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Date: Mon, 06 Jan 2014 09:51:28 +0200
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Subject: Re: Postfix conditionals
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On 06-01-2014 03:40, Rhodri James wrote:
> On Sun, 05 Jan 2014 20:24:53 -0000, Göktuğ Kayaalp <self@gkayaalp.com> 
> wrote:
>
>> AFAIK, we do not have "postfix conditionals" in Python, i.e. a 
>> condition appended to a statement, which determines whether the 
>> statement runs or not:
>
>>    py> for i in [False]:
>>    ...     break if not i
>
>>  The above piece of code is equivalent to this in Python:
>
>>    py> for i in [False]:
>>    ...    if not i
>>    ...        break
>
>> I believe that the first example is superior to the second example 
>> when the two is compared for readability and intuitiveness.
>
> In my past life as a newcomer to Perl, I thought this too. Postfix 
> conditionals read more like English, so they would be easier to take 
> in and understand.  As I wrote more code, I discovered that this 
> didn't seem to be the case; except in very simple cases, I had to 
> mentally transpose the conditional back to the start of the statement 
> to properly comprehend what was going on and what the results would be 
> for my sample data.
>
> It looks like a good idea, but I don't think it works that well in 
> practice.
>
Thanks for the input! I'd be quite interested in examples which required 
you to "mentally transpose the conditional back to the start of the 
statement", by the way.

         gk