lisp/hi-lock.el

   1 ;;; hi-lock.el --- minor mode for interactive automatic highlighting  -*- lexical-binding: t -*-
   2
   3 ;; Copyright (C) 2000-2015 Free Software Foundation, Inc.
   4
   5 ;; Author: David M. Koppelman <koppel@ece.lsu.edu>
   6 ;; Keywords: faces, minor-mode, matching, display
   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 3 of the License, or
  13 ;; (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24 ;;
  25 ;;  With the hi-lock commands text matching interactively entered
  26 ;;  regexp's can be highlighted.  For example, `M-x highlight-regexp
  27 ;;  RET clearly RET RET' will highlight all occurrences of `clearly'
  28 ;;  using a yellow background face.  New occurrences of `clearly' will
  29 ;;  be highlighted as they are typed.  `M-x unhighlight-regexp RET'
  30 ;;  will remove the highlighting.  Any existing face can be used for
  31 ;;  highlighting and a set of appropriate faces is provided.  The
  32 ;;  regexps can be written into the current buffer in a form that will
  33 ;;  be recognized the next time the corresponding file is read (when
  34 ;;  file patterns is turned on).
  35 ;;
  36 ;;  Applications:
  37 ;;
  38 ;;    In program source code highlight a variable to quickly see all
  39 ;;    places it is modified or referenced:
  40 ;;    M-x highlight-regexp RET ground_contact_switches_closed RET RET
  41 ;;
  42 ;;    In a shell or other buffer that is showing lots of program
  43 ;;    output, highlight the parts of the output you're interested in:
  44 ;;    M-x highlight-regexp RET Total execution time [0-9]+ RET hi-blue-b RET
  45 ;;
  46 ;;    In buffers displaying tables, highlight the lines you're interested in:
  47 ;;    M-x highlight-lines-matching-regexp RET January 2000 RET hi-black-b RET
  48 ;;
  49 ;;    When writing text, highlight personal cliches.  This can be
  50 ;;    amusing.
  51 ;;    M-x highlight-phrase RET as can be seen RET RET
  52 ;;
  53 ;;  Setup:
  54 ;;
  55 ;;    Put the following code in your init file.  This turns on
  56 ;;    hi-lock mode and adds a "Regexp Highlighting" entry
  57 ;;    to the edit menu.
  58 ;;
  59 ;;    (global-hi-lock-mode 1)
  60 ;;
  61 ;;    To enable the use of patterns found in files (presumably placed
  62 ;;    there by hi-lock) include the following in your init file:
  63 ;;
  64 ;;    (setq hi-lock-file-patterns-policy 'ask)
  65 ;;
  66 ;;    If you get tired of being asked each time a file is loaded replace
  67 ;;    `ask' with a function that returns t if patterns should be read.
  68 ;;
  69 ;;    You might also want to bind the hi-lock commands to more
  70 ;;    finger-friendly sequences:
  71
  72 ;;    (define-key hi-lock-map "\C-z\C-h" 'highlight-lines-matching-regexp)
  73 ;;    (define-key hi-lock-map "\C-zi" 'hi-lock-find-patterns)
  74 ;;    (define-key hi-lock-map "\C-zh" 'highlight-regexp)
  75 ;;    (define-key hi-lock-map "\C-zp" 'highlight-phrase)
  76 ;;    (define-key hi-lock-map "\C-zr" 'unhighlight-regexp)
  77 ;;    (define-key hi-lock-map "\C-zb" 'hi-lock-write-interactive-patterns))
  78
  79 ;;    See the documentation for hi-lock-mode `C-h f hi-lock-mode' for
  80 ;;    additional instructions.
  81
  82 ;; Sample file patterns:
  83
  84 ; Hi-lock: (("^;;; .*" (0 (quote hi-black-hb) t)))
  85 ; Hi-lock: ( ("make-variable-buffer-\\(local\\)" (0 font-lock-keyword-face)(1 'italic append)))))
  86 ; Hi-lock: end
  87
  88 ;;; Code:
  89
  90 (require 'font-lock)
  91
  92 (defgroup hi-lock nil
  93   "Interactively add and remove font-lock patterns for highlighting text."
  94   :link '(custom-manual "(emacs)Highlight Interactively")
  95   :group 'font-lock)
  96
  97 (defcustom hi-lock-file-patterns-range 10000
  98   "Limit of search in a buffer for hi-lock patterns.
  99 When a file is visited and hi-lock mode is on, patterns starting
 100 up to this limit are added to font-lock's patterns.  See documentation
 101 of functions `hi-lock-mode' and `hi-lock-find-patterns'."
 102   :type 'integer
 103   :group 'hi-lock)
 104
 105 (defcustom hi-lock-highlight-range 200000
 106   "Size of area highlighted by hi-lock when font-lock not active.
