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 <occitan@esperanto.org>
   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 'bold
  75   "*Face for symbol name in Apropos output, or nil for none."
  76   :group 'apropos
  77   :type 'face)
  78
  79 (defcustom apropos-keybinding-face 'underline
  80   "*Face for lists of keybinding in Apropos output, or nil for none."
  81   :group 'apropos
  82   :type 'face)
  83
  84 (defcustom apropos-label-face 'italic
  85   "*Face for label (`Command', `Variable' ...) in Apropos output.
  86 A value of nil means don't use any special font for them, and also
  87 turns off mouse highlighting."
  88   :group 'apropos
  89   :type 'face)
  90
  91 (defcustom apropos-property-face 'bold-italic
  92   "*Face for property name in apropos output, or nil for none."
  93   :group 'apropos
  94   :type 'face)
  95
  96 (defcustom apropos-match-face 'secondary-selection
  97   "*Face for matching text in Apropos documentation/value, or nil for none.
  98 This applies when you look for matches in the documentation or variable value
  99 for the regexp; the part that matches gets displayed in this font."
 100   :group 'apropos
 101   :type 'face)
 102
 103
 104 (defvar apropos-mode-map
 105   (let ((map (make-sparse-keymap)))
 106     (define-key map "\C-m" 'apropos-follow)
 107     (define-key map " "    'scroll-up)
 108     (define-key map "\177" 'scroll-down)
 109     (define-key map "q"    'quit-window)
 110     (define-key map [mouse-2] 'apropos-mouse-follow)
 111     (define-key map [down-mouse-2] nil)
 112     map)
 113   "Keymap used in Apropos mode.")
 114
 115
 116 (defvar apropos-regexp nil
 117   "Regexp used in current apropos run.")
 118
 119 (defvar apropos-files-scanned ()
 120   "List of elc files already scanned in current run of `apropos-documentation'.")
 121
 122 (defvar apropos-accumulator ()
 123   "Alist of symbols already found in current apropos run.")
 124
 125 (defvar apropos-item ()
 126   "Current item in or for apropos-accumulator.")
 127 \f
 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
 138 ;;;###autoload
 139 (defun apropos-variable (regexp &optional do-all)
 140   "Show user variables that match REGEXP.
 141 With optional prefix ARG or if `apropos-do-all' is non-nil, also show
 142 normal variables."
 143   (interactive (list (read-string
 144                       (concat "Apropos "
 145                               (if (or current-prefix-arg apropos-do-all)
 146                                   "variable"
 147                                 "user option")
 148                               " (regexp): "))
 149                      current-prefix-arg))
 150   (apropos-command regexp nil
 151                    (if (or do-all apropos-do-all)
 152                        #'(lambda (symbol)
 153                            (and (boundp symbol)
 154                                 (get symbol 'variable-documentation)))
 155                      'user-variable-p)))
 156
 157 ;; For auld lang syne:
 158 ;;;###autoload
 159 (fset 'command-apropos 'apropos-command)
 160 ;;;###autoload
 161 (defun apropos-command (apropos-regexp &optional do-all var-predicate)
 162   "Show commands (interactively callable functions) that match REGEXP.
 163 With optional prefix ARG, or if `apropos-do-all' is non-nil, also show
 164 noninteractive functions.
 165
 166 If VAR-PREDICATE is non-nil, show only variables, and only those that
 167 satisfy the predicate VAR-PREDICATE."
