Some fixes to follow coding conventions in files maintained by FSF.

[bpt/emacs.git] / lisp / rot13.el

diff --git a/lisp/rot13.el b/lisp/rot13.el
index 7c068bc..fcb349c 100644 (file)
--- a/lisp/rot13.el
+++ b/lisp/rot13.el
@@ -1,8 +1,8 @@
-;;; rot13.el --- display a buffer in rot13.
+;;; rot13.el --- display a buffer in rot13
 
 ;; Copyright (C) 1988 Free Software Foundation, Inc.
 
-;; Author: Howard Gayle:
+;; Author: Howard Gayle
 ;; Maintainer: FSF
 
 ;; This file is part of GNU Emacs.
@@ -18,18 +18,19 @@
 ;; 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, 675 Mass Ave, Cambridge, MA 02139, USA.
+;; 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.
 
-;; Commentary:
+;;; Commentary:
 
-;; The single entry point, `rot13-other-window', oerforms a Caesar cipher
+;; The single entry point, `rot13-other-window', performs a Caesar cipher
 ;; encrypt/decrypt on the current buffer and displays the result in another 
-;; window.  Rot13 encryption is sometimes used on USENET as a read-at-yur-
+;; window.  Rot13 encryption is sometimes used on USENET as a read-at-your-
 ;; own-risk wrapper for material some might consider offensive, such as
 ;; ethnic humor.
 ;;
-;; Written by Howard Gayle.  See case-table.el for details.
+;; Written by Howard Gayle.
 ;; This hack is mainly to show off the char table stuff.
 
 ;;; Code:
@@ -38,19 +39,35 @@
   (let ((table (make-display-table))
        (i 0))
     (while (< i 26)
-      (aset table (+ i ?a) (make-rope (+ (% (+ i 13) 26) ?a)))
-      (aset table (+ i ?A) (make-rope (+ (% (+ i 13) 26) ?A)))
+      (aset table (+ i ?a) (vector (+ (% (+ i 13) 26) ?a)))
+      (aset table (+ i ?A) (vector (+ (% (+ i 13) 26) ?A)))
       (setq i (1+ i)))
     table)
   "Char table for rot 13 display.")
 
 ;;;###autoload
 (defun rot13-other-window ()
-  "Display current buffer in rot 13 in another window."
+  "Display current buffer in rot 13 in another window.
+The text itself is not modified, only the way it is displayed is affected.
+
+To terminate the rot13 display, delete that window.  As long as that window
+is not deleted, any buffer displayed in it will become instantly encoded
+in rot 13.
+
+See also `toggle-rot13-mode'."
   (interactive)
   (let ((w (display-buffer (current-buffer) t)))
     (set-window-display-table w rot13-display-table)))
 
+;;;###autoload
+(defun toggle-rot13-mode ()
+  "Toggle the use of rot 13 encoding for the current window."
+  (interactive)
+  (if (eq (window-display-table (selected-window)) rot13-display-table)
+      (set-window-display-table (selected-window) nil)
+    (if (null (window-display-table (selected-window)))
+       (set-window-display-table (selected-window) rot13-display-table))))
+
 (provide 'rot13)
 
 ;;; rot13.el ends here