lisp/facemenu.el

   1 ;;; facemenu.el --- create a face menu for interactively adding fonts to text
   2
   3 ;; Copyright (c) 1994, 1995, 1996 Free Software Foundation, Inc.
   4
   5 ;; Author: Boris Goldowsky <boris@gnu.ai.mit.edu>
   6 ;; Keywords: faces
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software; you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation; either version 2, or (at your option)
  13 ;; any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  22 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  23 ;; Boston, MA 02111-1307, USA.
  24
  25 ;;; Commentary:
  26
  27 ;; This file defines a menu of faces (bold, italic, etc) which allows you to
  28 ;; set the face used for a region of the buffer.  Some faces also have
  29 ;; keybindings, which are shown in the menu.  Faces with names beginning with
  30 ;; "fg:" or "bg:", as in "fg:red", are treated specially.
  31 ;; Such faces are assumed to consist only of a foreground (if "fg:") or
  32 ;; background (if "bg:") color.  They are thus put into the color submenus
  33 ;; rather than the general Face submenu.  These faces can also be
  34 ;; automatically created by selecting the "Other..." menu items in the
  35 ;; "Foreground" and "Background" submenus.
  36 ;;
  37 ;; The menu also contains submenus for indentation and justification-changing
  38 ;; commands.
  39
  40 ;;; Usage:
  41 ;; Selecting a face from the menu or typing the keyboard equivalent will
  42 ;; change the region to use that face.  If you use transient-mark-mode and the
  43 ;; region is not active, the face will be remembered and used for the next
  44 ;; insertion.  It will be forgotten if you move point or make other
  45 ;; modifications before inserting or typing anything.
  46 ;;
  47 ;; Faces can be selected from the keyboard as well.
  48 ;; The standard keybindings are M-g (or ESC g) + letter:
  49 ;; M-g i = "set italic",  M-g b = "set bold", etc.
  50
  51 ;;; Customization:
  52 ;; An alternative set of keybindings that may be easier to type can be set up
  53 ;; using "Alt" or "Hyper" keys.  This requires that you either have or create
  54 ;; an Alt or Hyper key on your keyboard.  On my keyboard, there is a key
  55 ;; labeled "Alt", but to make it act as an Alt key I have to put this command
  56 ;; into my .xinitrc:
  57 ;;    xmodmap -e "add Mod3 = Alt_L"
  58 ;; Or, I can make it into a Hyper key with this:
  59 ;;    xmodmap -e "keysym Alt_L = Hyper_L" -e "add Mod2 = Hyper_L"
  60 ;; Check with local X-perts for how to do it on your system.
  61 ;; Then you can define your keybindings with code like this in your .emacs:
  62 ;;   (setq facemenu-keybindings
  63 ;;    '((default     . [?\H-d])
  64 ;;      (bold        . [?\H-b])
  65 ;;      (italic      . [?\H-i])
  66 ;;      (bold-italic . [?\H-l])
  67 ;;      (underline   . [?\H-u])))
  68 ;;   (facemenu-update)
  69 ;;   (setq facemenu-keymap global-map)
  70 ;;   (define-key global-map [?\H-c] 'facemenu-set-foreground) ; set fg color
  71 ;;   (define-key global-map [?\H-C] 'facemenu-set-background) ; set bg color
  72 ;;
  73 ;; The order of the faces that appear in the menu and their keybindings can be
  74 ;; controlled by setting the variables `facemenu-keybindings' and
  75 ;; `facemenu-new-faces-at-end'.  List faces that you don't use in documents
  76 ;; (eg, `region') in `facemenu-unlisted-faces'.
  77
  78 ;;; Known Problems:
  79 ;; Bold and Italic do not combine to create bold-italic if you select them
  80 ;; both, although most other combinations (eg bold + underline + some color)
  81 ;; do the intuitive thing.
  82 ;;
  83 ;; There is at present no way to display what the faces look like in
  84 ;; the menu itself.
  85 ;;
  86 ;; `list-faces-display' shows the faces in a different order than
  87 ;; this menu, which could be confusing.  I do /not/ sort the list
  88 ;; alphabetically, because I like the default order: it puts the most
  89 ;; basic, common fonts first.
  90 ;;
  91 ;; Please send me any other problems, comments or ideas.
