code.delx.au - gnu-emacs/blob - lisp/apropos.el

   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 GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it 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 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU 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 ;;; Commentary:
  27
  28 ;; The ideas for this package were derived from the C code in
  29 ;; src/keymap.c and elsewhere.  The functions in this file should
  30 ;; always be byte-compiled for speed.  Someone should rewrite this in
  31 ;; C (as part of src/keymap.c) for speed.
  32
  33 ;; The idea for super-apropos is based on the original implementation
  34 ;; by Lynn Slater <lrs@esl.com>.
  35
  36 ;; History:
  37 ;; Fixed bug, current-local-map can return nil.
  38 ;; Change, doesn't calculate key-bindings unless needed.
  39 ;; Added super-apropos capability, changed print functions.
  40 ;;; Made fast-apropos and super-apropos share code.
  41 ;;; Sped up fast-apropos again.
  42 ;; Added apropos-do-all option.
  43 ;;; Added fast-command-apropos.
  44 ;; Changed doc strings to comments for helping functions.
  45 ;;; Made doc file buffer read-only, buried it.
  46 ;; Only call substitute-command-keys if do-all set.
  47
  48 ;; Optionally use configurable faces to make the output more legible.
  49 ;; Differentiate between command, function and macro.
  50 ;; Apropos-command (ex command-apropos) does cmd and optionally user var.
  51 ;; Apropos shows all 3 aspects of symbols (fn, var and plist)
  52 ;; Apropos-documentation (ex super-apropos) now finds all it should.
  53 ;; New apropos-value snoops through all values and optionally plists.
  54 ;; Reading DOC file doesn't load nroff.
  55 ;; Added hypertext following of documentation, mouse-2 on variable gives value
  56 ;;   from buffer in active window.
  57
  58 ;;; Code:
  59
  60 (defgroup apropos nil
  61   "Apropos commands for users and programmers"
  62   :group 'Help
  63   :prefix "apropos")
  64
  65 ;; I see a degradation of maybe 10-20% only.
  66 (defcustom apropos-do-all nil
  67   "*Whether the apropos commands should do more.
  68
  69 Slows them down more or less.  Set this non-nil if you have a fast machine."
  70   :group 'apropos
  71   :type 'boolean)
  72
  73
  74 (defcustom apropos-symbol-face (if window-system 'bold)
  75   "*Face for symbol name in apropos output or `nil'.
  76 This looks good, but slows down the commands several times."
  77   :group 'apropos
  78   :type 'face)
  79
  80 (defcustom apropos-keybinding-face (if window-system 'underline)
  81   "*Face for keybinding display in apropos output or `nil'.
  82 This looks good, but slows down the commands several times."
  83   :group 'apropos
  84   :type 'face)
  85
  86 (defcustom apropos-label-face (if window-system '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   :group 'apropos
  93   :type 'face)
  94
  95 (defcustom apropos-property-face (if window-system 'bold-italic)
  96   "*Face for property name in apropos output or `nil'.
  97 This looks good, but slows down the commands several times."
  98   :group 'apropos
  99   :type 'face)
 100
 101 (defcustom apropos-match-face (if window-system 'secondary-selection)
 102   "*Face for matching part in apropos-documentation/value output or `nil'.
 103 This looks good, but slows down the commands several times."
 104   :group 'apropos
 105   :type 'face)
 106
 107
 108 (defvar apropos-mode-map
 109   (let ((map (make-sparse-keymap)))
 110     (define-key map "\C-m" 'apropos-follow)
 111     (define-key map " "    'scroll-up)
 112     (define-key map "\177" 'scroll-down)
 113     (define-key map "q"    'quit-window)
 114     (define-key map [mouse-2] 'apropos-mouse-follow)
 115     (define-key map [down-mouse-2] nil)
 116     map)
 117   "Keymap used in Apropos mode.")
 118
 119
 120 (defvar apropos-regexp nil
 121   "Regexp used in current apropos run.")
