Re: bidi-display-reordering is now non-nil by default

[Mohsen BANAN]

>>>>> On Sun, 31 Jul 2011 18:44:03 +0300, Eli Zaretskii <address@hidden> said:

  >> From: David Kastrup <address@hidden>
  >> Date: Sun, 31 Jul 2011 16:26:12 +0200

  David> I consider that approach a non-starter.  Or rather a non-finisher.

  Eli> Look, you only learned about this issue this morning.  I don't think
  Eli> it's wise to make up our minds about the best solution after so little
  Eli> thought.  I think we need more data points and more rational
  Eli> discussions of the various aspects of this.  I would also like to hear
  Eli> at least one other serious user of R2L scripts.  This is an important
  Eli> usability issue, it shouldn't be decided on a knee-jerk basis.

I agree. 

This is a good point to spend some time and
formulate some goals, policies and strategies.

I consider myself a serious user of R2L scripts
(Persian/Farsi). And here is my $0.02.

With bidi-display-reordering now set to non-nil by
default, a new chapter has been opened.

The previous chapter was adding bidi to emacs as
an editor.

The current chapter is that of adding bidi to
emacs as a User Environment (even broader than a
desktop environment).

That will likely involve modifications to many
emacs packages.

Prior to going towards the discussion of what are
the better ways of doing that, I think it is a
good idea to ask the question of: 

  When emacs24 is released and we say "emacs24 has bidi",
  
What does that mean?

Would support for R2L scripts in emacs24 be same as
L2R, in every respect and every where?

Or would emacs24 just support R2L in its core as
an editor? -- no goal of having any packages being
bidi-aware.

Of course, there is plenty of room between those
two extremes. In which case, there is the question
of: which packages?

As an R2L scripts user, my hope is for emacs24 at
a minimum to have:

  A- All emacs24 foundational packages be bidi-aware:
     dired, buffers lists, ...

  B- One usable set of basic personal communication/organization tools:
     Gnus, bbdb, calendar, org

As far as I can tell, making an emacs package
bidi-aware involves 2 things:

  1) Explicit over writing of paragraph direction
     where needed

  2) Custom formating because of bidi

For (2), here is an example of bidi in subject
line messing up the summary lines of Gnus.

---- Gnus Summary Sample Begin ----
:!   2 moons in the sky , August the 27th, يک آسمان و دو ماه|  37 |First LAST   
        |Jul 13 '10 
:!   Fw: بسیار جالب و خواندنی است ... فقط با دقت و حوصله بخو| 284 |First LAST   
        |14:15 
:!   Re: Next Saturday instead of this weekend              |  36 |First LAST   
        |14:22 
---- Gnus Summary Sample Ends  ----

The line number column for first message
[English+Farsi] (37) is out of place.

The line number column for second message
[Farsi] (284) is out of place.

For (1) paragraph direction detection, there may
be things that can be done in the core to improve
auto direction detection.

Making all of this happen is likely not going to
be easy because most (if not all) emacs package
developers are non-bidi-readers who likely don't
need or care about bidi.

So, I think we need to look for more serious bidi
users and pair them up with well selected package
owners.

For example, if Lars wanted to make the Gnus
Summary bidi-aware, I am there.

Your thoughts?

...Mohsen

...محسن