  92
  93 ;;; Code:
  94
  95 (provide 'facemenu)
  96
  97 ;;; Provide some binding for startup:
  98 ;;;###autoload (define-key global-map "\M-g" 'facemenu-keymap)
  99 ;;;###autoload (autoload 'facemenu-keymap "facemenu" "Keymap for face-changing commands." t 'keymap)
 100
 101 ;; Global bindings:
 102 (define-key global-map [C-down-mouse-2] 'facemenu-menu)
 103 (define-key global-map "\M-g" 'facemenu-keymap)
 104
 105 (defvar facemenu-keybindings
 106   '((default     . "d")
 107     (bold        . "b")
 108     (italic      . "i")
 109     (bold-italic . "l") ; {bold} intersect {italic} = {l}
 110     (underline   . "u"))
 111   "Alist of interesting faces and keybindings.
 112 Each element is itself a list: the car is the name of the face,
 113 the next element is the key to use as a keyboard equivalent of the menu item;
 114 the binding is made in `facemenu-keymap'.
 115
 116 The faces specifically mentioned in this list are put at the top of
 117 the menu, in the order specified.  All other faces which are defined,
 118 except for those in `facemenu-unlisted-faces', are listed after them,
 119 but get no keyboard equivalents.
 120
 121 If you change this variable after loading facemenu.el, you will need to call
 122 `facemenu-update' to make it take effect.")
 123
 124 (defvar facemenu-new-faces-at-end t
 125   "*Where in the menu to insert newly-created faces.
 126 This should be nil to put them at the top of the menu, or t to put them
 127 just before \"Other\" at the end.")
 128
 129 (defvar facemenu-unlisted-faces
 130   '(modeline region secondary-selection highlight scratch-face)
 131   "*List of faces not to include in the Face menu.
 132 You can set this list before loading facemenu.el, or add a face to it before
 133 creating that face if you do not want it to be listed.  If you change the
 134 variable so as to eliminate faces that have already been added to the menu,
 135 call `facemenu-update' to recalculate the menu contents.
 136
 137 If this variable is t, no faces will be added to the menu.  This is useful for
 138 temporarily turning off the feature that automatically adds faces to the menu
 139 when they are created.")
 140
 141 ;;;###autoload
 142 (defvar facemenu-face-menu
 143   (let ((map (make-sparse-keymap "Face")))
 144     (define-key map "o" (cons "Other..." 'facemenu-set-face))
 145     map)
 146   "Menu keymap for faces.")
 147 ;;;###autoload
 148 (defalias 'facemenu-face-menu facemenu-face-menu)
 149
 150 ;;;###autoload
 151 (defvar facemenu-foreground-menu
 152   (let ((map (make-sparse-keymap "Foreground Color")))
 153     (define-key map "o" (cons "Other..." 'facemenu-set-foreground))
 154     map)
 155   "Menu keymap for foreground colors.")
 156 ;;;###autoload
 157 (defalias 'facemenu-foreground-menu facemenu-foreground-menu)
 158
 159 ;;;###autoload
 160 (defvar facemenu-background-menu
 161   (let ((map (make-sparse-keymap "Background Color")))
 162     (define-key map "o" (cons "Other..." 'facemenu-set-background))
 163     map)
 164   "Menu keymap for background colors")
 165 ;;;###autoload
 166 (defalias 'facemenu-background-menu facemenu-background-menu)
 167
 168 ;;;###autoload
 169 (defvar facemenu-special-menu
 170   (let ((map (make-sparse-keymap "Special")))
 171     (define-key map [?s] (cons "Remove Special" 'facemenu-remove-special))
 172     (define-key map [?t] (cons "Intangible" 'facemenu-set-intangible))
 173     (define-key map [?v] (cons "Invisible" 'facemenu-set-invisible))
 174     (define-key map [?r] (cons "Read-Only" 'facemenu-set-read-only))
 175     map)
 176   "Menu keymap for non-face text-properties.")
