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Re: Iterator, modify data in loop body

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On Sat, Sep 13, 2014 at 5:01 PM, Michael Welle <mwe012008@gmx.net> wrote:
> ideed, this works for the minimal example. In a real application list
> comprehension might be a bit unhandy, because there is a lot of code
> involved.

Sure. Sometimes, cutting something down for posting makes a completely
different solution possible, and that doesn't much help. :)

> It depends on the use case I think. For some algorithms it feels natural
> to just append at the end of the list while consuming elements from the
> front. I think a deque supports that as well.

In that case, don't iterate over the list at all. Do something like this:

while lst:
    element = lst.pop(0)
    # work with element
    lst.append(new_element)

There's no mutation-while-iterating here, and it's clear that you'll
keep going until there's absolutely nothing left.

ChrisA

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Iterator, modify data in loop body Michael Welle <mwe012008@gmx.net> - 2014-09-13 08:09 +0200
  Re: Iterator, modify data in loop body Chris Angelico <rosuav@gmail.com> - 2014-09-13 16:22 +1000
    Re: Iterator, modify data in loop body Michael Welle <mwe012008@gmx.net> - 2014-09-13 09:01 +0200
      Re: Iterator, modify data in loop body Chris Angelico <rosuav@gmail.com> - 2014-09-13 17:22 +1000
        Re: Iterator, modify data in loop body Michael Welle <mwe012008@gmx.net> - 2014-09-13 09:39 +0200
          Re: Iterator, modify data in loop body Ian Kelly <ian.g.kelly@gmail.com> - 2014-09-13 09:27 -0600
            Re: Iterator, modify data in loop body Michael Welle <mwe012008@gmx.net> - 2014-09-13 18:58 +0200
          Re: Iterator, modify data in loop body Chris Angelico <rosuav@gmail.com> - 2014-09-14 01:32 +1000
        Re: Iterator, modify data in loop body Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2014-09-16 10:49 +0200
          Re: Iterator, modify data in loop body Chris Angelico <rosuav@gmail.com> - 2014-09-17 01:19 +1000
  Re: Iterator, modify data in loop body Peter Otten <__peter__@web.de> - 2014-09-13 09:34 +0200
    Re: Iterator, modify data in loop body Michael Welle <mwe012008@gmx.net> - 2014-09-13 09:55 +0200

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