lisp/play/morse.el

   1 ;;; morse.el --- convert text to morse code and back
   2
   3 ;; Copyright (C) 1995 Free Software Foundation, Inc.
   4
   5 ;; Author: Rick Farnbach <rick_farnbach@MENTORG.COM>
   6 ;; Keywords: games
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software; you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation; either version 2, or (at your option)
  13 ;; any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  22 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  23 ;; Boston, MA 02111-1307, USA.
  24
  25 ;;; Commentary:
  26
  27 ;; Converts text to Morse code and back with M-x morese-region and
  28 ;; M-x unmorse-region (though Morse code is no longer official :-().
  29
  30 ;;; Code:
  31
  32 (defvar morse-code '(("a" . ".-")
  33                      ("b" . "-...")
  34                      ("c" . "-.-.")
  35                      ("d" . "-..")
  36                      ("e" . ".")
  37                      ("f" . "..-.")
  38                      ("g" . "--.")
  39                      ("h" . "....")
  40                      ("i" . "..")
  41                      ("j" . ".---")
  42                      ("k" . "-.-")
  43                      ("l" . ".-..")
  44                      ("m" . "--")
  45                      ("n" . "-.")
  46                      ("o" . "---")
  47                      ("p" . ".--.")
  48                      ("q" . "--.-")
  49                      ("r" . ".-.")
  50                      ("s" . "...")
  51                      ("t" . "-")
  52                      ("u" . "..-")
  53                      ("v" . "...-")
  54                      ("w" . ".--")
  55                      ("x" . "-..-")
  56                      ("y" . "-.--")
  57                      ("z" . "--..")
  58                      ;; Punctuation
  59                      ("=" . "-...-")
  60                      ("?" . "..--..")
  61                      ("/" . "-..-.")
  62                      ("," . "--..--")
  63                      ("." . ".-.-.-")
  64                      (":" . "---...")
  65                      ("'" . ".----.")
  66                      ("-" . "-....-")
  67                      ("(" . "-.--.-")
  68                      (")" . "-.--.-")
  69                      ;; Numbers
  70                      ("0" . "-----")
  71                      ("1" . ".----")
  72                      ("2" . "..---")
  73                      ("3" . "...--")
  74                      ("4" . "....-")
  75                      ("5" . ".....")
  76                      ("6" . "-....")
  77                      ("7" . "--...")
  78                      ("8" . "---..")
  79                      ("9" . "----."))
  80   "Morse code character set.")
  81
  82 ;;;###autoload
  83 (defun morse-region (beg end)
  84   "Convert all text in a given region to morse code."
  85   (interactive "r")
  86   (if (integerp end)
  87       (setq end (copy-marker end)))
  88   (save-excursion
  89     (let ((sep "")
  90           str morse)
  91       (goto-char beg)
  92       (while (< (point) end)
  93         (setq str (downcase (buffer-substring (point) (1+ (point)))))
  94         (cond ((looking-at "\\s-+")
  95                (goto-char (match-end 0))
  96                (setq sep ""))
  97               ((setq morse (assoc str morse-code))
  98                (delete-char 1)
  99                (insert sep (cdr morse))
 100                (setq sep "/"))
 101               (t
 102                (forward-char 1)
 103                (setq sep "")))))))
 104
 105 ;;;###autoload
 106 (defun unmorse-region (beg end)
 107   "Convert morse coded text in region to ordinary ASCII text."
 108   (interactive "r")
 109   (if (integerp end)
 110       (setq end (copy-marker end)))
 111   (save-excursion
 112     (let (str paren morse)
 113       (goto-char beg)
 114       (while (< (point) end)
 115         (if (null (looking-at "[-.]+"))
 116             (forward-char 1)
 117           (setq str (buffer-substring (match-beginning 0) (match-end 0)))
 118           (if (null (setq morse (rassoc str morse-code)))
 119               (goto-char (match-end 0))
 120             (replace-match
 121                   (if (string-equal "(" (car morse))
 122                       (if (setq paren (null paren)) "(" ")")
 123                     (car morse)) t)
 124             (if (looking-at "/")
 125                 (delete-char 1))))))))
 126
 127 (provide 'morse)
 128
 129 ;;; morse.el ends here