 177 ;;;###autoload
 178 (defalias 'facemenu-special-menu facemenu-special-menu)
 179
 180 ;;;###autoload
 181 (defvar facemenu-justification-menu
 182   (let ((map (make-sparse-keymap "Justification")))
 183     (define-key map [?c] (cons "Center" 'set-justification-center))
 184     (define-key map [?b] (cons "Full" 'set-justification-full))
 185     (define-key map [?r] (cons "Right" 'set-justification-right))
 186     (define-key map [?l] (cons "Left" 'set-justification-left))
 187     (define-key map [?u] (cons "Unfilled" 'set-justification-none))
 188     map)
 189   "Submenu for text justification commands.")
 190 ;;;###autoload
 191 (defalias 'facemenu-justification-menu facemenu-justification-menu)
 192
 193 ;;;###autoload
 194 (defvar facemenu-indentation-menu
 195   (let ((map (make-sparse-keymap "Indentation")))
 196     (define-key map [decrease-right-margin]
 197       (cons "Indent Right Less" 'decrease-right-margin))
 198     (define-key map [increase-right-margin]
 199       (cons "Indent Right More" 'increase-right-margin))
 200     (define-key map [decrease-left-margin]
 201       (cons "Indent Less" 'decrease-left-margin))
 202     (define-key map [increase-left-margin]
 203       (cons "Indent More" 'increase-left-margin))
 204     map)
 205   "Submenu for indentation commands.")
 206 ;;;###autoload
 207 (defalias 'facemenu-indentation-menu facemenu-indentation-menu)
 208
 209 ;; This is split up to avoid an overlong line in loaddefs.el.
 210 ;;;###autoload
 211 (defvar facemenu-menu nil
 212   "Facemenu top-level menu keymap.")
 213 ;;;###autoload
 214 (setq facemenu-menu (make-sparse-keymap "Text Properties"))
 215 ;;;###autoload
 216 (let ((map facemenu-menu))
 217   (define-key map [dc] (cons "Display Colors" 'list-colors-display))
 218   (define-key map [df] (cons "Display Faces" 'list-faces-display))
 219   (define-key map [dp] (cons "List Properties" 'list-text-properties-at))
 220   (define-key map [ra] (cons "Remove All" 'facemenu-remove-all))
 221   (define-key map [rm] (cons "Remove Properties" 'facemenu-remove-props))
 222   (define-key map [s1] (list "-----------------")))
 223 ;;;###autoload
 224 (let ((map facemenu-menu))
 225   (define-key map [in] (cons "Indentation" 'facemenu-indentation-menu))
 226   (define-key map [ju] (cons "Justification" 'facemenu-justification-menu))
 227   (define-key map [s2] (list "-----------------"))
 228   (define-key map [sp] (cons "Special Properties" 'facemenu-special-menu))
 229   (define-key map [bg] (cons "Background Color" 'facemenu-background-menu))
 230   (define-key map [fg] (cons "Foreground Color" 'facemenu-foreground-menu))
 231   (define-key map [fc] (cons "Face" 'facemenu-face-menu)))
 232 ;;;###autoload
 233 (defalias 'facemenu-menu facemenu-menu)
 234
 235 (defvar facemenu-keymap
 236   (let ((map (make-sparse-keymap "Set face")))
 237     (define-key map "o" (cons "Other..." 'facemenu-set-face))
 238     map)
 239   "Keymap for face-changing commands.
 240 `Facemenu-update' fills in the keymap according to the bindings
 241 requested in `facemenu-keybindings'.")
 242 (defalias 'facemenu-keymap facemenu-keymap)
 243
 244
 245 (defvar facemenu-add-face-function nil
 246   "Function called at beginning of text to change or `nil'.
 247 This function is passed the FACE to set and END of text to change, and must
 248 return a string which is inserted.  It may set `facemenu-end-add-face'.")
 249
 250 (defvar facemenu-end-add-face nil
 251   "String to insert or function called at end of text to change or `nil'.
 252 This function is passed the FACE to set, and must return a string which is
 253 inserted.")
 254
 255 (defvar facemenu-remove-face-function nil
 256   "When non-nil, this is a function called to remove faces.
 257 This function is passed the START and END of text to change.
 258 May also be `t' meaning to use `facemenu-add-face-function'.")
 259
 260 ;;; Internal Variables
 261
 262 (defvar facemenu-color-alist nil
 263   ;; Don't initialize here; that doesn't work if preloaded.
 264   "Alist of colors, used for completion.
 265 If null, `facemenu-read-color' will set it.")
 266
 267 (defun facemenu-update ()
 268   "Add or update the \"Face\" menu in the menu bar.