 122
 123 (defvar apropos-files-scanned ()
 124   "List of elc files already scanned in current run of `apropos-documentation'.")
 125
 126 (defvar apropos-accumulator ()
 127   "Alist of symbols already found in current apropos run.")
 128
 129 (defvar apropos-item ()
 130   "Current item in or for apropos-accumulator.")
 131 \f
 132 (defun apropos-mode ()
 133   "Major mode for following hyperlinks in output of apropos commands.
 134
 135 \\{apropos-mode-map}"
 136   (interactive)
 137   (kill-all-local-variables)
 138   (use-local-map apropos-mode-map)
 139   (setq major-mode 'apropos-mode
 140         mode-name "Apropos"))
 141
 142 ;;;###autoload
 143 (defun apropos-variable (regexp &optional do-all)
 144   "Show user variables that match REGEXP.
 145 With optional prefix ARG or if `apropos-do-all' is non-nil, also show
 146 normal variables."
 147   (interactive (list (read-string
 148                       (concat "Apropos "
 149                               (if (or current-prefix-arg apropos-do-all)
 150                                   "variable"
 151                                 "user option")
 152                               " (regexp): "))
 153                      current-prefix-arg))
 154   (apropos-command regexp nil
 155                    (if (or do-all apropos-do-all)
 156                        #'(lambda (symbol)
 157                            (and (boundp symbol)
 158                                 (get symbol 'variable-documentation)))
 159                      'user-variable-p)))
 160
 161 ;; For auld lang syne:
 162 ;;;###autoload
 163 (fset 'command-apropos 'apropos-command)
 164 ;;;###autoload
 165 (defun apropos-command (apropos-regexp &optional do-all var-predicate)
 166   "Show commands (interactively callable functions) that match REGEXP.
 167 With optional prefix ARG, or if `apropos-do-all' is non-nil, also show
 168 noninteractive functions.
 169
 170 If VAR-PREDICATE is non-nil, show only variables, and only those that
 171 satisfy the predicate VAR-PREDICATE."
 172   (interactive (list (read-string (concat
 173                                    "Apropos command "
 174                                    (if (or current-prefix-arg
 175                                            apropos-do-all)
 176                                        "or function ")
 177                                    "(regexp): "))
 178                      current-prefix-arg))
 179   (let ((message
 180          (let ((standard-output (get-buffer-create "*Apropos*")))
 181            (print-help-return-message 'identity))))
 182     (or do-all (setq do-all apropos-do-all))
 183     (setq apropos-accumulator
 184           (apropos-internal apropos-regexp
 185                             (or var-predicate
 186                                 (if do-all 'functionp 'commandp))))
 187     (let ((tem apropos-accumulator))
 188       (while tem
 189         (if (get (car tem) 'apropos-inhibit)
 190             (setq apropos-accumulator (delq (car tem) apropos-accumulator)))
 191         (setq tem (cdr tem))))
 192     (if (apropos-print
 193          t
 194          (lambda (p)
 195            (let (doc symbol)
 196              (while p
 197                (setcar p (list
 198                           (setq symbol (car p))
 199                           (unless var-predicate
 200                             (if (functionp symbol)
 201                                 (if (setq doc (documentation symbol t))
 202                                     (substring doc 0 (string-match "\n" doc))
 203                                   "(not documented)")))
 204                           (and var-predicate
 205                                (funcall var-predicate symbol)
 206                                (if (setq doc (documentation-property
 207                                               symbol 'variable-documentation t))
 208                                    (substring doc 0
 209                                               (string-match "\n" doc))))))
 210                (setq p (cdr p)))))
 211          nil)
 212         (and message (message message)))))
 213
 214
 215 ;;;###autoload
 216 (defun apropos (apropos-regexp &optional do-all)
 217   "Show all bound symbols whose names match REGEXP.
 218 With optional prefix ARG or if `apropos-do-all' is non-nil, also show unbound
 219 symbols and key bindings, which is a little more time-consuming.
