Mercurial > hg > xemacs-beta

comparison lisp/apropos.el @ 217:d44af0c54775 r20-4b7

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Import from CVS: tag r20-4b7
author cvs
date Mon, 13 Aug 2007 10:08:34 +0200
parents
children c5d627a313b1
comparison
equal deleted inserted replaced
216:43306a74e31c 217:d44af0c54775
1 ;;; apropos.el --- apropos commands for users and programmers.
2
3 ;; Copyright (C) 1989, 1994, 1995 Free Software Foundation, Inc.
4
5 ;; Author: Joe Wells <jbw@bigbird.bu.edu>
6 ;; Rewritten: Daniel.Pfeiffer@Informatik.START.dbp.de, fax (+49 69) 7588-2389
7 ;; Keywords: help
8
9 ;; This file is part of XEmacs.
10
11 ;; XEmacs is free software; you can redistribute it and/or modify it
12 ;; under the terms of the GNU General Public License as published by
13 ;; the Free Software Foundation; either version 2, or (at your option)
14 ;; any later version.
15
16 ;; XEmacs is distributed in the hope that it will be useful, but
17 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 ;; General Public License for more details.
20
21 ;; You should have received a copy of the GNU General Public License
22 ;; along with GNU Emacs; see the file COPYING. If not, write to the
23 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
24 ;; Boston, MA 02111-1307, USA.
25
26 ;;; Synched up with: FSF 19.34.
27
28 ;;; Commentary:
29
30 ;; The ideas for this package were derived from the C code in
31 ;; src/keymap.c and elsewhere. The functions in this file should
32 ;; always be byte-compiled for speed. Someone should rewrite this in
33 ;; C (as part of src/keymap.c) for speed.
34
35 ;; The idea for super-apropos is based on the original implementation
36 ;; by Lynn Slater <lrs@esl.com>.
37
38 ;; History:
39 ;; Fixed bug, current-local-map can return nil.
40 ;; Change, doesn't calculate key-bindings unless needed.
41 ;; Added super-apropos capability, changed print functions.
42 ;;; Made fast-apropos and super-apropos share code.
43 ;;; Sped up fast-apropos again.
44 ;; Added apropos-do-all option.
45 ;;; Added fast-command-apropos.
46 ;; Changed doc strings to comments for helping functions.
47 ;;; Made doc file buffer read-only, buried it.
48 ;; Only call substitute-command-keys if do-all set.
49
50 ;; Optionally use configurable faces to make the output more legible.
51 ;; Differentiate between command, function and macro.
52 ;; Apropos-command (ex command-apropos) does cmd and optionally user var.
53 ;; Apropos shows all 3 aspects of symbols (fn, var and plist)
54 ;; Apropos-documentation (ex super-apropos) now finds all it should.
55 ;; New apropos-value snoops through all values and optionally plists.
56 ;; Reading DOC file doesn't load nroff.
57 ;; Added hypertext following of documentation, mouse-2 on variable gives value
58 ;; from buffer in active window.
59
60 ;;; Code:
61
62 ;; I see a degradation of maybe 10-20% only.
63 ;; [sb -- FSF protects the face declarations with `if window-system'
64 ;; I see no reason why we should do so]
65 (defvar apropos-do-all nil
66 "*Whether the apropos commands should do more.
67 Slows them down more or less. Set this non-nil if you have a fast machine.")
68
69 ;; XEmacs addition
70 (defvar apropos-symbol-face (if (boundp 'font-lock-keyword-face)
71 font-lock-keyword-face
72 'bold)
73 "*Face for symbol name in apropos output or `nil'.
74 This looks good, but slows down the commands several times.")
75
76 ;; XEmacs addition
77 (defvar apropos-keybinding-face (if (boundp 'font-lock-string-face)
78 font-lock-string-face
79 'underline)
80 "*Face for keybinding display in apropos output or `nil'.
81 This looks good, but slows down the commands several times.")
82
83 ;; XEmacs addition
84 (defvar apropos-label-face (if (boundp 'font-lock-comment-face)
85 font-lock-comment-face
86 'italic)
87 "*Face for label (Command, Variable ...) in apropos output or `nil'.
88 If this is `nil' no mouse highlighting occurs.
89 This looks good, but slows down the commands several times.
90 When this is a face name, as it is initially, it gets transformed to a
91 text-property list for efficiency.")
