Re: Unicode confusables and reordering characters considered harmful, a simple solution

[Stefan Kangas]

Eli Zaretskii <eliz@gnu.org> writes:

>> In any case, the above leads me back to the simple idea to raise
>> byte-compiler (or even `read'?) warnings for the problematic control
>> characters unless a specific variable is set to t, or unless the piece
>> of code using them is wrapped in some `with-suppressed-warnings' call.
>
> That would flag our own code, because we sometimes wrap strings in
> these directional format control characters, to avoid confusing
> display.  Those are exactly the valid uses of these characters, ones
> against which it makes no sense to issue a warning.

We would need to mark those uses as okay, of course.

>> Or we do it the other way around: users mark a source code file to say
>> that "this file will never contain RTL characters" (but RTL scripts in
>> ELisp code is pretty uncommon, I think).
>
> So now everyone is suspect unless certified otherwise?  How does this
> make sense?

The idea is to make the programmer explicitly say yes to using these
characters.  (Or at the very least give them a way to say no, but I'd
much prefer the former.)