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1a06eabd ER |
1 | ;;; help.el --- help commands for Emacs |
2 | ||
73b0cd50 | 3 | ;; Copyright (C) 1985-1986, 1993-1994, 1998-2011 |
e9bffc61 | 4 | ;; Free Software Foundation, Inc. |
3a801d0c | 5 | |
e5167999 | 6 | ;; Maintainer: FSF |
fd7fa35a | 7 | ;; Keywords: help, internal |
bd78fa1d | 8 | ;; Package: emacs |
e5167999 | 9 | |
433ae6f6 RS |
10 | ;; This file is part of GNU Emacs. |
11 | ||
eb3fa2cf | 12 | ;; GNU Emacs is free software: you can redistribute it and/or modify |
433ae6f6 | 13 | ;; it under the terms of the GNU General Public License as published by |
eb3fa2cf GM |
14 | ;; the Free Software Foundation, either version 3 of the License, or |
15 | ;; (at your option) any later version. | |
433ae6f6 RS |
16 | |
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. | |
21 | ||
22 | ;; You should have received a copy of the GNU General Public License | |
eb3fa2cf | 23 | ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. |
433ae6f6 | 24 | |
d9ecc911 ER |
25 | ;;; Commentary: |
26 | ||
a1c9f209 | 27 | ;; This code implements GNU Emacs' on-line help system, the one invoked by |
95ac0a6f | 28 | ;; `M-x help-for-help'. |
d9ecc911 | 29 | |
e5167999 ER |
30 | ;;; Code: |
31 | ||
8aa3a187 RS |
32 | ;; Get the macro make-help-screen when this is compiled, |
33 | ;; or run interpreted, but not when the compiled code is loaded. | |
b1fe9304 | 34 | (eval-when-compile (require 'help-macro)) |
788d62cf MB |
35 | |
36 | ;; This makes `with-output-to-temp-buffer' buffers use `help-mode'. | |
37 | (add-hook 'temp-buffer-setup-hook 'help-mode-setup) | |
38 | (add-hook 'temp-buffer-show-hook 'help-mode-finish) | |
41b8542b | 39 | |
cde56121 MR |
40 | ;; The variable `help-window' below is used by `help-mode-finish' to |
41 | ;; communicate the window displaying help (the "help window") to the | |
42 | ;; macro `with-help-window'. The latter sets `help-window' to t before | |
43 | ;; invoking `with-output-to-temp-buffer'. If and only if `help-window' | |
44 | ;; is eq to t, `help-mode-finish' (called by `temp-buffer-setup-hook') | |
45 | ;; sets `help-window' to the window selected by `display-buffer'. | |
b3d8e4a0 | 46 | ;; Exiting `with-help-window' and calling `help-print-return-message' |
cde56121 MR |
47 | ;; reset `help-window' to nil. |
48 | (defvar help-window nil | |
49 | "Window chosen for displaying help.") | |
50 | ||
51 | ;; `help-window-point-marker' is a marker you can move to a valid | |
52 | ;; position of the buffer shown in the help window in order to override | |
53 | ;; the standard positioning mechanism (`point-min') chosen by | |
54 | ;; `with-output-to-temp-buffer'. `with-help-window' has this point | |
55 | ;; nowhere before exiting. Currently used by `view-lossage' to assert | |
56 | ;; that the last keystrokes are always visible. | |
7b01c8d7 | 57 | (defvar help-window-point-marker (make-marker) |
cde56121 MR |
58 | "Marker to override default `window-point' of `help-window'.") |
59 | ||
604aa5f0 SM |
60 | (defvar help-map |
61 | (let ((map (make-sparse-keymap))) | |
62 | (define-key map (char-to-string help-char) 'help-for-help) | |
63 | (define-key map [help] 'help-for-help) | |
64 | (define-key map [f1] 'help-for-help) | |
65 | (define-key map "." 'display-local-help) | |
66 | (define-key map "?" 'help-for-help) | |
67 | ||
d4a18332 | 68 | (define-key map "\C-a" 'about-emacs) |
604aa5f0 | 69 | (define-key map "\C-c" 'describe-copying) |
7b01c8d7 KS |
70 | (define-key map "\C-d" 'view-emacs-debugging) |
71 | (define-key map "\C-e" 'view-external-packages) | |
604aa5f0 SM |
72 | (define-key map "\C-f" 'view-emacs-FAQ) |
73 | (define-key map "\C-m" 'view-order-manuals) | |
74 | (define-key map "\C-n" 'view-emacs-news) | |
7b01c8d7 KS |
75 | (define-key map "\C-o" 'describe-distribution) |
76 | (define-key map "\C-p" 'view-emacs-problems) | |
77 | (define-key map "\C-t" 'view-emacs-todo) | |
604aa5f0 SM |
78 | (define-key map "\C-w" 'describe-no-warranty) |
79 | ||
80 | ;; This does not fit the pattern, but it is natural given the C-\ command. | |
81 | (define-key map "\C-\\" 'describe-input-method) | |
82 | ||
83 | (define-key map "C" 'describe-coding-system) | |
84 | (define-key map "F" 'Info-goto-emacs-command-node) | |
85 | (define-key map "I" 'describe-input-method) | |
86 | (define-key map "K" 'Info-goto-emacs-key-command-node) | |
87 | (define-key map "L" 'describe-language-environment) | |
88 | (define-key map "S" 'info-lookup-symbol) | |
89 | ||
90 | (define-key map "a" 'apropos-command) | |
91 | (define-key map "b" 'describe-bindings) | |
92 | (define-key map "c" 'describe-key-briefly) | |
93 | (define-key map "d" 'apropos-documentation) | |
94 | (define-key map "e" 'view-echo-area-messages) | |
95 | (define-key map "f" 'describe-function) | |
7b01c8d7 | 96 | (define-key map "g" 'describe-gnu-project) |
604aa5f0 SM |
97 | (define-key map "h" 'view-hello-file) |
98 | ||
99 | (define-key map "i" 'info) | |
100 | (define-key map "4i" 'info-other-window) | |
101 | ||
102 | (define-key map "k" 'describe-key) | |
103 | (define-key map "l" 'view-lossage) | |
104 | (define-key map "m" 'describe-mode) | |
105 | (define-key map "n" 'view-emacs-news) | |
106 | (define-key map "p" 'finder-by-keyword) | |
cb6c4991 | 107 | (define-key map "P" 'describe-package) |
604aa5f0 SM |
108 | (define-key map "r" 'info-emacs-manual) |
109 | (define-key map "s" 'describe-syntax) | |
110 | (define-key map "t" 'help-with-tutorial) | |
111 | (define-key map "w" 'where-is) | |
112 | (define-key map "v" 'describe-variable) | |
113 | (define-key map "q" 'help-quit) | |
114 | map) | |
433ae6f6 RS |
115 | "Keymap for characters following the Help key.") |
116 | ||
e17d2fd1 | 117 | (define-key global-map (char-to-string help-char) 'help-command) |
0af3df1c RS |
118 | (define-key global-map [help] 'help-command) |
119 | (define-key global-map [f1] 'help-command) | |
433ae6f6 RS |
120 | (fset 'help-command help-map) |
121 | ||
e25e90b4 DP |
122 | ;; insert-button makes the action nil if it is not store somewhere |
123 | (defvar help-button-cache nil) | |
124 | ||
0cf0d828 | 125 | \f |
2fc9d9f4 | 126 | (defun help-quit () |
3120a677 | 127 | "Just exit from the Help command's command loop." |
2fc9d9f4 RS |
128 | (interactive) |
129 | nil) | |
130 | ||
01364a75 RS |
131 | (defvar help-return-method nil |
132 | "What to do to \"exit\" the help buffer. | |
133 | This is a list | |
a8e7142c EZ |
134 | (WINDOW . t) delete the selected window (and possibly its frame, |
135 | see `quit-window' and `View-quit'), go to WINDOW. | |
01364a75 RS |
136 | (WINDOW . quit-window) do quit-window, then select WINDOW. |
137 | (WINDOW BUF START POINT) display BUF at START, POINT, then select WINDOW.") | |
138 | ||
b3d8e4a0 SM |
139 | (define-obsolete-function-alias 'print-help-return-message 'help-print-return-message "23.2") |
140 | (defun help-print-return-message (&optional function) | |
433ae6f6 | 141 | "Display or return message saying how to restore windows after help command. |
d009b6e9 RS |
142 | This function assumes that `standard-output' is the help buffer. |
143 | It computes a message, and applies the optional argument FUNCTION to it. | |
a8e7142c EZ |
144 | If FUNCTION is nil, it applies `message', thus displaying the message. |
145 | In addition, this function sets up `help-return-method', which see, that | |
146 | specifies what to do when the user exits the help buffer." | |
cde56121 MR |
147 | ;; Reset `help-window' here to avoid confusing `help-mode-finish'. |
148 | (setq help-window nil) | |
433ae6f6 | 149 | (and (not (get-buffer-window standard-output)) |
d536293f | 150 | (let ((first-message |
a8e7142c EZ |
151 | (cond ((or |
152 | pop-up-frames | |
153 | (special-display-p (buffer-name standard-output))) | |
