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From: Ned Batchelder <ned@nedbatchelder.com>
Subject: Re: should I transfer 'iterators' between functions?
Date: Sat, 25 Jan 2014 07:56:34 -0500
References: <6ad4232c-a8d9-4195-9edd-65c0e35923a7@googlegroups.com>
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Xref: csiph.com comp.lang.python:64743

On 1/25/14 1:37 AM, 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)
>
>

One more thing: there's no need to call iter() explicitly here.  Much 
more common than returning an iterator from a function is to return an 
iterable.  Your code will work exactly the same if you just remove the 
iter() call:

     def test():
         l = [1, 2, 3, 4, 5, 6, 7, 8]
         return l
     def main():
         for i in test():
             print(i)


-- 
Ned Batchelder, http://nedbatchelder.com