code.delx.au - gnu-emacs/blob - leim/quail/uni-input.el

   1 ;;; uni-input.el --- Hex Unicode input method
   2
   3 ;; Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
   4 ;;   Free Software Foundation, Inc.
   5 ;; Copyright (C) 2004, 2005, 2006, 2007, 2008
   6 ;;   National Institute of Advanced Industrial Science and Technology (AIST)
   7 ;;   Registration Number H14PRO021
   8
   9 ;; Author: Dave Love <fx@gnu.org>
  10 ;; Keywords: i18n
  11
  12 ;; This file is part of GNU Emacs.
  13
  14 ;; This file is free software; you can redistribute it and/or modify
  15 ;; it under the terms of the GNU General Public License as published by
  16 ;; the Free Software Foundation; either version 3, or (at your option)
  17 ;; any later version.
  18
  19 ;; This file is distributed in the hope that it will be useful,
  20 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  21 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22 ;; GNU General Public License for more details.
  23
  24 ;; You should have received a copy of the GNU General Public License
  25 ;; along with GNU Emacs; see the file COPYING.  If not, write to
  26 ;; the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  27 ;; Boston, MA 02110-1301, USA.
  28
  29 ;;; Commentary:
  30
  31 ;; Provides an input method for entering characters by hex unicode in
  32 ;; the form `uxxxx', similarly to the Yudit editor.
  33
  34 ;; This is not really a Quail method, but uses some Quail functions.
  35 ;; There is probably A Better Way.
  36
  37 ;; You can get a similar effect by using C-q with
  38 ;; `read-quoted-char-radix' set to 16.
  39
  40 ;; Note that this only allows you to enter BMP values unless someone
  41 ;; extends it to use variable numbers of digits.
  42
  43 ;;; Code:
  44
  45 (require 'quail)
  46
  47 (defun ucs-input-insert-char (char)
  48   (insert char)
  49   (move-overlay quail-overlay (overlay-start quail-overlay) (point)))
  50
  51 (defun ucs-input-method (key)
  52   (if (or buffer-read-only
  53           (and (/= key ?U) (/= key ?u)))
  54       (list key)
  55     (quail-setup-overlays nil)
  56     (ucs-input-insert-char key)
  57     (let ((modified-p (buffer-modified-p))
  58           (buffer-undo-list t)
  59           (input-method-function nil)
  60           (echo-keystrokes 0)
  61           (help-char nil)
  62           (events (list key))
  63           (str "    "))
  64       (unwind-protect
  65           (catch 'non-digit
  66             (progn
  67               (dotimes (i 4)
  68                 (let ((seq (read-key-sequence nil))
  69                       key)
  70                   (if (and (stringp seq)
  71                            (= 1 (length seq))
  72                            (setq key (aref seq 0))
  73                            (memq key '(?0 ?1 ?2 ?3 ?4 ?5 ?6 ?7 ?8 ?9 ?a
  74                                           ?b ?c ?d ?e ?f ?A ?B ?C ?D ?E ?F)))
  75                       (progn
  76                         (push key events)
  77                         (ucs-input-insert-char key))
  78                     (quail-delete-region)
  79                     (throw 'non-digit (append (reverse events)
  80                                               (listify-key-sequence seq))))))
  81               (quail-delete-region)
  82               (let ((n (string-to-number (apply 'string
  83                                             (cdr (nreverse events)))
  84                                      16)))
  85                 (if (characterp n)
  86                     (list n)))))
  87         (quail-delete-overlays)
  88         (set-buffer-modified-p modified-p)
  89         (run-hooks 'input-method-after-insert-chunk-hook)))))
  90
  91 (defun ucs-input-activate (&optional arg)
  92   "Activate UCS input method.
  93 With arg, activate UCS input method if and only if arg is positive.
  94
  95 While this input method is active, the variable
  96 `input-method-function' is bound to the function `ucs-input-method'."
  97   (if (and arg
  98           (< (prefix-numeric-value arg) 0))
  99       (unwind-protect
 100           (progn
 101             (quail-hide-guidance)
 102             (quail-delete-overlays)
 103             (setq describe-current-input-method-function nil))
 104         (kill-local-variable 'input-method-function))
 105     (setq inactivate-current-input-method-function 'ucs-input-inactivate)
 106     (setq describe-current-input-method-function 'ucs-input-help)
 107     (quail-delete-overlays)
 108     (if (eq (selected-window) (minibuffer-window))
 109         (add-hook 'minibuffer-exit-hook 'quail-exit-from-minibuffer))
 110     (set (make-local-variable 'input-method-function)
 111          'ucs-input-method)))
 112
 113 (defun ucs-input-inactivate ()
 114   "Inactivate UCS input method."
 115   (interactive)
 116   (ucs-input-activate -1))
 117
 118 (defun ucs-input-help ()
 119   (interactive)
 120   (with-output-to-temp-buffer "*Help*"
 121     (princ "\
 122 Input method: ucs (mode line indicator:U+)
 123
 124 Input as Unicode: U<hex> or u<hex>, where <hex> is a four-digit hex number.")))
 125
 126 ;; The file ../leim-ext.el contains the following call.
 127 ;; (register-input-method "ucs" "UTF-8" 'ucs-input-activate "U+"
 128 ;;                     "Unicode input as hex in the form Uxxxx.")
 129
 130 (provide 'uni-input)
 131
 132 ;;; arch-tag: e0d91c7c-19a1-43d3-8f2b-28c0e031efaa
 133 ;;; uni-input.el ends here