*** empty log message ***
[emacs.git] / lisp / disp-table.el
blob1acfc8ab8fea6980efcc938071d9b718948c7d7c
1 ;;; disp-table.el --- functions for dealing with char tables.
3 ;; Copyright (C) 1987, 1994, 1995, 1999 Free Software Foundation, Inc.
5 ;; Author: Erik Naggum <erik@naggum.no>
6 ;; Based on a previous version by Howard Gayle
7 ;; Maintainer: FSF
8 ;; Keywords: i18n
10 ;; This file is part of GNU Emacs.
12 ;; GNU Emacs is free software; you can redistribute it and/or modify
13 ;; it under the terms of the GNU General Public License as published by
14 ;; the Free Software Foundation; either version 2, or (at your option)
15 ;; any later version.
17 ;; GNU Emacs is distributed in the hope that it will be useful,
18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 ;; GNU General Public License for more details.
22 ;; You should have received a copy of the GNU General Public License
23 ;; along with GNU Emacs; see the file COPYING. If not, write to the
24 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
25 ;; Boston, MA 02111-1307, USA.
27 ;;; Code:
29 (put 'display-table 'char-table-extra-slots 6)
31 ;;;###autoload
32 (defun make-display-table ()
33 "Return a new, empty display table."
34 (make-char-table 'display-table nil))
36 (or standard-display-table
37 (setq standard-display-table (make-display-table)))
39 ;;; Display-table slot names. The property value says which slot.
41 (put 'truncation 'display-table-slot 0)
42 (put 'wrap 'display-table-slot 1)
43 (put 'escape 'display-table-slot 2)
44 (put 'control 'display-table-slot 3)
45 (put 'selective-display 'display-table-slot 4)
46 (put 'vertical-border 'display-table-slot 5)
48 ;;;###autoload
49 (defun display-table-slot (display-table slot)
50 "Return the value of the extra slot in DISPLAY-TABLE named SLOT.
51 SLOT may be a number from 0 to 5 inclusive, or a slot name (symbol).
52 Valid symbols are `truncation', `wrap', `escape', `control',
53 `selective-display', and `vertical-border'."
54 (let ((slot-number
55 (if (numberp slot) slot
56 (or (get slot 'display-table-slot)
57 (error "Invalid display-table slot name: %s" slot)))))
58 (char-table-extra-slot display-table slot-number)))
60 ;;;###autoload
61 (defun set-display-table-slot (display-table slot value)
62 "Set the value of the extra slot in DISPLAY-TABLE named SLOT to VALUE.
63 SLOT may be a number from 0 to 5 inclusive, or a name (symbol).
64 Valid symbols are `truncation', `wrap', `escape', `control',
65 `selective-display', and `vertical-border'."
66 (let ((slot-number
67 (if (numberp slot) slot
68 (or (get slot 'display-table-slot)
69 (error "Invalid display-table slot name: %s" slot)))))
70 (set-char-table-extra-slot display-table slot-number value)))
72 ;;;###autoload
73 (defun describe-display-table (dt)
74 "Describe the display table DT in a help buffer."
75 (with-output-to-temp-buffer "*Help*"
76 (princ "\nTruncation glyph: ")
77 (prin1 (display-table-slot dt 'truncation))
78 (princ "\nWrap glyph: ")
79 (prin1 (display-table-slot dt 'wrap))
80 (princ "\nEscape glyph: ")
81 (prin1 (display-table-slot dt 'escape))
82 (princ "\nCtrl glyph: ")
83 (prin1 (display-table-slot dt 'control))
84 (princ "\nSelective display glyph sequence: ")
85 (prin1 (display-table-slot dt 'selective-display))
86 (princ "\nVertical window border glyph: ")
87 (prin1 (display-table-slot dt 'vertical-border))
88 (princ "\nCharacter display glyph sequences:\n")
89 (save-excursion
90 (set-buffer standard-output)
91 (let ((vector (make-vector 256 nil))
92 (i 0))
93 (while (< i 256)
94 (aset vector i (aref dt i))
95 (setq i (1+ i)))
96 (describe-vector vector))
97 (help-mode))
98 (print-help-return-message)))
100 ;;;###autoload
101 (defun describe-current-display-table ()
102 "Describe the display table in use in the selected window and buffer."
103 (interactive)
104 (let ((disptab (or (window-display-table (selected-window))
105 buffer-display-table
106 standard-display-table)))
107 (if disptab
108 (describe-display-table disptab)
109 (message "No display table"))))
111 ;;;###autoload
112 (defun standard-display-8bit (l h)
113 "Display characters in the range L to H literally."
114 (while (<= l h)
115 (if (and (>= l ?\ ) (< l 127))
116 (aset standard-display-table l nil)
117 (aset standard-display-table l (vector l)))
118 (setq l (1+ l))))
120 ;;;###autoload
121 (defun standard-display-default (l h)
122 "Display characters in the range L to H using the default notation."