01364a75 | 154 | (setq help-return-method (cons (selected-window) t)) |
d536293f RS |
155 | ;; If the help output buffer is a special display buffer, |
156 | ;; don't say anything about how to get rid of it. | |
157 | ;; First of all, the user will do that with the window | |
158 | ;; manager, not with Emacs. | |
159 | ;; Secondly, the buffer has not been displayed yet, | |
160 | ;; so we don't know whether its frame will be selected. | |
d536293f | 161 | nil) |
f3ad2fc8 GM |
162 | (display-buffer-reuse-frames |
163 | (setq help-return-method (cons (selected-window) | |
164 | 'quit-window)) | |
165 | nil) | |
d536293f | 166 | ((not (one-window-p t)) |
01364a75 RS |
167 | (setq help-return-method |
168 | (cons (selected-window) 'quit-window)) | |
cb0b6766 | 169 | "Type \\[display-buffer] RET to restore the other window.") |
d536293f | 170 | (pop-up-windows |
01364a75 | 171 | (setq help-return-method (cons (selected-window) t)) |
d536293f RS |
172 | "Type \\[delete-other-windows] to remove help window.") |
173 | (t | |
01364a75 RS |
174 | (setq help-return-method |
175 | (list (selected-window) (window-buffer) | |
176 | (window-start) (window-point))) | |
d536293f RS |
177 | "Type \\[switch-to-buffer] RET to remove help window.")))) |
178 | (funcall (or function 'message) | |
179 | (concat | |
180 | (if first-message | |
376b2a24 DL |
181 | (substitute-command-keys first-message)) |
182 | (if first-message " ") | |
125a8d70 RS |
183 | ;; If the help buffer will go in a separate frame, |
184 | ;; it's no use mentioning a command to scroll, so don't. | |
7b057a3d EZ |
185 | (if (or pop-up-windows |
186 | (special-display-p (buffer-name standard-output))) | |
125a8d70 | 187 | nil |
a1c9f209 | 188 | (if (same-window-p (buffer-name standard-output)) |
125a8d70 RS |
189 | ;; Say how to scroll this window. |
190 | (substitute-command-keys | |
191 | "\\[scroll-up] to scroll the help.") | |
192 | ;; Say how to scroll some other window. | |
6e7f5182 | 193 | (substitute-command-keys |
125a8d70 | 194 | "\\[scroll-other-window] to scroll the help.")))))))) |
433ae6f6 | 195 | |
433ae6f6 RS |
196 | ;; So keyboard macro definitions are documented correctly |
197 | (fset 'defining-kbd-macro (symbol-function 'start-kbd-macro)) | |
198 | ||
a4bdcdf3 RS |
199 | (defalias 'help 'help-for-help-internal) |
200 | ;; find-function can find this. | |
201 | (defalias 'help-for-help 'help-for-help-internal) | |
202 | ;; It can't find this, but nobody will look. | |
203 | (make-help-screen help-for-help-internal | |
9cd39aff | 204 | (purecopy "Type a help option: [abcCdefFgiIkKlLmnprstvw.] C-[cdefmnoptw] or ?") |
ce9a0ccb SM |
205 | ;; Don't purecopy this one, because it's not evaluated (it's |
206 | ;; directly used as a docstring in a function definition, so it'll | |
207 | ;; be moved to the DOC file anyway: no need for purecopying it). | |
788d62cf MB |
208 | "You have typed %THIS-KEY%, the help character. Type a Help option: |
209 | \(Use SPC or DEL to scroll through this text. Type \\<help-map>\\[help-quit] to exit the Help command.) | |
210 | ||
7b01c8d7 KS |
211 | a PATTERN Show commands whose name matches the PATTERN (a list of words |
212 | or a regexp). See also the `apropos' command. | |
213 | b Display all key bindings. | |
214 | c KEYS Display the command name run by the given key sequence. | |
215 | C CODING Describe the given coding system, or RET for current ones. | |
216 | d PATTERN Show a list of functions, variables, and other items whose | |
217 | documentation matches the PATTERN (a list of words or a regexp). | |
218 | e Go to the *Messages* buffer which logs echo-area messages. | |
219 | f FUNCTION Display documentation for the given function. | |
220 | F COMMAND Show the on-line manual's section that describes the command. | |
221 | g Display information about the GNU project. | |
222 | h Display the HELLO file which illustrates various scripts. | |
223 | i Start the Info documentation reader: read on-line manuals. | |
224 | I METHOD Describe a specific input method, or RET for current. | |
225 | k KEYS Display the full documentation for the key sequence. | |
226 | K KEYS Show the on-line manual's section for the command bound to KEYS. | |
90ad3541 | 227 | l Show last 300 input keystrokes (lossage). |
7b01c8d7 KS |
228 | L LANG-ENV Describes a specific language environment, or RET for current. |
229 | m Display documentation of current minor modes and current major mode, | |
230 | including their special commands. | |
231 | n Display news of recent Emacs changes. | |
232 | p TOPIC Find packages matching a given topic keyword. | |
233 | r Display the Emacs manual in Info mode. | |
234 | s Display contents of current syntax table, plus explanations. | |
235 | S SYMBOL Show the section for the given symbol in the on-line manual | |
236 | for the programming language used in this buffer. | |
237 | t Start the Emacs learn-by-doing tutorial. | |
238 | v VARIABLE Display the given variable's documentation and value. | |
239 | w COMMAND Display which keystrokes invoke the given command (where-is). | |
240 | . Display any available local help at point in the echo area. | |
241 | ||
242 | C-a Information about Emacs. | |
243 | C-c Emacs copying permission (GNU General Public License). | |
244 | C-d Instructions for debugging GNU Emacs. | |
245 | C-e External packages and information about Emacs. | |
246 | C-f Emacs FAQ. | |
247 | C-m How to order printed Emacs manuals. | |
248 | C-n News of recent Emacs changes. | |
249 | C-o Emacs ordering and distribution information. | |
250 | C-p Info about known Emacs problems. | |
251 | C-t Emacs TODO list. | |
ce9a0ccb | 252 | C-w Information on absence of warranty for GNU Emacs." |
788d62cf MB |
253 | help-map) |
254 | ||
255 | \f | |
256 | ||
257 | (defun function-called-at-point () | |
258 | "Return a function around point or else called by the list containing point. | |
259 | If that doesn't give a function, return nil." | |
2e6750c8 SM |
260 | (with-syntax-table emacs-lisp-mode-syntax-table |
261 | (or (condition-case () | |
262 | (save-excursion | |
263 | (or (not (zerop (skip-syntax-backward "_w"))) | |
264 | (eq (char-syntax (following-char)) ?w) | |
265 | (eq (char-syntax (following-char)) ?_) | |
266 | (forward-sexp -1)) | |
267 | (skip-chars-forward "'") | |
268 | (let ((obj (read (current-buffer)))) | |
269 | (and (symbolp obj) (fboundp obj) obj))) | |
270 | (error nil)) | |
271 | (condition-case () | |
272 | (save-excursion | |
273 | (save-restriction | |
274 | (narrow-to-region (max (point-min) | |
275 | (- (point) 1000)) (point-max)) | |
276 | ;; Move up to surrounding paren, then after the open. | |
277 | (backward-up-list 1) | |
278 | (forward-char 1) | |
279 | ;; If there is space here, this is probably something | |
280 | ;; other than a real Lisp function call, so ignore it. | |
281 | (if (looking-at "[ \t]") | |
282 | (error "Probably not a Lisp function call")) | |
283 | (let ((obj (read (current-buffer)))) | |
284 | (and (symbolp obj) (fboundp obj) obj)))) | |
285 | (error nil)) | |
286 | (let* ((str (find-tag-default)) | |
287 | (sym (if str (intern-soft str)))) | |
288 | (if (and sym (fboundp sym)) | |
289 | sym | |
290 | (save-match-data | |
291 | (when (and str (string-match "\\`\\W*\\(.*?\\)\\W*\\'" str)) | |
292 | (setq sym (intern-soft (match-string 1 str))) | |
293 | (and (fboundp sym) sym)))))))) | |
788d62cf MB |
294 | |
295 | \f | |
296 | ;;; `User' help functions | |
297 | ||
7b01c8d7 KS |
298 | (defun view-help-file (file &optional dir) |
299 | (view-file (expand-file-name file (or dir data-directory))) | |
3ffb948c | 300 | (goto-address-mode 1) |
7b01c8d7 KS |
301 | (goto-char (point-min))) |
302 | ||
433ae6f6 RS |
303 | (defun describe-distribution () |
304 | "Display info on how to obtain the latest version of GNU Emacs." | |