92
93 ;; XEmacs addition
94 (defvar apropos-property-face (if (boundp 'font-lock-variable-name-face)
95 font-lock-variable-name-face
96 'bold-italic)
97 "*Face for property name in apropos output or `nil'.
98 This looks good, but slows down the commands several times.")
99
100 (defvar apropos-match-face 'secondary-selection
101 "*Face for matching part in apropos-documentation/value output or `nil'.
102 This looks good, but slows down the commands several times.")
103
104
105 (defvar apropos-mode-map
106 (let ((map (make-sparse-keymap)))
107 (define-key map [(control m)] 'apropos-follow)
108 (define-key map [(button2up)] 'apropos-mouse-follow)
109 (define-key map [(button2)] 'undefined)
110 map)
111 "Keymap used in Apropos mode.")
112
113
114 (defvar apropos-regexp nil
115 "Regexp used in current apropos run.")
116
117 (defvar apropos-files-scanned ()
118 "List of elc files already scanned in current run of `apropos-documentation'.")
119
120 (defvar apropos-accumulator ()
121 "Alist of symbols already found in current apropos run.")
122
123 (defvar apropos-item ()
124 "Current item in or for apropos-accumulator.")
125
126 (defvar apropos-mode-hook nil) ; XEmacs
127
128 (defun apropos-mode ()
129 "Major mode for following hyperlinks in output of apropos commands.
130
131 \\{apropos-mode-map}"
132 (interactive)
133 (kill-all-local-variables)
134 (use-local-map apropos-mode-map)
135 (setq major-mode 'apropos-mode
136 mode-name "Apropos")
137 (run-hooks 'apropos-mode-hook)) ; XEmacs
138
139
140 ;; For auld lang syne:
141 ;;;###autoload
142 (fset 'command-apropos 'apropos-command)
143 ;;;###autoload
144 (defun apropos-command (apropos-regexp &optional do-all)
145 "Shows commands (interactively callable functions) that match REGEXP.
146 With optional prefix ARG or if `apropos-do-all' is non-nil, also show
147 variables."
148 (interactive (list (read-string (concat "Apropos command "
149 (if (or current-prefix-arg
150 apropos-do-all)
151 "or variable ")
152 "(regexp): "))
153 current-prefix-arg))
154 (let ((message
155 (let ((standard-output (get-buffer-create "*Apropos*")))
156 (print-help-return-message 'identity))))
157 (or do-all (setq do-all apropos-do-all))
158 (setq apropos-accumulator
159 (apropos-internal apropos-regexp
160 (if do-all
161 (lambda (symbol) (or (commandp symbol)
162 (user-variable-p symbol)))
163 'commandp)))
164 (if (apropos-print
165 t
166 (lambda (p)
167 (let (doc symbol)
168 (while p
169 (setcar p (list
170 (setq symbol (car p))
171 (if (commandp symbol)
172 (if (setq doc
173 ;; XEmacs change: if obsolete,
174 ;; only mention that.
175 (or (function-obsoleteness-doc symbol)
176 (documentation symbol t)))
177 (substring doc 0 (string-match "\n" doc))
178 "(not documented)"))
179 (and do-all
180 (user-variable-p symbol)
181 (if (setq doc
182 (or
183 ;; XEmacs change: if obsolete,
184 ;; only mention that.
185 (variable-obsoleteness-doc symbol)
186 (documentation-property
187 symbol 'variable-documentation t)))
188 (substring doc 0
189 (string-match "\n" doc))))))
190 (setq p (cdr p)))))
191 nil)
192 (and message (message message)))))
193
194
195 ;;;###autoload
196 (defun apropos (apropos-regexp &optional do-all)
197 "Show all bound symbols whose names match REGEXP.
198 With optional prefix ARG or if `apropos-do-all' is non-nil, also show unbound
199 symbols and key bindings, which is a little more time-consuming.
200 Returns list of symbols and documentation found."
201 (interactive "sApropos symbol (regexp): \nP")
202 ;; XEmacs change: hitting ENTER by mistake is a common mess-up and
203 ;; shouldn't make Emacs hang for a long time trying to list all symbols.
204 (or (> (length apropos-regexp) 0)
205 (error "Must pass non-empty regexp to `apropos'"))
206 (setq apropos-accumulator
207 (apropos-internal apropos-regexp
208 (and (not do-all)
209 (not apropos-do-all)
210 (lambda (symbol)
211 (or (fboundp symbol)
212 (boundp symbol)
213 (find-face symbol)
214 (symbol-plist symbol))))))
215 (apropos-print
216 (or do-all apropos-do-all)
217 (lambda (p)
218 (let (symbol doc)
219 (while p
220 (setcar p (list
221 (setq symbol (car p))
222 (if (fboundp symbol)
223 (if (setq doc
224 ;; XEmacs change: if obsolete,
225 ;; only mention that.
