[Python-ideas] SyntaxWarning for for/while/else without break or return?

[Georg Brandl]

Stephen J. Turnbull schrieb:
> geremy condra writes:
> 
>  > I grant you that compilers *shouldn't* be smarter than programmers,
>  > but I highly doubt that any program including an extraneous else
>  > clause is "working according to specifications", and that's the point
>  > of this proposal.
> 
> Actually, I can imagine someone developing a style where a redundant
> else was used to indicate "this is part of/cleanup of the for loop,
> and should go with it in any refactoring".
> 
> Say, in a program that speaks SMTP:
> 
>     for line in line_factory:
>         smtp_send(line + "\n")
>     else:
>         smtp_send(".\n")

Usually, that effect can be created by newlines:

    for line in line_factory:
        smtp_send(line + "\n")
    smtp_send(".\n")

    more code goes here

I'm not sure myself whether I like generating warnings for valid syntax,
but in the often-misunderstood case of for/else, I think it would be
reasonable.

Georg