Re: Python language hack for C-style programmers [DO NOT USE!] :-)

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Date	Fri, 28 Mar 2014 03:12:25 +1100
Subject	Re: Python language hack for C-style programmers [DO NOT USE!] :-)
From	Chris Angelico <rosuav@gmail.com>
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On Fri, Mar 28, 2014 at 3:08 AM, Tim Chase
<python.list@tim.thechases.com> wrote:
> So when I stumbled upon this horrific atrocity of language abuse and
> scope leakage, I thought I'd share it.
>
>   if [m for m in [regex.match(some_string)] if m]:
>     do_something(m)
>
> And presto, assignment in an if-statement.

And presto, it doesn't work in Python 3:

>>> if [m for m in [5] if m]:
    print(m)

Traceback (most recent call last):
  File "<pyshell#2>", line 2, in <module>
    print(m)
NameError: name 'm' is not defined

So definitely don't do it. :)

ChrisA

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Re: Python language hack for C-style programmers [DO NOT USE!] :-) Chris Angelico <rosuav@gmail.com> - 2014-03-28 03:12 +1100

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