User of a Fiber block to create a simple producer consumer thing.

producer_consumer.rb

@b = nil
@x = nil
@y = nil
@z = nil

def producer
  Fiber.new do 
    loop do
      @b = rand()
      Fiber.yield #or consumer resume

      @b = rand()
      Fiber.yield 
    end
  end
end

def consumer
  Fiber.new do
    loop do
      @x = @b
      producer.resume

      @y = @b
      producer.resume

      @z = @b
      producer.resume

      puts "x = #{@x} y = #{@y} z = #{@z}"
    end
  end
end

consumer.resume