- 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
- data PQ a
- emptyPQ :: Ord p => (a -> p) -> PQ a
- mkPriorityQueue :: ModifyRef sr m (PQ a) => sr -> PriorityQueue m a
- mkDefaultPriorityQueue :: Ref m (PQ a) -> PriorityQueue m a
- data PriorityQueue m a
- newPriorityQueue :: (Monad m, HasRef m1, NewRef (Ref m1 (PQ a)) m (PQ a), Ord p) => (a -> p) -> m (PriorityQueue m1 a)
- newPriorityQueueBy :: (Monad m, HasRef m1, NewRef (Ref m1 (PQ a)) m (PQ a)) => (a -> a -> Ordering) -> m (PriorityQueue m1 a)
Documentation
class Monad m => Enqueue q m a | q -> a where
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 ()
Monad m => Enqueue (PriorityQueue m a) m a |
class Monad m => Dequeue q m a | q -> a where
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]
Monad m => Dequeue (PriorityQueue m a) m a |
class Monad m => DequeueWhere q m a | q -> a where
dequeueWhere :: q -> (a -> Bool) -> m (Maybe a)
Pull an item matching the given predicate out of a queue.
Monad m => DequeueWhere (PriorityQueue m a) m a |
class Monad m => PeekQueue q m a | q -> a where
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.
Monad m => PeekQueue (PriorityQueue m a) m a |
class Monad m => QueueSize q m where
Monad m => QueueSize (PriorityQueue m a) m |
mkPriorityQueue :: ModifyRef sr m (PQ a) => sr -> PriorityQueue m aSource
Build a priority queue from a modifiable reference containing
a PQ
mkDefaultPriorityQueue :: Ref m (PQ a) -> PriorityQueue m aSource
Build a priority queue using an instance of the default modifiable reference for the requested monad and value type
data PriorityQueue m a Source
A priority queue usable in the monad m
with values of type a
Monad m => QueueSize (PriorityQueue m a) m | |
Monad m => Enqueue (PriorityQueue m a) m a | |
Monad m => Dequeue (PriorityQueue m a) m a | |
Monad m => DequeueWhere (PriorityQueue m a) m a | |
Monad m => PeekQueue (PriorityQueue m a) m a |
newPriorityQueue :: (Monad m, HasRef m1, NewRef (Ref m1 (PQ a)) m (PQ a), Ord p) => (a -> p) -> m (PriorityQueue m1 a)Source
Construct a new priority queue using the specified indexing function
newPriorityQueueBy :: (Monad m, HasRef m1, NewRef (Ref m1 (PQ a)) m (PQ a)) => (a -> a -> Ordering) -> m (PriorityQueue m1 a)Source
Construct a new priority queue using a comparator function. It is the user's responsibility to ensure that this function provides a sensible order.