305 | (interactive) | |
7b01c8d7 | 306 | (view-help-file "DISTRIB")) |
433ae6f6 RS |
307 | |
308 | (defun describe-copying () | |
309 | "Display info on how you may redistribute copies of GNU Emacs." | |
310 | (interactive) | |
7b01c8d7 | 311 | (view-help-file "COPYING")) |
433ae6f6 | 312 | |
7b01c8d7 | 313 | (defun describe-gnu-project () |
76766f2d RS |
314 | "Display info on the GNU project." |
315 | (interactive) | |
7b01c8d7 | 316 | (view-help-file "THE-GNU-PROJECT")) |
76766f2d | 317 | |
4e44f5ce KS |
318 | (define-obsolete-function-alias 'describe-project 'describe-gnu-project "22.2") |
319 | ||
433ae6f6 RS |
320 | (defun describe-no-warranty () |
321 | "Display info on all the kinds of warranty Emacs does NOT have." | |
322 | (interactive) | |
323 | (describe-copying) | |
324 | (let (case-fold-search) | |
e7e2b26c GM |
325 | (search-forward "Disclaimer of Warranty") |
326 | (forward-line 0) | |
433ae6f6 RS |
327 | (recenter 0))) |
328 | ||
61c6b658 | 329 | (defun describe-prefix-bindings () |
c7cba9cb RS |
330 | "Describe the bindings of the prefix used to reach this command. |
331 | The prefix described consists of all but the last event | |
332 | of the key sequence that ran this command." | |
61c6b658 | 333 | (interactive) |
0f101663 | 334 | (let ((key (this-command-keys))) |
ccc06dcc KH |
335 | (describe-bindings |
336 | (if (stringp key) | |
337 | (substring key 0 (1- (length key))) | |
338 | (let ((prefix (make-vector (1- (length key)) nil)) | |
339 | (i 0)) | |
340 | (while (< i (length prefix)) | |
341 | (aset prefix i (aref key i)) | |
342 | (setq i (1+ i))) | |
343 | prefix))))) | |
788d62cf | 344 | ;; Make C-h after a prefix, when not specifically bound, |
c7cba9cb | 345 | ;; run describe-prefix-bindings. |
61c6b658 RS |
346 | (setq prefix-help-command 'describe-prefix-bindings) |
347 | ||
e38cc268 | 348 | (defun view-emacs-news (&optional version) |
382d018a | 349 | "Display info on recent changes to Emacs. |
598ea453 | 350 | With argument, display info only for the selected version." |
382d018a | 351 | (interactive "P") |
e38cc268 KS |
352 | (unless version |
353 | (setq version emacs-major-version)) | |
354 | (when (consp version) | |
355 | (let* ((all-versions | |
356 | (let (res) | |
cc6650af | 357 | (mapc |
e38cc268 KS |
358 | (lambda (file) |
359 | (with-temp-buffer | |
360 | (insert-file-contents | |
361 | (expand-file-name file data-directory)) | |
362 | (while (re-search-forward | |
363 | (if (member file '("NEWS.18" "NEWS.1-17")) | |
364 | "Changes in \\(?:Emacs\\|version\\)?[ \t]*\\([0-9]+\\(?:\\.[0-9]+\\)?\\)" | |
365 | "^\* [^0-9\n]*\\([0-9]+\\.[0-9]+\\)") nil t) | |
366 | (setq res (cons (match-string-no-properties 1) res))))) | |
367 | (cons "NEWS" | |
368 | (directory-files data-directory nil | |
369 | "^NEWS\\.[0-9][-0-9]*$" nil))) | |
370 | (sort (delete-dups res) (lambda (a b) (string< b a))))) | |
8c9fc4be | 371 | (current (car all-versions))) |
e38cc268 KS |
372 | (setq version (completing-read |
373 | (format "Read NEWS for the version (default %s): " current) | |
374 | all-versions nil nil nil nil current)) | |
375 | (if (integerp (string-to-number version)) | |
376 | (setq version (string-to-number version)) | |
377 | (unless (or (member version all-versions) | |
378 | (<= (string-to-number version) (string-to-number current))) | |
379 | (error "No news about version %s" version))))) | |
380 | (when (integerp version) | |
381 | (cond ((<= version 12) | |
382 | (setq version (format "1.%d" version))) | |
383 | ((<= version 18) | |
384 | (setq version (format "%d" version))) | |
385 | ((> version emacs-major-version) | |
e08b54f2 | 386 | (error "No news about Emacs %d (yet)" version)))) |
e38cc268 KS |
387 | (let* ((vn (if (stringp version) |
388 | (string-to-number version) | |
389 | version)) | |
390 | (file (cond | |
391 | ((>= vn emacs-major-version) "NEWS") | |
392 | ((< vn 18) "NEWS.1-17") | |
8c9fc4be KS |
393 | (t (format "NEWS.%d" vn)))) |
394 | res) | |
e38cc268 KS |
395 | (view-file (expand-file-name file data-directory)) |
396 | (widen) | |
397 | (goto-char (point-min)) | |
398 | (when (stringp version) | |
399 | (when (re-search-forward | |
400 | (concat (if (< vn 19) | |
401 | "Changes in Emacs[ \t]*" | |
402 | "^\* [^0-9\n]*") version "$") | |
403 | nil t) | |
404 | (beginning-of-line) | |
405 | (narrow-to-region | |
406 | (point) | |
407 | (save-excursion | |
408 | (while (and (setq res | |
409 | (re-search-forward | |
410 | (if (< vn 19) | |
411 | "Changes in \\(?:Emacs\\|version\\)?[ \t]*\\([0-9]+\\(?:\\.[0-9]+\\)?\\)" | |
412 | "^\* [^0-9\n]*\\([0-9]+\\.[0-9]+\\)") nil t)) | |
413 | (equal (match-string-no-properties 1) version))) | |
414 | (or res (goto-char (point-max))) | |
415 | (beginning-of-line) | |
416 | (point))))))) | |
417 | ||
7b01c8d7 | 418 | (defun view-emacs-todo (&optional arg) |
1ebc1f01 RS |
419 | "Display the Emacs TODO list." |
420 | (interactive "P") | |
7b01c8d7 | 421 | (view-help-file "TODO")) |
1ebc1f01 | 422 | |
4e44f5ce KS |
423 | (define-obsolete-function-alias 'view-todo 'view-emacs-todo "22.2") |
424 | ||
425 | ||
4f16ea85 RS |
426 | (defun view-echo-area-messages () |
427 | "View the log of recent echo-area messages: the `*Messages*' buffer. | |
428 | The number of messages retained in that buffer | |
429 | is specified by the variable `message-log-max'." | |
430 | (interactive) | |
431 | (switch-to-buffer (get-buffer-create "*Messages*"))) | |
432 | ||
754084bb GM |
433 | (defun view-order-manuals () |
434 | "Display the Emacs ORDERS file." | |
435 | (interactive) | |
7b01c8d7 | 436 | (view-help-file "ORDERS")) |
754084bb | 437 | |
7ee71cf1 RS |
438 | (defun view-emacs-FAQ () |
439 | "Display the Emacs Frequently Asked Questions (FAQ) file." | |
440 | (interactive) | |
94ea540b | 441 | ;; (find-file-read-only (expand-file-name "FAQ" data-directory)) |
279b772d | 442 | (info "(efaq)")) |
7ee71cf1 | 443 | |
4cbff657 DL |
444 | (defun view-emacs-problems () |
445 | "Display info on known problems with Emacs and possible workarounds." | |
446 | (interactive) | |
7b01c8d7 KS |
447 | (view-help-file "PROBLEMS")) |
448 | ||
449 | (defun view-emacs-debugging () | |
450 | "Display info on how to debug Emacs problems." | |
451 | (interactive) | |
452 | (view-help-file "DEBUG")) | |
453 | ||
454 | (defun view-external-packages () | |
455 | "Display external packages and information about Emacs." | |
456 | (interactive) | |
457 | (view-help-file "MORE.STUFF")) | |
4cbff657 | 458 | |
433ae6f6 | 459 | (defun view-lossage () |
6b8d1c72 | 460 | "Display last 300 input keystrokes. |
50b57199 EZ |
461 | |
462 | To record all your input on a file, use `open-dribble-file'." | |
433ae6f6 | 463 | (interactive) |
32226619 JB |
464 | (help-setup-xref (list #'view-lossage) |
465 | (called-interactively-p 'interactive)) | |
cde56121 | 466 | (with-help-window (help-buffer) |
02dfca16 SM |
467 | (princ (mapconcat (lambda (key) |
468 | (if (or (integerp key) (symbolp key) (listp key)) | |
469 | (single-key-description key) | |
470 | (prin1-to-string key nil))) | |
298a7c8c RS |
471 | (recent-keys) |
472 | " ")) | |
b0fbf754 | 473 | (with-current-buffer standard-output |
433ae6f6 RS |
474 | (goto-char (point-min)) |
475 | (while (progn (move-to-column 50) (not (eobp))) | |
e5fe3a6c JB |
476 | (when (search-forward " " nil t) |
477 | (delete-char -1)) | |
cde56121 MR |
478 | (insert "\n")) |
479 | ;; jidanni wants to see the last keystrokes immediately. | |
480 | (set-marker help-window-point-marker (point))))) | |
433ae6f6 | 481 | |
788d62cf MB |
482 | \f |
483 | ;; Key bindings | |
433ae6f6 | 484 | |
4c45295b | 485 | (defun describe-bindings (&optional prefix buffer) |
a8ad43aa RS |
486 | "Show a list of all defined keys, and their definitions. |
487 | We put that list in a buffer, and display the buffer. | |
