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To: Fabien <fabien.maussion@gmail.com>
cc: python-list@python.org, lac@openend.se
From: Laura Creighton <lac@openend.se>
Subject: Re: zip as iterator and bad/good practices
In-Reply-To: Message from Fabien <fabien.maussion@gmail.com> of "Fri, 12 Jun 2015 17:00:09 +0200." <mles66$sk2$1@speranza.aioe.org>
References: <mles66$sk2$1@speranza.aioe.org>
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Date: Fri, 12 Jun 2015 22:34:34 +0200
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Xref: csiph.com comp.lang.python:92552

The real problem is removing things from lists when you are iterating
over them, not adding things to the end of lists.

Python 2.7.9 (default, Mar  1 2015, 12:57:24)
[GCC 4.9.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> mylist = [1,2,3]
>>> for i in mylist:
...     print i
...     mylist.remove(i)
...
1
3
>>> mylist
[2]

Most people expect 1 2 and 3 to get printed, and mylist to be empty at
the end of this loop.

Laura