| Safe Haskell | Safe-Inferred |
|---|
Data.Queue.Classes
- class Monad m => NewFifo q m where
- newFifo :: m q
- class Monad m => DefaultFifo q m a | q -> a, m a -> q
- class Monad m => Enqueue q m a | q -> a where
- enqueue :: q -> a -> m ()
- enqueueBatch :: q -> [a] -> m ()
- class Monad m => Dequeue q m a | q -> a where
- dequeue :: q -> m (Maybe a)
- dequeueBatch :: q -> m [a]
- class Monad m => DequeueWhere q m a | q -> a where
- dequeueWhere :: q -> (a -> Bool) -> m (Maybe a)
- class Monad m => PeekQueue q m a | q -> a where
- peekQueue :: q -> m [a]
- peekQueueTaking :: Int -> q -> m [a]
- class Monad m => QueueSize q m where
Documentation
class Monad m => DefaultFifo q m a | q -> a, m a -> q
A type class carrying an altered set of functional dependencies used to constrain queues when the type of the queue never escapes far enough for a more deliberate choice to be made.
Instances
| Monad IO => DefaultFifo (TChan a) IO a | |
| Monad STM => DefaultFifo (TChan a) STM a |
class Monad m => Enqueue q m a | q -> a where
Methods
enqueue :: q -> a -> m ()
Put an item into a queue. May block while trying to do so.
No constraint is placed on the behavior of the queue except that
every item put in really ought to come out sometime before
dequeue returns a Nothing.
enqueueBatch :: q -> [a] -> m ()
class Monad m => Dequeue q m a | q -> a where
Methods
Pull an item out of a queue. Should not block. No ordering
constraints are implied other than that any item that went into
the queue really ought to come out before dequeue returns
Nothing.
dequeueBatch :: q -> m [a]
class Monad m => DequeueWhere q m a | q -> a where
Methods
dequeueWhere :: q -> (a -> Bool) -> m (Maybe a)
Pull an item matching the given predicate out of a queue.
class Monad m => PeekQueue q m a | q -> a where
Methods
peekQueue :: q -> m [a]
return the whole contents of the queue (if possible) without altering the queue's contents. Obviously in cases where this can't be done lazily this can be a very expensive operation.
peekQueueTaking :: Int -> q -> m [a]
peek a specified number of items off the queue. The default implementation is hideously wasteful in cases where peekQueue is not able to get the contents lazily.