for / while else doesn't make sense

[Steven D'Aprano]

On Sat, 21 May 2016 10:24 am, Jon Ribbens wrote:

> On 2016-05-20, Ethan Furman <ethan at stoneleaf.us> wrote:

>> If you don't take the extra step of _break_ it is the usual case.
> 
> Having an "for: else:" clause without a "break" would be so unusual
> that it's literally nonexistent, because it would always be a bug.
> So no, it isn't the usual case for "for: else:".


What do you mean? A for...else without a break is perfectly legal code, and
does *EXACTLY* what it is documented as doing:

- first the "for" block runs, looping as appropriate;
- THEN the "else" block runs, *once*.

How is this "always a bug"?

Would you classify the second line here:

print("Hello World!")
pass


as a bug? What exactly would your bug report be? "pass statement does
nothing, as expected. It should do nothing. Please fix."


>> But as others have said, this isn't going to change now, and I'm okay
>> with that.  But, please, be a bit more understanding of those who don't
>> immediately grok the for/else and while/else loops.
> 
> You're misunderstanding me. I'm not saying that the meaning of
> "for: else:" is 100% intuitively obvious. 

I should hope not, because as it stands with the horribly misleading
keyword "else" it is counter-intuitive and confusing. Which is a crying
shame, because it is a useful feature that actually does make a lot of
sense, if only the keyword were better!


> I'm saying that it's 
> *more* obvious than it would be if it used any of the other existing
> keywords. I suppose I'm also saying that there isn't any other
> obvious word that could be made into a keyword that would be better
> than "else" (even if we assumed that adding a new keyword was a
> cost-free exercise).

Well, that's a matter of opinion. And you know what they same about
opinions... there are always two, the foolish, pig-ignorant one, and mine.

:-)



-- 
Steven