 107 Font-lock is not active in buffers that do their own highlighting,
 108 such as the buffer created by `list-colors-display'.  In those buffers
 109 hi-lock patterns will only be applied over a range of
 110 `hi-lock-highlight-range' characters.  If font-lock is active then
 111 highlighting will be applied throughout the buffer."
 112   :type 'integer
 113   :group 'hi-lock)
 114
 115 (defcustom hi-lock-exclude-modes
 116   '(rmail-mode mime/viewer-mode gnus-article-mode)
 117   "List of major modes in which hi-lock will not run.
 118 For security reasons since font lock patterns can specify function
 119 calls."
 120   :type '(repeat symbol)
 121   :group 'hi-lock)
 122
 123 (defcustom hi-lock-file-patterns-policy 'ask
 124   "Specify when hi-lock should use patterns found in file.
 125 If `ask', prompt when patterns found in buffer; if bound to a function,
 126 use patterns when function returns t (function is called with patterns
 127 as first argument); if nil or `never' or anything else, don't use file
 128 patterns."
 129   :type '(choice (const :tag "Do not use file patterns" never)
 130                  (const :tag "Ask about file patterns" ask)
 131                  (function :tag "Function to check file patterns"))
 132   :group 'hi-lock
 133   :version "22.1")
 134
 135 ;; It can have a function value.
 136 (put 'hi-lock-file-patterns-policy 'risky-local-variable t)
 137
 138 (defcustom hi-lock-auto-select-face nil
 139   "Non-nil means highlighting commands do not prompt for the face to use.
 140 Instead, each hi-lock command will cycle through the faces in
 141 `hi-lock-face-defaults'."
 142   :type 'boolean
 143   :version "24.4")
 144
 145 (defgroup hi-lock-faces nil
 146   "Faces for hi-lock."
 147   :group 'hi-lock
 148   :group 'faces)
 149
 150 (defface hi-yellow
 151   '((((min-colors 88) (background dark))
 152      (:background "yellow1" :foreground "black"))
 153     (((background dark)) (:background "yellow" :foreground "black"))
 154     (((min-colors 88)) (:background "yellow1"))
 155     (t (:background "yellow")))
 156   "Default face for hi-lock mode."
 157   :group 'hi-lock-faces)
 158
 159 (defface hi-pink
 160   '((((background dark)) (:background "pink" :foreground "black"))
 161     (t (:background "pink")))
 162   "Face for hi-lock mode."
 163   :group 'hi-lock-faces)
 164
 165 (defface hi-green
 166   '((((min-colors 88) (background dark))
 167      (:background "light green" :foreground "black"))
 168     (((background dark)) (:background "green" :foreground "black"))
 169     (((min-colors 88)) (:background "light green"))
 170     (t (:background "green")))
 171   "Face for hi-lock mode."
 172   :group 'hi-lock-faces)
 173
 174 (defface hi-blue
 175   '((((background dark)) (:background "light blue" :foreground "black"))
 176     (t (:background "light blue")))
 177   "Face for hi-lock mode."
 178   :group 'hi-lock-faces)
 179
 180 (defface hi-black-b
 181   '((t (:weight bold)))
 182   "Face for hi-lock mode."
 183   :group 'hi-lock-faces)
 184
 185 (defface hi-blue-b
 186   '((((min-colors 88)) (:weight bold :foreground "blue1"))
 187     (t (:weight bold :foreground "blue")))
 188   "Face for hi-lock mode."
 189   :group 'hi-lock-faces)
 190
 191 (defface hi-green-b
 192   '((((min-colors 88)) (:weight bold :foreground "green1"))
 193     (t (:weight bold :foreground "green")))
 194   "Face for hi-lock mode."
 195   :group 'hi-lock-faces)
 196
 197 (defface hi-red-b
 198   '((((min-colors 88)) (:weight bold :foreground "red1"))
 199     (t (:weight bold :foreground "red")))
 200   "Face for hi-lock mode."
 201   :group 'hi-lock-faces)
 202
 203 (defface hi-black-hb
 204   '((t (:weight bold :height 1.67 :inherit variable-pitch)))
 205   "Face for hi-lock mode."
 206   :group 'hi-lock-faces)
 207
 208 (defvar-local hi-lock-file-patterns nil
 209   "Patterns found in file for hi-lock.  Should not be changed.")
 210 (put 'hi-lock-file-patterns 'permanent-local t)
 211
 212 (defvar-local hi-lock-interactive-patterns nil
 213   "Patterns provided to hi-lock by user.  Should not be changed.")