226 (or (function-obsoleteness-doc symbol)
227 (documentation symbol t)))
228 (substring doc 0 (string-match "\n" doc))
229 "(not documented)"))
230 (if (boundp symbol)
231 (if (setq doc
232 (or
233 ;; XEmacs change: if obsolete,
234 ;; only mention that.
235 (variable-obsoleteness-doc symbol)
236 (documentation-property
237 symbol 'variable-documentation t)))
238 (substring doc 0
239 (string-match "\n" doc))
240 "(not documented)"))
241 (if (setq doc (symbol-plist symbol))
242 (if (eq (/ (length doc) 2) 1)
243 (format "1 property (%s)" (car doc))
244 (concat (/ (length doc) 2) " properties")))
245 (if (get symbol 'widget-type)
246 (if (setq doc (documentation-property
247 symbol 'widget-documentation t))
248 (substring doc 0
249 (string-match "\n" doc))
250 "(not documented)"))
251 (if (find-face symbol)
252 (if (setq doc (face-doc-string symbol))
253 (substring doc 0
254 (string-match "\n" doc))
255 "(not documented)"))
256 (when (get symbol 'custom-group)
257 (if (setq doc (documentation-property
258 symbol 'group-documentation t))
259 (substring doc 0
260 (string-match "\n" doc))
261 "(not documented)"))))
262 (setq p (cdr p)))))
263 nil))
264
265
266 ;;;###autoload
267 (defun apropos-value (apropos-regexp &optional do-all)
268 "Show all symbols whose value's printed image matches REGEXP.
269 With optional prefix ARG or if `apropos-do-all' is non-nil, also looks
270 at the function and at the names and values of properties.
271 Returns list of symbols and values found."
272 (interactive "sApropos value (regexp): \nP")
273 (or do-all (setq do-all apropos-do-all))
274 (setq apropos-accumulator ())
275 (let (f v p)
276 (mapatoms
277 (lambda (symbol)
278 (setq f nil v nil p nil)
279 (or (memq symbol '(apropos-regexp do-all apropos-accumulator
280 symbol f v p))
281 (setq v (apropos-value-internal 'boundp symbol 'symbol-value)))
282 (if do-all
283 (setq f (apropos-value-internal 'fboundp symbol 'symbol-function)
284 p (apropos-format-plist symbol "\n " t)))
285 (if (or f v p)
286 (setq apropos-accumulator (cons (list symbol f v p)
287 apropos-accumulator))))))
288 (apropos-print nil nil t))
289
290
291 ;;;###autoload
292 (defun apropos-documentation (apropos-regexp &optional do-all)
293 "Show symbols whose documentation contain matches for REGEXP.
294 With optional prefix ARG or if `apropos-do-all' is non-nil, also use
295 documentation that is not stored in the documentation file and show key
296 bindings.
