Queue

cats.effect.std.Queue

See theQueue companion object

abstract class Queue[F[_], A] extends QueueSource[F, A] with QueueSink[F, A]

A purely functional, concurrent data structure which allows insertion and retrieval of elements of type A in a first-in-first-out (FIFO) manner.

Depending on the type of queue constructed, the Queue#offer operation can block semantically until sufficient capacity in the queue becomes available.

The Queue#take operation semantically blocks when the queue is empty.

The Queue#tryOffer and Queue#tryTake allow for usecases which want to avoid fiber blocking a fiber.

Attributes

Companion:: object
Source:: Queue.scala
Graph
Supertypes: trait QueueSink[F, A]
trait QueueSource[F, A]
class Object
trait Matchable
class Any
Known subtypes: trait Dequeue[F, A]
Self type: Queue[F, A]

Members list

Concise view

Value members

Concrete methods

Modifies the context in which this queue is executed using the natural transformation f.

Attributes

Returns:: a queue in the new context obtained by mapping the current one using f
Source:: Queue.scala

Inherited methods

Enqueues the given element at the back of the queue, possibly fiber blocking until sufficient capacity becomes available.

Attributes

a: the element to be put at the back of the queue
Inherited from:: QueueSink
Source:: Queue.scala

Attributes

Inherited from:: QueueSource
Source:: Queue.scala

Dequeues an element from the front of the queue, possibly fiber blocking until an element becomes available.

Attributes

Inherited from:: QueueSource
Source:: Queue.scala

Attempts to enqueue the given element at the back of the queue without semantically blocking.

Attributes

a: the element to be put at the back of the queue
Returns:: an effect that describes whether the enqueuing of the given element succeeded without blocking
Inherited from:: QueueSink
Source:: Queue.scala

Attempts to enqueue the given elements at the back of the queue without semantically blocking. If an item in the list cannot be enqueued, the remaining elements will be returned. This is a convenience method that recursively runs tryOffer and does not offer any additional performance benefits.

Attributes

list: the elements to be put at the back of the queue
Returns:: an effect that contains the remaining valus that could not be offered.
Inherited from:: QueueSink
Source:: Queue.scala

Attempts to dequeue an element from the front of the queue, if one is available without fiber blocking.

Attributes

Returns:: an effect that describes whether the dequeueing of an element from the queue succeeded without blocking, with None denoting that no element was available
Inherited from:: QueueSource
Source:: Queue.scala

Attempts to dequeue elements from the front of the queue, if they are available without semantically blocking. This method does not guarantee any additional performance benefits beyond simply recursively calling tryTake, though some implementations will provide a more efficient implementation.

Attributes

maxN: The max elements to dequeue. Passing None will try to dequeue the whole queue.
Returns:: an effect that contains the dequeued elements
Inherited from:: QueueSource
Source:: Queue.scala

Generated with