Control.Concurrent.STM.TPQueue

A transactional priority queue, based on a Finger Tree.

Documentation

data TPQueue k v

TPQueue is an unbounded priority queue based on a Finger Tree.

newTPQueue :: Ord k => STM (TPQueue k v)

Build a new TPQueue.

newTPQueueIO :: Ord k => IO (TPQueue k v)

IO version of newTPQueue. This is useful for creating top-level TPQueues using unsafePerformIO, because using atomically inside unsafePerformIO isn't possible.

writeTPQueue :: Ord k => TPQueue k v -> k -> v -> STM ()

Write a value to a TPQueue.

readTPQueue :: Ord k => TPQueue k v -> STM v

Read the next minimal value from a TPQueue.

tryReadTPQueue :: Ord k => TPQueue k v -> STM (Maybe v)

A version of readTPQueue that does not retry, but returns Nothing instead if no value is available.

peekTPQueue :: Ord k => TPQueue k v -> STM v

Get the next minimal value from a TPQueue without removing it.

tryPeekTPQueue :: Ord k => TPQueue k v -> STM (Maybe v)

A version of peekTPQueue that does not retry, but returns Nothing instead if no value is available.

isEmptyTPQueue :: Ord k => TPQueue k v -> STM Bool

Returns True if the TPQueue is empty.