A queue with different kinds of values, described by t, where each kind can have a higher or lower priority than other kinds, as described by the queuePrios field.

Constructors

Queue
Fields queueData :: Vector (TVar (Q a)) queueIndices :: Map t Int queuePrios :: Map t Prio

defaultPrios :: EnumBounded t => Map t Prio #

Default priorities for the enumeration of job types t: everyone at 0.

newQueue :: EnumBounded t => Map t Prio -> IO (Queue t a) #

Create a new queue that'll apply the given priorities

addQueue :: Ord t => t -> a -> Queue t a -> STM () #

Add a new element to the queue, with the given kind.

deleteQueue :: (Eq a, Ord t) => t -> a -> Queue t a -> STM () #

debugDumpQueue :: (Enum t, Bounded t, Ord t) => Queue t a -> STM [(t, a)] #

Dump the contents of the queue, for debugging purposes.

type Picker a = [(a, STM ())] -> STM (a, STM ()) #

popQueue :: forall a t. Ord t => Picker a -> Queue t a -> IO (Maybe a) #

Figure out the candidates for being popped from the various queues. We always look at highest priority queues first, and will pick between equal priority items of different queues (candidates, elements of the returned lists) by choosing the one that was queued first.

queueRunner :: Ord t => Picker a -> (a -> IO ()) -> Queue t a -> IO () #

A ready-to-use runner that pops the highest priority item off the queue and processes it using the given function.

newQueueWithRunners #

Arguments

:: EnumBounded t
=> Int	number of runners
-> Map t Prio	priorities
-> Picker a	how to pick between equal priority items
-> (a -> IO ())	what to do with each item
-> IO (Queue t a, [IO ()])

Create a queue and n runner actions for it, with the given priorities for the runners to apply when picking a new item.