 220 Returns list of symbols and documentation found."
 221   (interactive "sApropos symbol (regexp): \nP")
 222   (setq apropos-accumulator
 223         (apropos-internal apropos-regexp
 224                           (and (not do-all)
 225                                (not apropos-do-all)
 226                                (lambda (symbol)
 227                                  (or (fboundp symbol)
 228                                      (boundp symbol)
 229                                      (facep symbol)
 230                                      (symbol-plist symbol))))))
 231   (let ((tem apropos-accumulator))
 232     (while tem
 233       (if (get (car tem) 'apropos-inhibit)
 234           (setq apropos-accumulator (delq (car tem) apropos-accumulator)))
 235       (setq tem (cdr tem))))
 236   (apropos-print
 237    (or do-all apropos-do-all)
 238    (lambda (p)
 239      (let (symbol doc properties)
 240        (while p
 241          (setcar p (list
 242                     (setq symbol (car p))
 243                     (when (fboundp symbol)
 244                       (if (setq doc (condition-case nil
 245                                         (documentation symbol t)
 246                                       (void-function
 247                                        "(alias for undefined function)")))
 248                           (substring doc 0 (string-match "\n" doc))
 249                         "(not documented)"))
 250                     (when (boundp symbol)
 251                       (if (setq doc (documentation-property
 252                                      symbol 'variable-documentation t))
 253                           (substring doc 0 (string-match "\n" doc))
 254                         "(not documented)"))
 255                     (when (setq properties (symbol-plist symbol))
 256                       (setq doc (list (car properties)))
 257                       (while (setq properties (cdr (cdr properties)))
 258                         (setq doc (cons (car properties) doc)))
 259                       (mapconcat #'symbol-name (nreverse doc) " "))
 260                     (when (get symbol 'widget-type)
 261                       (if (setq doc (documentation-property
 262                                      symbol 'widget-documentation t))
 263                           (substring doc 0
 264                                      (string-match "\n" doc))
 265                         "(not documented)"))
 266                     (when (facep symbol)
 267                       (if (setq doc (documentation-property
 268                                      symbol 'face-documentation t))
 269                           (substring doc 0
 270                                      (string-match "\n" doc))
 271                         "(not documented)"))
 272                     (when (get symbol 'custom-group)
 273                       (if (setq doc (documentation-property
 274                                      symbol 'group-documentation t))
 275                           (substring doc 0
 276                                      (string-match "\n" doc))
 277                         "(not documented)"))))
 278          (setq p (cdr p)))))
 279    nil))
 280
 281
 282 ;;;###autoload
 283 (defun apropos-value (apropos-regexp &optional do-all)
 284   "Show all symbols whose value's printed image matches REGEXP.
 285 With optional prefix ARG or if `apropos-do-all' is non-nil, also looks
 286 at the function and at the names and values of properties.
 287 Returns list of symbols and values found."
 288   (interactive "sApropos value (regexp): \nP")
 289   (or do-all (setq do-all apropos-do-all))
 290   (setq apropos-accumulator ())
 291    (let (f v p)
 292      (mapatoms
 293       (lambda (symbol)
 294         (setq f nil v nil p nil)
 295         (or (memq symbol '(apropos-regexp do-all apropos-accumulator
 296                                           symbol f v p))
 297             (setq v (apropos-value-internal 'boundp symbol 'symbol-value)))
 298         (if do-all
 299             (setq f (apropos-value-internal 'fboundp symbol 'symbol-function)
 300                   p (apropos-format-plist symbol "\n    " t)))
 301         (if (or f v p)
 302             (setq apropos-accumulator (cons (list symbol f v p)
 303                                             apropos-accumulator))))))
 304   (apropos-print nil nil t))
 305
 306
 307 ;;;###autoload
 308 (defun apropos-documentation (apropos-regexp &optional do-all)
 309   "Show symbols whose documentation contain matches for REGEXP.
