Re: Feature suggestion -- return if true

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From	Grant Edwards <invalid@invalid.invalid>
Newsgroups	comp.lang.python
Subject	Re: Feature suggestion -- return if true
Date	Tue, 12 Apr 2011 13:50:23 +0000 (UTC)
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On 2011-04-12, James Mills <prologic@shortcircuit.net.au> wrote:
> On Tue, Apr 12, 2011 at 4:08 PM, Nobody <nobody@nowhere.com> wrote:
>> It should be abundantly clear that this only returns if the expression is
>> considered true, otherwise it continues on to the following statements.
>
> Uggh come on guys. We've been over this.
> You cannot make that assumption.

You most certain can.  Try it yourself in an interpreter.  The
OP's code snippit will not return if expr is false, rather it will
continue executing in the current context:

>>> def foo(expr):
...   __temp__ = expr                         # these two lines are
...   if __temp__:  return __temp__           # the OP's code snippet
...   print "the code snippet did not return"
... 
>>> print foo(9)
9
>>> 
>>> print foo(0)
the code snippet did not return
None
>>> 

-- 
Grant Edwards               grant.b.edwards        Yow! One FISHWICH coming
                                  at               up!!
                              gmail.com

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Feature suggestion -- return if true zildjohn01 <zildjohn01@gmail.com> - 2011-04-11 16:17 -0700
  Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 10:27 +1000
    Re: Feature suggestion -- return if true Grant Edwards <invalid@invalid.invalid> - 2011-04-12 01:44 +0000
      Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 12:12 +1000
        Re: Feature suggestion -- return if true Grant Edwards <invalid@invalid.invalid> - 2011-04-12 02:18 +0000
          Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 12:44 +1000
            Re: Feature suggestion -- return if true Grant Edwards <invalid@invalid.invalid> - 2011-04-12 13:42 +0000
            Re: Feature suggestion -- return if true "Martin v. Loewis" <martin@v.loewis.de> - 2011-04-17 12:03 +0200
              Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-18 09:36 +1000
      Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 12:20 +1000
      Re: Feature suggestion -- return if true Zero Piraeus <schesis@gmail.com> - 2011-04-11 22:43 -0400
      Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-12 12:44 +1000
      Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-12 12:49 +1000
      Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 12:59 +1000
      Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 13:01 +1000
        Re: Feature suggestion -- return if true Nobody <nobody@nowhere.com> - 2011-04-12 07:08 +0100
          Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 16:21 +1000
            Re: Feature suggestion -- return if true Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-04-12 10:52 +0000
            Re: Feature suggestion -- return if true scattered <tooscattered@gmail.com> - 2011-04-12 03:55 -0700
              Re: Feature suggestion -- return if true "Colin J. Williams" <cjw@ncf.ca> - 2011-04-12 10:01 -0400
            Re: Feature suggestion -- return if true Grant Edwards <invalid@invalid.invalid> - 2011-04-12 13:50 +0000
        Re: Feature suggestion -- return if true Grant Edwards <invalid@invalid.invalid> - 2011-04-12 13:44 +0000
      Re: Feature suggestion -- return if true Westley Martínez <anikom15@gmail.com> - 2011-04-12 07:05 -0700
        Re: Feature suggestion -- return if true scattered <tooscattered@gmail.com> - 2011-04-12 07:58 -0700
          Re: Feature suggestion -- return if true Westley Martínez <anikom15@gmail.com> - 2011-04-12 15:45 -0700
          Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-13 08:52 +1000
        Re: Feature suggestion -- return if true zildjohn01 <zildjohn01@gmail.com> - 2011-04-12 11:25 -0700
          Re: Feature suggestion -- return if true Terry Reedy <tjreedy@udel.edu> - 2011-04-12 15:14 -0400
          Re: Feature suggestion -- return if true alex23 <wuwei23@gmail.com> - 2011-04-12 21:05 -0700
    Re: Feature suggestion -- return if true Teemu Likonen <tlikonen@iki.fi> - 2011-04-12 21:00 +0300
      Re: Feature suggestion -- return if true Ian Kelly <ian.g.kelly@gmail.com> - 2011-04-12 12:25 -0600
        Re: Feature suggestion -- return if true Neil Cerutti <neilc@norwich.edu> - 2011-04-12 20:13 +0000
          Re: Feature suggestion -- return if true Neil Cerutti <neilc@norwich.edu> - 2011-04-12 20:16 +0000
      Re: Feature suggestion -- return if true Ian Kelly <ian.g.kelly@gmail.com> - 2011-04-12 12:29 -0600
      Re: Feature suggestion -- return if true Paul Rudin <paul.nospam@rudin.co.uk> - 2011-04-12 19:28 +0100
      Re: Feature suggestion -- return if true Chris Rebert <clp2@rebertia.com> - 2011-04-12 13:26 -0700
      Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-13 08:34 +1000
      Re: Feature suggestion -- return if true Ethan Furman <ethan@stoneleaf.us> - 2011-04-12 16:06 -0700
      Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-13 09:12 +1000
      Re: Feature suggestion -- return if true Westley Martínez <anikom15@gmail.com> - 2011-04-12 16:15 -0700
      Re: Feature suggestion -- return if true Ethan Furman <ethan@stoneleaf.us> - 2011-04-12 16:48 -0700
        Re: Feature suggestion -- return if true Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-04-13 00:03 +0000
          Re: Feature suggestion -- return if true Ethan Furman <ethan@stoneleaf.us> - 2011-04-12 19:42 -0700
          Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-13 13:00 +1000
          Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-13 13:28 +1000
      Re: Feature suggestion -- return if true Teemu Likonen <tlikonen@iki.fi> - 2011-04-13 13:58 +0300
  Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-12 10:46 +1000
    Re: Feature suggestion -- return if true Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2011-04-17 16:21 +1200
      Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-17 14:31 +1000
      Re: Feature suggestion -- return if true Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-04-17 08:45 +0000
        Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-17 19:07 +1000
          Re: Feature suggestion -- return if true Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-04-17 15:23 +0000
        Re: Feature suggestion -- return if true Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2011-04-18 12:25 +1200
        Re: Feature suggestion -- return if true Dave Angel <davea@ieee.org> - 2011-04-17 22:04 -0400
        Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-18 12:10 +1000
          Re: Feature suggestion -- return if true Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2011-04-19 12:35 +1200
            Re: Feature suggestion -- return if true Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2011-04-19 09:42 +0300
              Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-19 17:01 +1000
      Re: Feature suggestion -- return if true "D'Arcy J.M. Cain" <darcy@druid.net> - 2011-04-17 08:33 -0400
        Re: Feature suggestion -- return if true Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-04-17 15:10 +0000
        Re: Feature suggestion -- return if true aahz@pythoncraft.com (Aahz) - 2011-04-18 09:11 -0700
      Re: Feature suggestion -- return if true Greg Ewing <greg.ewing@canterbury.ac.nz> - 2011-04-18 11:09 +1200
  Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-12 10:51 +1000
  Re: Feature suggestion -- return if true Paul Rubin <no.email@nospam.invalid> - 2011-04-11 23:58 -0700
    Re: Feature suggestion -- return if true John Roth <johnroth1@gmail.com> - 2011-04-12 06:16 -0700
    Re: Feature suggestion -- return if true Mel <mwilson@the-wire.com> - 2011-04-12 11:12 -0400

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