distributed-process-0.2.3.0: Cloud Haskell: Erlang-style concurrency in Haskell

Safe HaskellNone

Control.Distributed.Process.Internal.Primitives

Contents

Description

Cloud Haskell primitives

We define these in a separate module so that we don't have to rely on the closure combinators

Synopsis

Basic messaging

send :: Serializable a => ProcessId -> a -> Process ()Source

Send a message

expect :: forall a. Serializable a => Process aSource

Wait for a message of a specific type

Channels

newChan :: Serializable a => Process (SendPort a, ReceivePort a)Source

Create a new typed channel

sendChan :: Serializable a => SendPort a -> a -> Process ()Source

Send a message on a typed channel

receiveChan :: Serializable a => ReceivePort a -> Process aSource

Wait for a message on a typed channel

mergePortsBiased :: Serializable a => [ReceivePort a] -> Process (ReceivePort a)Source

Merge a list of typed channels.

The result port is left-biased: if there are messages available on more than one port, the first available message is returned.

mergePortsRR :: Serializable a => [ReceivePort a] -> Process (ReceivePort a)Source

Like mergePortsBiased, but with a round-robin scheduler (rather than left-biased)

Advanced messaging

data Match b Source

Opaque type used in receiveWait and receiveTimeout

receiveWait :: [Match b] -> Process bSource

Test the matches in order against each message in the queue

receiveTimeout :: Int -> [Match b] -> Process (Maybe b)Source

Like receiveWait but with a timeout.

If the timeout is zero do a non-blocking check for matching messages. A non-zero timeout is applied only when waiting for incoming messages (that is, after we have checked the messages that are already in the mailbox).

match :: forall a b. Serializable a => (a -> Process b) -> Match bSource

Match against any message of the right type

matchIf :: forall a b. Serializable a => (a -> Bool) -> (a -> Process b) -> Match bSource

Match against any message of the right type that satisfies a predicate

matchUnknown :: Process b -> Match bSource

Remove any message from the queue

Process management

terminate :: Process aSource

Terminate (throws a ProcessTerminationException)

data ProcessTerminationException Source

Thrown by terminate

Constructors

ProcessTerminationException 

Instances

getSelfPid :: Process ProcessIdSource

Our own process ID

getSelfNode :: Process NodeIdSource

Get the node ID of our local node

Monitoring and linking

link :: ProcessId -> Process ()Source

Link to a remote process (asynchronous)

Note that link provides unidirectional linking (see spawnSupervised). Linking makes no distinction between normal and abnormal termination of the remote process.

unlink :: ProcessId -> Process ()Source

Remove a link (synchronous)

monitor :: ProcessId -> Process MonitorRefSource

Monitor another process (asynchronous)

unmonitor :: MonitorRef -> Process ()Source

Remove a monitor (synchronous)

Logging

say :: String -> Process ()Source

Log a string

say message sends a message (time, pid of the current process, message) to the process registered as logger. By default, this process simply sends the string to stderr. Individual Cloud Haskell backends might replace this with a different logger process, however.

Registry

register :: String -> ProcessId -> Process ()Source

Register a process with the local registry (asynchronous).

The process to be registered does not have to be local itself.

unregister :: String -> Process ()Source

Remove a process from the local registry (asynchronous).

whereis :: String -> Process (Maybe ProcessId)Source

Query the local process registry (synchronous).

nsend :: Serializable a => String -> a -> Process ()Source

Named send to a process in the local registry (asynchronous)

registerRemote :: NodeId -> String -> ProcessId -> Process ()Source

Register a process with a remote registry (asynchronous).

The process to be registered does not have to live on the same remote node.

unregisterRemote :: NodeId -> String -> Process ()Source

Remove a process from a remote registry (asynchronous).

whereisRemote :: NodeId -> String -> Process (Maybe ProcessId)Source

Query a remote process registry (synchronous)

whereisRemoteAsync :: NodeId -> String -> Process ()Source

Query a remote process registry (asynchronous)

Reply will come in the form of a WhereIsReply message

nsendRemote :: Serializable a => NodeId -> String -> a -> Process ()Source

Named send to a process in a remote registry (asynchronous)

Closures

unClosure :: forall a. Typeable a => Closure a -> Process aSource

Deserialize a closure

Exception handling

catch :: Exception e => Process a -> (e -> Process a) -> Process aSource

Lift catch

mask :: ((forall a. Process a -> Process a) -> Process b) -> Process bSource

Lift mask

onException :: Process a -> Process b -> Process aSource

Lift onException

bracket :: Process a -> (a -> Process b) -> (a -> Process c) -> Process cSource

Lift bracket

bracket_ :: Process a -> Process b -> Process c -> Process cSource

Lift bracket_

finally :: Process a -> Process b -> Process aSource

Lift finally

Auxiliary API

expectTimeout :: forall a. Serializable a => Int -> Process (Maybe a)Source

Like expect but with a timeout

spawnAsync :: NodeId -> Closure (Process ()) -> Process SpawnRefSource

Asynchronous version of spawn

(spawn is defined in terms of spawnAsync and expect)

linkNode :: NodeId -> Process ()Source

Link to a node

linkPort :: SendPort a -> Process ()Source

Link to a channel (send port)

unlinkNode :: NodeId -> Process ()Source

Remove a node link (synchronous)

unlinkPort :: SendPort a -> Process ()Source

Remove a channel (send port) link (synchronous)

monitorNode :: NodeId -> Process MonitorRefSource

Monitor a node

monitorPort :: forall a. Serializable a => SendPort a -> Process MonitorRefSource

Monitor a typed channel