 310 With optional prefix ARG or if `apropos-do-all' is non-nil, also use
 311 documentation that is not stored in the documentation file and show key
 312 bindings.
 313 Returns list of symbols and documentation found."
 314   (interactive "sApropos documentation (regexp): \nP")
 315   (or do-all (setq do-all apropos-do-all))
 316   (setq apropos-accumulator () apropos-files-scanned ())
 317   (let ((standard-input (get-buffer-create " apropos-temp"))
 318         f v)
 319     (unwind-protect
 320         (save-excursion
 321           (set-buffer standard-input)
 322           (apropos-documentation-check-doc-file)
 323           (if do-all
 324               (mapatoms
 325                (lambda (symbol)
 326                  (setq f (apropos-safe-documentation symbol)
 327                        v (get symbol 'variable-documentation))
 328                  (if (integerp v) (setq v))
 329                  (setq f (apropos-documentation-internal f)
 330                        v (apropos-documentation-internal v))
 331                  (if (or f v)
 332                      (if (setq apropos-item
 333                                (cdr (assq symbol apropos-accumulator)))
 334                          (progn
 335                            (if f
 336                                (setcar apropos-item f))
 337                            (if v
 338                                (setcar (cdr apropos-item) v)))
 339                        (setq apropos-accumulator
 340                              (cons (list symbol f v)
 341                                    apropos-accumulator)))))))
 342           (apropos-print nil nil t))
 343       (kill-buffer standard-input))))
 344
 345 \f
 346 (defun apropos-value-internal (predicate symbol function)
 347   (if (funcall predicate symbol)
 348       (progn
 349         (setq symbol (prin1-to-string (funcall function symbol)))
 350         (if (string-match apropos-regexp symbol)
 351             (progn
 352               (if apropos-match-face
 353                   (put-text-property (match-beginning 0) (match-end 0)
 354                                      'face apropos-match-face
 355                                      symbol))
 356               symbol)))))
 357
 358 (defun apropos-documentation-internal (doc)
 359   (if (consp doc)
 360       (apropos-documentation-check-elc-file (car doc))
 361     (and doc
 362          (string-match apropos-regexp doc)
 363          (progn
 364            (if apropos-match-face
 365                (put-text-property (match-beginning 0)
 366                                   (match-end 0)
 367                                   'face apropos-match-face
 368                                   (setq doc (copy-sequence doc))))
 369            doc))))
 370
 371 (defun apropos-format-plist (pl sep &optional compare)
 372   (setq pl (symbol-plist pl))
 373   (let (p p-out)
 374     (while pl
 375       (setq p (format "%s %S" (car pl) (nth 1 pl)))
 376       (if (or (not compare) (string-match apropos-regexp p))
 377           (if apropos-property-face
 378               (put-text-property 0 (length (symbol-name (car pl)))
 379                                  'face apropos-property-face p))
 380         (setq p nil))
 381       (if p
 382           (progn
 383             (and compare apropos-match-face
 384                  (put-text-property (match-beginning 0) (match-end 0)
 385                                     'face apropos-match-face
 386                                     p))
 387             (setq p-out (concat p-out (if p-out sep) p))))
 388       (setq pl (nthcdr 2 pl)))
 389     p-out))
 390
 391
 392 ;; Finds all documentation related to APROPOS-REGEXP in internal-doc-file-name.
