fs2-core/fs2.concurrent/Queue

Queue

trait Queue[F[_], A] extends Enqueue[F, A] with Dequeue1[F, A] with DequeueChunk1[F, Id, A] with Dequeue[F, A]

A queue of elements. Operations are all nonblocking in their implementations, but may be 'semantically' blocking. For instance, a queue may have a bound on its size, in which case enqueuing may block (be delayed asynchronously) until there is an offsetting dequeue.

A queue of elements. Operations are all nonblocking in their implementations, but may be 'semantically' blocking. For instance, a queue may have a bound on its size, in which case enqueuing may block (be delayed asynchronously) until there is an offsetting dequeue.

Companion
object
trait Dequeue[F, A]
trait DequeueChunk1[F, Id, A]
trait Dequeue1[F, A]
trait Enqueue[F, A]
class Object
trait Matchable
class Any
trait InspectableQueue[F, A]

Value members

Concrete methods

def imap[B](f: A => B)(g: B => A)(F: Functor[F]): Queue[F, B]

Returns an alternate view of this Queue where its elements are of type B, given two functions, A => B and B => A.

Returns an alternate view of this Queue where its elements are of type B, given two functions, A => B and B => A.

Inherited methods

def dequeue: Stream[F, A]

Dequeues elements from the queue.

Dequeues elements from the queue.

Inherited from
Dequeue
def dequeue1: F[A]

Dequeues one A from this queue. Completes once one is ready.

Dequeues one A from this queue. Completes once one is ready.

Inherited from
Dequeue1
def dequeueBatch: (F, Int) => A

Provides a pipe that converts a stream of batch sizes in to a stream of elements by dequeuing batches of the specified size.

Provides a pipe that converts a stream of batch sizes in to a stream of elements by dequeuing batches of the specified size.

Inherited from
Dequeue
def dequeueChunk(maxSize: Int): Stream[F, A]

Dequeues elements from the queue, ensuring elements are dequeued in chunks not exceeding maxSize.

Dequeues elements from the queue, ensuring elements are dequeued in chunks not exceeding maxSize.

Inherited from
Dequeue
def dequeueChunk1(maxSize: Int): F[Id[Chunk[A]]]

Dequeues one Chunk[A] with no more than maxSize elements. Completes once one is ready.

Dequeues one Chunk[A] with no more than maxSize elements. Completes once one is ready.

Inherited from
DequeueChunk1
def enqueue: (F, A) => Unit

Enqueues each element of the input stream to this queue by calling enqueue1 on each element.

Enqueues each element of the input stream to this queue by calling enqueue1 on each element.

Inherited from
Enqueue
def enqueue1(a: A): F[Unit]

Enqueues one element to this Queue. If the queue is full this waits until queue has space.

Enqueues one element to this Queue. If the queue is full this waits until queue has space.

This completes after a has been successfully enqueued to this Queue

Inherited from
Enqueue
def offer1(a: A): F[Boolean]

Offers one element to this Queue.

Offers one element to this Queue.

Evaluates to false if the queue is full, indicating the a was not queued up. Evaluates to true if the a was queued up successfully.

Value Params
a

A to enqueue

Inherited from
Enqueue
def tryDequeue1: F[Option[A]]

Tries to dequeue a single element. Unlike dequeue1, this method does not semantically block until a chunk is available - instead, None is returned immediately.

Tries to dequeue a single element. Unlike dequeue1, this method does not semantically block until a chunk is available - instead, None is returned immediately.

Inherited from
Dequeue1
def tryDequeueChunk1(maxSize: Int): F[Option[Id[Chunk[A]]]]

Tries to dequeue a single chunk of no more than max size elements. Unlike dequeueChunk1, this method does not semantically block until a chunk is available - instead, None is returned immediately.

Tries to dequeue a single chunk of no more than max size elements. Unlike dequeueChunk1, this method does not semantically block until a chunk is available - instead, None is returned immediately.

Inherited from
DequeueChunk1