协同程序 过滤器

function receive (prod) –来接受数据 恢复生产者协同程序 等待他发送参数回来 local status, value = coroutine.resume(prod) return value end function send (x) –停止本协同程序 返回数据给 resume coroutine.yield(x) end function producer () –生产者协同程序 读取数据 发送给 调用 resume的函数 return coroutine.create(function () while true do local x = io.read() – produce new value send(x) end end) end function filter (prod) –过滤器 return coroutine.create(function () local line = 1 while true do local x = receive(prod) – get new value x = string.format(“%5d %s”, line, x) send(x) – send it to consumer line = line + 1 end end) end function consumer (prod) –消费者协同程序 接受数据 写屏 接受的过滤过的数据 while true do local x = receive(prod) – get new value io.write(x, “/n”) – consume new value end end p = producer() –创建生产数据的协同程序 f = filter(p) consumer(f) –or consumer(filter(producer()))