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
   7 ;; This file is part of GNU Emacs.
   8
   9 ;; GNU Emacs is free software; you can redistribute it and/or modify
  10 ;; it under the terms of the GNU General Public License as published by
  11 ;; the Free Software Foundation; either version 2, or (at your option)
  12 ;; any later version.
  13
  14 ;; GNU Emacs is distributed in the hope that it will be useful,
  15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 ;; GNU General Public License for more details.
  18
  19 ;; You should have received a copy of the GNU General Public License
  20 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  21 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  22 ;; Boston, MA 02111-1307, USA.
  23
  24 ;;; Code:
  25
  26 (defvar morse-code '(("a" . ".-")
  27                      ("b" . "-...")
  28                      ("c" . "-.-.")
  29                      ("d" . "-..")
  30                      ("e" . ".")
  31                      ("f" . "..-.")
  32                      ("g" . "--.")
  33                      ("h" . "....")
  34                      ("i" . "..")
  35                      ("j" . ".---")
  36                      ("k" . "-.-")
  37                      ("l" . ".-..")
  38                      ("m" . "--")
  39                      ("n" . "-.")
  40                      ("o" . "---")
  41                      ("p" . ".--.")
  42                      ("q" . "--.-")
  43                      ("r" . ".-.")
  44                      ("s" . "...")
  45                      ("t" . "-")
  46                      ("u" . "..-")
  47                      ("v" . "...-")
  48                      ("w" . ".--")
  49                      ("x" . "-..-")
  50                      ("y" . "-.--")
  51                      ("z" . "--..")
  52                      ;; Punctuation
  53                      ("=" . "-...-")
  54                      ("?" . "..--..")
  55                      ("/" . "-..-.")
  56                      ("," . "--..--")
  57                      ("." . ".-.-.-")
  58                      (":" . "---...")
  59                      ("'" . ".----.")
  60                      ("-" . "-....-")
  61                      ("(" . "-.--.-")
  62                      (")" . "-.--.-")
  63                      ;; Numbers
  64                      ("0" . "-----")
  65                      ("1" . ".----")
  66                      ("2" . "..---")
  67                      ("3" . "...--")
  68                      ("4" . "....-")
  69                      ("5" . ".....")
  70                      ("6" . "-....")
  71                      ("7" . "--...")
  72                      ("8" . "---..")
  73                      ("9" . "----."))
  74   "Morse code character set.")
  75
  76 (defun morse-region (beg end)
  77   "Convert all text in a given region to morse code."
  78   (interactive "r")
  79   (if (integerp end)
  80       (setq end (copy-marker end)))
  81   (save-excursion
  82     (let ((sep "")
  83           str morse)
  84       (goto-char beg)
  85       (while (< (point) end)
  86         (setq str (downcase (buffer-substring (point) (1+ (point)))))
  87         (cond ((looking-at "\\s-+")
  88                (goto-char (match-end 0))
  89                (setq sep ""))
  90               ((setq morse (assoc str morse-code))
  91                (delete-char 1)
  92                (insert sep (cdr morse))
  93                (setq sep "/"))
  94               (t
  95                (forward-char 1)
  96                (setq sep "")))))))
  97
  98 (defun unmorse-region (beg end)
  99   "Convert morse coded text in region to ordinary ASCII text."
 100   (interactive "r")
 101   (if (integerp end)
 102       (setq end (copy-marker end)))
 103   (save-excursion
 104     (let (str paren morse)
 105       (goto-char beg)
 106       (while (< (point) end)
 107         (if (null (looking-at "[-.]+"))
 108             (forward-char 1)
 109           (setq str (buffer-substring (match-beginning 0) (match-end 0)))
 110           (if (null (setq morse (rassoc str morse-code)))
 111               (goto-char (match-end 0))
 112             (replace-match
 113                   (if (string-equal "(" (car morse))
 114                       (if (setq paren (null paren)) "(" ")")
 115                     (car morse)) t)
 116             (if (looking-at "/")
 117                 (delete-char 1))))))))
 118
 119 (provide 'morse)
 120
 121 ;;; morse.el ends here