[Tutor] Readabilty vs 80 characters

[Prasad, Ramit]

>      I have a question about style. In PEP-8, it says don't exceed 79
> characters, but can this rule ever be trumped by
> readability?
> 
> Eg.
> 
> 
>      if someobject.filter(something) \
>           .filter(somethingreallyreallyreallyreallylong ==
> somethingelsereallyreallylong) \
>           .filter(othethingreallylongreallyreally ==
> ternarythingreallyreallyreallylong) \
>           .filter(thirdthingreallylessreallymaybelong ==
> thirdotherthingreallylong) \
>           .first():
>           < do something >
> 
>       if someobject.filter(something) \
>           .filter(somethingreallyreallyreallyreallylong == \
>                somethingelsereallyreallylong) \
>           .filter(othethingreallylongreallyreally == \
>               ternarythingreallyreallyreallylong ) \
>           .filter(thirdthingreallylessreallymaybelong == \
>                thirdotherthingreallylong) \
>           .first():
>           < do something >
> 
> 
> The first example is more readable to me but violates the 80 character
> rule. The second is less readable, but doesn't violate
> the 80 character rule.
> 
> Is there a guideline or convention that pythonistas follow about this
> style case?

It is a guideline, not a rule. Usually your (work) environment or 
common sense trumps the guideline.

On a side note, if you wrap that if statement with a parenthesis 
you can avoid the error prone '\' at the end of each line


       if ( someobject.filter(something) 
           .filter(somethingreallyreallyreallyreallylong == 
                somethingelsereallyreallylong) 
           .filter(othethingreallylongreallyreally == 
               ternarythingreallyreallyreallylong ) 
           .filter(thirdthingreallylessreallymaybelong == 
                thirdotherthingreallylong) 
           .first() ):
           < do something >



Ramit


Ramit Prasad | JPMorgan Chase Investment Bank | Currencies Technology
712 Main Street | Houston, TX 77002
work phone: 713 - 216 - 5423

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