 168   (interactive (list (read-string (concat
 169                                    "Apropos command "
 170                                    (if (or current-prefix-arg
 171                                            apropos-do-all)
 172                                        "or function ")
 173                                    "(regexp): "))
 174                      current-prefix-arg))
 175   (let ((message
 176          (let ((standard-output (get-buffer-create "*Apropos*")))
 177            (print-help-return-message 'identity))))
 178     (or do-all (setq do-all apropos-do-all))
 179     (setq apropos-accumulator
 180           (apropos-internal apropos-regexp
 181                             (or var-predicate
 182                                 (if do-all 'functionp 'commandp))))
 183     (let ((tem apropos-accumulator))
 184       (while tem
 185         (if (get (car tem) 'apropos-inhibit)
 186             (setq apropos-accumulator (delq (car tem) apropos-accumulator)))
 187         (setq tem (cdr tem))))
 188     (let ((p apropos-accumulator)
 189           doc symbol)
 190       (while p
 191         (setcar p (list
 192                    (setq symbol (car p))
 193                    (unless var-predicate
 194                      (if (functionp symbol)
 195                          (if (setq doc (documentation symbol t))
 196                              (substring doc 0 (string-match "\n" doc))
 197                            "(not documented)")))
 198                    (and var-predicate
 199                         (funcall var-predicate symbol)
 200                         (if (setq doc (documentation-property
 201                                        symbol 'variable-documentation t))
 202                             (substring doc 0
 203                                        (string-match "\n" doc))))))
 204         (setq p (cdr p))))
 205     (and (apropos-print t nil)
 206          message
 207          (message message))))
 208
 209
 210 ;;;###autoload
 211 (defun apropos (apropos-regexp &optional do-all)
 212   "Show all bound symbols whose names match REGEXP.
 213 With optional prefix ARG or if `apropos-do-all' is non-nil, also show unbound
 214 symbols and key bindings, which is a little more time-consuming.
 215 Returns list of symbols and documentation found."
 216   (interactive "sApropos symbol (regexp): \nP")
 217   (setq apropos-accumulator
 218         (apropos-internal apropos-regexp
 219                           (and (not do-all)
 220                                (not apropos-do-all)
 221                                (lambda (symbol)
 222                                  (or (fboundp symbol)
 223                                      (boundp symbol)
 224                                      (facep symbol)
 225                                      (symbol-plist symbol))))))
 226   (let ((tem apropos-accumulator))
 227     (while tem
 228       (if (get (car tem) 'apropos-inhibit)
 229           (setq apropos-accumulator (delq (car tem) apropos-accumulator)))
 230       (setq tem (cdr tem))))
 231   (let ((p apropos-accumulator)
 232         symbol doc properties)
 233     (while p
 234       (setcar p (list
 235                  (setq symbol (car p))
 236                  (when (fboundp symbol)
 237                    (if (setq doc (condition-case nil
 238                                      (documentation symbol t)
 239                                    (void-function
 240                                     "(alias for undefined function)")))
 241                        (substring doc 0 (string-match "\n" doc))
 242                      "(not documented)"))
 243                  (when (boundp symbol)
 244                    (if (setq doc (documentation-property
 245                                   symbol 'variable-documentation t))
 246                        (substring doc 0 (string-match "\n" doc))
 247                      "(not documented)"))
 248                  (when (setq properties (symbol-plist symbol))
 249                    (setq doc (list (car properties)))
 250                    (while (setq properties (cdr (cdr properties)))
 251                      (setq doc (cons (car properties) doc)))
 252                    (mapconcat #'symbol-name (nreverse doc) " "))
 253                  (when (get symbol 'widget-type)
 254                    (if (setq doc (documentation-property
 255                                   symbol 'widget-documentation t))
 256                        (substring doc 0
 257                                   (string-match "\n" doc))
 258                      "(not documented)"))
 259                  (when (facep symbol)
 260                    (if (setq doc (documentation-property
 261                                   symbol 'face-documentation t))
 262                        (substring doc 0
 263                                   (string-match "\n" doc))
 264                      "(not documented)"))
 265                  (when (get symbol 'custom-group)
 266                    (if (setq doc (documentation-property
 267                                   symbol 'group-documentation t))
 268                        (substring doc 0
 269                                   (string-match "\n" doc))
 270                      "(not documented)"))))
 271       (setq p (cdr p))))
 272   (apropos-print
 273    (or do-all apropos-do-all)
 274    nil))
 275
 276
 277 ;;;###autoload
 278 (defun apropos-value (apropos-regexp &optional do-all)
 279   "Show all symbols whose value's printed image matches REGEXP.
 280 With optional prefix ARG or if `apropos-do-all' is non-nil, also looks
 281 at the function and at the names and values of properties.
