Re: Issues with japanese support

Hi, Ralf.  Thank you for your comment.

I found another problem in the fill code in
LaTeX-fill-move-to-break-point.
------ [A] ----------------------------------------------------------
(defun LaTeX-fill-move-to-break-point (linebeg)
  "Move to the position where the line should be broken."
  ;; COMPATIBILITY for Emacs < 22.1 and XEmacs
  (if (fboundp 'fill-move-to-break-point)
      (fill-move-to-break-point linebeg)
    ;; Cancel `forward-char' which is called just before
    ;; `LaTeX-fill-move-to-break-point' if the char before point matches
    ;; `LaTeX-nospace-between-char-regexp'.
    (if (and (featurep 'mule)
	     (TeX-looking-at-backward LaTeX-nospace-between-char-regexp))
	(backward-char 1)
      (skip-chars-backward "^ \n"))
----------------------------------------------------------------------
Here, the function TeX-looking-at-backward is called without a search
limit specified.  So, in a buffer without CJK letters, the search of
re-search-backward in that function is performed all the way back to the
beginning of the buffer (or the narrowing region) every time
LaTeX-fill-move-to-break-point is called in the filling loop (unless
used with CVS Emacs, which has fill-move-to-break-point).

So the relavant portion of the above [A] should be:
----- [B] ------------------------------------------------------------
    (if (and (featurep 'mule)
	     (TeX-looking-at-backward LaTeX-nospace-between-char-regexp 1))
	(backward-char 1)
      (skip-chars-backward "^ \n"))
----------------------------------------------------------------------

Here are other plans.  I think the same result will be achieved by the
following:
----- [C] ------------------------------------------------------------
    (unless (and (featurep 'mule)
		 (re-search-backward LaTeX-nospace-between-char-regexp
				     (1- (point)) t))
      (skip-chars-backward "^ \n"))
----------------------------------------------------------------------
I expect [C] will work faster than [B]. (However, I didn't actually
test.)  The drawback is that [C] might be less easy to read.

If we consider avoiding the use of regular expressions because of its
slowness, the following approach is possible:
----- [D] ------------------------------------------------------------
    (cond
     ((featurep 'xemacs)
      (unless (and (featurep 'mule)
		   (re-search-backward LaTeX-nospace-between-char-regexp
				       (1- (point)) t))
	(skip-chars-backward "^ \n")))
     (t ;; FSF Emacs 21
      (if (aref (char-category-set (char-before)) ?|)
	  (backward-char 1)
	(skip-chars-backward "^ \n"))))
----------------------------------------------------------------------
I'm not sure this is faster than [C] with Emacs 21 since the whole
structure grows up and the regular expression search in [C] is conducted
over only one character.  However, [D] has a good side effect that FSF
Emacs no more uses the variable LaTeX-nospace-between-char-regexp
throughout latex.el, so we can omit the defcustom declaration of this
variable with FSF Emacs.  This variable is already meaningless to CVS
Emacs, at least currently, and shows up in the customize menu as an
useless option now.  If we take approach [D], we can get rid of this
situation in CVS Emacs and Emacs 21 together.

Regards,
Ikumi Keita