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Re: One liners

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From Terry Reedy <tjreedy@udel.edu>
Subject Re: One liners
Date Sat, 07 Dec 2013 16:02:26 -0500
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On 12/7/2013 11:13 AM, Rotwang wrote:
> On 07/12/2013 12:41, Jussi Piitulainen wrote:
>> [...]
>>
>>    if tracks is None:
>>       tracks = []
>
> Sorry to go off on a tangent, but in my code I often have stuff like
> this at the start of functions:
>
>      tracks = something if tracks is None else tracks
>
> or, in the case where I don't intend for the function to be passed
> non-default Falsey values:
>
>      tracks = tracks or something
>
> Is there any reason why the two-line version that avoids the ternary
> operator should be preferred to the above?

The 'extra' line is not necessary, as one can write

if tracks is None: tracks = [] # or something

I prefer this because it exactly expresses what one want done. The other 
branch

else: tracks = tracks

is superfluous and to me unaesthetic.

-- 
Terry Jan Reedy

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Thread

Re: One liners Michael Torrie <torriem@gmail.com> - 2013-12-06 17:20 -0700
  Re: One liners Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-07 02:28 +0000
    Re: One liners Chris Angelico <rosuav@gmail.com> - 2013-12-07 13:40 +1100
    Re: One liners Roy Smith <roy@panix.com> - 2013-12-06 22:27 -0500
      Re: One liners Chris Angelico <rosuav@gmail.com> - 2013-12-07 15:06 +1100
      Re: One liners Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-07 11:27 +0000
        Re: One liners Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2013-12-07 14:41 +0200
          Re: One liners Rotwang <sg552@hotmail.co.uk> - 2013-12-07 16:13 +0000
            Re: One liners Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-07 16:25 +0000
              Re: One liners Rotwang <sg552@hotmail.co.uk> - 2013-12-08 02:23 +0000
            Re: One liners Michael Torrie <torriem@gmail.com> - 2013-12-07 09:26 -0700
            Re: One liners Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2013-12-07 19:49 +0200
            Re: One liners Terry Reedy <tjreedy@udel.edu> - 2013-12-07 16:02 -0500
      Re: One liners Michael Torrie <torriem@gmail.com> - 2013-12-07 09:56 -0700
        Re: One liners rusi <rustompmody@gmail.com> - 2013-12-07 09:10 -0800
      Re: One liners Michael Torrie <torriem@gmail.com> - 2013-12-07 10:02 -0700

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