 214 (put 'hi-lock-interactive-patterns 'permanent-local t)
 215
 216 (define-obsolete-variable-alias 'hi-lock-face-history
 217                                 'hi-lock-face-defaults "23.1")
 218 (defvar hi-lock-face-defaults
 219   '("hi-yellow" "hi-pink" "hi-green" "hi-blue" "hi-black-b"
 220     "hi-blue-b" "hi-red-b" "hi-green-b" "hi-black-hb")
 221   "Default faces for hi-lock interactive functions.")
 222
 223 (define-obsolete-variable-alias 'hi-lock-regexp-history
 224                                 'regexp-history
 225                                 "23.1")
 226
 227 (defvar hi-lock-file-patterns-prefix "Hi-lock"
 228   "Search target for finding hi-lock patterns at top of file.")
 229
 230 (defvar hi-lock-archaic-interface-message-used nil
 231   "True if user alerted that `global-hi-lock-mode' is now the global switch.
 232 Earlier versions of hi-lock used `hi-lock-mode' as the global switch;
 233 the message is issued if it appears that `hi-lock-mode' is used assuming
 234 that older functionality.  This variable avoids multiple reminders.")
 235
 236 (defvar hi-lock-archaic-interface-deduce nil
 237   "If non-nil, sometimes assume that `hi-lock-mode' means `global-hi-lock-mode'.
 238 Assumption is made if `hi-lock-mode' used in the *scratch* buffer while
 239 a library is being loaded.")
 240
 241 (defvar hi-lock-menu
 242   (let ((map (make-sparse-keymap "Hi Lock")))
 243     (define-key-after map [highlight-regexp]
 244       '(menu-item "Highlight Regexp..." highlight-regexp
 245         :help "Highlight text matching PATTERN (a regexp)."))
 246
 247     (define-key-after map [highlight-phrase]
 248       '(menu-item "Highlight Phrase..." highlight-phrase
 249         :help "Highlight text matching PATTERN (a regexp processed to match phrases)."))
 250
 251     (define-key-after map [highlight-lines-matching-regexp]
 252       '(menu-item "Highlight Lines..." highlight-lines-matching-regexp
 253         :help "Highlight lines containing match of PATTERN (a regexp)."))
 254
 255     (define-key-after map [highlight-symbol-at-point]
 256       '(menu-item "Highlight Symbol at Point" highlight-symbol-at-point
 257         :help "Highlight symbol found near point without prompting."))
 258
 259     (define-key-after map [unhighlight-regexp]
 260       '(menu-item "Remove Highlighting..." unhighlight-regexp
 261         :help "Remove previously entered highlighting pattern."
 262         :enable hi-lock-interactive-patterns))
 263
 264     (define-key-after map [hi-lock-write-interactive-patterns]
 265       '(menu-item "Patterns to Buffer" hi-lock-write-interactive-patterns
 266         :help "Insert interactively added REGEXPs into buffer at point."
 267         :enable hi-lock-interactive-patterns))
 268
 269     (define-key-after map [hi-lock-find-patterns]
 270       '(menu-item "Patterns from Buffer" hi-lock-find-patterns
 271         :help "Use patterns (if any) near top of buffer."))
 272     map)
 273   "Menu for hi-lock mode.")
 274
 275 (defvar hi-lock-map
 276   (let ((map (make-sparse-keymap "Hi Lock")))
 277     (define-key map "\C-xwi" 'hi-lock-find-patterns)
 278     (define-key map "\C-xwl" 'highlight-lines-matching-regexp)
 279     (define-key map "\C-xwp" 'highlight-phrase)
 280     (define-key map "\C-xwh" 'highlight-regexp)
 281     (define-key map "\C-xw." 'highlight-symbol-at-point)
 282     (define-key map "\C-xwr" 'unhighlight-regexp)
 283     (define-key map "\C-xwb" 'hi-lock-write-interactive-patterns)
 284     map)
 285   "Key map for hi-lock.")
 286
 287 ;; Visible Functions
 288
 289 ;;;###autoload
 290 (define-minor-mode hi-lock-mode
 291   "Toggle selective highlighting of patterns (Hi Lock mode).
 292 With a prefix argument ARG, enable Hi Lock mode if ARG is
 293 positive, and disable it otherwise.  If called from Lisp, enable
 294 the mode if ARG is omitted or nil.
 295
 296 Hi Lock mode is automatically enabled when you invoke any of the
 297 highlighting commands listed below, such as \\[highlight-regexp].
 298 To enable Hi Lock mode in all buffers, use `global-hi-lock-mode'
 299 or add (global-hi-lock-mode 1) to your init file.
 300
 301 In buffers where Font Lock mode is enabled, patterns are
 302 highlighted using font lock.  In buffers where Font Lock mode is
 303 disabled, patterns are applied using overlays; in this case, the
 304 highlighting will not be updated as you type.
