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Re: should I transfer 'iterators' between functions?

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Date Sat, 25 Jan 2014 17:43:58 +1100
Subject Re: should I transfer 'iterators' between functions?
From Chris Angelico <rosuav@gmail.com>
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On Sat, Jan 25, 2014 at 5:37 PM,  <seaspeak@gmail.com> wrote:
> take the following as an example, which could work well.
> But my concern is, will list 'l' be deconstructed after function return? and then iterator point to nowhere?
>
> def test():
>     l = [1, 2, 3, 4, 5, 6, 7, 8]
>     return iter(l)
> def main():
>     for i in test():
>         print(i)

Perfectly safe. Python guarantees that nothing can ever point to
"nowhere"; everything that might be looking for something else will
hold a reference to it, so the thing referred to will hang around.

ChrisA

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Thread

should I transfer 'iterators' between functions? seaspeak@gmail.com - 2014-01-24 22:37 -0800
  Re: should I transfer 'iterators' between functions? Chris Angelico <rosuav@gmail.com> - 2014-01-25 17:43 +1100
  Re: should I transfer 'iterators' between functions? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-01-25 06:45 +0000
  Re: should I transfer 'iterators' between functions? Ned Batchelder <ned@nedbatchelder.com> - 2014-01-25 07:55 -0500
  Re: should I transfer 'iterators' between functions? Ned Batchelder <ned@nedbatchelder.com> - 2014-01-25 07:56 -0500
  Re: should I transfer 'iterators' between functions? Peter Otten <__peter__@web.de> - 2014-01-25 14:32 +0100

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