Bidi paragraph direction in terminal emulators

Eli Zaretskii via Unicode unicode at
Tue Feb 5 10:07:59 CST 2019

> From: Egmont Koblinger <egmont at>
> Date: Tue, 5 Feb 2019 02:28:50 +0100
> Cc: unicode at
> I have to admit, I'm not an Emacs user, I only have some vague ideas
> how powerful a tool it is. But in its very core I still believe it's a
> text editor – is it fair to say this? It could be used for example to
> conveniently create TUTORIAL.he.

It is a text editing/processing environment which has a lot of
text-based applications built on top of it.  It could (and was) used
to create TUTORIAL.he, but it can and is used for much more.

> There are plenty of line-oriented tools.
> [...]

Actually, for every utility you mention, Emacs has a command that
either invokes the utility and presents its output, or does the same
job by using built-in features.  So most/all of the jobs you mention
are routinely done in Emacs.  After all, Emacs is a programmer's
editor at its core, so every job programmers routinely do from the
shell prompt has an equivalent feature in Emacs.  You can even run
shells inside Emacs, with Emacs serving as a terminal emulator (which
then supports bidi ;-).

> There are just sooooooo many use cases, it's impossible to perfectly
> address all of them at once.

I don't think you need to look for a perfect solution.  You need to
look for one that works reasonably well in practice.  It is my
experience in Emacs that the empty line as paragraph delimiter
produces much better results than if you treat each line as a separate
paragraph.  We do have in Emacs features that allow to override the
default paragraph direction, but experience shows that they are used
relatively rarely.

> I'm confident that my specification which says that it should be
> preserved as a 100 character long paragraph and passed to BiDi
> accordingly is already a significant step forward.

I agree, but I urge you to make one more step, which IME is really

More information about the Unicode mailing list