 393
 394 (defun apropos-documentation-check-doc-file ()
 395   (let (type symbol (sepa 2) sepb beg end)
 396     (insert ?\^_)
 397     (backward-char)
 398     (insert-file-contents (concat doc-directory internal-doc-file-name))
 399     (forward-char)
 400     (while (save-excursion
 401              (setq sepb (search-forward "\^_"))
 402              (not (eobp)))
 403       (beginning-of-line 2)
 404       (if (save-restriction
 405             (narrow-to-region (point) (1- sepb))
 406             (re-search-forward apropos-regexp nil t))
 407           (progn
 408             (setq beg (match-beginning 0)
 409                   end (point))
 410             (goto-char (1+ sepa))
 411             (or (setq type (if (eq ?F (preceding-char))
 412                                1        ; function documentation
 413                              2)         ; variable documentation
 414                       symbol (read)
 415                       beg (- beg (point) 1)
 416                       end (- end (point) 1)
 417                       doc (buffer-substring (1+ (point)) (1- sepb))
 418                       apropos-item (assq symbol apropos-accumulator))
 419                 (setq apropos-item (list symbol nil nil)
 420                       apropos-accumulator (cons apropos-item
 421                                                 apropos-accumulator)))
 422             (if apropos-match-face
 423                 (put-text-property beg end 'face apropos-match-face doc))
 424             (setcar (nthcdr type apropos-item) doc)))
 425       (setq sepa (goto-char sepb)))))
 426
 427 (defun apropos-documentation-check-elc-file (file)
 428   (if (member file apropos-files-scanned)
 429       nil
 430     (let (symbol doc beg end this-is-a-variable)
 431       (setq apropos-files-scanned (cons file apropos-files-scanned))
 432       (erase-buffer)
 433       (insert-file-contents file)
 434       (while (search-forward "\n#@" nil t)
 435         ;; Read the comment length, and advance over it.
 436         (setq end (read)
 437               beg (1+ (point))
 438               end (+ (point) end -1))
 439         (forward-char)
 440         (if (save-restriction
 441               ;; match ^ and $ relative to doc string
 442               (narrow-to-region beg end)
 443               (re-search-forward apropos-regexp nil t))
 444             (progn
 445               (goto-char (+ end 2))
 446               (setq doc (buffer-substring beg end)
 447                     end (- (match-end 0) beg)
 448                     beg (- (match-beginning 0) beg)
 449                     this-is-a-variable (looking-at "(def\\(var\\|const\\) ")
 450                     symbol (progn
 451                              (skip-chars-forward "(a-z")
 452                              (forward-char)
 453                              (read))
 454                     symbol (if (consp symbol)
 455                                (nth 1 symbol)
 456                              symbol))
 457               (if (if this-is-a-variable
 458                       (get symbol 'variable-documentation)
 459                     (and (fboundp symbol) (apropos-safe-documentation symbol)))
 460                   (progn
 461                     (or (setq apropos-item (assq symbol apropos-accumulator))
 462                         (setq apropos-item (list symbol nil nil)
 463                               apropos-accumulator (cons apropos-item
 464                                                         apropos-accumulator)))
 465                     (if apropos-match-face
 466                         (put-text-property beg end 'face apropos-match-face
 467                                            doc))
 468                     (setcar (nthcdr (if this-is-a-variable 2 1)
 469                                     apropos-item)
 470                             doc)))))))))
 471
 472
 473
 474 (defun apropos-safe-documentation (function)
 475   "Like documentation, except it avoids calling `get_doc_string'.
 476 Will return nil instead."
 477   (while (and function (symbolp function))
 478     (setq function (if (fboundp function)
 479                        (symbol-function function))))
 480   (if (eq (car-safe function) 'macro)
 481       (setq function (cdr function)))
 482   (setq function (if (byte-code-function-p function)
 483                      (if (> (length function) 4)
 484                          (aref function 4))
 485                    (if (eq (car-safe function) 'autoload)
 486                        (nth 2 function)
 487                      (if (eq (car-safe function) 'lambda)
 488                          (if (stringp (nth 2 function))
 489                              (nth 2 function)
 490                            (if (stringp (nth 3 function))
 491                                (nth 3 function)))))))
 492   (if (integerp function)
 493       nil
 494     function))
 495
 496
 497
 498 (defun apropos-print (do-keys doc-fn spacing)
 499   "Output result of various apropos commands with `apropos-regexp'.
