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Re: for...else

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From Todd <toddrjen@gmail.com>
Date Tue, 2 Jun 2015 13:49:09 +0200
Subject Re: for...else
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I think there is essentially zero chance of that.  My understanding is that
Guido regrets having "else" to begin with.

But this should work

broken = True
for x in it:
    if complicated_calculation_1():
        break
    complicated_calculation_2()
    if complicated_calculation_3():
        break
else:
    broken = False
if broken:
    cleanup()


On Tue, Jun 2, 2015 at 1:26 PM, acdr <mail.acdr@gmail.com> wrote:

> Hi,
>
> Currently, in various places in my code, I have the equivalent of:
>
> for x in it:
>     if complicated_calculation_1():
>         cleanup()
>         break
>     complicated_calculation_2()
>     if complicated_calculation_3():
>         cleanup()
>         break
>
> Obviously, I'm repeating myself by having two separate calls to
> cleanup(). I can't really see a nicer way to do this. (Though I see
> plenty of non-nice ways to do this, such as adding "broken = True" in
> front of every "break", and then after the loop is done, have an "if
> broken" section.) Other solutions that I'm not particularly fond of
> can be found on stackexchange, where someone else is trying to do the
> same thing:
> http://stackoverflow.com/questions/3296044/opposite-of-python-for-else
>
> I'm wondering if there is a demand for expanding the "for...else"
> functionality to be expanded also have a block of code that only gets
> called if the loop is broken out of. I.e.:
>
> for x in it:
>     ...
> then:
>     # "break" was called
>     ...
> else:
>     # "break was not called
>     ...
> --
> https://mail.python.org/mailman/listinfo/python-list
>

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Re: for...else Todd <toddrjen@gmail.com> - 2015-06-02 13:49 +0200

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