bug#23097: 24.5; ispell.el: lines with both CASECHARS and NOT-CASECHARS get sent to the spell checker

[Stefan Kangas]

Nikolay Kudryavtsev <nikolay.kudryavtsev@gmail.com> writes:

> This is not an external software bug, but very much an Emacs bug.
>
> I'm not sure what was the initial design idea for CASECHARS and
> NOT-CASECHARS, but whatever it was, it would not work effectively due to
> feeding the entire line. The most obvious practical use for them(being
> able to spellcheck languages with completely different alphabets without
> the spellchecker misfiring on either pass) would not work either.
>
> The ideal pratical fix for this should spellcheck such lines word by word.

Okay, but that's not a documented use-case, so I'm not sure that it's a
bug.  The thing you suggest may be possible, but would require
developing a new feature, for example to run two instances of the same
spell checker at once.

AFAIU, the best solution is to use an external spell checker that has
support for using two languages at once.  Why not use that?

Best regards,
Stefan Kangas