 500 APROPOS-ACCUMULATOR is a list.  Optional DOC-FN is called for each element
 501 of apropos-accumulator and may modify it resulting in (SYMBOL FN-DOC
 502 VAR-DOC [PLIST-DOC]).  Returns sorted list of symbols and documentation
 503 found."
 504   (if (null apropos-accumulator)
 505       (message "No apropos matches for `%s'" apropos-regexp)
 506     (if doc-fn
 507         (funcall doc-fn apropos-accumulator))
 508     (setq apropos-accumulator
 509           (sort apropos-accumulator (lambda (a b)
 510                                       (string-lessp (car a) (car b)))))
 511     (and apropos-label-face
 512          (symbolp apropos-label-face)
 513          (setq apropos-label-face `(face ,apropos-label-face
 514                                          mouse-face highlight)))
 515     (with-output-to-temp-buffer "*Apropos*"
 516       (let ((p apropos-accumulator)
 517             (old-buffer (current-buffer))
 518             symbol item point1 point2)
 519         (set-buffer standard-output)
 520         (apropos-mode)
 521         (if window-system
 522             (insert "If you move the mouse over text that changes color,\n"
 523                     (substitute-command-keys
 524                      "you can click \\[apropos-mouse-follow] to get more information.\n")))
 525         (insert (substitute-command-keys
 526                  "In this buffer, type \\[apropos-follow] to get full documentation.\n\n"))
 527         (while (consp p)
 528           (or (not spacing) (bobp) (terpri))
 529           (setq apropos-item (car p)
 530                 symbol (car apropos-item)
 531                 p (cdr p)
 532                 point1 (point))
 533           (princ symbol)                        ; print symbol name
 534           (setq point2 (point))
 535           ;; Calculate key-bindings if we want them.
 536           (and do-keys
 537                (commandp symbol)
 538                (indent-to 30 1)
 539                (if (let ((keys
 540                           (save-excursion
 541                             (set-buffer old-buffer)
 542                             (where-is-internal symbol)))
 543                          filtered)
 544                      ;; Copy over the list of key sequences,
 545                      ;; omitting any that contain a buffer or a frame.
 546                      (while keys
 547                        (let ((key (car keys))
 548                              (i 0)
 549                              loser)
 550                          (while (< i (length key))
 551                            (if (or (framep (aref key i))
 552                                    (bufferp (aref key i)))
 553                                (setq loser t))
 554                            (setq i (1+ i)))
 555                          (or loser
 556                              (setq filtered (cons key filtered))))
 557                        (setq keys (cdr keys)))
 558                      (setq item filtered))
 559                    ;; Convert the remaining keys to a string and insert.
 560                    (insert
 561                     (mapconcat
 562                      (lambda (key)
 563                        (setq key (key-description key))
 564                        (if apropos-keybinding-face
 565                            (put-text-property 0 (length key)
 566                                               'face apropos-keybinding-face
 567                                               key))
 568                        key)
 569                      item ", "))
 570                  (insert "M-x")
 571                  (put-text-property (- (point) 3) (point)
 572                                     'face apropos-keybinding-face)
 573                  (insert " " (symbol-name symbol) " ")
 574                  (insert "RET")
 575                  (put-text-property (- (point) 3) (point)
 576                                     'face apropos-keybinding-face)))
 577           (terpri)
 578           ;; only now so we don't propagate text attributes all over
 579           (put-text-property point1 point2 'item
 580                              (if (eval `(or ,@(cdr apropos-item)))
 581                                  (car apropos-item)
 582                                apropos-item))
 583           (if apropos-symbol-face
 584               (put-text-property point1 point2 'face apropos-symbol-face))
 585           (apropos-print-doc 'describe-function 1
 586                              (if (commandp symbol)
 587                                  "Command"
 588                                (if (apropos-macrop symbol)
 589                                    "Macro"
 590                                  "Function"))
 591                              t)
 592           ;; We used to use customize-variable-other-window instead
 593           ;; for a customizable variable, but that is slow.