 269 You can call this to update things if you change any of the menu configuration
 270 variables."
 271   (interactive)
 272
 273   ;; Add each defined face to the menu.
 274   (facemenu-iterate 'facemenu-add-new-face
 275                     (facemenu-complete-face-list facemenu-keybindings)))
 276
 277 ;;;###autoload
 278 (defun facemenu-set-face (face &optional start end)
 279   "Add FACE to the region or next character typed.
 280 It will be added to the top of the face list; any faces lower on the list that
 281 will not show through at all will be removed.
 282
 283 Interactively, the face to be used is read with the minibuffer.
 284
 285 If the region is active and there is no prefix argument,
 286 this command sets the region to the requested face.
 287
 288 Otherwise, this command specifies the face for the next character
 289 inserted.  Moving point or switching buffers before
 290 typing a character to insert cancels the specification."
 291   (interactive (list (read-face-name "Use face: ")))
 292   (barf-if-buffer-read-only)
 293   (facemenu-add-new-face face)
 294   (if (and mark-active (not current-prefix-arg))
 295       (let ((start (or start (region-beginning)))
 296             (end (or end (region-end))))
 297         (facemenu-add-face face start end))
 298     (facemenu-add-face face)))
 299
 300 ;;;###autoload
 301 (defun facemenu-set-foreground (color &optional start end)
 302   "Set the foreground color of the region or next character typed.
 303 The color is prompted for.  A face named `fg:color' is used \(or created).
 304 If the region is active, it will be set to the requested face.  If
 305 it is inactive \(even if mark-even-if-inactive is set) the next
 306 character that is typed \(via `self-insert-command') will be set to
 307 the selected face.  Moving point or switching buffers before
 308 typing a character cancels the request."
 309   (interactive (list (facemenu-read-color "Foreground color: ")))
 310   (let ((face (intern (concat "fg:" color))))
 311     (or (facemenu-get-face face)
 312         (error "Unknown color: %s" color))
 313     (facemenu-set-face face start end)))
 314
 315 ;;;###autoload
 316 (defun facemenu-set-background (color &optional start end)
 317   "Set the background color of the region or next character typed.
 318 The color is prompted for.  A face named `bg:color' is used \(or created).
 319 If the region is active, it will be set to the requested face.  If
 320 it is inactive \(even if mark-even-if-inactive is set) the next
 321 character that is typed \(via `self-insert-command') will be set to
 322 the selected face.  Moving point or switching buffers before
 323 typing a character cancels the request."
 324   (interactive (list (facemenu-read-color "Background color: ")))
 325   (let ((face (intern (concat "bg:" color))))
 326     (or (facemenu-get-face face)
 327         (error "Unknown color: %s" color))
 328     (facemenu-set-face face start end)))
 329
 330 ;;;###autoload
 331 (defun facemenu-set-face-from-menu (face start end)
 332   "Set the face of the region or next character typed.
 333 This function is designed to be called from a menu; the face to use
 334 is the menu item's name.
 335
 336 If the region is active and there is no prefix argument,
 337 this command sets the region to the requested face.
 338
 339 Otherwise, this command specifies the face for the next character
 340 inserted.  Moving point or switching buffers before
 341 typing a character to insert cancels the specification."
 342   (interactive (list last-command-event
 343                      (if (and mark-active (not current-prefix-arg))
 344                          (region-beginning))
 345                      (if (and mark-active (not current-prefix-arg))
 346                          (region-end))))
 347   (barf-if-buffer-read-only)
 348   (facemenu-get-face face)
 349   (if start
 350       (facemenu-add-face face start end)
 351     (facemenu-add-face face)))
 352
 353 ;;;###autoload
 354 (defun facemenu-set-invisible (start end)
 355   "Make the region invisible.
 356 This sets the `invisible' text property; it can be undone with
 357 `facemenu-remove-special'."
 358   (interactive "r")
 359   (add-text-properties start end '(invisible t)))
 360
 361 ;;;###autoload
 362 (defun facemenu-set-intangible (start end)
 363   "Make the region intangible: disallow moving into it.
 364 This sets the `intangible' text property; it can be undone with
 365 `facemenu-remove-special'."
