Re: try/except/finally

From	Roy Smith <roy@panix.com>
Newsgroups	comp.lang.python
Subject	Re: try/except/finally
Date	2014-06-06 13:39 -0400
Organization	PANIX Public Access Internet and UNIX, NYC
Message-ID	<roy-04A043.13393106062014@news.panix.com> (permalink)
References	<0a89c96d-de62-42ad-be48-6107ce10d215@googlegroups.com>

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In article <0a89c96d-de62-42ad-be48-6107ce10d215@googlegroups.com>,
 Frank B <fbicknel@gmail.com> wrote:

> Ok; this is a bit esoteric.
> 
> So finally is executed regardless of whether an exception occurs, so states 
> the docs.
> 
> But, I thought, if I <return> from my function first, that should take 
> precedence.
> 
> au contraire
> 
> Turns out that if you do this:
> 
> try:
>   failingthing()
> except FailException:
>   return 0
> finally:
>   return 1
> 
> Then finally really is executed regardless... even though you told it to 
> return.
> 
> That seems odd to me.

That's exactly what it's supposed to do.  The idea of finally is, "No 
matter what else happens, including calling sys.exit(), make sure this 
code executed".  It's typically used to release some critical resource 
which was acquired in the body of the try block.

https://docs.python.org/2/reference/compound_stmts.html#the-try-statement
 says:

When a return, break or continue statement is executed in the try suite 
of a try...finally statement, the finally clause is also executed Śon 
the way out.ą

The only way I can think of to bypass a finally block would be to call 
os._exit(), or send yourself a kill signal.

Thread

try/except/finally Frank B <fbicknel@gmail.com> - 2014-06-06 10:30 -0700
  Re: try/except/finally Roy Smith <roy@panix.com> - 2014-06-06 13:39 -0400
    Re: try/except/finally Frank B <fbicknel@gmail.com> - 2014-06-06 10:47 -0700
      Re: try/except/finally Ned Batchelder <ned@nedbatchelder.com> - 2014-06-06 14:22 -0400
      Re: try/except/finally Ethan Furman <ethan@stoneleaf.us> - 2014-06-07 15:49 -0700
      Re: try/except/finally Chris Angelico <rosuav@gmail.com> - 2014-06-08 09:47 +1000
        Re: try/except/finally Roy Smith <roy@panix.com> - 2014-06-07 20:12 -0400
          Re: try/except/finally Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-06-08 02:10 +0100
            Re: try/except/finally Roy Smith <roy@panix.com> - 2014-06-07 21:32 -0400
            Re: try/except/finally Marko Rauhamaa <marko@pacujo.net> - 2014-06-08 10:12 +0300
              Re: try/except/finally Joshua Landau <joshua@landau.ws> - 2014-06-08 18:57 +0100
              Re: try/except/finally Ian Kelly <ian.g.kelly@gmail.com> - 2014-06-08 12:07 -0600
              Re: try/except/finally Ian Kelly <ian.g.kelly@gmail.com> - 2014-06-08 12:02 -0600
        Re: try/except/finally Rustom Mody <rustompmody@gmail.com> - 2014-06-07 20:58 -0700
          Re: try/except/finally Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2014-06-10 09:27 +0200
            Re: try/except/finally Marko Rauhamaa <marko@pacujo.net> - 2014-06-10 12:07 +0300
            Re: try/except/finally Rustom Mody <rustompmody@gmail.com> - 2014-06-10 05:06 -0700
              Re: try/except/finally Skip Montanaro <skip@pobox.com> - 2014-06-10 13:11 -0500
                Re: try/except/finally Rustom Mody <rustompmody@gmail.com> - 2014-06-10 19:01 -0700
            Re: try/except/finally Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-06-10 19:14 +0100
              Re: try/except/finally Grant Edwards <invalid@invalid.invalid> - 2014-06-10 18:48 +0000
                Re: try/except/finally Chris Angelico <rosuav@gmail.com> - 2014-06-11 06:37 +1000
                Re: try/except/finally Roy Smith <roy@panix.com> - 2014-06-10 16:38 -0400
                Re: try/except/finally Chris Angelico <rosuav@gmail.com> - 2014-06-11 06:43 +1000
                Re: try/except/finally Ethan Furman <ethan@stoneleaf.us> - 2014-06-10 13:43 -0700
                Re: try/except/finally Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-06-10 22:59 +0100
                Re: try/except/finally Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-06-11 00:00 +0000
                Re: try/except/finally Chris Angelico <rosuav@gmail.com> - 2014-06-11 10:12 +1000
                Re: try/except/finally Roy Smith <roy@panix.com> - 2014-06-10 20:22 -0400
                Re: try/except/finally Tim Delaney <timothy.c.delaney@gmail.com> - 2014-06-11 10:40 +1000
                Re: try/except/finally Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-06-11 01:53 +0100
                Re: try/except/finally Chris Angelico <rosuav@gmail.com> - 2014-06-11 11:00 +1000
                Re: try/except/finally Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-06-11 02:06 +0100
                Re: try/except/finally alister <alister.nospam.ware@ntlworld.com> - 2014-06-11 08:35 +0000
                Re: try/except/finally Roy Smith <roy@panix.com> - 2014-06-11 08:50 -0400
              Re: try/except/finally alister <alister.nospam.ware@ntlworld.com> - 2014-06-10 19:02 +0000
    Re: try/except/finally Joshua Landau <joshua@landau.ws> - 2014-06-08 19:05 +0100
  Re:try/except/finally Dave Angel <davea@davea.name> - 2014-06-07 21:59 -0500
    Re: try/except/finally Philip Shaw <jnufcvyvuc@tznvy.pbz> - 2014-06-09 09:13 +0000
      Re: try/except/finally Marko Rauhamaa <marko@pacujo.net> - 2014-06-09 12:40 +0300
        Re: try/except/finally Shiyao Ma <i@introo.me> - 2014-06-10 00:23 +0800
        Re: try/except/finally Skip Montanaro <skip@pobox.com> - 2014-06-09 11:56 -0500

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