 594           ;; It is better to show an ordinary help buffer
 595           ;; and let the user click on the customization button
 596           ;; in that buffer, if he wants to.
 597           (apropos-print-doc 'describe-variable 2 "Variable" t)
 598           (apropos-print-doc 'customize-group-other-window 6 "Group" t)
 599           (apropos-print-doc 'customize-face-other-window 5 "Face" t)
 600           (apropos-print-doc 'widget-browse-other-window 4 "Widget" t)
 601           (apropos-print-doc 'apropos-describe-plist 3
 602                              "Plist" nil)))))
 603   (prog1 apropos-accumulator
 604     (setq apropos-accumulator ())))     ; permit gc
 605
 606
 607 (defun apropos-macrop (symbol)
 608   "T if SYMBOL is a Lisp macro."
 609   (and (fboundp symbol)
 610        (consp (setq symbol
 611                     (symbol-function symbol)))
 612        (or (eq (car symbol) 'macro)
 613            (if (eq (car symbol) 'autoload)
 614                (memq (nth 4 symbol)
 615                      '(macro t))))))
 616
 617
 618 (defun apropos-print-doc (action i str do-keys)
 619   (if (stringp (setq i (nth i apropos-item)))
 620       (progn
 621         (insert "  ")
 622         (put-text-property (- (point) 2) (1- (point))
 623                            'action action)
 624         (insert str ": ")
 625         (if apropos-label-face
 626             (add-text-properties (- (point) (length str) 2)
 627                                  (1- (point))
 628                                  apropos-label-face))
 629         (insert (if do-keys (substitute-command-keys i) i))
 630         (or (bolp) (terpri)))))
 631
 632
 633 (defun apropos-mouse-follow (event)
 634   (interactive "e")
 635   (let ((other (if (eq (current-buffer) (get-buffer "*Apropos*"))
 636                    ()
 637                  (current-buffer))))
 638     (save-excursion
 639       (set-buffer (window-buffer (posn-window (event-start event))))
 640       (goto-char (posn-point (event-start event)))
 641       (or (and (not (eobp)) (get-text-property (point) 'mouse-face))
 642           (and (not (bobp)) (get-text-property (1- (point)) 'mouse-face))
 643           (error "There is nothing to follow here"))
 644       (apropos-follow other))))
 645
 646
 647 (defun apropos-follow (&optional other)
 648   (interactive)
 649   (let* (;; Properties are always found at the beginning of the line.
 650          (bol (save-excursion (beginning-of-line) (point)))
 651          ;; If there is no `item' property here, look behind us.
 652          (item (get-text-property bol 'item))
 653          (item-at (if item nil (previous-single-property-change bol 'item)))
 654          ;; Likewise, if there is no `action' property here, look in front.
 655          (action (get-text-property bol 'action))
 656          (action-at (if action nil (next-single-property-change bol 'action))))
 657     (and (null item) item-at
 658          (setq item (get-text-property (1- item-at) 'item)))
 659     (and (null action) action-at
 660          (setq action (get-text-property action-at 'action)))
 661     (if (not (and item action))
 662         (error "There is nothing to follow here"))
 663     (if (consp item) (error "There is nothing to follow in `%s'" (car item)))
 664     (if other (set-buffer other))
 665     (funcall action item)))
 666
 667
 668
 669 (defun apropos-describe-plist (symbol)
 670   "Display a pretty listing of SYMBOL's plist."
 671   (with-output-to-temp-buffer "*Help*"
 672     (set-buffer standard-output)
 673     (princ "Symbol ")
 674     (prin1 symbol)
 675     (princ "'s plist is\n (")
 676     (if apropos-symbol-face
 677         (put-text-property 8 (- (point) 14) 'face apropos-symbol-face))
 678     (insert (apropos-format-plist symbol "\n  "))
 679     (princ ")")
 680     (print-help-return-message)))
 681
 682 (provide 'apropos)
 683
 684 ;;; apropos.el ends here