297 Returns list of symbols and documentation found."
298 (interactive "sApropos documentation (regexp): \nP")
299 (or do-all (setq do-all apropos-do-all))
300 (setq apropos-accumulator () apropos-files-scanned ())
301 (let ((standard-input (get-buffer-create " apropos-temp"))
302 f v)
303 (unwind-protect
304 (save-excursion
305 (set-buffer standard-input)
306 (apropos-documentation-check-doc-file)
307 (if do-all
308 (mapatoms
309 (lambda (symbol)
310 (setq f (apropos-safe-documentation symbol)
311 v (get symbol 'variable-documentation))
312 (if (integerp v) (setq v))
313 (setq f (apropos-documentation-internal f)
314 v (apropos-documentation-internal v))
315 (if (or f v)
316 (if (setq apropos-item
317 (cdr (assq symbol apropos-accumulator)))
318 (progn
319 (if f
320 (setcar apropos-item f))
321 (if v
322 (setcar (cdr apropos-item) v)))
323 (setq apropos-accumulator
324 (cons (list symbol f v)
325 apropos-accumulator)))))))
326 (apropos-print nil nil t))
327 (kill-buffer standard-input))))
328
329
330 (defun apropos-value-internal (predicate symbol function)
331 (if (funcall predicate symbol)
332 (progn
333 (setq symbol (prin1-to-string (funcall function symbol)))
334 (if (string-match apropos-regexp symbol)
335 (progn
336 (if apropos-match-face
337 (put-text-property (match-beginning 0) (match-end 0)
338 'face apropos-match-face
339 symbol))
340 symbol)))))
341
342 (defun apropos-documentation-internal (doc)
343 (if (consp doc)
344 (apropos-documentation-check-elc-file (car doc))
345 (and doc
346 (string-match apropos-regexp doc)
347 (progn
348 (if apropos-match-face
349 (put-text-property (match-beginning 0)
350 (match-end 0)
351 'face apropos-match-face
352 (setq doc (copy-sequence doc))))
353 doc))))
354
355 (defun apropos-format-plist (pl sep &optional compare)
356 (setq pl (symbol-plist pl))
357 (let (p p-out)
358 (while pl
359 (setq p (format "%s %S" (car pl) (nth 1 pl)))
360 (if (or (not compare) (string-match apropos-regexp p))
361 (if apropos-property-face
362 (put-text-property 0 (length (symbol-name (car pl)))
363 'face apropos-property-face p))
364 (setq p nil))
365 (if p
366 (progn
367 (and compare apropos-match-face
368 (put-text-property (match-beginning 0) (match-end 0)
369 'face apropos-match-face
370 p))
371 (setq p-out (concat p-out (if p-out sep) p))))
372 (setq pl (nthcdr 2 pl)))
373 p-out))
374
375
376 ;; Finds all documentation related to APROPOS-REGEXP in internal-doc-file-name.
377
378 (defun apropos-documentation-check-doc-file ()
379 (let (type symbol (sepa 2) sepb beg end)
380 (insert ?\^_)
381 (backward-char)
382 (insert-file-contents (concat doc-directory internal-doc-file-name))
383 (forward-char)
384 (while (save-excursion
385 (setq sepb (search-forward "\^_"))
386 (not (eobp)))
387 (beginning-of-line 2)
388 (if (save-restriction
389 (narrow-to-region (point) (1- sepb))
390 (re-search-forward apropos-regexp nil t))
391 (progn
392 (setq beg (match-beginning 0)
393 end (point))
394 (goto-char (1+ sepa))
395 (or (setq type (if (eq ?F (preceding-char))
396 1 ; function documentation
397 2) ; variable documentation
398 symbol (read)
399 beg (- beg (point) 1)
400 end (- end (point) 1)
401 doc (buffer-substring (1+ (point)) (1- sepb))
402 apropos-item (assq symbol apropos-accumulator))
403 (setq apropos-item (list symbol nil nil)
404 apropos-accumulator (cons apropos-item
405 apropos-accumulator)))
406 (if apropos-match-face
407 (put-text-property beg end 'face apropos-match-face doc))
408 (setcar (nthcdr type apropos-item) doc)))
409 (setq sepa (goto-char sepb)))))
410
411 (defun apropos-documentation-check-elc-file (file)
412 (if (member file apropos-files-scanned)
413 nil
414 (let (symbol doc beg end this-is-a-variable)
415 (setq apropos-files-scanned (cons file apropos-files-scanned))
416 (erase-buffer)
417 (insert-file-contents file)
418 (while (search-forward "\n#@" nil t)
419 ;; Read the comment length, and advance over it.
420 (setq end (read)
421 beg (1+ (point))
422 end (+ (point) end -1))
423 (forward-char)
424 (if (save-restriction
425 ;; match ^ and $ relative to doc string
426 (narrow-to-region beg end)
427 (re-search-forward apropos-regexp nil t))
428 (progn
429 (goto-char (+ end 2))
430 (setq doc (buffer-substring beg end)
431 end (- (match-end 0) beg)
432 beg (- (match-beginning 0) beg)
433 this-is-a-variable (looking-at "(def\\(var\\|const\\) ")
434 symbol (progn
435 (skip-chars-forward "(a-z")
436 (forward-char)
437 (read))
438 symbol (if (consp symbol)
439 (nth 1 symbol)
440 symbol))
441 (if (if this-is-a-variable
442 (get symbol 'variable-documentation)
443 (and (fboundp symbol) (apropos-safe-documentation symbol)))
444 (progn
445 (or (setq apropos-item (assq symbol apropos-accumulator))
446 (setq apropos-item (list symbol nil nil)
447 apropos-accumulator (cons apropos-item
448 apropos-accumulator)))
449 (if apropos-match-face
450 (put-text-property beg end 'face apropos-match-face
451 doc))
452 (setcar (nthcdr (if this-is-a-variable 2 1)
453 apropos-item)
454 doc)))))))))
455
456
457
458 (defun apropos-safe-documentation (function)
459 "Like documentation, except it avoids calling `get_doc_string'.