 366   (interactive "r")
 367   (add-text-properties start end '(intangible t)))
 368
 369 ;;;###autoload
 370 (defun facemenu-set-read-only (start end)
 371   "Make the region unmodifiable.
 372 This sets the `read-only' text property; it can be undone with
 373 `facemenu-remove-special'."
 374   (interactive "r")
 375   (add-text-properties start end '(read-only t)))
 376
 377 ;;;###autoload
 378 (defun facemenu-remove-props (start end)
 379   "Remove all text properties that facemenu added to region."
 380   (interactive "*r") ; error if buffer is read-only despite the next line.
 381   (let ((inhibit-read-only t))
 382     (remove-text-properties
 383      start end '(face nil invisible nil intangible nil
 384                       read-only nil category nil))))
 385
 386 ;;;###autoload
 387 (defun facemenu-remove-all (start end)
 388   "Remove all text properties from the region."
 389   (interactive "*r") ; error if buffer is read-only despite the next line.
 390   (let ((inhibit-read-only t))
 391     (set-text-properties start end nil)))
 392
 393 ;;;###autoload
 394 (defun facemenu-remove-special (start end)
 395   "Remove all the \"special\" text properties from the region.
 396 These special properties include `invisible', `intangible' and `read-only'."
 397   (interactive "*r") ; error if buffer is read-only despite the next line.
 398   (let ((inhibit-read-only t))
 399     (remove-text-properties
 400      start end '(invisible nil intangible nil read-only nil))))
 401
 402 ;;;###autoload
 403 (defun list-text-properties-at (p)
 404   "Pop up a buffer listing text-properties at LOCATION."
 405   (interactive "d")
 406   (let ((props (text-properties-at p))
 407         category
 408         str)
 409     (if (null props)
 410         (message "None")
 411       (if (and (not (cdr (cdr props)))
 412                (not (eq (car props) 'category))
 413                (< (length (setq str (format "Text property at %d:  %s  %S"
 414                                             p (car props) (car (cdr props)))))
 415                   (frame-width)))
 416           (message "%s" str)
 417         (with-output-to-temp-buffer "*Text Properties*"
 418           (princ (format "Text properties at %d:\n\n" p))
 419           (while props
 420             (if (eq (car props) 'category)
 421                 (setq category (car (cdr props))))
 422             (princ (format "%-20s %S\n"
 423                            (car props) (car (cdr props))))
 424             (setq props (cdr (cdr props))))
 425           (if category
 426               (progn
 427                 (setq props (symbol-plist category))
 428                 (princ (format "\nCategory %s:\n\n" category))
 429                 (while props
 430                   (princ (format "%-20s %S\n"
 431                                  (car props) (car (cdr props))))
 432                   (if (eq (car props) 'category)
 433                       (setq category (car (cdr props))))
 434                   (setq props (cdr (cdr props)))))))))))
 435
 436 ;;;###autoload
 437 (defun facemenu-read-color (&optional prompt)
 438   "Read a color using the minibuffer."
 439   (let ((col (completing-read (or prompt "Color: ")
 440                               (or facemenu-color-alist
 441                                   (if window-system
 442                                       (mapcar 'list (x-defined-colors))))
 443                               nil t)))
 444     (if (equal "" col)
 445         nil
 446       col)))
 447
 448 ;;;###autoload
 449 (defun list-colors-display (&optional list)
 450   "Display names of defined colors, and show what they look like.
 451 If the optional argument LIST is non-nil, it should be a list of
 452 colors to display.  Otherwise, this command computes a list
 453 of colors that the current display can handle."
 454   (interactive)
 455   (if (and (null list) window-system)
 456       (progn
 457         (setq list (x-defined-colors))
 458         ;; Delete duplicate colors.
 459         (let ((l list))
 460           (while (cdr l)
 461             (if (facemenu-color-equal (car l) (car (cdr l)))
 462                 (setcdr l (cdr (cdr l)))
 463               (setq l (cdr l)))))))
 464   (with-output-to-temp-buffer "*Colors*"
 465     (save-excursion
 466       (set-buffer standard-output)
 467       (let ((facemenu-unlisted-faces t)
 468             s)
 469         (while list
 470           (setq s (point))
 471           (insert (car list))
 472           (indent-to 20)
 473           (put-text-property s (point) 'face
 474                              (facemenu-get-face
 475                               (intern (concat "bg:" (car list)))))
 476           (setq s (point))
 477           (insert "  " (car list) "\n")
 478           (put-text-property s (point) 'face
 479                              (facemenu-get-face
 480                               (intern (concat "fg:" (car list)))))
 481           (setq list (cdr list)))))))
 482
 483 (defun facemenu-color-equal (a b)
 484   "Return t if colors A and B are the same color.