488 | ||
489 | The optional argument PREFIX, if non-nil, should be a key sequence; | |
4c45295b KH |
490 | then we display only bindings that start with that prefix. |
491 | The optional argument BUFFER specifies which buffer's bindings | |
abca4ad7 LT |
492 | to display (default, the current buffer). BUFFER can be a buffer |
493 | or a buffer name." | |
3e5929af | 494 | (interactive) |
4c45295b | 495 | (or buffer (setq buffer (current-buffer))) |
32226619 JB |
496 | (help-setup-xref (list #'describe-bindings prefix buffer) |
497 | (called-interactively-p 'interactive)) | |
4c45295b | 498 | (with-current-buffer buffer |
3e5929af | 499 | (describe-bindings-internal nil prefix))) |
a8ad43aa | 500 | |
94ea540b SM |
501 | ;; This function used to be in keymap.c. |
502 | (defun describe-bindings-internal (&optional menus prefix) | |
503 | "Show a list of all defined keys, and their definitions. | |
504 | We put that list in a buffer, and display the buffer. | |
505 | ||
506 | The optional argument MENUS, if non-nil, says to mention menu bindings. | |
507 | \(Ordinarily these are omitted from the output.) | |
508 | The optional argument PREFIX, if non-nil, should be a key sequence; | |
509 | then we display only bindings that start with that prefix." | |
94ea540b | 510 | (let ((buf (current-buffer))) |
cde56121 | 511 | (with-help-window "*Help*" |
94ea540b SM |
512 | (with-current-buffer standard-output |
513 | (describe-buffer-bindings buf prefix menus))))) | |
514 | ||
e88a2c59 | 515 | (defun where-is (definition &optional insert) |
b2c85790 | 516 | "Print message listing key sequences that invoke the command DEFINITION. |
e88a2c59 RS |
517 | Argument is a command definition, usually a symbol with a function definition. |
518 | If INSERT (the prefix arg) is non-nil, insert the message in the buffer." | |
54c0b967 RS |
519 | (interactive |
520 | (let ((fn (function-called-at-point)) | |
788d62cf | 521 | (enable-recursive-minibuffers t) |
54c0b967 | 522 | val) |
3829bcc5 SM |
523 | (setq val (completing-read |
524 | (if fn | |
525 | (format "Where is command (default %s): " fn) | |
526 | "Where is command: ") | |
527 | obarray 'commandp t)) | |
528 | (list (if (equal val "") fn (intern val)) current-prefix-arg))) | |
463d75ac | 529 | (unless definition (error "No command")) |
7a698dc1 | 530 | (let ((func (indirect-function definition)) |
3829bcc5 | 531 | (defs nil) |
7a698dc1 | 532 | (standard-output (if insert (current-buffer) t))) |
740b479c | 533 | ;; In DEFS, find all symbols that are aliases for DEFINITION. |
3829bcc5 SM |
534 | (mapatoms (lambda (symbol) |
535 | (and (fboundp symbol) | |
536 | (not (eq symbol definition)) | |
d92c2757 RS |
537 | (eq func (condition-case () |
538 | (indirect-function symbol) | |
539 | (error symbol))) | |
3829bcc5 | 540 | (push symbol defs)))) |
740b479c RS |
541 | ;; Look at all the symbols--first DEFINITION, |
542 | ;; then its aliases. | |
543 | (dolist (symbol (cons definition defs)) | |
544 | (let* ((remapped (command-remapping symbol)) | |
545 | (keys (where-is-internal | |
546 | symbol overriding-local-map nil nil remapped)) | |
547 | (keys (mapconcat 'key-description keys ", ")) | |
548 | string) | |
549 | (setq string | |
550 | (if insert | |
551 | (if (> (length keys) 0) | |
552 | (if remapped | |
553 | (format "%s (%s) (remapped from %s)" | |
554 | keys remapped symbol) | |
555 | (format "%s (%s)" keys symbol)) | |
556 | (format "M-x %s RET" symbol)) | |
557 | (if (> (length keys) 0) | |
558 | (if remapped | |
559 | (format "%s is remapped to %s which is on %s" | |
a5f43550 | 560 | symbol remapped keys) |
740b479c RS |
561 | (format "%s is on %s" symbol keys)) |
562 | ;; If this is the command the user asked about, | |
563 | ;; and it is not on any key, say so. | |
564 | ;; For other symbols, its aliases, say nothing | |
565 | ;; about them unless they are on keys. | |
566 | (if (eq symbol definition) | |
567 | (format "%s is not on any key" symbol))))) | |
568 | (when string | |
569 | (unless (eq symbol definition) | |
570 | (princ ";\n its alias ")) | |
571 | (princ string))))) | |
54c0b967 RS |
572 | nil) |
573 | ||
02dfca16 SM |
574 | (defun help-key-description (key untranslated) |
575 | (let ((string (key-description key))) | |
ae1bb8ac SM |
576 | (if (or (not untranslated) |
577 | (and (eq (aref untranslated 0) ?\e) (not (eq (aref key 0) ?\e)))) | |
02dfca16 SM |
578 | string |
579 | (let ((otherstring (key-description untranslated))) | |
580 | (if (equal string otherstring) | |
581 | string | |
582 | (format "%s (translated from %s)" string otherstring)))))) | |
71296446 | 583 | |
6527c983 EZ |
584 | (defun describe-key-briefly (&optional key insert untranslated) |
585 | "Print the name of the function KEY invokes. KEY is a string. | |
586 | If INSERT (the prefix arg) is non-nil, insert the message in the buffer. | |
587 | If non-nil, UNTRANSLATED is a vector of the untranslated events. | |
588 | It can also be a number in which case the untranslated events from | |
589 | the last key hit are used. | |
590 | ||
591 | If KEY is a menu item or a tool-bar button that is disabled, this command | |
8ee320fc | 592 | temporarily enables it to allow getting help on disabled items and buttons." |
2c8ed538 RS |
593 | (interactive |
594 | (let ((enable-disabled-menus-and-buttons t) | |
595 | (cursor-in-echo-area t) | |
596 | saved-yank-menu) | |
597 | (unwind-protect | |
598 | (let (key) | |
599 | ;; If yank-menu is empty, populate it temporarily, so that | |
600 | ;; "Select and Paste" menu can generate a complete event. | |
601 | (when (null (cdr yank-menu)) | |
602 | (setq saved-yank-menu (copy-sequence yank-menu)) | |
603 | (menu-bar-update-yank-menu "(any string)" nil)) | |
604 | (setq key (read-key-sequence "Describe key (or click or menu item): ")) | |
46d91fa0 | 605 | ;; If KEY is a down-event, read and discard the |
91a2acb2 DK |
606 | ;; corresponding up-event. Note that there are also |
607 | ;; down-events on scroll bars and mode lines: the actual | |
608 | ;; event then is in the second element of the vector. | |
609 | (and (vectorp key) | |
badf89ea RS |
610 | (let ((last-idx (1- (length key)))) |
611 | (and (eventp (aref key last-idx)) | |
612 | (memq 'down (event-modifiers (aref key last-idx))))) | |
91a2acb2 | 613 | (read-event)) |
2c8ed538 RS |
614 | (list |
615 | key | |
774a814f RS |
616 | (if current-prefix-arg (prefix-numeric-value current-prefix-arg)) |
617 | 1)) | |
2c8ed538 RS |
618 | ;; Put yank-menu back as it was, if we changed it. |
619 | (when saved-yank-menu | |
620 | (setq yank-menu (copy-sequence saved-yank-menu)) | |
621 | (fset 'yank-menu (cons 'keymap yank-menu)))))) | |
02dfca16 SM |
622 | (if (numberp untranslated) |
623 | (setq untranslated (this-single-command-raw-keys))) | |
91a2acb2 DK |
624 | (let* ((event (if (and (symbolp (aref key 0)) |
625 | (> (length key) 1) | |
626 | (consp (aref key 1))) | |
627 | (aref key 1) | |
628 | (aref key 0))) | |
629 | (modifiers (event-modifiers event)) | |
630 | (standard-output (if insert (current-buffer) t)) | |
24a27882 KS |
631 | (mouse-msg (if (or (memq 'click modifiers) (memq 'down modifiers) |
632 | (memq 'drag modifiers)) " at that spot" "")) | |
633 | (defn (key-binding key t)) | |
634 | key-desc) | |
635 | ;; Handle the case where we faked an entry in "Select and Paste" menu. | |
636 | (if (and (eq defn nil) | |
637 | (stringp (aref key (1- (length key)))) | |
638 | (eq (key-binding (substring key 0 -1)) 'yank-menu)) | |
639 | (setq defn 'menu-bar-select-yank)) | |
640 | ;; Don't bother user with strings from (e.g.) the select-paste menu. | |
641 | (if (stringp (aref key (1- (length key)))) | |
642 | (aset key (1- (length key)) "(any string)")) | |
643 | (if (and (> (length untranslated) 0) | |
644 | (stringp (aref untranslated (1- (length untranslated))))) | |