 282 Returns list of symbols and values found."
 283   (interactive "sApropos value (regexp): \nP")
 284   (or do-all (setq do-all apropos-do-all))
 285   (setq apropos-accumulator ())
 286    (let (f v p)
 287      (mapatoms
 288       (lambda (symbol)
 289         (setq f nil v nil p nil)
 290         (or (memq symbol '(apropos-regexp do-all apropos-accumulator
 291                                           symbol f v p))
 292             (setq v (apropos-value-internal 'boundp symbol 'symbol-value)))
 293         (if do-all
 294             (setq f (apropos-value-internal 'fboundp symbol 'symbol-function)
 295                   p (apropos-format-plist symbol "\n    " t)))
 296         (if (or f v p)
 297             (setq apropos-accumulator (cons (list symbol f v p)
 298                                             apropos-accumulator))))))
 299   (apropos-print nil t))
 300
 301
 302 ;;;###autoload
 303 (defun apropos-documentation (apropos-regexp &optional do-all)
 304   "Show symbols whose documentation contain matches for REGEXP.
 305 With optional prefix ARG or if `apropos-do-all' is non-nil, also use
 306 documentation that is not stored in the documentation file and show key
 307 bindings.
 308 Returns list of symbols and documentation found."
 309   (interactive "sApropos documentation (regexp): \nP")
 310   (or do-all (setq do-all apropos-do-all))
 311   (setq apropos-accumulator () apropos-files-scanned ())
 312   (let ((standard-input (get-buffer-create " apropos-temp"))
 313         f v)
 314     (unwind-protect
 315         (save-excursion
 316           (set-buffer standard-input)
 317           (apropos-documentation-check-doc-file)
 318           (if do-all
 319               (mapatoms
 320                (lambda (symbol)
 321                  (setq f (apropos-safe-documentation symbol)
 322                        v (get symbol 'variable-documentation))
 323                  (if (integerp v) (setq v))
 324                  (setq f (apropos-documentation-internal f)
 325                        v (apropos-documentation-internal v))
 326                  (if (or f v)
 327                      (if (setq apropos-item
 328                                (cdr (assq symbol apropos-accumulator)))
 329                          (progn
 330                            (if f
 331                                (setcar apropos-item f))
 332                            (if v
 333                                (setcar (cdr apropos-item) v)))
 334                        (setq apropos-accumulator
 335                              (cons (list symbol f v)
 336                                    apropos-accumulator)))))))
 337           (apropos-print nil t))
 338       (kill-buffer standard-input))))
 339
 340 \f
 341 (defun apropos-value-internal (predicate symbol function)
 342   (if (funcall predicate symbol)
 343       (progn
 344         (setq symbol (prin1-to-string (funcall function symbol)))
 345         (if (string-match apropos-regexp symbol)
 346             (progn
 347               (if apropos-match-face
 348                   (put-text-property (match-beginning 0) (match-end 0)
 349                                      'face apropos-match-face
 350                                      symbol))
 351               symbol)))))
 352
 353 (defun apropos-documentation-internal (doc)
 354   (if (consp doc)
 355       (apropos-documentation-check-elc-file (car doc))
 356     (and doc
 357          (string-match apropos-regexp doc)
 358          (progn
 359            (if apropos-match-face
 360                (put-text-property (match-beginning 0)
 361                                   (match-end 0)
 362                                   'face apropos-match-face
 363                                   (setq doc (copy-sequence doc))))
 364            doc))))
 365
 366 (defun apropos-format-plist (pl sep &optional compare)
 367   (setq pl (symbol-plist pl))
 368   (let (p p-out)
 369     (while pl
 370       (setq p (format "%s %S" (car pl) (nth 1 pl)))
 371       (if (or (not compare) (string-match apropos-regexp p))
 372           (if apropos-property-face
 373               (put-text-property 0 (length (symbol-name (car pl)))
 374                                  'face apropos-property-face p))
 375         (setq p nil))
 376       (if p
 377           (progn
 378             (and compare apropos-match-face
 379                  (put-text-property (match-beginning 0) (match-end 0)
 380                                     'face apropos-match-face
 381                                     p))
 382             (setq p-out (concat p-out (if p-out sep) p))))
 383       (setq pl (nthcdr 2 pl)))
 384     p-out))
 385
 386
 387 ;; Finds all documentation related to APROPOS-REGEXP in internal-doc-file-name.
