class Async::Node

def consume
	if parent = @parent and finished?
		parent.delete_child(self)
		
		if @children
			@children.each do |child|
				if child.finished?
					delete_child(child)
				else
					parent.add_child(child)
				end
			end
			
			@children = nil
		end
		
		parent.consume
	end
end