 305
 306 When Hi Lock mode is enabled, a \"Regexp Highlighting\" submenu
 307 is added to the \"Edit\" menu.  The commands in the submenu,
 308 which can be called interactively, are:
 309
 310 \\[highlight-regexp] REGEXP FACE
 311   Highlight matches of pattern REGEXP in current buffer with FACE.
 312
 313 \\[highlight-phrase] PHRASE FACE
 314   Highlight matches of phrase PHRASE in current buffer with FACE.
 315   (PHRASE can be any REGEXP, but spaces will be replaced by matches
 316   to whitespace and initial lower-case letters will become case insensitive.)
 317
 318 \\[highlight-lines-matching-regexp] REGEXP FACE
 319   Highlight lines containing matches of REGEXP in current buffer with FACE.
 320
 321 \\[highlight-symbol-at-point]
 322   Highlight the symbol found near point without prompting, using the next
 323   available face automatically.
 324
 325 \\[unhighlight-regexp] REGEXP
 326   Remove highlighting on matches of REGEXP in current buffer.
 327
 328 \\[hi-lock-write-interactive-patterns]
 329   Write active REGEXPs into buffer as comments (if possible).  They may
 330   be read the next time file is loaded or when the \\[hi-lock-find-patterns] command
 331   is issued.  The inserted regexps are in the form of font lock keywords.
 332   (See `font-lock-keywords'.)  They may be edited and re-loaded with \\[hi-lock-find-patterns],
 333   any valid `font-lock-keywords' form is acceptable.  When a file is
 334   loaded the patterns are read if `hi-lock-file-patterns-policy' is
 335   'ask and the user responds y to the prompt, or if
 336   `hi-lock-file-patterns-policy' is bound to a function and that
 337   function returns t.
 338
 339 \\[hi-lock-find-patterns]
 340   Re-read patterns stored in buffer (in the format produced by \\[hi-lock-write-interactive-patterns]).
 341
 342 When hi-lock is started and if the mode is not excluded or patterns
 343 rejected, the beginning of the buffer is searched for lines of the
 344 form:
 345   Hi-lock: FOO
 346
 347 where FOO is a list of patterns.  The patterns must start before
 348 position \(number of characters into buffer)
 349 `hi-lock-file-patterns-range'.  Patterns will be read until
 350 Hi-lock: end is found.  A mode is excluded if it's in the list
 351 `hi-lock-exclude-modes'."
 352   :group 'hi-lock
 353   :lighter (:eval (if (or hi-lock-interactive-patterns
 354                           hi-lock-file-patterns)
 355                       " Hi" ""))
 356   :global nil
 357   :keymap hi-lock-map
 358   (when (and (equal (buffer-name) "*scratch*")
 359              load-in-progress
 360              (not (called-interactively-p 'interactive))
 361              (not hi-lock-archaic-interface-message-used))
 362     (setq hi-lock-archaic-interface-message-used t)
 363     (if hi-lock-archaic-interface-deduce
 364         (global-hi-lock-mode hi-lock-mode)
 365       (warn "%s"
 366        "Possible archaic use of (hi-lock-mode).
 367 Use (global-hi-lock-mode 1) in .emacs to enable hi-lock for all buffers,
 368 use (hi-lock-mode 1) for individual buffers.  For compatibility with Emacs
 369 versions before 22 use the following in your init file:
 370
 371         (if (functionp 'global-hi-lock-mode)
 372             (global-hi-lock-mode 1)
 373           (hi-lock-mode 1))
 374 ")))
 375   (if hi-lock-mode
 376       ;; Turned on.
 377       (progn
 378         (define-key-after menu-bar-edit-menu [hi-lock]
 379           (cons "Regexp Highlighting" hi-lock-menu))
 380         (hi-lock-find-patterns)
 381         (add-hook 'font-lock-mode-hook 'hi-lock-font-lock-hook nil t)
 382         ;; Remove regexps from font-lock-keywords (bug#13891).
 383         (add-hook 'change-major-mode-hook (lambda () (hi-lock-mode -1)) nil t))
 384     ;; Turned off.