 388
 389 (defun apropos-documentation-check-doc-file ()
 390   (let (type symbol (sepa 2) sepb beg end)
 391     (insert ?\^_)
 392     (backward-char)
 393     (insert-file-contents (concat doc-directory internal-doc-file-name))
 394     (forward-char)
 395     (while (save-excursion
 396              (setq sepb (search-forward "\^_"))
 397              (not (eobp)))
 398       (beginning-of-line 2)
 399       (if (save-restriction
 400             (narrow-to-region (point) (1- sepb))
 401             (re-search-forward apropos-regexp nil t))
 402           (progn
 403             (setq beg (match-beginning 0)
 404                   end (point))
 405             (goto-char (1+ sepa))
 406             (or (setq type (if (eq ?F (preceding-char))
 407                                1        ; function documentation
 408                              2)         ; variable documentation
 409                       symbol (read)
 410                       beg (- beg (point) 1)
 411                       end (- end (point) 1)
 412                       doc (buffer-substring (1+ (point)) (1- sepb))
 413                       apropos-item (assq symbol apropos-accumulator))
 414                 (setq apropos-item (list symbol nil nil)
 415                       apropos-accumulator (cons apropos-item
 416                                                 apropos-accumulator)))
 417             (if apropos-match-face
 418                 (put-text-property beg end 'face apropos-match-face doc))
 419             (setcar (nthcdr type apropos-item) doc)))
 420       (setq sepa (goto-char sepb)))))
 421
 422 (defun apropos-documentation-check-elc-file (file)
 423   (if (member file apropos-files-scanned)
 424       nil
 425     (let (symbol doc beg end this-is-a-variable)
 426       (setq apropos-files-scanned (cons file apropos-files-scanned))
 427       (erase-buffer)
 428       (insert-file-contents file)
 429       (while (search-forward "\n#@" nil t)
 430         ;; Read the comment length, and advance over it.
 431         (setq end (read)
 432               beg (1+ (point))
 433               end (+ (point) end -1))
 434         (forward-char)
 435         (if (save-restriction
 436               ;; match ^ and $ relative to doc string
 437               (narrow-to-region beg end)
 438               (re-search-forward apropos-regexp nil t))
 439             (progn
 440               (goto-char (+ end 2))
 441               (setq doc (buffer-substring beg end)
 442                     end (- (match-end 0) beg)
 443                     beg (- (match-beginning 0) beg)
 444                     this-is-a-variable (looking-at "(def\\(var\\|const\\) ")
 445                     symbol (progn
 446                              (skip-chars-forward "(a-z")
 447                              (forward-char)
 448                              (read))
 449                     symbol (if (consp symbol)
 450                                (nth 1 symbol)
 451                              symbol))
 452               (if (if this-is-a-variable
 453                       (get symbol 'variable-documentation)
 454                     (and (fboundp symbol) (apropos-safe-documentation symbol)))
 455                   (progn
 456                     (or (setq apropos-item (assq symbol apropos-accumulator))
 457                         (setq apropos-item (list symbol nil nil)
 458                               apropos-accumulator (cons apropos-item
 459                                                         apropos-accumulator)))
 460                     (if apropos-match-face
 461                         (put-text-property beg end 'face apropos-match-face
 462                                            doc))
 463                     (setcar (nthcdr (if this-is-a-variable 2 1)
 464                                     apropos-item)
 465                             doc)))))))))
 466
 467
 468
 469 (defun apropos-safe-documentation (function)
 470   "Like documentation, except it avoids calling `get_doc_string'.
 471 Will return nil instead."
 472   (while (and function (symbolp function))
 473     (setq function (if (fboundp function)
 474                        (symbol-function function))))
 475   (if (eq (car-safe function) 'macro)
 476       (setq function (cdr function)))
 477   (setq function (if (byte-code-function-p function)
 478                      (if (> (length function) 4)
 479                          (aref function 4))
 480                    (if (eq (car-safe function) 'autoload)
 481                        (nth 2 function)
 482                      (if (eq (car-safe function) 'lambda)
 483                          (if (stringp (nth 2 function))
 484                              (nth 2 function)
 485                            (if (stringp (nth 3 function))
 486                                (nth 3 function)))))))
 487   (if (integerp function)
 488       nil
 489     function))
 490
 491
 492
 493 (defvar apropos-label-properties nil
 494   "List of face properties to use for a label.
