[code-quality] pylint: Else clause on a loop without break statement

[Kay Hayen]

Hello,

thanks for all the replies.

Of course I am aware that my use of the "else:" is different from the
"break" case
when it comes to "return". For return, the "else:" is not needed, as it
won't continue
the execution.

>     def _areConstants(expressions):
> >         for expression in expressions:
> >             if not expression.isExpressionConstantRef():
> >                 break
> >             if expression.isMutable():
> >                 break
> >         else:
> >             return True
> >         return False
>
> That's not an improvement but also not the obvious way to rewrite the
> code to suppress the, IMHO legitimate, warning.  Instead of introducing
> ``break``\s for an unnecessary ``else`` clause one could also just
> remove that unnecessary ``else``::
>

Mind you, I am using the "else:" specifically to express, that I expect the
loop
to return based on one element. I agree with you that the suggested code is
making that hard to discern and that removing the "else" clause is an
option.

The thing is, I developed a style, where a return in the loop always leads
to
a return in a else. It's the pick and choose method. So any time, I make
decisions based on an iterable, I do it like that.

def _areConstants(expressions):
>     for expression in expressions:
>         if not expression.isExpressionConstantRef():
>             return False
>         if expression.isMutable():
>             return False
>     return True
>
> Which improves the situation in a way, because now the fellow Python
> coder doesn't wonder where the ``break`` should be or if the author
> understood the semantics of ``else`` on loop constructs.
>

That precisely is the question. Is the "else" an emphasis, or is it an error
indicator. I can assure you that I did it on purpose. But if nobody gets
that,
it kinds of misses the point.

I take the general feedback to say "yes, using else: without need is a style
problem". So I will try and give it up. :-)


> I would also avoid this question by using `all()` here.  :-)
>

I learned of "any" and "all" relatively late. I agree for booleans it's the
better
choice, but it's another subject. Many times, it's not a boolean return
value.

Yours,
Kay
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