645 | (aset untranslated (1- (length untranslated)) "(any string)")) | |
646 | ;; Now describe the key, perhaps as changed. | |
647 | (setq key-desc (help-key-description key untranslated)) | |
648 | (if (or (null defn) (integerp defn) (equal defn 'undefined)) | |
649 | (princ (format "%s%s is undefined" key-desc mouse-msg)) | |
650 | (princ (format "%s%s runs the command %S" key-desc mouse-msg defn))))) | |
96ede6b2 | 651 | |
6527c983 EZ |
652 | (defun describe-key (&optional key untranslated up-event) |
653 | "Display documentation of the function invoked by KEY. | |
654 | KEY can be any kind of a key sequence; it can include keyboard events, | |
655 | mouse events, and/or menu events. When calling from a program, | |
656 | pass KEY as a string or a vector. | |
657 | ||
658 | If non-nil, UNTRANSLATED is a vector of the corresponding untranslated events. | |
659 | It can also be a number, in which case the untranslated events from | |
660 | the last key sequence entered are used. | |
661 | UP-EVENT is the up-event that was discarded by reading KEY, or nil. | |
662 | ||
663 | If KEY is a menu item or a tool-bar button that is disabled, this command | |
8ee320fc | 664 | temporarily enables it to allow getting help on disabled items and buttons." |
2c8ed538 RS |
665 | (interactive |
666 | (let ((enable-disabled-menus-and-buttons t) | |
667 | (cursor-in-echo-area t) | |
668 | saved-yank-menu) | |
669 | (unwind-protect | |
670 | (let (key) | |
671 | ;; If yank-menu is empty, populate it temporarily, so that | |
672 | ;; "Select and Paste" menu can generate a complete event. | |
673 | (when (null (cdr yank-menu)) | |
674 | (setq saved-yank-menu (copy-sequence yank-menu)) | |
675 | (menu-bar-update-yank-menu "(any string)" nil)) | |
676 | (setq key (read-key-sequence "Describe key (or click or menu item): ")) | |
677 | (list | |
678 | key | |
679 | (prefix-numeric-value current-prefix-arg) | |
c3f82997 | 680 | ;; If KEY is a down-event, read and include the |
badf89ea RS |
681 | ;; corresponding up-event. Note that there are also |
682 | ;; down-events on scroll bars and mode lines: the actual | |
683 | ;; event then is in the second element of the vector. | |
91a2acb2 | 684 | (and (vectorp key) |
badf89ea RS |
685 | (let ((last-idx (1- (length key)))) |
686 | (and (eventp (aref key last-idx)) | |
687 | (memq 'down (event-modifiers (aref key last-idx))))) | |
91a2acb2 | 688 | (or (and (eventp (aref key 0)) |
98da283b CY |
689 | (memq 'down (event-modifiers (aref key 0))) |
690 | ;; However, for the C-down-mouse-2 popup | |
691 | ;; menu, there is no subsequent up-event. In | |
692 | ;; this case, the up-event is the next | |
693 | ;; element in the supplied vector. | |
694 | (= (length key) 1)) | |
91a2acb2 DK |
695 | (and (> (length key) 1) |
696 | (eventp (aref key 1)) | |
697 | (memq 'down (event-modifiers (aref key 1))))) | |
698 | (read-event)))) | |
2c8ed538 RS |
699 | ;; Put yank-menu back as it was, if we changed it. |
700 | (when saved-yank-menu | |
701 | (setq yank-menu (copy-sequence saved-yank-menu)) | |
702 | (fset 'yank-menu (cons 'keymap yank-menu)))))) | |
02dfca16 SM |
703 | (if (numberp untranslated) |
704 | (setq untranslated (this-single-command-raw-keys))) | |
05ca18a8 KS |
705 | (let* ((event (aref key (if (and (symbolp (aref key 0)) |
706 | (> (length key) 1) | |
707 | (consp (aref key 1))) | |
708 | 1 | |
709 | 0))) | |
91a2acb2 | 710 | (modifiers (event-modifiers event)) |
24a27882 KS |
711 | (mouse-msg (if (or (memq 'click modifiers) (memq 'down modifiers) |
712 | (memq 'drag modifiers)) " at that spot" "")) | |
05ca18a8 KS |
713 | (defn (key-binding key t)) |
714 | defn-up defn-up-tricky ev-type | |
715 | mouse-1-remapped mouse-1-tricky) | |
91a2acb2 | 716 | |
05ca18a8 | 717 | ;; Handle the case where we faked an entry in "Select and Paste" menu. |
24a27882 | 718 | (when (and (eq defn nil) |
91a2acb2 DK |
719 | (stringp (aref key (1- (length key)))) |
720 | (eq (key-binding (substring key 0 -1)) 'yank-menu)) | |
24a27882 KS |
721 | (setq defn 'menu-bar-select-yank)) |
722 | (if (or (null defn) (integerp defn) (equal defn 'undefined)) | |
723 | (message "%s%s is undefined" | |
724 | (help-key-description key untranslated) mouse-msg) | |
32226619 JB |
725 | (help-setup-xref (list #'describe-function defn) |
726 | (called-interactively-p 'interactive)) | |
24a27882 KS |
727 | ;; Don't bother user with strings from (e.g.) the select-paste menu. |
728 | (when (stringp (aref key (1- (length key)))) | |
729 | (aset key (1- (length key)) "(any string)")) | |
730 | (when (and untranslated | |
91a2acb2 | 731 | (stringp (aref untranslated (1- (length untranslated))))) |
24a27882 KS |
732 | (aset untranslated (1- (length untranslated)) |
733 | "(any string)")) | |
734 | ;; Need to do this before erasing *Help* buffer in case event | |
735 | ;; is a mouse click in an existing *Help* buffer. | |
736 | (when up-event | |
737 | (setq ev-type (event-basic-type up-event)) | |
738 | (let ((sequence (vector up-event))) | |
739 | (when (and (eq ev-type 'mouse-1) | |
740 | mouse-1-click-follows-link | |
741 | (not (eq mouse-1-click-follows-link 'double)) | |
742 | (setq mouse-1-remapped | |
743 | (mouse-on-link-p (event-start up-event)))) | |
744 | (setq mouse-1-tricky (and (integerp mouse-1-click-follows-link) | |
745 | (> mouse-1-click-follows-link 0))) | |
746 | (cond ((stringp mouse-1-remapped) | |
747 | (setq sequence mouse-1-remapped)) | |
748 | ((vectorp mouse-1-remapped) | |
749 | (setcar up-event (elt mouse-1-remapped 0))) | |
750 | (t (setcar up-event 'mouse-2)))) | |
751 | (setq defn-up (key-binding sequence nil nil (event-start up-event))) | |
752 | (when mouse-1-tricky | |
753 | (setq sequence (vector up-event)) | |
754 | (aset sequence 0 'mouse-1) | |
755 | (setq defn-up-tricky (key-binding sequence nil nil (event-start up-event)))))) | |
cde56121 | 756 | (with-help-window (help-buffer) |
24a27882 KS |
757 | (princ (help-key-description key untranslated)) |
758 | (princ (format "\ | |
b96817c3 | 759 | %s runs the command %S, which is " |
24a27882 KS |
760 | mouse-msg defn)) |
761 | (describe-function-1 defn) | |
05ca18a8 | 762 | (when up-event |
24a27882 KS |
763 | (unless (or (null defn-up) |
764 | (integerp defn-up) | |
765 | (equal defn-up 'undefined)) | |
766 | (princ (format " | |
767 | ||
768 | ----------------- up-event %s---------------- | |
769 | ||
e8579ebc | 770 | %s%s%s runs the command %S, which is " |
24a27882 | 771 | (if mouse-1-tricky "(short click) " "") |
e8579ebc CY |
772 | (key-description (vector up-event)) |
773 | mouse-msg | |
24a27882 | 774 | (if mouse-1-remapped |
b96817c3 | 775 | " is remapped to <mouse-2>, which" "") |
24a27882 KS |
776 | defn-up)) |
777 | (describe-function-1 defn-up)) | |
778 | (unless (or (null defn-up-tricky) | |
779 | (integerp defn-up-tricky) | |
780 | (eq defn-up-tricky 'undefined)) | |
781 | (princ (format " | |
782 | ||
783 | ----------------- up-event (long click) ---------------- | |
784 | ||
785 | Pressing <%S>%s for longer than %d milli-seconds | |
b96817c3 | 786 | runs the command %S, which is " |
24a27882 KS |
787 | ev-type mouse-msg |
788 | mouse-1-click-follows-link | |
789 | defn-up-tricky)) | |
cde56121 | 790 | (describe-function-1 defn-up-tricky))))))) |
400a1b1f | 791 | \f |
788d62cf MB |
792 | (defun describe-mode (&optional buffer) |
793 | "Display documentation of current major mode and minor modes. | |
efde809a JPW |
794 | A brief summary of the minor modes comes first, followed by the |
795 | major mode description. This is followed by detailed | |
796 | descriptions of the minor modes, each on a separate page. | |
797 | ||
798 | For this to work correctly for a minor mode, the mode's indicator | |
799 | variable \(listed in `minor-mode-alist') must also be a function | |
