Class: Async::Waiter Deprecated

Inherits:
Object
  • Object
show all
Defined in:
lib/async/waiter.rb

Overview

Deprecated.

‘Async::Waiter` is deprecated, use `Async::Barrier` instead.

A composable synchronization primitive, which allows one task to wait for a number of other tasks to complete. It can be used in conjunction with Semaphore and/or Barrier.

Instance Method Summary collapse

Constructor Details

#initialize(parent: nil, finished: Async::Condition.new) ⇒ Waiter

Create a waiter instance.



17
18
19
20
21
22
23
24
 
# File 'lib/async/waiter.rb', line 17

def initialize(parent: nil, finished: Async::Condition.new)
  warn("`Async::Waiter` is deprecated, use `Async::Barrier` instead.", uplevel: 1, category: :deprecated) if $VERBOSE
  
  @finished = finished
  @done = []
  
  @parent = parent
end

Instance Method Details

#async(parent: (@parent or Task.current), **options, &block) ⇒ Object

Execute a child task and add it to the waiter.



28
29
30
31
32
33
34
35
 
# File 'lib/async/waiter.rb', line 28

def async(parent: (@parent or Task.current), **options, &block)
  parent.async(**options) do |task|
    yield(task)
  ensure
    @done << task
    @finished.signal
  end
end

#first(count = nil) ⇒ Object

Wait for the first ‘count` tasks to complete.



41
42
43
44
45
46
47
48
49
 
# File 'lib/async/waiter.rb', line 41

def first(count = nil)
  minimum = count || 1
  
  while @done.size < minimum
    @finished.wait
  end
  
  return @done.shift(*count)
end

#wait(count = nil) ⇒ Object

Wait for the first ‘count` tasks to complete.



53
54
55
56
57
58
59
 
# File 'lib/async/waiter.rb', line 53

def wait(count = nil)
  if count
    first(count).map(&:wait)
  else
    first.wait
  end
end