 385     (when (or hi-lock-interactive-patterns
 386               hi-lock-file-patterns)
 387       (when hi-lock-interactive-patterns
 388         (font-lock-remove-keywords nil hi-lock-interactive-patterns)
 389         (setq hi-lock-interactive-patterns nil))
 390       (when hi-lock-file-patterns
 391         (font-lock-remove-keywords nil hi-lock-file-patterns)
 392         (setq hi-lock-file-patterns nil))
 393       (remove-overlays nil nil 'hi-lock-overlay t)
 394       (font-lock-flush))
 395     (define-key-after menu-bar-edit-menu [hi-lock] nil)
 396     (remove-hook 'font-lock-mode-hook 'hi-lock-font-lock-hook t)))
 397
 398 ;;;###autoload
 399 (define-globalized-minor-mode global-hi-lock-mode
 400   hi-lock-mode turn-on-hi-lock-if-enabled
 401   :group 'hi-lock)
 402
 403 (defun turn-on-hi-lock-if-enabled ()
 404   (setq hi-lock-archaic-interface-message-used t)
 405   (unless (memq major-mode hi-lock-exclude-modes)
 406     (hi-lock-mode 1)))
 407
 408 ;;;###autoload
 409 (defalias 'highlight-lines-matching-regexp 'hi-lock-line-face-buffer)
 410 ;;;###autoload
 411 (defun hi-lock-line-face-buffer (regexp &optional face)
 412   "Set face of all lines containing a match of REGEXP to FACE.
 413 Interactively, prompt for REGEXP using `read-regexp', then FACE.
 414 Use the global history list for FACE.
 415
 416 Use Font lock mode, if enabled, to highlight REGEXP.  Otherwise,
 417 use overlays for highlighting.  If overlays are used, the
 418 highlighting will not update as you type."
 419   (interactive
 420    (list
 421     (hi-lock-regexp-okay
 422      (read-regexp "Regexp to highlight line" 'regexp-history-last))
 423     (hi-lock-read-face-name)))
 424   (or (facep face) (setq face 'hi-yellow))
 425   (unless hi-lock-mode (hi-lock-mode 1))
 426   (hi-lock-set-pattern
 427    ;; The \\(?:...\\) grouping construct ensures that a leading ^, +, * or ?
 428    ;; or a trailing $ in REGEXP will be interpreted correctly.
 429    (concat "^.*\\(?:" regexp "\\).*$") face))
 430
 431
 432 ;;;###autoload
 433 (defalias 'highlight-regexp 'hi-lock-face-buffer)
 434 ;;;###autoload
 435 (defun hi-lock-face-buffer (regexp &optional face)
 436   "Set face of each match of REGEXP to FACE.
 437 Interactively, prompt for REGEXP using `read-regexp', then FACE.
 438 Use the global history list for FACE.
 439
 440 Use Font lock mode, if enabled, to highlight REGEXP.  Otherwise,
 441 use overlays for highlighting.  If overlays are used, the
 442 highlighting will not update as you type."
 443   (interactive
 444    (list
 445     (hi-lock-regexp-okay
 446      (read-regexp "Regexp to highlight" 'regexp-history-last))
 447     (hi-lock-read-face-name)))
 448   (or (facep face) (setq face 'hi-yellow))
 449   (unless hi-lock-mode (hi-lock-mode 1))
 450   (hi-lock-set-pattern regexp face))
 451
 452 ;;;###autoload
 453 (defalias 'highlight-phrase 'hi-lock-face-phrase-buffer)
 454 ;;;###autoload
 455 (defun hi-lock-face-phrase-buffer (regexp &optional face)
 456   "Set face of each match of phrase REGEXP to FACE.
 457 Interactively, prompt for REGEXP using `read-regexp', then FACE.
 458 Use the global history list for FACE.
 459
 460 When called interactively, replace whitespace in user-provided
 461 regexp with arbitrary whitespace, and make initial lower-case
 462 letters case-insensitive, before highlighting with `hi-lock-set-pattern'.
 463
 464 Use Font lock mode, if enabled, to highlight REGEXP.  Otherwise,
 465 use overlays for highlighting.  If overlays are used, the
 466 highlighting will not update as you type."
 467   (interactive
 468    (list
 469     (hi-lock-regexp-okay
 470      (hi-lock-process-phrase
 471       (read-regexp "Phrase to highlight" 'regexp-history-last)))
 472     (hi-lock-read-face-name)))
 473   (or (facep face) (setq face 'hi-yellow))
 474   (unless hi-lock-mode (hi-lock-mode 1))
 475   (hi-lock-set-pattern regexp face))
 476
 477 ;;;###autoload
 478 (defalias 'highlight-symbol-at-point 'hi-lock-face-symbol-at-point)
 479 ;;;###autoload
 480 (defun hi-lock-face-symbol-at-point ()
 481   "Highlight each instance of the symbol at point.
 482 Uses the next face from `hi-lock-face-defaults' without prompting,
 483 unless you use a prefix argument.
 484 Uses `find-tag-default-as-symbol-regexp' to retrieve the symbol at point.
 485
 486 This uses Font lock mode if it is enabled; otherwise it uses overlays,
 487 in which case the highlighting will not update as you type."
