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Re: Try-except-finally paradox

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On 2014.01.29 23:56, Jessica Ross wrote:
> I found something like this in a StackOverflow discussion.
>>>> def paradox():
> ...     try:
> ...             raise Exception("Exception raised during try")
> ...     except:
> ...             print "Except after try"
> ...             return True
> ...     finally:
> ...             print "Finally"
> ...             return False
> ...     return None
> ... 
>>>> return_val = paradox()
> Except after try
> Finally
>>>> return_val
> False
> 
> I understand most of this.
> What I don't understand is why this returns False rather than True. Does the finally short-circuit the return in the except block?
> 
My guess would be that the interpreter doesn't let the finally block get skipped under any circumstances, so the return value gets set to
True, but then it forces the finally block to be run before returning, which changes the return value to False.

-- 
CPython 3.3.2 | Windows NT 6.2.9200 / FreeBSD 10.0

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Thread

Try-except-finally paradox Jessica Ross <deathweasel@gmail.com> - 2014-01-29 21:56 -0800
  Re: Try-except-finally paradox Ian Kelly <ian.g.kelly@gmail.com> - 2014-01-29 23:23 -0700
  Re: Try-except-finally paradox Andrew Berg <robotsondrugs@gmail.com> - 2014-01-30 00:33 -0600
    Re: Try-except-finally paradox Rotwang <sg552@hotmail.co.uk> - 2014-01-30 18:12 +0000
      Re: Try-except-finally paradox Ethan Furman <ethan@stoneleaf.us> - 2014-01-30 10:30 -0800
  Re: Try-except-finally paradox wxjmfauth@gmail.com - 2014-01-29 22:59 -0800
  Re:Try-except-finally paradox Dave Angel <davea@davea.name> - 2014-01-30 07:05 -0500
  Re: Try-except-finally paradox Chris Angelico <rosuav@gmail.com> - 2014-01-31 00:02 +1100
  Re: Try-except-finally paradox MRAB <python@mrabarnett.plus.com> - 2014-01-30 13:11 +0000
  Re: Try-except-finally paradox Chris Angelico <rosuav@gmail.com> - 2014-01-31 00:19 +1100
  Re: Try-except-finally paradox Terry Reedy <tjreedy@udel.edu> - 2014-01-31 00:26 -0500
  Re: Try-except-finally paradox Göktuğ Kayaalp <self@gkayaalp.com> - 2014-02-01 03:58 +0200

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