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

[Chong Yidong]

Eli Zaretskii <address@hidden> writes:

>> Still, it seems better not to change Gnus to proactively insert LRM
>> characters, but leave it to those users who care to customize it as
>> necessary.
>
> I don't think this is a good idea.  It requires users to know too much
> about the reordering algorithm.  From this discussion you may conclude
> that those who need it will have that knowledge anyway, but I think
> this conclusion would be wrong: the participants of this discussion
> who argue for usage of these characters are not typical users.

OK, how about introducing a function similar to the following?

(defun string-mark-left-to-right (str)
  "Return a string based on STR that can be embedded in LTR text.
If STR ends in right-to-left (RTL) script, return a string
consisting of STR followed by a left-to-right mark (LRM)
character.  Otherwise, return STR."
  (if --??--this-string-needs-an-lrm--??--
      (concat str "\u200E")
    str))

(Can you tell us how to fill in the missing piece above?)

*** lisp/gnus/gnus-sum.el       2011-08-05 23:29:17 +0000
--- lisp/gnus/gnus-sum.el       2011-08-07 17:20:07 +0000
***************
*** 5357,5362 ****
--- 5357,5367 ----
                   gnus-summary-same-subject
                 subject))
              (t gnus-summary-same-subject)))
+ 
+           (if gnus-tmp-subject-or-nil
+               (setq gnus-tmp-subject-or-nil
+                     (string-mark-left-to-right gnus-tmp-subject-or-nil)))
+ 
            (if (and (eq gnus-summary-make-false-root 'adopt)
                     (= gnus-tmp-level 1)
                     (memq number gnus-tmp-gathered))