaction.
Since: async2.1.0
Linking
data ExceptionInLinkedThread where #
ExceptionInLinkedThread :: forall a. Async a > SomeException > ExceptionInLinkedThread 
Instances
Show ExceptionInLinkedThread  
Defined in Control.Concurrent.Async showsPrec :: Int > ExceptionInLinkedThread > ShowS # show :: ExceptionInLinkedThread > String # showList :: [ExceptionInLinkedThread] > ShowS #  
Exception ExceptionInLinkedThread  
Convenient utilities
race_ :: MonadBaseControl IO m => m a > m b > m () #
Generalized version of race_
.
NOTE: This function discards the monadic effects besides IO in the forked computation.
concurrently :: MonadBaseControl IO m => m a > m b > m (a, b) #
Generalized version of concurrently
.
concurrently_ :: MonadBaseControl IO m => m a > m b > m () #
Generalized version of concurrently_
.
mapConcurrently :: (Traversable t, MonadBaseControl IO m) => (a > m b) > t a > m (t b) #
Generalized version of mapConcurrently
.
mapConcurrently_ :: (Foldable t, MonadBaseControl IO m) => (a > m b) > t a > m () #
Generalized version of mapConcurrently_
.
forConcurrently :: (Traversable t, MonadBaseControl IO m) => t a > (a > m b) > m (t b) #
Generalized version of forConcurrently
.
forConcurrently_ :: (Foldable t, MonadBaseControl IO m) => t a > (a > m b) > m () #
Generalized version of forConcurrently_
.
replicateConcurrently :: MonadBaseControl IO m => Int > m a > m [a] #
Generalized version of replicateConcurrently
.
replicateConcurrently_ :: MonadBaseControl IO m => Int > m a > m () #
Generalized version of replicateConcurrently_
.
newtype Concurrently m a #
Generalized version of Concurrently
.
A value of type
is an IObased operation that can be
composed with other Concurrently
m aConcurrently
values, using the Applicative
and
Alternative
instances.
Calling runConcurrently
on a value of type
will
execute the IObased lifted operations it contains concurrently, before
delivering the result of type Concurrently
m aa
.
For example
(page1, page2, page3) <runConcurrently
$ (,,)<$>
Concurrently
(getURL "url1")<*>
Concurrently
(getURL "url2")<*>
Concurrently
(getURL "url3")
Concurrently  