123 (while (<= l h)
124 (if (and (>= l ?\ ) (< l 127))
125 (aset standard-display-table l nil)
126 (aset standard-display-table l nil))
127 (setq l (1+ l))))
129 ;; This function does NOT take terminal-dependent escape sequences.
130 ;; For that, you need to go through create-glyph. Use one of the
131 ;; other functions below, or roll your own.
132 ;;;###autoload
133 (defun standard-display-ascii (c s)
134 "Display character C using printable string S."
135 (aset standard-display-table c (vconcat s)))
137 ;;;###autoload
138 (defun standard-display-g1 (c sc)
139 "Display character C as character SC in the g1 character set.
140 This function assumes that your terminal uses the SO/SI characters;
141 it is meaningless for an X frame."
142 (if (memq window-system '(x w32))
143 (error "Cannot use string glyphs in a windowing system"))
144 (aset standard-display-table c
145 (vector (create-glyph (concat "\016" (char-to-string sc) "\017")))))
147 ;;;###autoload
148 (defun standard-display-graphic (c gc)
149 "Display character C as character GC in graphics character set.
150 This function assumes VT100-compatible escapes; it is meaningless for an
151 X frame."
152 (if (memq window-system '(x w32))
153 (error "Cannot use string glyphs in a windowing system"))
154 (aset standard-display-table c
155 (vector (create-glyph (concat "\e(0" (char-to-string gc) "\e(B")))))
157 ;;;###autoload
158 (defun standard-display-underline (c uc)
159 "Display character C as character UC plus underlining."
160 (aset standard-display-table c
161 (vector
162 (if window-system
163 (logior uc (lsh (face-id 'underline) 19))
164 (create-glyph (concat "\e[4m" (char-to-string uc) "\e[m"))))))
166 ;;;###autoload
167 (defun create-glyph (string)
168 "Allocate a glyph code to display by sending STRING to the terminal."
169 (if (= (length glyph-table) 65536)
170 (error "No free glyph codes remain"))
171 ;; Don't use slots that correspond to ASCII characters.
172 (if (= (length glyph-table) 32)
173 (setq glyph-table (vconcat glyph-table (make-vector 224 nil))))
174 (setq glyph-table (vconcat glyph-table (list string)))
175 (1- (length glyph-table)))
177 ;;;###autoload
178 (defun standard-display-european (arg)
179 "Semi-obsolete way to toggle display of ISO 8859 European characters.
181 This function is semi-obsolete; if you want to do your editing with
182 unibyte characters, it is better to `set-language-environment' coupled
183 with either the `--unibyte' option or the EMACS_UNIBYTE environment
184 variable, or else customize `enable-multibyte-characters'.
186 With prefix argument, this command enables European character display
187 if arg is positive, disables it otherwise. Otherwise, it toggles
188 European character display.
190 When this mode is enabled, characters in the range of 160 to 255
191 display not as octal escapes, but as accented characters. Codes 146
192 and 160 display as apostrophe and space, even though they are not the
193 ASCII codes for apostrophe and space.
195 Enabling European character display with this command noninteractively
196 from Lisp code also selects Latin-1 as the language environment, and
197 selects unibyte mode for all Emacs buffers \(both existing buffers and
198 those created subsequently). This provides increased compatibility
199 for users who call this function in `.emacs'."
201 (if (or (<= (prefix-numeric-value arg) 0)
202 (and (null arg)
203 (char-table-p standard-display-table)
204 ;; Test 161, because 160 displays as a space.
205 (equal (aref standard-display-table 161) [161])))
206 (progn
207 (standard-display-default 160 255)
208 (unless (or (memq window-system '(x w32))
209 (interactive-p))
210 (and (terminal-coding-system)
211 (set-terminal-coding-system nil))))
212 ;; If the user does this explicitly from Lisp (as in .emacs),
213 ;; turn off multibyte chars for more compatibility.
214 (unless (interactive-p)
215 (setq-default enable-multibyte-characters nil)
216 (mapcar (lambda (buffer)
217 (with-current-buffer buffer
218 (if enable-multibyte-characters
219 (set-buffer-multibyte nil))))
220 (buffer-list)))
221 ;; If the user does this explicitly,
222 ;; switch to Latin-1 language environment
223 ;; unless some other has been specified.
224 (unless (interactive-p)
225 (if (equal current-language-environment "English")
226 (set-language-environment "latin-1")))
227 (unless (or noninteractive (memq window-system '(x w32))
228 (interactive-p))
229 ;; Send those codes literally to a character-based terminal.
230 ;; If we are using single-byte characters,
231 ;; it doesn't matter which coding system we use.
232 (set-terminal-coding-system
233 (let ((c (intern (downcase current-language-environment))))
234 (if (coding-system-p c) c 'latin-1))))
235 (standard-display-european-internal)))
237 (provide 'disp-table)
239 ;;; disp-table.el ends here