;; Copyright (C) 1997 Free Software Foundation, Inc.
;; Author: MORIOKA Tomohiko <morioka@jaist.ac.jp>
-;; Version: $Id: mule-caesar.el,v 1.2 1997-05-09 01:36:41 morioka Exp $
+;; Version: $Id: mule-caesar.el,v 1.3 1997-05-09 02:47:55 morioka Exp $
;; Keywords: ROT 13-47, caesar, mail, news, text/x-rot13-47
;; This file is part of APEL (A Portable Emacs Library).
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.
-;;; Commentary:
-
-;; Thanks for Martin Buchholz <mrb@eng.sun.com>'s suggestion
-
;;; Code:
-(defun mule-caesar-string (string &optional stride-ascii)
- "Caesar rotation of STRING, and return the result.
-Optional argument STRIDE-ASCII is rotation-size for Latin alphabet
-\(A-Z and a-z). For non-ASCII text, ROT47 will be performed in any
-case."
- (setq stride-ascii
- (if stride-ascii
- (mod stride-ascii 26)
- 13))
- (mapconcat (function
- (lambda (chr)
- (if (< chr 128)
- (cond ((and (<= ?A chr) (<= chr ?Z))
- (setq chr (+ chr stride-ascii))
- (if (> chr ?Z)
- (setq chr (- chr 26))
- ))
- ((and (<= ?a chr) (<= chr ?z))
- (setq chr (+ chr stride-ascii))
- (if (> chr ?z)
- (setq chr (- chr 26))
- )))
- (let ((octet (logand chr 127)))
- (if (and (< 32 octet) (< octet 127))
- (setq chr
- (if (< octet 80)
- (+ chr 47)
- (- chr 47)))
- )))
- (char-to-string chr)
- )) string "")
- )
+(defun char-to-octet-list (character)
+ "Return list of octets in code table of graphic character set."
+ (let* ((code (char-int character))
+ (dim (charset-dimension (char-charset code)))
+ dest)
+ (while (> dim 0)
+ (setq dest (cons (logand code 127) dest)
+ dim (1- dim)
+ code (lsh code -7))
+ )
+ dest))
(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, ROT47 will be performed in any
-case."
+\(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
- (let ((str (buffer-substring start end)))
- (delete-region start end)
- (insert (mule-caesar-string str stride-ascii))
- )))
-
+ (save-restriction
+ (narrow-to-region start end)
+ (goto-char start)
+ (while (< (point)(point-max))
+ (let* ((chr (char-after (point)))
+ (charset (char-charset chr))
+ )
+ (if (eq charset 'ascii)
+ (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)
+ )
+ (t
+ (forward-char)
+ ))
+ (let* ((stride (lsh (charset-chars charset) -1))
+ (ret (mapcar (function
+ (lambda (octet)
+ (if (< octet 80)
+ (+ octet stride)
+ (- octet stride)
+ )))
+ (char-to-octet-list chr))))
+ (delete-char 1)
+ (insert (make-char (char-charset chr)
+ (car ret)(car (cdr ret))))
+ )))))))
+
(provide 'mule-caesar)