Re: Message Mode and bidi

[Eli Zaretskii <eliz@gnu.org>]

> From: Eric Abrahamsen <eric@ericabrahamsen.net>
> Date: Wed, 28 Feb 2024 08:54:54 -0800
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > But beware: doing this in Emacs will cause effects that are unpleasant
> > to readers of bidirectional text, because you could have "chess-like"
> > text display, like this:
> >
> > asasasasasasasasasasasasassa
> >                                                 ASASASASASASASASASASASASA
> > xcxcxcxcxcxcxcxcxcxcxcxcxc
> >                                                        JKJNJKKKNKNKNKNKNK
> >
> > etc.  Here upper-case letters stand for RTL (like Arabic or Farsi)
> > text and lower-case letters stand for LTR (like Latin or Cyrillic)
> > text.
> 
> This is the effect I was imagining in the header section of the message
> buffer, and why I thought we should probably skip trying to handle this.
> message-mode headers can be "continuation headers", as well, effectively
> line-wrapped, which would make it even harder.

Yes.  But the same can happen in the body of the message, and will IMO
be even more annoying, because people do care about the body.

> Thanks for the background! I guess I was hoping that we could at least
> support OP's original request, which is making the first paragraph of
> the message body independent of the mail header separator as regards
> BIDI display. I experimented with putting the value of
> `mail-header-separator' into `bidi-paragraph-start|separate-re', but
> couldn't get it to display that first paragraph starting on the right.
> Do you think this is feasible, and worth the effort?

No, I don't think it's worth the effort, even if you succeed.  The
price of leaving an empty line after the headers is so small that it
isn't worth the hassle to try to avoid it.  Once the user does that a
few times, the technique will be burned into his/her muscle memory (I
know because I went through that process myself, long ago).