800 | whose documentation describes the minor mode." | |
f3b5dd74 | 801 | (interactive "@") |
dd39c336 SM |
802 | (unless buffer (setq buffer (current-buffer))) |
803 | (help-setup-xref (list #'describe-mode buffer) | |
32226619 | 804 | (called-interactively-p 'interactive)) |
9639be74 RS |
805 | ;; For the sake of help-do-xref and help-xref-go-back, |
806 | ;; don't switch buffers before calling `help-buffer'. | |
cde56121 | 807 | (with-help-window (help-buffer) |
dd39c336 | 808 | (with-current-buffer buffer |
f6c57ef6 | 809 | (let (minor-modes) |
dd39c336 SM |
810 | ;; Older packages do not register in minor-mode-list but only in |
811 | ;; minor-mode-alist. | |
812 | (dolist (x minor-mode-alist) | |
813 | (setq x (car x)) | |
814 | (unless (memq x minor-mode-list) | |
815 | (push x minor-mode-list))) | |
f6c57ef6 RS |
816 | ;; Find enabled minor mode we will want to mention. |
817 | (dolist (mode minor-mode-list) | |
818 | ;; Document a minor mode if it is listed in minor-mode-alist, | |
819 | ;; non-nil, and has a function definition. | |
af5f4483 SM |
820 | (let ((fmode (or (get mode :minor-mode-function) mode))) |
821 | (and (boundp mode) (symbol-value mode) | |
822 | (fboundp fmode) | |
823 | (let ((pretty-minor-mode | |
824 | (if (string-match "\\(\\(-minor\\)?-mode\\)?\\'" | |
825 | (symbol-name fmode)) | |
826 | (capitalize | |
827 | (substring (symbol-name fmode) | |
828 | 0 (match-beginning 0))) | |
829 | fmode))) | |
830 | (push (list fmode pretty-minor-mode | |
831 | (format-mode-line (assq mode minor-mode-alist))) | |
832 | minor-modes))))) | |
f6c57ef6 RS |
833 | (setq minor-modes |
834 | (sort minor-modes | |
af5f4483 | 835 | (lambda (a b) (string-lessp (cadr a) (cadr b))))) |
f6c57ef6 | 836 | (when minor-modes |
71723367 | 837 | (princ "Enabled minor modes:\n") |
e25e90b4 DP |
838 | (make-local-variable 'help-button-cache) |
839 | (with-current-buffer standard-output | |
840 | (dolist (mode minor-modes) | |
af5f4483 SM |
841 | (let ((mode-function (nth 0 mode)) |
842 | (pretty-minor-mode (nth 1 mode)) | |
e25e90b4 DP |
843 | (indicator (nth 2 mode))) |
844 | (add-text-properties 0 (length pretty-minor-mode) | |
845 | '(face bold) pretty-minor-mode) | |
846 | (save-excursion | |
847 | (goto-char (point-max)) | |
848 | (princ "\n\f\n") | |
849 | (push (point-marker) help-button-cache) | |
850 | ;; Document the minor modes fully. | |
851 | (insert pretty-minor-mode) | |
71723367 RS |
852 | (princ (format " minor mode (%s):\n" |
853 | (if (zerop (length indicator)) | |
854 | "no indicator" | |
855 | (format "indicator%s" | |
d8a869ea | 856 | indicator)))) |
e25e90b4 | 857 | (princ (documentation mode-function))) |
e25e90b4 DP |
858 | (insert-button pretty-minor-mode |
859 | 'action (car help-button-cache) | |
72b64ad5 | 860 | 'follow-link t |
e25e90b4 | 861 | 'help-echo "mouse-2, RET: show full information") |
71723367 RS |
862 | (newline))) |
863 | (forward-line -1) | |
864 | (fill-paragraph nil) | |
865 | (forward-line 1)) | |
866 | ||
867 | (princ "\n(Information about these minor modes follows the major mode info.)\n\n")) | |
f6c57ef6 | 868 | ;; Document the major mode. |
e25e90b4 DP |
869 | (let ((mode mode-name)) |
870 | (with-current-buffer standard-output | |
4e6d3170 | 871 | (let ((start (point))) |
145fe412 | 872 | (insert (format-mode-line mode nil nil buffer)) |
4e6d3170 | 873 | (add-text-properties start (point) '(face bold))))) |
9d05d1ba JB |
874 | (princ " mode") |
875 | (let* ((mode major-mode) | |
876 | (file-name (find-lisp-object-file-name mode nil))) | |
877 | (when file-name | |
878 | (princ (concat " defined in `" (file-name-nondirectory file-name) "'")) | |
879 | ;; Make a hyperlink to the library. | |
880 | (with-current-buffer standard-output | |
881 | (save-excursion | |
882 | (re-search-backward "`\\([^`']+\\)'" nil t) | |
883 | (help-xref-button 1 'help-function-def mode file-name))))) | |
884 | (princ ":\n") | |
309d5b43 | 885 | (princ (documentation major-mode))))) |
6460e534 | 886 | ;; For the sake of IELM and maybe others |
309d5b43 | 887 | nil) |
400a1b1f | 888 | |
f6c57ef6 | 889 | |
8e864068 | 890 | (defun describe-minor-mode (minor-mode) |
335028c3 MY |
891 | "Display documentation of a minor mode given as MINOR-MODE. |
892 | MINOR-MODE can be a minor mode symbol or a minor mode indicator string | |
893 | appeared on the mode-line." | |
7ada28ac | 894 | (interactive (list (completing-read |
335028c3 MY |
895 | "Minor mode: " |
896 | (nconc | |
897 | (describe-minor-mode-completion-table-for-symbol) | |
898 | (describe-minor-mode-completion-table-for-indicator) | |
899 | )))) | |
900 | (if (symbolp minor-mode) | |
901 | (setq minor-mode (symbol-name minor-mode))) | |
902 | (let ((symbols (describe-minor-mode-completion-table-for-symbol)) | |
903 | (indicators (describe-minor-mode-completion-table-for-indicator))) | |
904 | (cond | |
905 | ((member minor-mode symbols) | |
906 | (describe-minor-mode-from-symbol (intern minor-mode))) | |
907 | ((member minor-mode indicators) | |
908 | (describe-minor-mode-from-indicator minor-mode)) | |
909 | (t | |
910 | (error "No such minor mode: %s" minor-mode))))) | |
911 | ||
7ada28ac | 912 | ;; symbol |
335028c3 MY |
913 | (defun describe-minor-mode-completion-table-for-symbol () |
914 | ;; In order to list up all minor modes, minor-mode-list | |
915 | ;; is used here instead of minor-mode-alist. | |
916 | (delq nil (mapcar 'symbol-name minor-mode-list))) | |
917 | (defun describe-minor-mode-from-symbol (symbol) | |
918 | "Display documentation of a minor mode given as a symbol, SYMBOL" | |
7ada28ac | 919 | (interactive (list (intern (completing-read |
335028c3 MY |
920 | "Minor mode symbol: " |
921 | (describe-minor-mode-completion-table-for-symbol))))) | |
922 | (if (fboundp symbol) | |
923 | (describe-function symbol) | |
924 | (describe-variable symbol))) | |
925 | ||
926 | ;; indicator | |
927 | (defun describe-minor-mode-completion-table-for-indicator () | |
7ada28ac | 928 | (delq nil |
335028c3 MY |
929 | (mapcar (lambda (x) |
930 | (let ((i (format-mode-line x))) | |
931 | ;; remove first space if existed | |
932 | (cond | |
933 | ((= 0 (length i)) | |
934 | nil) | |
94318c8a | 935 | ((eq (aref i 0) ?\s) |
335028c3 | 936 | (substring i 1)) |
7ada28ac | 937 | (t |
335028c3 MY |
938 | i)))) |
939 | minor-mode-alist))) | |
8e864068 | 940 | (defun describe-minor-mode-from-indicator (indicator) |
335028c3 MY |
941 | "Display documentation of a minor mode specified by INDICATOR. |
942 | If you call this function interactively, you can give indicator which | |
943 | is currently activated with completion." | |
7ada28ac LT |
944 | (interactive (list |
945 | (completing-read | |
8e864068 | 946 | "Minor mode indicator: " |
335028c3 | 947 | (describe-minor-mode-completion-table-for-indicator)))) |
8e864068 JB |
948 | (let ((minor-mode (lookup-minor-mode-from-indicator indicator))) |
949 | (if minor-mode | |
335028c3 | 950 | (describe-minor-mode-from-symbol minor-mode) |
8e864068 JB |
951 | (error "Cannot find minor mode for `%s'" indicator)))) |
952 | ||
953 | (defun lookup-minor-mode-from-indicator (indicator) | |
954 | "Return a minor mode symbol from its indicator on the modeline." | |
335028c3 | 955 | ;; remove first space if existed |
7ada28ac | 956 | (if (and (< 0 (length indicator)) |
94318c8a | 957 | (eq (aref indicator 0) ?\s)) |
335028c3 | 958 | (setq indicator (substring indicator 1))) |
8e864068 JB |
959 | (let ((minor-modes minor-mode-alist) |
960 | result) | |
961 | (while minor-modes | |
962 | (let* ((minor-mode (car (car minor-modes))) | |
7ada28ac | 963 | (anindicator (format-mode-line |
335028c3 MY |
964 | (car (cdr (car minor-modes)))))) |
965 | ;; remove first space if existed | |
7ada28ac | 966 | (if (and (stringp anindicator) |
335028c3 | 967 | (> (length anindicator) 0) |
