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Re: Generator using item[n-1] + item[n] memory

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On 15/02/2014 03:31, Nick Timkovich wrote:
> OK, now the trick; adding `data = None` inside the generator works, but
> in my actual code I wrap my generator inside of `enumerate()`, which
> seems to obviate the "fix".  Can I get it to play nice or am I forced to
> count manually. Is that a feature?
>
>
> On Fri, Feb 14, 2014 at 9:21 PM, Roy Smith <roy@panix.com
> <mailto:roy@panix.com>> wrote:
>
>     In article <mailman.6952.1392433921.18130.python-list@python.org
>     <mailto:mailman.6952.1392433921.18130.python-list@python.org>>,
>       Nick Timkovich <prometheus235@gmail.com
>     <mailto:prometheus235@gmail.com>> wrote:
>
>      > Ah, I think I was equating `yield` too closely with `return` in
>     my head.
>      >  Whereas `return` results in the destruction of the function's
>     locals,
>      > `yield` I should have known keeps them around, a la C's `static`
>     functions.
>      >  Many thanks!
>
>     It's not quite like C's static.  With C's static, the static variables
>     are per-function.  In Python, yield creates a context per invocation.
>     Thus, I can do
>
>     def f():
>          for i in range(10000):
>              yield i
>
>     g1 = f()
>     g2 = f()
>     print g1.next()
>     print g1.next()
>     print g1.next()
>     print g2.next()
>     print g1.next()
>
>
>     which prints 0, 1, 2, 0, 3.  There's two contexts active at the same
>     time, with a distinct instance of "i" in each one.
>     --
>     https://mail.python.org/mailman/listinfo/python-list
>

Nick, please don't top post on this list, thanks.

-- 
My fellow Pythonistas, ask not what our language can do for you, ask 
what you can do for our language.

Mark Lawrence

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Re: Generator using item[n-1] + item[n] memory Roy Smith <roy@panix.com> - 2014-02-14 22:21 -0500
  Re: Generator using item[n-1] + item[n] memory Nick Timkovich <prometheus235@gmail.com> - 2014-02-14 21:31 -0600
  Re: Generator using item[n-1] + item[n] memory Ian Kelly <ian.g.kelly@gmail.com> - 2014-02-15 00:27 -0700
  Re: Generator using item[n-1] + item[n] memory Chris Angelico <rosuav@gmail.com> - 2014-02-15 18:41 +1100
  Re: Generator using item[n-1] + item[n] memory Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-02-15 11:03 +0000
  Re: Generator using item[n-1] + item[n] memory Peter Otten <__peter__@web.de> - 2014-02-15 12:27 +0100
  Re: Generator using item[n-1] + item[n] memory Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-02-15 12:28 +0000

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