 488   (interactive)
 489   (let* ((regexp (hi-lock-regexp-okay
 490                   (find-tag-default-as-symbol-regexp)))
 491          (hi-lock-auto-select-face t)
 492          (face (hi-lock-read-face-name)))
 493     (or (facep face) (setq face 'hi-yellow))
 494     (unless hi-lock-mode (hi-lock-mode 1))
 495     (hi-lock-set-pattern regexp face)))
 496
 497 (defun hi-lock-keyword->face (keyword)
 498   (cadr (cadr (cadr keyword))))    ; Keyword looks like (REGEXP (0 'FACE) ...).
 499
 500 (declare-function x-popup-menu "menu.c" (position menu))
 501
 502 (defun hi-lock--regexps-at-point ()
 503   (let ((regexps '()))
 504     ;; When using overlays, there is no ambiguity on the best
 505     ;; choice of regexp.
 506     (let ((regexp (get-char-property (point) 'hi-lock-overlay-regexp)))
 507       (when regexp (push regexp regexps)))
 508     ;; With font-locking on, check if the cursor is on a highlighted text.
 509     (let ((face-after (get-text-property (point) 'face))
 510           (face-before
 511            (unless (bobp) (get-text-property (1- (point)) 'face)))
 512           (faces (mapcar #'hi-lock-keyword->face
 513                          hi-lock-interactive-patterns)))
 514       (unless (memq face-before faces) (setq face-before nil))
 515       (unless (memq face-after faces) (setq face-after nil))
 516       (when (and face-before face-after (not (eq face-before face-after)))
 517         (setq face-before nil))
 518       (when (or face-after face-before)
 519         (let* ((hi-text
 520                 (buffer-substring-no-properties
 521                  (if face-before
 522                      (or (previous-single-property-change (point) 'face)
 523                          (point-min))
 524                    (point))
 525                  (if face-after
 526                      (or (next-single-property-change (point) 'face)
 527                          (point-max))
 528                    (point)))))
 529           ;; Compute hi-lock patterns that match the
 530           ;; highlighted text at point.  Use this later in
 531           ;; during completing-read.
 532           (dolist (hi-lock-pattern hi-lock-interactive-patterns)
 533             (let ((regexp (car hi-lock-pattern)))
 534               (if (string-match regexp hi-text)
 535                   (push regexp regexps)))))))
 536     regexps))
 537
 538 (defvar-local hi-lock--unused-faces nil
 539   "List of faces that is not used and is available for highlighting new text.
 540 Face names from this list come from `hi-lock-face-defaults'.")
 541
 542 ;;;###autoload
 543 (defalias 'unhighlight-regexp 'hi-lock-unface-buffer)
 544 ;;;###autoload
 545 (defun hi-lock-unface-buffer (regexp)
 546   "Remove highlighting of each match to REGEXP set by hi-lock.
 547 Interactively, prompt for REGEXP, accepting only regexps
 548 previously inserted by hi-lock interactive functions.
 549 If REGEXP is t (or if \\[universal-argument] was specified interactively),
 550 then remove all hi-lock highlighting."
 551   (interactive
 552    (cond
 553     (current-prefix-arg (list t))
 554     ((and (display-popup-menus-p)
 555           (listp last-nonmenu-event)
 556           use-dialog-box)
 557      (catch 'snafu
 558        (or
 559         (x-popup-menu
 560          t
 561          (cons
 562           `keymap
 563           (cons "Select Pattern to Unhighlight"
 564                 (mapcar (lambda (pattern)
 565                           (list (car pattern)
 566                                 (format
 567                                  "%s (%s)" (car pattern)
 568                                  (hi-lock-keyword->face pattern))
 569                                 (cons nil nil)
 570                                 (car pattern)))
 571                         hi-lock-interactive-patterns))))
 572         ;; If the user clicks outside the menu, meaning that they
 573         ;; change their mind, x-popup-menu returns nil, and
 574         ;; interactive signals a wrong number of arguments error.
 575         ;; To prevent that, we return an empty string, which will
 576         ;; effectively disable the rest of the function.
 577         (throw 'snafu '("")))))
 578     (t
 579      ;; Un-highlighting triggered via keyboard action.
 580      (unless hi-lock-interactive-patterns
 581        (error "No highlighting to remove"))
 582      ;; Infer the regexp to un-highlight based on cursor position.
 583      (let* ((defaults (or (hi-lock--regexps-at-point)
 584                           (mapcar #'car hi-lock-interactive-patterns))))
 585        (list
 586         (completing-read (if (null defaults)
 587                              "Regexp to unhighlight: "
 588                            (format "Regexp to unhighlight (default %s): "
 589                                    (car defaults)))
 590                          hi-lock-interactive-patterns
 591                          nil t nil nil defaults))))))
 592   (dolist (keyword (if (eq regexp t) hi-lock-interactive-patterns
 593                      (list (assoc regexp hi-lock-interactive-patterns))))
 594     (when keyword
 595       (let ((face (hi-lock-keyword->face keyword)))
 596         ;; Make `face' the next one to use by default.
