class Async::Condition

@public Since ‘stable-v1`.
A synchronization primitive, which allows fibers to wait until a particular condition is (edge) triggered.

def empty?

@returns [Boolean]
Is any fiber waiting on this notification? 
def empty?
	@waiting.empty?
end

def initialize 

def initialize
	@waiting = []
end

def signal(value = nil)

@parameter value [Object | Nil] The value to return to the waiting fibers.
Signal to a given task that it should resume operations. 
def signal(value = nil)
	waiting = @waiting
	@waiting = []
	
	waiting.each do |fiber|
		Fiber.scheduler.resume(fiber, value) if fiber.alive?
	end
	
	return nil
end

def wait

@returns [Object]
Queue up the current fiber and wait on yielding the task. 
def wait
	queue = Queue.new(Fiber.current)
	@waiting << queue
	
	Fiber.scheduler.transfer
ensure
	queue.nullify
end