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Re: Ifs and assignments

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Date Fri, 3 Jan 2014 11:07:58 +1100
Subject Re: Ifs and assignments
From Chris Angelico <rosuav@gmail.com>
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On Fri, Jan 3, 2014 at 11:06 AM, Chris Angelico <rosuav@gmail.com> wrote:
> Pass any object through truth() and it'll either stay the same (if
> it's true) or become this object (if it's false). You can then carry
> on with other method calls, and they'll all happily return false.
>
> result = (
>     truth(re1.match(string)).group(0) or
>     truth(re2.match(string)).group(0) or
>     truth(re3.match(string)).group(0) or
>     default_value
> )

Oh, just thought of a possible snag. Since an empty string comes up as
false, this exact notation would fail if the re can match nothing. But
you probably know if it's possible for that to happen, so don't use
this simple short-hand. :)

ChrisA

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Thread

Re: Ifs and assignments John Allsup <pydev@allsup.co> - 2014-01-02 21:44 +0000
  Re: Ifs and assignments Roy Smith <roy@panix.com> - 2014-01-02 18:36 -0500
    Re: Ifs and assignments Chris Angelico <rosuav@gmail.com> - 2014-01-03 11:07 +1100
    Re: Ifs and assignments Chris Angelico <rosuav@gmail.com> - 2014-01-03 11:06 +1100
    Re: Ifs and assignments Ethan Furman <ethan@stoneleaf.us> - 2014-01-02 20:16 -0800
    Re: Ifs and assignments Chris Angelico <rosuav@gmail.com> - 2014-01-03 16:35 +1100

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