 597         (when (symbolp face)          ;Don't add it if it's a list (bug#13297).
 598           (add-to-list 'hi-lock--unused-faces (face-name face))))
 599       ;; FIXME: Calling `font-lock-remove-keywords' causes
 600       ;; `font-lock-specified-p' to go from nil to non-nil (because it
 601       ;; calls font-lock-set-defaults).  This is yet-another bug in
 602       ;; font-lock-add/remove-keywords, which we circumvent here by
 603       ;; testing `font-lock-fontified' (bug#19796).
 604       (if font-lock-fontified (font-lock-remove-keywords nil (list keyword)))
 605       (setq hi-lock-interactive-patterns
 606             (delq keyword hi-lock-interactive-patterns))
 607       (remove-overlays
 608        nil nil 'hi-lock-overlay-regexp (hi-lock--hashcons (car keyword)))
 609       (font-lock-flush))))
 610
 611 ;;;###autoload
 612 (defun hi-lock-write-interactive-patterns ()
 613   "Write interactively added patterns, if any, into buffer at point.
 614
 615 Interactively added patterns are those normally specified using
 616 `highlight-regexp' and `highlight-lines-matching-regexp'; they can
 617 be found in variable `hi-lock-interactive-patterns'."
 618   (interactive)
 619   (if (null hi-lock-interactive-patterns)
 620       (error "There are no interactive patterns"))
 621   (let ((beg (point)))
 622     (mapc
 623      (lambda (pattern)
 624        (insert (format "%s: (%s)\n"
 625                        hi-lock-file-patterns-prefix
 626                        (prin1-to-string pattern))))
 627      hi-lock-interactive-patterns)
 628     (comment-region beg (point)))
 629   (when (> (point) hi-lock-file-patterns-range)
 630     (warn "Inserted keywords not close enough to top of file")))
 631
 632 ;; Implementation Functions
 633
 634 (defun hi-lock-process-phrase (phrase)
 635   "Convert regexp PHRASE to a regexp that matches phrases.
 636
 637 Blanks in PHRASE replaced by regexp that matches arbitrary whitespace
 638 and initial lower-case letters made case insensitive."
 639   (let ((mod-phrase nil))
 640     ;; FIXME fragile; better to just bind case-fold-search?  (Bug#7161)
 641     (setq mod-phrase
 642           (replace-regexp-in-string
 643            "\\(^\\|\\s-\\)\\([a-z]\\)"
 644            (lambda (m) (format "%s[%s%s]"
 645                                (match-string 1 m)
 646                                (upcase (match-string 2 m))
 647                                (match-string 2 m))) phrase))
 648     ;; FIXME fragile; better to use search-spaces-regexp?
 649     (setq mod-phrase
 650           (replace-regexp-in-string
 651            "\\s-+" "[ \t\n]+" mod-phrase nil t))))
 652
 653 (defun hi-lock-regexp-okay (regexp)
 654   "Return REGEXP if it appears suitable for a font-lock pattern.
 655
 656 Otherwise signal an error.  A pattern that matches the null string is
 657 not suitable."
 658   (cond
 659    ((null regexp)
 660     (error "Regexp cannot match nil"))
 661    ((string-match regexp "")
 662     (error "Regexp cannot match an empty string"))
 663    (t regexp)))
 664
 665 (defun hi-lock-read-face-name ()
 666   "Return face for interactive highlighting.
 667 When `hi-lock-auto-select-face' is non-nil, just return the next face.
 668 Otherwise, or with a prefix argument, read a face from the minibuffer
 669 with completion and history."
 670   (unless hi-lock-interactive-patterns
 671     (setq hi-lock--unused-faces hi-lock-face-defaults))
 672   (let* ((last-used-face
 673           (when hi-lock-interactive-patterns
 674             (face-name (hi-lock-keyword->face
 675                         (car hi-lock-interactive-patterns)))))
 676          (defaults (append hi-lock--unused-faces
 677                            (cdr (member last-used-face hi-lock-face-defaults))
 678                            hi-lock-face-defaults))
 679          face)
 680           (if (and hi-lock-auto-select-face (not current-prefix-arg))
 681         (setq face (or (pop hi-lock--unused-faces) (car defaults)))
 682       (setq face (completing-read
 683                   (format "Highlight using face (default %s): "
 684                           (car defaults))
 685                   obarray 'facep t nil 'face-name-history defaults))
 686       ;; Update list of un-used faces.
 687       (setq hi-lock--unused-faces (remove face hi-lock--unused-faces))
 688       ;; Grow the list of defaults.
