python - 我可以简化这个 "delayed"python 生成器吗？

Question

我想要一个生成器来返回我在以下迭代中发送给它的内容:

>>>g = delayed_generator()
>>>g.send(None)

>>>g.send('this')

>>>g.send('is')
'this'
>>>g.send('delayed')
'is'
>>>g.send('!')
'delayed'

我想出了一个涉及三个内部变量的解决方案，我想知道是否有更简单的方法来实现它。这是我的解决方案:

def delayed_generator():
    y = None
    z = None
    while True:
        x = yield y
        y=x
        y = yield z
        z=y
        z = yield x
        x=z

Answer 1

你可以保留一个队列:

def delayed_generator():
     q = [None, None]
     while True:
         x = yield q.pop(0)
         q.append(x)

g = delayed_generator()
g.send(None), g.send('this'), g.send('is'), g.send('delayed'), g.send('!')

返回

(None, None, 'this', 'is', 'delayed')