Events.RefQueue

RefQueue are standard non-functional queues using pointers (aka IORefs). Events can be deleted asynchronously, but this is done only by nulling the cell they are contained in, otherwise we would need to double-link. Other operations, IE the push and pop function must not occur on the same queue concurrently.

Although the queues are impure, we return the new queue to be used in future after push and search operations.

RefQueue are intended for use for queues of guarded strings, hence the specialised implementation.

Documentation

data RefQueue a

newRefQueue :: IO (RefQueue a)

pushRefQueue :: RefQueue a -> a -> IO (RefQueue a, IO ())

searchRefQueue :: RefQueue a -> (a -> Bool) -> IO (Maybe (a, IO (RefQueue a)), RefQueue a)