 689       (add-to-list 'hi-lock-face-defaults face t))
 690     (intern face)))
 691
 692 (defun hi-lock-set-pattern (regexp face)
 693   "Highlight REGEXP with face FACE."
 694   ;; Hashcons the regexp, so it can be passed to remove-overlays later.
 695   (setq regexp (hi-lock--hashcons regexp))
 696   (let ((pattern (list regexp (list 0 (list 'quote face) 'prepend))))
 697     ;; Refuse to highlight a text that is already highlighted.
 698     (unless (assoc regexp hi-lock-interactive-patterns)
 699       (push pattern hi-lock-interactive-patterns)
 700       (if (and font-lock-mode (font-lock-specified-p major-mode))
 701           (progn
 702             (font-lock-add-keywords nil (list pattern) t)
 703             (font-lock-flush))
 704         (let* ((range-min (- (point) (/ hi-lock-highlight-range 2)))
 705                (range-max (+ (point) (/ hi-lock-highlight-range 2)))
 706                (search-start
 707                 (max (point-min)
 708                      (- range-min (max 0 (- range-max (point-max))))))
 709                (search-end
 710                 (min (point-max)
 711                      (+ range-max (max 0 (- (point-min) range-min))))))
 712           (save-excursion
 713             (goto-char search-start)
 714             (while (re-search-forward regexp search-end t)
 715               (let ((overlay (make-overlay (match-beginning 0) (match-end 0))))
 716                 (overlay-put overlay 'hi-lock-overlay t)
 717                 (overlay-put overlay 'hi-lock-overlay-regexp regexp)
 718                 (overlay-put overlay 'face face))
 719               (goto-char (match-end 0)))))))))
 720
 721 (defun hi-lock-set-file-patterns (patterns)
 722   "Replace file patterns list with PATTERNS and refontify."
 723   (when (or hi-lock-file-patterns patterns)
 724     (font-lock-remove-keywords nil hi-lock-file-patterns)
 725     (setq hi-lock-file-patterns patterns)
 726     (font-lock-add-keywords nil hi-lock-file-patterns t)
 727     (font-lock-flush)))
 728
 729 (defun hi-lock-find-patterns ()
 730   "Find patterns in current buffer for hi-lock."
 731   (interactive)
 732   (unless (memq major-mode hi-lock-exclude-modes)
 733     (let ((all-patterns nil)
 734           (target-regexp (concat "\\<" hi-lock-file-patterns-prefix ":")))
 735       (save-excursion
 736         (save-restriction
 737           (widen)
 738           (goto-char (point-min))
 739           (re-search-forward target-regexp
 740                              (+ (point) hi-lock-file-patterns-range) t)
 741           (beginning-of-line)
 742           (while (and (re-search-forward target-regexp (+ (point) 100) t)
 743                       (not (looking-at "\\s-*end")))
 744             (condition-case nil
 745                 (setq all-patterns (append (read (current-buffer)) all-patterns))
 746               (error (message "Invalid pattern list expression at %d"
 747                               (line-number-at-pos)))))))
 748       (when (and all-patterns
 749                  hi-lock-mode
 750                  (cond
 751                   ((eq this-command 'hi-lock-find-patterns) t)
 752                   ((functionp hi-lock-file-patterns-policy)
 753                    (funcall hi-lock-file-patterns-policy all-patterns))
 754                   ((eq hi-lock-file-patterns-policy 'ask)
 755                    (y-or-n-p "Add patterns from this buffer to hi-lock? "))
 756                   (t nil)))
 757         (hi-lock-set-file-patterns all-patterns)
 758         (if (called-interactively-p 'interactive)
 759             (message "Hi-lock added %d patterns." (length all-patterns)))))))
 760
 761 (defun hi-lock-font-lock-hook ()
 762   "Add hi-lock patterns to font-lock's."
 763   (when font-lock-fontified
 764     (font-lock-add-keywords nil hi-lock-file-patterns t)
 765     (font-lock-add-keywords nil hi-lock-interactive-patterns t)))
 766
 767 (defvar hi-lock--hashcons-hash
 768   (make-hash-table :test 'equal :weakness t)
 769   "Hash table used to hash cons regexps.")
 770
 771 (defun hi-lock--hashcons (string)
 772   "Return unique object equal to STRING."
 773   (or (gethash string hi-lock--hashcons-hash)
 774       (puthash string string hi-lock--hashcons-hash)))
 775
 776 (defun hi-lock-unload-function ()
 777   "Unload the Hi-Lock library."
 778   (global-hi-lock-mode -1)
 779   ;; continue standard unloading
 780   nil)
 781
 782 (provide 'hi-lock)
 783
 784 ;;; hi-lock.el ends here