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Re: I don't understand generator.send()

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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.  Thus 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=0
   queue=[]
   while True:
       if queue:  # see other thread, this IS legal and pythonic and
quite sensible
           sent=(yield queue.pop(0))
       else:
           sent=(yield i)
           i+=1
       while sent is not None:
           queue.append(sent)
           sent=(yield None)  # This is the return value from gen.send()

That should work.

Chris Angelico

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Thread

I don't understand generator.send() see@sig.for.address (Victor Eijkhout) - 2011-05-14 19:08 -0500
  Re: I don't understand generator.send() "OKB (not okblacke)" <brenNOSPAMbarn@NObrenSPAMbarn.net> - 2011-05-15 00:38 +0000
  Re: I don't understand generator.send() Chris Angelico <rosuav@gmail.com> - 2011-05-15 10:47 +1000
    Re: I don't understand generator.send() see@sig.for.address (Victor Eijkhout) - 2011-05-14 20:40 -0500
  Re: I don't understand generator.send() Chris Rebert <crebert@ucsd.edu> - 2011-05-14 17:47 -0700
  Re: I don't understand generator.send() Ian Kelly <ian.g.kelly@gmail.com> - 2011-05-14 18:57 -0600
  Re: I don't understand generator.send() Ian Kelly <ian.g.kelly@gmail.com> - 2011-05-14 19:05 -0600
  Re: I don't understand generator.send() Chris Angelico <rosuav@gmail.com> - 2011-05-15 11:17 +1000
  Re: I don't understand generator.send() Ian Kelly <ian.g.kelly@gmail.com> - 2011-05-14 21:03 -0600

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