[Python-Dev] conditional expressions - add parens?

Alex Martelli aleaxit at gmail.com
Tue Mar 7 16:42:29 CET 2006


On Mar 7, 2006, at 7:29 AM, Steve Holden wrote:
    ...
>> In fact, I think the below examples are reasonable uses
>> that do a better job of expressing intent than the if
>> statement would.  I just don't like the mental backtrack
>> they require, and would like some sort of advance
>> warning.  Parentheses at least tell me "You're not done
>> yet; keep reading."
>>
>>>>> ack(r,r) if r not in cache
>>
>>>>> log(message) if error_flag
>>
> I think you've misunderstood the nature of the change. HTe new
> conditionals are *expressions*, they aren't postfix conditionals for
> statements.

Right, but the only effect of that on the examples is that they both  
need an 'else None' continuation or thereabouts.

I also predict widespread over-use of the new toy and agree with Jim  
that mandatory parentheses around the whole (X if Y else Z) construct  
would ameliorate legibility a bit.


Alex



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