 495 Bound by `apropos-print' for use by `apropos-print-doc'.")
 496
 497 (defun apropos-print (do-keys spacing)
 498   "Output result of apropos searching into buffer `*Apropos*'.
 499 The value of `apropos-accumulator' is the list of items to output.
 500 Each element should have the format (SYMBOL FN-DOC VAR-DOC [PLIST-DOC]).
 501 The return value is the list that was in `apropos-accumulator', sorted
 502 alphabetically by symbol name; but this function also sets
 503 `apropos-accumulator' to nil before returning."
 504   (if (null apropos-accumulator)
 505       (message "No apropos matches for `%s'" apropos-regexp)
 506     (setq apropos-accumulator
 507           (sort apropos-accumulator (lambda (a b)
 508                                       (string-lessp (car a) (car b)))))
 509     (setq apropos-label-properties
 510           (if (and apropos-label-face
 511                    (symbolp apropos-label-face))
 512               `(face ,apropos-label-face
 513                      mouse-face highlight)))
 514     (with-output-to-temp-buffer "*Apropos*"
 515       (let ((p apropos-accumulator)
 516             (old-buffer (current-buffer))
 517             symbol item point1 point2)
 518         (set-buffer standard-output)
 519         (apropos-mode)
 520         (if window-system
 521             (insert "If you move the mouse over text that changes color,\n"
 522                     (substitute-command-keys
 523                      "you can click \\[apropos-mouse-follow] to get more information.\n")))
 524         (insert (substitute-command-keys
 525                  "In this buffer, type \\[apropos-follow] to get full documentation.\n\n"))
 526         (while (consp p)
 527           (or (not spacing) (bobp) (terpri))
 528           (setq apropos-item (car p)
 529                 symbol (car apropos-item)
 530                 p (cdr p)
 531                 point1 (point))
 532           (princ symbol)                        ; print symbol name
 533           (setq point2 (point))
 534           ;; Calculate key-bindings if we want them.
 535           (and do-keys
 536                (commandp symbol)
 537                (indent-to 30 1)
 538                (if (let ((keys
 539                           (save-excursion
 540                             (set-buffer old-buffer)
 541                             (where-is-internal symbol)))
 542                          filtered)
 543                      ;; Copy over the list of key sequences,
 544                      ;; omitting any that contain a buffer or a frame.
 545                      (while keys
 546                        (let ((key (car keys))
 547                              (i 0)
 548                              loser)
 549                          (while (< i (length key))
 550                            (if (or (framep (aref key i))
 551                                    (bufferp (aref key i)))
 552                                (setq loser t))
 553                            (setq i (1+ i)))
 554                          (or loser
 555                              (setq filtered (cons key filtered))))
 556                        (setq keys (cdr keys)))
 557                      (setq item filtered))
 558                    ;; Convert the remaining keys to a string and insert.
 559                    (insert
 560                     (mapconcat
 561                      (lambda (key)
 562                        (setq key (condition-case ()
 563                                      (key-description key)
 564                                    (error)))
 565                        (if apropos-keybinding-face
 566                            (put-text-property 0 (length key)
 567                                               'face apropos-keybinding-face
 568                                               key))
 569                        key)
 570                      item ", "))
 571                  (insert "M-x")
 572                  (put-text-property (- (point) 3) (point)
 573                                     'face apropos-keybinding-face)
 574                  (insert " " (symbol-name symbol) " ")
 575                  (insert "RET")
 576                  (put-text-property (- (point) 3) (point)
 577                                     'face apropos-keybinding-face)))
 578           (terpri)
 579           ;; only now so we don't propagate text attributes all over
 580           (put-text-property point1 point2 'item
 581                              (if (eval `(or ,@(cdr apropos-item)))
 582                                  (car apropos-item)
 583                                apropos-item))
 584           (if apropos-symbol-face
 585               (put-text-property point1 point2 'face apropos-symbol-face))
 586           (apropos-print-doc 'describe-function 1
 587                              (if (commandp symbol)
 588                                  "Command"
 589                                (if (apropos-macrop symbol)
 590                                    "Macro"
 591                                  "Function"))
 592                              t)
 593           ;; We used to use customize-variable-other-window instead
 594           ;; for a customizable variable, but that is slow.
