Re: Highlighting cursor for char before

[Eli Zaretskii <eliz@gnu.org>]

> From: Alexandre Garreau <galex-713@galex-713.eu>
> Date: Mon, 18 Oct 2021 14:36:30 +0200
> 
> TL;DR:  I know we can make the cursor so thin it becomes a bar like in 
> other apps, instead of highlighted following char… but how to make it 
> highlight the *previous* char? is there a way? that would be more logical 
> and less confusing, especially when switching between ltr and rtl

Your assumptions and some facts are not entirely correct.

First, the default block cursor is displayed correctly both in LTR and
RTL context in Emacs.  I'm not aware of any problems there.

Next, which character will be erased by DEL is indeed
context-dependent, but experienced readers of bidirectional scripts
have no trouble knowing which one almost instinctively.

Most importantly, it is entirely non-trivial to determine which is the
"character before", in bidirectional text.  Look at the code of
move-point-visually to see how non-trivial it is to solve a similar,
but different problem: which character is the one to the right or to
the left of the current one.  So if someone wants to submit patches to
support such "before" cursor, I'm sure such patches will be welcome,
but it's a significant job to come up with something like that, IMO.