94318c8a | 968 | (eq (aref anindicator 0) ?\s)) |
335028c3 MY |
969 | (setq anindicator (substring anindicator 1))) |
970 | (if (equal indicator anindicator) | |
8e864068 JB |
971 | (setq result minor-mode |
972 | minor-modes nil) | |
973 | (setq minor-modes (cdr minor-modes))))) | |
974 | result)) | |
975 | ||
48ce3c22 RS |
976 | \f |
977 | ;;; Automatic resizing of temporary buffers. | |
978 | ||
4483ddc5 | 979 | (defcustom temp-buffer-max-height (lambda (buffer) (/ (- (frame-height) 2) 2)) |
4e6d3170 | 980 | "Maximum height of a window displaying a temporary buffer. |
90e357ae RS |
981 | This is effective only when Temp Buffer Resize mode is enabled. |
982 | The value is the maximum height (in lines) which `resize-temp-buffer-window' | |
48ce3c22 | 983 | will give to a window displaying a temporary buffer. |
90e357ae RS |
984 | It can also be a function to be called to choose the height for such a buffer. |
985 | It gets one argumemt, the buffer, and should return a positive integer." | |
48ce3c22 RS |
986 | :type '(choice integer function) |
987 | :group 'help | |
988 | :version "20.4") | |
989 | ||
4e1ede6c SM |
990 | (define-minor-mode temp-buffer-resize-mode |
991 | "Toggle the mode which makes windows smaller for temporary buffers. | |
48ce3c22 RS |
992 | With prefix argument ARG, turn the resizing of windows displaying temporary |
993 | buffers on if ARG is positive or off otherwise. | |
4e1ede6c SM |
994 | This makes the window the right height for its contents, but never |
995 | more than `temp-buffer-max-height' nor less than `window-min-height'. | |
996 | This applies to `help', `apropos' and `completion' buffers, and some others." | |
b0fbf754 | 997 | :global t :group 'help |
4e1ede6c | 998 | (if temp-buffer-resize-mode |
57f43907 | 999 | ;; `help-make-xrefs' may add a `back' button and thus increase the |
4e1ede6c SM |
1000 | ;; text size, so `resize-temp-buffer-window' must be run *after* it. |
1001 | (add-hook 'temp-buffer-show-hook 'resize-temp-buffer-window 'append) | |
8304a3bb | 1002 | (remove-hook 'temp-buffer-show-hook 'resize-temp-buffer-window))) |
48ce3c22 RS |
1003 | |
1004 | (defun resize-temp-buffer-window () | |
2a5f11a2 | 1005 | "Resize the selected window to fit its contents. |
4483ddc5 | 1006 | Will not make it higher than `temp-buffer-max-height' nor smaller than |
b2c85790 | 1007 | `window-min-height'. Do nothing if it is the only window on its frame, if it |
48ce3c22 RS |
1008 | is not as wide as the frame or if some of the window's contents are scrolled |
1009 | out of view." | |
1010 | (unless (or (one-window-p 'nomini) | |
1011 | (not (pos-visible-in-window-p (point-min))) | |
2a5f11a2 | 1012 | (not (window-full-width-p))) |
d9c30bdf MB |
1013 | (fit-window-to-buffer |
1014 | (selected-window) | |
1015 | (if (functionp temp-buffer-max-height) | |
1016 | (funcall temp-buffer-max-height (current-buffer)) | |
1017 | temp-buffer-max-height)))) | |
48ce3c22 | 1018 | |
172892e3 | 1019 | \f |
cde56121 MR |
1020 | ;;; help-window |
1021 | ||
1022 | (defcustom help-window-select 'other | |
1023 | "Non-nil means select help window for viewing. | |
1024 | Choices are: | |
1025 | never (nil) Select help window only if there is no other window | |
1026 | on its frame. | |
1027 | other Select help window unless the selected window is the | |
1028 | only other window on its frame. | |
1029 | always (t) Always select the help window. | |
1030 | ||
1031 | This option has effect if and only if the help window was created | |
1032 | by `with-help-window'" | |
1033 | :type '(choice (const :tag "never (nil)" nil) | |
1034 | (const :tag "other" other) | |
1035 | (const :tag "always (t)" t)) | |
1036 | :group 'help | |
1037 | :version "23.1") | |
1038 | ||
1039 | (defun help-window-display-message (quit-part window &optional other) | |
1040 | "Display message telling how to quit and scroll help window. | |
1041 | QUIT-PART is a string telling how to quit the help window WINDOW. | |
1042 | Optional argument OTHER non-nil means return text telling how to | |
1043 | scroll the \"other\" window." | |
1044 | (let ((scroll-part | |
1045 | (cond | |
1046 | ((pos-visible-in-window-p | |
1047 | (with-current-buffer (window-buffer window) | |
1048 | (point-max)) window) | |
1049 | ;; Buffer end is visible. | |
1050 | ".") | |
1051 | (other ", \\[scroll-other-window] to scroll help.") | |
1052 | (t ", \\[scroll-up] to scroll help.")))) | |
f6e7ec02 | 1053 | (message "%s" |
cde56121 MR |
1054 | (substitute-command-keys (concat quit-part scroll-part))))) |
1055 | ||
1056 | (defun help-window-setup-finish (window &optional reuse keep-frame) | |
1057 | "Finish setting up help window WINDOW. | |
1058 | Select WINDOW according to the value of `help-window-select'. | |
1059 | Display message telling how to scroll and eventually quit WINDOW. | |
1060 | ||
6baa27a2 CY |
1061 | Optional argument REUSE non-nil means WINDOW has been reused by |
1062 | `display-buffer'. Optional argument KEEP-FRAME non-nil means | |
1063 | that quitting should not delete WINDOW's frame." | |
cde56121 MR |
1064 | (let ((number-of-windows |
1065 | (length (window-list (window-frame window) 'no-mini window)))) | |
1066 | (cond | |
1067 | ((eq window (selected-window)) | |
1068 | ;; The help window is the selected window, probably the | |
1069 | ;; `pop-up-windows' nil case. | |
1070 | (help-window-display-message | |
1071 | (if reuse | |
1072 | "Type \"q\" to restore this window" | |
1073 | ;; This should not be taken. | |
1074 | "Type \"q\" to quit") window)) | |
1075 | ((= number-of-windows 1) | |
1076 | ;; The help window is alone on a frame and not the selected | |
1077 | ;; window, could be the `pop-up-frames' t case. | |
1078 | (help-window-display-message | |
1079 | (cond | |
1080 | (keep-frame "Type \"q\" to delete this window") | |
1081 | (reuse "Type \"q\" to restore this window") | |
1082 | (view-remove-frame-by-deleting "Type \"q\" to delete this frame") | |
1083 | (t "Type \"q\" to iconify this frame")) | |
1084 | window)) | |
1085 | ((and (= number-of-windows 2) | |
1086 | (eq (window-frame window) (window-frame (selected-window)))) | |
1087 | ;; There are two windows on the help window's frame and the other | |
1088 | ;; window is the selected one. | |
1089 | (if (memq help-window-select '(nil other)) | |
1090 | ;; Do not select the help window. | |
1091 | (help-window-display-message | |
1092 | (if reuse | |
1093 | ;; Offer `display-buffer' for consistency with | |
b3d8e4a0 | 1094 | ;; `help-print-return-message'. This is hardly TRT when |
cde56121 MR |
1095 | ;; the other window and the selected window display the |
1096 | ;; same buffer but has been handled this way ever since. | |
1097 | "Type \\[display-buffer] RET to restore the other window" | |
1098 | ;; The classic "two windows" configuration. | |
1099 | "Type \\[delete-other-windows] to delete the help window") | |
1100 | window t) | |
1101 | ;; Select help window and tell how to quit. | |
1102 | (select-window window) | |
1103 | (help-window-display-message | |
1104 | (if reuse | |
1105 | "Type \"q\" to restore this window" | |
1106 | "Type \"q\" to delete this window") window))) | |
1107 | (help-window-select | |
1108 | ;; Issuing a message with 3 or more windows on the same frame | |
1109 | ;; without selecting the help window doesn't make any sense. | |
1110 | (select-window window) | |
1111 | (help-window-display-message | |
1112 | (if reuse | |
1113 | "Type \"q\" to restore this window" | |
1114 | "Type \"q\" to delete this window") window))))) | |
1115 | ||
1116 | (defun help-window-setup (list-of-frames list-of-window-tuples) | |
1117 | "Set up help window. | |
1118 | LIST-OF-FRAMES and LIST-OF-WINDOW-TUPLES are the lists of frames | |
1119 | and window quadruples built by `with-help-window'. The help | |