 485 A and B should be strings naming colors.
 486 This function queries the window-system server to find out what the
 487 color names mean.  It returns nil if the colors differ or if it can't
 488 determine the correct answer."
 489   (cond ((equal a b) t)
 490         ((and (memq window-system '(x w32))
 491               (equal (x-color-values a) (x-color-values b))))
 492         ((eq window-system 'pc)
 493          (and (x-color-defined-p a) (x-color-defined-p b)
 494               (eq (msdos-color-translate a) (msdos-color-translate b))))))
 495
 496 (defun facemenu-add-face (face &optional start end)
 497   "Add FACE to text between START and END.
 498 If START is `nil' or START to END is empty, add FACE to next typed character
 499 instead.  For each section of that region that has a different face property,
 500 FACE will be consed onto it, and other faces that are completely hidden by
 501 that will be removed from the list.
 502 If `facemenu-add-face-function' and maybe `facemenu-end-add-face' are non-`nil'
 503 they are used to set the face information.
 504
 505 As a special case, if FACE is `default', then the region is left with NO face
 506 text property.  Otherwise, selecting the default face would not have any
 507 effect.  See `facemenu-remove-face-function'."
 508   (interactive "*xFace: \nr")
 509   (if (and (eq face 'default)
 510            (not (eq facemenu-remove-face-function t)))
 511       (if facemenu-remove-face-function
 512           (funcall facemenu-remove-face-function start end)
 513         (if (and start (< start end))
 514             (remove-text-properties start end '(face default))
 515           (setq self-insert-face 'default
 516                 self-insert-face-command this-command)))
 517     (if facemenu-add-face-function
 518         (save-excursion
 519           (if end (goto-char end))
 520           (save-excursion
 521             (if start (goto-char start))
 522             (insert-before-markers
 523              (funcall facemenu-add-face-function face end)))
 524           (if facemenu-end-add-face
 525               (insert (if (stringp facemenu-end-add-face)
 526                           facemenu-end-add-face
 527                         (funcall facemenu-end-add-face face)))))
 528       (if (and start (< start end))
 529           (let ((part-start start) part-end)
 530             (while (not (= part-start end))
 531               (setq part-end (next-single-property-change part-start 'face
 532                                                           nil end))
 533               (let ((prev (get-text-property part-start 'face)))
 534                 (put-text-property part-start part-end 'face
 535                                    (if (null prev)
 536                                        face
 537                                      (facemenu-active-faces
 538                                       (cons face
 539                                             (if (listp prev)
 540                                                 prev
 541                                               (list prev)))))))
 542               (setq part-start part-end)))
 543         (setq self-insert-face (if (eq last-command self-insert-face-command)
 544                                    (cons face (if (listp self-insert-face)
 545                                                   self-insert-face
 546                                                 (list self-insert-face)))
 547                                  face)
 548               self-insert-face-command this-command)))))
 549
 550 (defun facemenu-active-faces (face-list &optional frame)
 551   "Return from FACE-LIST those faces that would be used for display.
 552 This means each face attribute is not specified in a face earlier in FACE-LIST
 553 and such a face is therefore active when used to display text.
 554 If the optional argument FRAME is given, use the faces in that frame; otherwise
 555 use the selected frame.  If t, then the global, non-frame faces are used."
 556   (let* ((mask-atts (copy-sequence (internal-get-face (car face-list) frame)))
 557          (active-list (list (car face-list)))
 558          (face-list (cdr face-list))
 559          (mask-len (length mask-atts)))
 560     (while face-list
 561       (if (let ((face-atts (internal-get-face (car face-list) frame))
 562                 (i mask-len) (useful nil))
 563             (while (> (setq i (1- i)) 1)
 564               (and (aref face-atts i) (not (aref mask-atts i))
 565                    (aset mask-atts i (setq useful t))))
 566             useful)
 567           (setq active-list (cons (car face-list) active-list)))
 568       (setq face-list (cdr face-list)))
 569     (nreverse active-list)))
 570
 571 (defun facemenu-get-face (symbol)
 572   "Make sure FACE exists.
