1 ;;; mule-caesar.el --- ROT 13-47 Caesar rotation utility
3 ;; Copyright (C) 1997 Free Software Foundation, Inc.
5 ;; Author: MORIOKA Tomohiko <morioka@jaist.ac.jp>
6 ;; Version: $Id: mule-caesar.el,v 1.1 1997-05-09 01:22:58 morioka Exp $
7 ;; Keywords: ROT 13-47, caesar, mail, news, text/x-rot13-47
9 ;; This file is part of APEL (A Portable Emacs Library).
11 ;; This program is free software; you can redistribute it and/or
12 ;; modify it under the terms of the GNU General Public License as
13 ;; published by the Free Software Foundation; either version 2, or (at
14 ;; your option) any later version.
16 ;; This program is distributed in the hope that it will be useful, but
17 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 ;; General Public License for more details.
21 ;; You should have received a copy of the GNU General Public License
22 ;; along with GNU Emacs; see the file COPYING. If not, write to the
23 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
24 ;; Boston, MA 02111-1307, USA.
28 ;; Thanks for Martin Buchholz <mrb@eng.sun.com>'s suggestion
32 (defun mule-caesar-string (string &optional stride-ascii)
33 "Caesar rotation of STRING, and return the result.
34 Optional argument STRIDE-ASCII is rotation-size for Latin alphabet
35 \(A-Z and a-z). For non-ASCII text, ROT47 will be performed in any
44 (cond ((and (<= ?A chr) (<= chr ?Z))
45 (setq chr (+ chr stride-ascii))
49 ((and (<= ?a chr) (<= chr ?z))
50 (setq chr (+ chr stride-ascii))
54 (let ((octet (logand chr 127)))
55 (if (and (< 32 octet) (< octet 127))
65 (defun mule-caesar-region (start end stride-ascii)
66 "Caesar rotation of current region.
67 Optional argument STRIDE-ASCII is rotation-size for Latin alphabet
68 \(A-Z and a-z). For non-ASCII text, ROT47 will be performed in any
72 (let ((str (buffer-substring start end)))
73 (delete-region start end)
74 (insert (mule-caesar-string str stride-ascii))
78 (provide 'mule-caesar)
80 ;;; mule-caesar.el ends here