460 Will return nil instead."
461 (while (and function (symbolp function))
462 (setq function (if (fboundp function)
463 (symbol-function function))))
464 (if (eq (car-safe function) 'macro)
465 (setq function (cdr function)))
466 ;; XEmacs change from: (setq function (if (byte-code-function-p function)
467 (setq function (if (compiled-function-p function)
468 (if (fboundp 'compiled-function-doc-string)
469 (compiled-function-doc-string function)
470 (if (> (length function) 4)
471 (aref function 4)))
472 (if (eq (car-safe function) 'autoload)
473 (nth 2 function)
474 (if (eq (car-safe function) 'lambda)
475 (if (stringp (nth 2 function))
476 (nth 2 function)
477 (if (stringp (nth 3 function))
478 (nth 3 function)))))))
479 (if (integerp function)
480 nil
481 function))
482
483
484
485 (defun apropos-print (do-keys doc-fn spacing)
486 "Output result of various apropos commands with `apropos-regexp'.
487 APROPOS-ACCUMULATOR is a list. Optional DOC-FN is called for each element
488 of apropos-accumulator and may modify it resulting in (symbol fn-doc
489 var-doc [plist-doc]). Returns sorted list of symbols and documentation
490 found."
491 (if (null apropos-accumulator)
492 (message "No apropos matches for `%s'" apropos-regexp)
493 (if doc-fn
494 (funcall doc-fn apropos-accumulator))
495 (setq apropos-accumulator
496 (sort apropos-accumulator (lambda (a b)
497 (string-lessp (car a) (car b)))))
498 (and apropos-label-face
499 (or (symbolp apropos-label-face)
500 (facep apropos-label-face)) ; XEmacs
501 (setq apropos-label-face `(face ,apropos-label-face
502 mouse-face highlight)))
503 (with-output-to-temp-buffer "*Apropos*"
504 (let ((p apropos-accumulator)
505 (old-buffer (current-buffer))
506 symbol item point1 point2)
507 (set-buffer standard-output)
508 (apropos-mode)
509 ;; XEmacs change from (if window-system
510 (if (device-on-window-system-p)
511 (insert "If you move the mouse over text that changes color,\n"
512 (substitute-command-keys
513 "you can click \\[apropos-mouse-follow] to get more information.\n")))
514 (insert (substitute-command-keys
515 "Type \\[apropos-follow] in this buffer to get full documentation.\n\n"))
516 (while (consp p)
517 (or (not spacing) (bobp) (terpri))
518 (setq apropos-item (car p)
519 symbol (car apropos-item)
520 p (cdr p)
521 point1 (point))
522 (princ symbol) ; print symbol name
523 (setq point2 (point))
524 ;; Calculate key-bindings if we want them.
525 (and do-keys
526 (commandp symbol)
527 (indent-to 30 1)
528 (if (let ((keys
529 (save-excursion
530 (set-buffer old-buffer)
531 (where-is-internal symbol)))
532 filtered)
533 ;; Copy over the list of key sequences,
534 ;; omitting any that contain a buffer or a frame.
535 (while keys
536 (let ((key (car keys))
537 (i 0)
538 loser)
539 (while (< i (length key))
540 (if (or (framep (aref key i))
541 (bufferp (aref key i)))
542 (setq loser t))
543 (setq i (1+ i)))
544 (or loser
545 (setq filtered (cons key filtered))))
546 (setq keys (cdr keys)))
547 (setq item filtered))
548 ;; Convert the remaining keys to a string and insert.
