Language.Embedded.Concurrent

Basic concurrency primitives.

Documentation

data ThreadId

Constructors

TIDEval ThreadId (Flag ())

TIDComp TID

Instances

Show ThreadId

type ChanBound = Word16

Maximum number of elements in some bounded channel.

data Chan t a

A bounded channel.

Constructors

ChanEval (BoundedChan a) (IORef Bool) (IORef Bool)

ChanComp CID

data ThreadCMD fs a

Instances

HFunctor * * ((,) k ((,) k *)) (ThreadCMD k k)

HBifunctor * k ((,) k *) (ThreadCMD (k -> *) k)

(:<:) ((,) (* -> *) ((,) (k -> *) ((,) k1 *))) * (ThreadCMD (k -> *) k1) instr => Reexpressible k ((,) k *) (ThreadCMD (k -> *) k) instr

InterpBi ((,) k *) * (ThreadCMD (* -> *) k) IO (Param1 k pred)

data ChanCMD fs a

Instances

HFunctor k * ((,) (* -> *) ((,) (* -> Constraint) *)) (ChanCMD (k -> *))

HBifunctor * * ((,) (* -> Constraint) *) (ChanCMD (* -> *))

(:<:) ((,) (* -> *) ((,) (* -> *) ((,) (* -> Constraint) *))) * (ChanCMD (* -> *)) instr => Reexpressible * ((,) (* -> Constraint) *) (ChanCMD (* -> *)) instr

InterpBi ((,) (* -> Constraint) *) * (ChanCMD (* -> *)) IO (Param1 (* -> Constraint) pred)

data Closeable

data Uncloseable

fork :: ThreadCMD :<: instr => ProgramT instr (Param2 exp pred) m () -> ProgramT instr (Param2 exp pred) m ThreadId

Fork off a computation as a new thread.

forkWithId :: ThreadCMD :<: instr => (ThreadId -> ProgramT instr (Param2 exp pred) m ()) -> ProgramT instr (Param2 exp pred) m ThreadId

Fork off a computation as a new thread, with access to its own thread ID.

asyncKillThread :: ThreadCMD :<: instr => ThreadId -> ProgramT instr (Param2 exp pred) m ()

Forcibly terminate a thread, then continue execution immediately.

killThread :: (ThreadCMD :<: instr, Monad m) => ThreadId -> ProgramT instr (Param2 exp pred) m ()

Forcibly terminate a thread. Blocks until the thread is actually dead.

waitThread :: ThreadCMD :<: instr => ThreadId -> ProgramT instr (Param2 exp pred) m ()

Wait for a thread to terminate.

newChan :: (pred a, ChanCMD :<: instr) => exp ChanBound -> ProgramT instr (Param2 exp pred) m (Chan Uncloseable a)

Create a new channel. Writing a reference type to a channel will copy the reference into the queue, not its contents.

We'll likely want to change this, actually copying arrays and the like into the queue instead of sharing them across threads.

newCloseableChan :: (pred a, ChanCMD :<: instr) => exp ChanBound -> ProgramT instr (Param2 exp pred) m (Chan Closeable a)

readChan :: (pred a, FreeExp exp, VarPred exp a, ChanCMD :<: instr, Monad m) => Chan t a -> ProgramT instr (Param2 exp pred) m (exp a)

Read an element from a channel. If channel is empty, blocks until there is an item available. If closeChan has been called on the channel *and* if the channel is empty, readChan returns an undefined value immediately.

writeChan :: (pred a, FreeExp exp, VarPred exp Bool, ChanCMD :<: instr, Monad m) => Chan t a -> exp a -> ProgramT instr (Param2 exp pred) m (exp Bool)

Write a data element to a channel. If closeChan has been called on the channel, all calls to writeChan become non-blocking no-ops and return False, otherwise returns True.

closeChan :: ChanCMD :<: instr => Chan Closeable a -> ProgramT instr (Param2 exp pred) m ()

Close a channel. All subsequent write operations will be no-ops. After the channel is drained, all subsequent read operations will be no-ops as well.

lastChanReadOK :: (FreeExp exp, VarPred exp Bool, ChanCMD :<: instr, Monad m) => Chan Closeable a -> ProgramT instr (Param2 exp pred) m (exp Bool)

When readChan was last called on the given channel, did the read succeed? Always returns True unless closeChan has been called on the channel. Always returns True if the channel has never been read.