1120 | window itself is specified by the variable `help-window'." | |
1121 | (let* ((help-buffer (window-buffer help-window)) | |
1122 | ;; `help-buffer' now denotes the help window's buffer. | |
1123 | (view-entry | |
1124 | (assq help-window | |
1125 | (buffer-local-value 'view-return-to-alist help-buffer))) | |
1126 | (help-entry (assq help-window list-of-window-tuples))) | |
1127 | ||
1128 | ;; Handle `help-window-point-marker'. | |
1129 | (when (eq (marker-buffer help-window-point-marker) help-buffer) | |
1130 | (set-window-point help-window help-window-point-marker) | |
1131 | ;; Reset `help-window-point-marker'. | |
1132 | (set-marker help-window-point-marker nil)) | |
1133 | ||
1134 | (cond | |
1135 | (view-entry | |
1136 | ;; `view-return-to-alist' has an entry for the help window. | |
1137 | (cond | |
1138 | ((eq help-window (selected-window)) | |
1139 | ;; The help window is the selected window, probably because the | |
1140 | ;; user followed a backward/forward button or a cross reference. | |
1141 | ;; In this case just purge stale entries from | |
1142 | ;; `view-return-to-alist' but leave the entry alone and don't | |
1143 | ;; display a message. | |
1144 | (view-return-to-alist-update help-buffer)) | |
1145 | ((and help-entry (eq (cadr help-entry) help-buffer)) | |
1146 | ;; The help window was not selected but displayed the help | |
1147 | ;; buffer. In this case reuse existing exit information but try | |
1148 | ;; to get back to the selected window when quitting. Don't | |
1149 | ;; display a message since the user must have seen one before. | |
1150 | (view-return-to-alist-update | |
1151 | help-buffer (cons help-window | |
1152 | (cons (selected-window) (cddr view-entry))))) | |
1153 | (help-entry | |
1154 | ;; The help window was not selected, did display the help buffer | |
1155 | ;; earlier, but displayed another buffer when help was invoked. | |
1156 | ;; Set up things so that quitting will show that buffer again. | |
1157 | (view-return-to-alist-update | |
1158 | help-buffer (cons help-window | |
1159 | (cons (selected-window) (cdr help-entry)))) | |
1160 | (help-window-setup-finish help-window t)) | |
1161 | (t | |
1162 | ;; The help window is new but `view-return-to-alist' had an | |
1163 | ;; entry for it. This should never happen. | |
1164 | (view-return-to-alist-update | |
1165 | help-buffer (cons help-window | |
1166 | (cons (selected-window) 'quit-window))) | |
1167 | (help-window-setup-finish help-window t)))) | |
1168 | (help-entry | |
1169 | ;; `view-return-to-alist' does not have an entry for help window | |
1170 | ;; but `list-of-window-tuples' does. Hence `display-buffer' must | |
1171 | ;; have reused an existing window. | |
1172 | (if (eq (cadr help-entry) help-buffer) | |
1173 | ;; The help window displayed `help-buffer' before but no | |
1174 | ;; `view-return-to-alist' entry was found probably because the | |
1175 | ;; user manually switched to the help buffer. Set up things | |
1176 | ;; for `quit-window' although `view-exit-action' should be | |
1177 | ;; able to handle this case all by itself. | |
1178 | (progn | |
1179 | (view-return-to-alist-update | |
1180 | help-buffer (cons help-window | |
1181 | (cons (selected-window) 'quit-window))) | |
1182 | (help-window-setup-finish help-window t)) | |
1183 | ;; The help window displayed another buffer before. Set up | |
1184 | ;; things in a way that quitting can orderly show that buffer | |
1185 | ;; again. The window-start and window-point information from | |
1186 | ;; `list-of-window-tuples' provide the necessary information. | |
1187 | (view-return-to-alist-update | |
1188 | help-buffer (cons help-window | |
1189 | (cons (selected-window) (cdr help-entry)))) | |
1190 | (help-window-setup-finish help-window t))) | |
1191 | ((memq (window-frame help-window) list-of-frames) | |
1192 | ;; The help window is a new window on an existing frame. This | |
1193 | ;; case must be handled specially by `help-window-setup-finish' | |
1194 | ;; and `view-mode-exit' to ascertain that quitting does _not_ | |
1195 | ;; inadvertently delete the frame. | |
1196 | (view-return-to-alist-update | |
1197 | help-buffer (cons help-window | |
1198 | (cons (selected-window) 'keep-frame))) | |
1199 | (help-window-setup-finish help-window nil t)) | |
1200 | (t | |
1201 | ;; The help window is shown on a new frame. In this case quitting | |
1202 | ;; shall handle both, the help window _and_ its frame. We changed | |
1203 | ;; the default of `view-remove-frame-by-deleting' to t in order to | |
1204 | ;; intuitively DTRT here. | |
1205 | (view-return-to-alist-update | |
1206 | help-buffer (cons help-window (cons (selected-window) t))) | |
1207 | (help-window-setup-finish help-window))))) | |
1208 | ||
1209 | ;; `with-help-window' is a wrapper for `with-output-to-temp-buffer' | |
1210 | ;; providing the following additional twists: | |
1211 | ||
1212 | ;; (1) Issue more accurate messages telling how to scroll and quit the | |
1213 | ;; help window. | |
1214 | ||
1215 | ;; (2) Make `view-mode-exit' DTRT in more cases. | |
1216 | ||
1217 | ;; (3) An option (customizable via `help-window-select') to select the | |
1218 | ;; help window automatically. | |
1219 | ||
1220 | ;; (4) A marker (`help-window-point-marker') to move point in the help | |
1221 | ;; window to an arbitrary buffer position. | |
1222 | ||
b3d8e4a0 | 1223 | ;; Note: It's usually always wrong to use `help-print-return-message' in |
cde56121 MR |
1224 | ;; the body of `with-help-window'. |
1225 | (defmacro with-help-window (buffer-name &rest body) | |
1226 | "Display buffer BUFFER-NAME in a help window evaluating BODY. | |
1227 | Select help window if the actual value of the user option | |
eff26424 | 1228 | `help-window-select' says so. Return last value in BODY." |
cde56121 MR |
1229 | (declare (indent 1) (debug t)) |
1230 | ;; Bind list-of-frames to `frame-list' and list-of-window-tuples to a | |
1231 | ;; list of one <window window-buffer window-start window-point> tuple | |
1232 | ;; for each live window. | |
1233 | `(let ((list-of-frames (frame-list)) | |
1234 | (list-of-window-tuples | |
1235 | (let (list) | |
1236 | (walk-windows | |
1237 | (lambda (window) | |
1238 | (push (list window (window-buffer window) | |
1239 | (window-start window) (window-point window)) | |
1240 | list)) | |
1241 | 'no-mini t) | |
1242 | list))) | |
eff26424 MR |
1243 | ;; Make `help-window' t to trigger `help-mode-finish' to set |
1244 | ;; `help-window' to the actual help window. | |
cde56121 MR |
1245 | (setq help-window t) |
1246 | ;; Make `help-window-point-marker' point nowhere (the only place | |
1247 | ;; where this should be set to a buffer position is within BODY). | |
1248 | (set-marker help-window-point-marker nil) | |
eff26424 MR |
1249 | (prog1 |
1250 | ;; Return value returned by `with-output-to-temp-buffer'. | |
1251 | (with-output-to-temp-buffer ,buffer-name | |
1252 | (progn ,@body)) | |
1253 | (when (windowp help-window) | |
1254 | ;; Set up help window. | |
1255 | (help-window-setup list-of-frames list-of-window-tuples)) | |
1256 | ;; Reset `help-window' to nil to avoid confusing future calls of | |
1257 | ;; `help-mode-finish' with plain `with-output-to-temp-buffer'. | |
1258 | (setq help-window nil)))) | |
cbb59342 CY |
1259 | |
1260 | ;; Called from C, on encountering `help-char' when reading a char. | |
1261 | ;; Don't print to *Help*; that would clobber Help history. | |
1262 | (defun help-form-show () | |
1263 | "Display the output of a non-nil `help-form'." | |
1264 | (let ((msg (eval help-form))) | |
1265 | (if (stringp msg) | |
1266 | (with-output-to-temp-buffer " *Char Help*" | |
1267 | (princ msg))))) | |
cde56121 | 1268 | \f |
172892e3 JB |
1269 | (provide 'help) |
1270 | ||
1a06eabd | 1271 | ;;; help.el ends here |