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Date: Sun, 15 May 2011 11:17:31 +1000
Subject: Re: I don't understand generator.send()
From: Chris Angelico <rosuav@gmail.com>
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On Sun, May 15, 2011 at 11:05 AM, Ian Kelly <ian.g.kelly@gmail.com> wrote:
> Actually, this won't work, because the value of the "yield None" gets
> ignored. =A0Thus if you try to call send() twice in a row, the generator
> the treats second send() as if it were a next(), and it is not
> possible to have more than one item in the queue.

You're right. It needs a while loop instead of the if (and some slight
reordering):

def ints():
   i=3D0
   queue=3D[]
   while True:
       if queue:  # see other thread, this IS legal and pythonic and
quite sensible
           sent=3D(yield queue.pop(0))
       else:
           sent=3D(yield i)
           i+=3D1
       while sent is not None:
           queue.append(sent)
           sent=3D(yield None)  # This is the return value from gen.send()

That should work.

Chris Angelico