 595           ;; It is better to show an ordinary help buffer
 596           ;; and let the user click on the customization button
 597           ;; in that buffer, if he wants to.
 598           (apropos-print-doc 'describe-variable 2 "Variable" t)
 599           (apropos-print-doc 'customize-group-other-window 6 "Group" t)
 600           (apropos-print-doc 'customize-face-other-window 5 "Face" t)
 601           (apropos-print-doc 'widget-browse-other-window 4 "Widget" t)
 602           (apropos-print-doc 'apropos-describe-plist 3
 603                              "Plist" nil))
 604         (setq buffer-read-only t))))
 605   (prog1 apropos-accumulator
 606     (setq apropos-accumulator ())))     ; permit gc
 607
 608
 609 (defun apropos-macrop (symbol)
 610   "T if SYMBOL is a Lisp macro."
 611   (and (fboundp symbol)
 612        (consp (setq symbol
 613                     (symbol-function symbol)))
 614        (or (eq (car symbol) 'macro)
 615            (if (eq (car symbol) 'autoload)
 616                (memq (nth 4 symbol)
 617                      '(macro t))))))
 618
 619
 620 (defun apropos-print-doc (action i str do-keys)
 621   (if (stringp (setq i (nth i apropos-item)))
 622       (progn
 623         (insert "  ")
 624         (put-text-property (- (point) 2) (1- (point))
 625                            'action action)
 626         (insert str ": ")
 627         (if apropos-label-properties
 628             (add-text-properties (- (point) (length str) 2)
 629                                  (1- (point))
 630                                  apropos-label-properties))
 631         (insert (if do-keys (substitute-command-keys i) i))
 632         (or (bolp) (terpri)))))
 633
 634
 635 (defun apropos-mouse-follow (event)
 636   (interactive "e")
 637   (let ((other (if (eq (current-buffer) (get-buffer "*Apropos*"))
 638                    ()
 639                  (current-buffer))))
 640     (save-excursion
 641       (set-buffer (window-buffer (posn-window (event-start event))))
 642       (goto-char (posn-point (event-start event)))
 643       (or (and (not (eobp)) (get-text-property (point) 'mouse-face))
 644           (and (not (bobp)) (get-text-property (1- (point)) 'mouse-face))
 645           (error "There is nothing to follow here"))
 646       (apropos-follow other))))
 647
 648
 649 (defun apropos-follow (&optional other)
 650   (interactive)
 651   (let* (;; Properties are always found at the beginning of the line.
 652          (bol (save-excursion (beginning-of-line) (point)))
 653          ;; If there is no `item' property here, look behind us.
 654          (item (get-text-property bol 'item))
 655          (item-at (if item nil (previous-single-property-change bol 'item)))
 656          ;; Likewise, if there is no `action' property here, look in front.
 657          (action (get-text-property bol 'action))
 658          (action-at (if action nil (next-single-property-change bol 'action))))
 659     (and (null item) item-at
 660          (setq item (get-text-property (1- item-at) 'item)))
 661     (and (null action) action-at
 662          (setq action (get-text-property action-at 'action)))
 663     (if (not (and item action))
 664         (error "There is nothing to follow here"))
 665     (if (consp item) (error "There is nothing to follow in `%s'" (car item)))
 666     (if other (set-buffer other))
 667     (funcall action item)))
 668
 669
 670
 671 (defun apropos-describe-plist (symbol)
 672   "Display a pretty listing of SYMBOL's plist."
 673   (with-output-to-temp-buffer "*Help*"
 674     (set-buffer standard-output)
 675     (princ "Symbol ")
 676     (prin1 symbol)
 677     (princ "'s plist is\n (")
 678     (if apropos-symbol-face
 679         (put-text-property 8 (- (point) 14) 'face apropos-symbol-face))
 680     (insert (apropos-format-plist symbol "\n  "))
 681     (princ ")")
 682     (print-help-return-message)))
 683
 684 (provide 'apropos)
 685
 686 ;;; apropos.el ends here