class Queue
A queue which allows items to be processed in order.
It has a compatible interface with class Async::Notification
and class Async::Condition
, except that it's multi-value.
Signature
- public
Since Async v1.
Definitions
def initialize(parent: nil, available: Notification.new)
Create a new queue.
Signature
-
parameter
parent
Interface(:async) | Nil
The parent task to use for async operations.
-
parameter
available
Notification
The notification to use for signaling when items are available.
Implementation
def initialize(parent: nil, available: Notification.new)
@items = []
@parent = parent
@available = available
end
attr :items
Signature
-
attribute
Array
The items in the queue.
def size
Signature
-
returns
Integer
The number of items in the queue.
Implementation
def size
@items.size
end
def empty?
Signature
-
returns
Boolean
Whether the queue is empty.
Implementation
def empty?
@items.empty?
end
def push(item)
Add an item to the queue.
Implementation
def push(item)
@items << item
@available.signal unless self.empty?
end
def enqueue(*items)
Add multiple items to the queue.
Implementation
def enqueue(*items)
@items.concat(items)
@available.signal unless self.empty?
end
def dequeue
Remove and return the next item from the queue.
Implementation
def dequeue
while @items.empty?
@available.wait
end
@items.shift
end
def async(parent: (@parent or Task.current), **options, &block)
- asynchronous
Process each item in the queue.
Signature
- asynchronous
Executes the given block concurrently for each item.
-
parameter
arguments
Array
The arguments to pass to the block.
-
parameter
parent
Interface(:async) | Nil
The parent task to use for async operations.
-
parameter
options
Hash
The options to pass to the task.
-
yields
{|task| ...}
When the system is idle, the block will be executed in a new task.
Implementation
def async(parent: (@parent or Task.current), **options, &block)
while item = self.dequeue
parent.async(item, **options, &block)
end
end
def each
Enumerate each item in the queue.
Implementation
def each
while item = self.dequeue
yield item
end
end
def signal(value = nil)
Signal the queue with a value, the same as #enqueue
.
Implementation
def signal(value = nil)
self.enqueue(value)
end
def wait
Wait for an item to be available, the same as #dequeue
.
Implementation
def wait
self.dequeue
end