--- /dev/null
+;;; mule-caesar.el --- ROT 13-47 Caesar rotation utility
+
+;; Copyright (C) 1997,1998 Free Software Foundation, Inc.
+
+;; Author: MORIOKA Tomohiko <morioka@jaist.ac.jp>
+;; Keywords: ROT 13-47, caesar, mail, news, text/x-rot13-47
+
+;; This file is part of APEL (A Portable Emacs Library).
+
+;; This program is free software; you can redistribute it and/or
+;; modify it under the terms of the GNU General Public License as
+;; published by the Free Software Foundation; either version 2, or (at
+;; your option) any later version.
+
+;; This program is distributed in the hope that it will be useful, but
+;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+;; General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs; see the file COPYING. If not, write to the
+;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
+
+;;; Code:
+
+(defun mule-caesar-region (start end &optional stride-ascii)
+ "Caesar rotation of current region.
+Optional argument STRIDE-ASCII is rotation-size for Latin alphabet
+\(A-Z and a-z). For non-ASCII text, ROT-N/2 will be performed in any
+case (N=charset-chars; 94 for 94 or 94x94 graphic character set; 96
+for 96 or 96x96 graphic character set)."
+ (interactive "r\nP")
+ (setq stride-ascii (if stride-ascii
+ (mod stride-ascii 26)
+ 13))
+ (save-excursion
+ (save-restriction
+ (narrow-to-region start end)
+ (goto-char start)
+ (while (< (point)(point-max))
+ (let* ((chr (char-after (point))))
+ (cond ((and (<= ?A chr) (<= chr ?Z))
+ (setq chr (+ chr stride-ascii))
+ (if (> chr ?Z)
+ (setq chr (- chr 26))
+ )
+ (delete-char 1)
+ (insert chr)
+ )
+ ((and (<= ?a chr) (<= chr ?z))
+ (setq chr (+ chr stride-ascii))
+ (if (> chr ?z)
+ (setq chr (- chr 26))
+ )
+ (delete-char 1)
+ (insert chr)
+ )
+ ((<= chr ?\x9f)
+ (forward-char)
+ )
+ (t
+ (let* ((stride (lsh (charset-chars (char-charset chr)) -1))
+ (ret (mapcar (function
+ (lambda (octet)
+ (if (< octet 80)
+ (+ octet stride)
+ (- octet stride)
+ )))
+ (cdr (split-char chr)))))
+ (delete-char 1)
+ (insert (make-char (char-charset chr)
+ (car ret)(car (cdr ret))))
+ )))
+ )))))
+
+
+(require 'product)
+(product-provide (provide 'mule-caesar) (require 'apel-ver))
+
+;;; mule-caesar.el ends here