 573 If not, it is created.  If it is created and is of the form `fg:color', then
 574 set the foreground to that color. If of the form `bg:color', set the
 575 background.  In any case, add it to the appropriate menu.  Returns the face,
 576 or nil if given a bad color."
 577   (if (or (internal-find-face symbol)
 578           (let* ((face (make-face symbol))
 579                  (name (symbol-name symbol))
 580                  (color (substring name 3)))
 581             (cond ((string-match "^fg:" name)
 582                    (set-face-foreground face color)
 583                    (and window-system
 584                         (x-color-defined-p color)))
 585                   ((string-match "^bg:" name)
 586                    (set-face-background face color)
 587                    (and window-system
 588                         (x-color-defined-p color)))
 589                   (t))))
 590       symbol))
 591
 592 (defun facemenu-add-new-face (face)
 593   "Add a FACE to the appropriate Face menu.
 594 Automatically called when a new face is created."
 595   (let* ((name (symbol-name face))
 596          menu docstring
 597          (key (cdr (assoc face facemenu-keybindings)))
 598          function menu-val)
 599     (cond ((string-match "^fg:" name)
 600            (setq name (substring name 3))
 601            (setq docstring
 602                  (format "Select foreground color %s for subsequent insertion."
 603                          name))
 604            (setq menu 'facemenu-foreground-menu))
 605           ((string-match "^bg:" name)
 606            (setq name (substring name 3))
 607            (setq docstring
 608                  (format "Select background color %s for subsequent insertion."
 609                          name))
 610            (setq menu 'facemenu-background-menu))
 611           (t
 612            (setq docstring
 613                  (format "Select face `%s' for subsequent insertion."
 614                          name))
 615            (setq menu 'facemenu-face-menu)))
 616     (cond ((eq t facemenu-unlisted-faces))
 617           ((memq face facemenu-unlisted-faces))
 618           (key ; has a keyboard equivalent.  These go at the front.
 619            (setq function (intern (concat "facemenu-set-" name)))
 620            (fset function
 621                  `(lambda ()
 622                     ,docstring
 623                     (interactive)
 624                     (facemenu-set-face (quote ,face))))
 625            (define-key 'facemenu-keymap key (cons name function))
 626            (define-key menu key (cons name function)))
 627           ((facemenu-iterate ; check if equivalent face is already in the menu
 628             (lambda (m) (and (listp m)
 629                              (symbolp (car m))
 630                              (face-equal (car m) face)))
 631             (cdr (symbol-function menu))))
 632           (t   ; No keyboard equivalent.  Figure out where to put it:
 633            (setq key (vector face)
 634                  function 'facemenu-set-face-from-menu
 635                  menu-val (symbol-function menu))
 636            (if (and facemenu-new-faces-at-end
 637                    (> (length menu-val) 3))
 638                (define-key-after menu-val key (cons name function)
 639                  (car (nth (- (length menu-val) 3) menu-val)))
 640              (define-key menu key (cons name function))))))
 641   nil) ; Return nil for facemenu-iterate
 642
 643 (defun facemenu-complete-face-list (&optional oldlist)
 644   "Return list of all faces that look different.
 645 Starts with given ALIST of faces, and adds elements only if they display
 646 differently from any face already on the list.
 647 The faces on ALIST will end up at the end of the returned list, in reverse
 648 order."
 649   (let ((list (nreverse (mapcar 'car oldlist))))
 650     (facemenu-iterate
 651      (lambda (new-face)
 652        (if (not (memq new-face list))
 653            (setq list (cons new-face list)))
 654        nil)
 655      (nreverse (face-list)))
 656     list))
 657
 658 (defun facemenu-iterate (func iterate-list)
 659   "Apply FUNC to each element of LIST until one returns non-nil.
 660 Returns the non-nil value it found, or nil if all were nil."
 661   (while (and iterate-list (not (funcall func (car iterate-list))))
 662     (setq iterate-list (cdr iterate-list)))
 663   (car iterate-list))
 664
 665 (facemenu-update)
 666
 667 ;;; facemenu.el ends here