549 (insert
550 (mapconcat
551 (lambda (key)
552 (setq key (key-description key))
553 (if apropos-keybinding-face
554 (put-text-property 0 (length key)
555 'face apropos-keybinding-face
556 key))
557 key)
558 item ", "))
559 (insert "Type ")
560 (insert "M-x")
561 (put-text-property (- (point) 3) (point)
562 'face apropos-keybinding-face)
563 (insert " " (symbol-name symbol) " ")
564 (insert "RET")
565 (put-text-property (- (point) 3) (point)
566 'face apropos-keybinding-face)))
567 (terpri)
568 ;; only now so we don't propagate text attributes all over
569 (put-text-property point1 point2 'item
570 (if (eval `(or ,@(cdr apropos-item)))
571 (car apropos-item)
572 apropos-item))
573 (if apropos-symbol-face
574 (put-text-property point1 point2 'face apropos-symbol-face))
575 (apropos-print-doc 'describe-function 1
576 (if (commandp symbol)
577 "Command"
578 (if (apropos-macrop symbol)
579 "Macro"
580 "Function"))
581 do-keys)
582 (if (get symbol 'custom-type)
583 (apropos-print-doc 'customize-variable-other-window 2
584 "User Option" do-keys)
585 (apropos-print-doc 'describe-variable 2
586 "Variable" do-keys))
587 (apropos-print-doc 'customize-other-window 6 "Group" do-keys)
588 (apropos-print-doc 'customize-face-other-window 5 "Face" do-keys)
589 (apropos-print-doc 'widget-browse-other-window 4 "Widget" do-keys)
590 (apropos-print-doc 'apropos-describe-plist 3
591 "Plist" nil)))))
592 (prog1 apropos-accumulator
593 (setq apropos-accumulator ()))) ; permit gc
594
595
596 (defun apropos-macrop (symbol)
597 "T if SYMBOL is a Lisp macro."
598 (and (fboundp symbol)
599 (consp (setq symbol
600 (symbol-function symbol)))
601 (or (eq (car symbol) 'macro)
602 (if (eq (car symbol) 'autoload)
603 (memq (nth 4 symbol)
604 '(macro t))))))
605
606
607 (defun apropos-print-doc (action i str do-keys)
608 (if (stringp (setq i (nth i apropos-item)))
609 (progn
610 (insert " ")
611 (put-text-property (- (point) 2) (1- (point))
612 'action action)
613 (insert str ": ")
614 (if apropos-label-face
615 (add-text-properties (- (point) (length str) 2)
616 (1- (point))
617 apropos-label-face))
618 (insert (if do-keys (substitute-command-keys i) i))
619 (or (bolp) (terpri)))))
620
621 (defun apropos-mouse-follow (event)
622 (interactive "e")
623 (let ((other (if (eq (current-buffer) (get-buffer "*Apropos*"))
624 ()
625 (current-buffer))))
626 (save-excursion
627 ;; XEmacs change from:
628 ;; (set-buffer (window-buffer (posn-window (event-start event))))
629 ;; (goto-char (posn-point (event-start event)))
630 (set-buffer (event-buffer event))
631 (goto-char (event-closest-point event))
632 ;; XEmacs change: following code seems useless
633 ;;(or (and (not (eobp)) (get-text-property (point) 'mouse-face))
634 ;; (and (not (bobp)) (get-text-property (1- (point)) 'mouse-face))
635 ;; (error "There is nothing to follow here"))
636 (apropos-follow other))))
637
638
639 (defun apropos-follow (&optional other)
640 (interactive)
641 (let* (;; Properties are always found at the beginning of the line.
642 (bol (save-excursion (beginning-of-line) (point)))
643 ;; If there is no `item' property here, look behind us.
644 (item (get-text-property bol 'item))
645 (item-at (if item nil (previous-single-property-change bol 'item)))
646 ;; Likewise, if there is no `action' property here, look in front.
647 (action (get-text-property bol 'action))
648 (action-at (if action nil (next-single-property-change bol 'action))))
649 (and (null item) item-at
650 (setq item (get-text-property (1- item-at) 'item)))
651 (and (null action) action-at
652 (setq action (get-text-property action-at 'action)))
653 (if (not (and item action))
654 (error "There is nothing to follow here"))
655 (if (consp item) (error "There is nothing to follow in `%s'" (car item)))
656 (if other (set-buffer other))
657 (funcall action item)))
658
659
660
661 (defun apropos-describe-plist (symbol)
662 "Display a pretty listing of SYMBOL's plist."
663 (with-output-to-temp-buffer "*Help*"
664 (set-buffer standard-output)
665 (princ "Symbol ")
666 (prin1 symbol)
667 (princ "'s plist is\n (")
668 (if apropos-symbol-face
669 (put-text-property 8 (- (point) 14) 'face apropos-symbol-face))
670 (insert (apropos-format-plist symbol "\n "))
671 (princ ")")
672 (print-help-return-message)))
673
674 (provide 'apropos) ; XEmacs
675
676 ;;; apropos.el ends here