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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