Control.Monad.Queue.Class

Documentation

class Monad q => MonadQueue e q | q -> e where

Methods

enQ :: e -> q ()

Enqueue an element to a queue

deQ :: q (Maybe e)

Dequeue an element, returns Nothing if the queue is empty.

deQs :: Integral maxlen => maxlen -> q [e]

Dequeue up to maxlen elements.

peekQ :: q (Maybe e)

Examines the front element of the queue without removing it.

peekQs :: Integral maxlen => maxlen -> q [e]

Examines up to maxlen elements of the queue without removing them.

peekQn :: Integral index => index -> q (Maybe e)

Examines the element currently at position index, indexing starts at 0.

lenQ :: Integral len => q len

Returns the current length of the queue

Instances

MonadQueue e (Q e)

MonadQueue e (Q w e)