1 ;;; generic.el --- Defining simple major modes with comment and font-lock.
3 ;; Copyright (C) 1997 Free Software Foundation, Inc.
5 ;; Author: Peter Breton <pbreton@cs.umb.edu>
6 ;; Created: Fri Sep 27 1996
7 ;; Keywords: generic, comment, font-lock
9 ;; This file is part of GNU Emacs.
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)
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.
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.
28 ;; Meta-mode to create simple major modes
29 ;; with basic comment and font-lock support
35 ;; Generic-mode is a meta-mode which can be used to define small modes
36 ;; which provide basic comment and font-lock support. These modes are
37 ;; intended for the many configuration files and such which are too small
38 ;; for a "real" mode, but still have a regular syntax, comment characters
41 ;; Each generic mode can define the following:
43 ;; * List of comment-characters. The entries in this list should be
44 ;; either a character, a one or two character string or a cons pair.
45 ;; If the entry is a character or a one-character string
46 ;; LIMITATIONS: Emacs does not support comment strings of more than
47 ;; two characters in length.
49 ;; * List of keywords to font-lock. Each keyword should be a string.
50 ;; If you have additional keywords which should be highlighted in a face
51 ;; different from `font-lock-keyword-face', you can use the convenience
52 ;; function `generic-make-keywords-list' (which see), and add the
53 ;; result to the following list:
55 ;; * Additional expressions to font-lock. This should be a list of
56 ;; expressions, each of which should be of the same form
57 ;; as those in `font-lock-defaults-alist'.
59 ;; * List of regular expressions to be placed in auto-mode-alist.
61 ;; * List of functions to call to do some additional setup
63 ;; This should pretty much cover basic functionality; if you need much
64 ;; more than this, or you find yourself writing extensive customizations,
65 ;; perhaps you should be writing a major mode instead!
69 ;; To put a file into generic mode using local variables, use a line
70 ;; like this in a Local Variables block:
72 ;; mode: default-generic
74 ;; Do NOT use "mode: generic"!
75 ;; See also "AUTOMATICALLY ENTERING GENERIC MODE" below.
77 ;; DEFINING NEW GENERIC MODES:
79 ;; Use the `define-generic-mode' function to define new modes.
83 ;; (define-generic-mode 'foo-generic-mode
88 ;; (list 'foo-setup-function))
90 ;; defines a new generic-mode `foo-generic-mode', which has '%' as a
91 ;; comment character, and "keyword" as a keyword. When files which end in
92 ;; '.FOO' are loaded, Emacs will go into foo-generic-mode and call
93 ;; foo-setup-function. You can also use the function `foo-generic-mode'
94 ;; (which is interactive) to put a buffer into foo-generic-mode.
96 ;; AUTOMATICALLY ENTERING GENERIC MODE:
98 ;; Generic-mode provides a hook which automatically puts a
99 ;; file into default-generic-mode if the first few lines of a file in
100 ;; fundamental mode start with a hash comment character. To disable
101 ;; this functionality, set the variable `generic-use-find-file-hook'
102 ;; to nil BEFORE loading generic-mode. See the variables
103 ;; `generic-lines-to-scan' and `generic-find-file-regexp' for customization
108 ;; Be careful that your font-lock definitions are correct. Getting them
109 ;; wrong can cause emacs to continually attempt to fontify! This problem
110 ;; is not specific to generic-mode.
113 ;; Credit for suggestions, brainstorming, help with debugging:
114 ;; ACorreir@pervasive-sw.com (Alfred Correira)
118 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
119 ;; Internal Variables
120 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
122 (make-variable-buffer-local
123 (defvar generic-font-lock-defaults nil
124 "Global defaults for font-lock in a generic mode."))
126 (make-variable-buffer-local
127 (defvar generic-mode-name 'default-generic-mode
128 "The name of the generic mode.
129 This is the car of one of the items in `generic-mode-alist'.
130 This variable is buffer-local."))
132 (make-variable-buffer-local
133 (defvar generic-comment-list nil
134 "List of comment characters for a generic mode."))
136 (make-variable-buffer-local
137 (defvar generic-keywords-list nil
138 "List of keywords for a generic mode."))
140 (make-variable-buffer-local
141 (defvar generic-font-lock-expressions nil
142 "List of font-lock expressions for a generic mode."))
144 (make-variable-buffer-local
145 (defvar generic-mode-function-list nil
146 "List of customization functions to call for a generic mode."))
148 (make-variable-buffer-local
149 (defvar generic-mode-syntax-table nil
150 "Syntax table for use in a generic mode."))
152 (defvar generic-mode-alist nil
153 "An association list for generic-mode.
154 Each entry in the list looks like this:
156 NAME COMMENT-LIST KEYWORD-LIST FONT-LOCK-LIST AUTO-MODE-LIST FUNCTION-LIST.
158 Do not add entries to this list directly; use `define-generic-mode'
159 instead (which see).")
161 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
162 ;; Customization Variables
163 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
165 (defgroup generic nil
166 "Define simple major modes with comment and font-lock support."
170 (defcustom generic-use-find-file-hook t
171 "*If non-nil, add a hook to enter default-generic-mode automatically
172 if the first few lines of a file in fundamental mode start with a hash
178 (defcustom generic-lines-to-scan 3
179 "*Number of lines that `generic-mode-find-file-hook' looks at
180 when deciding whether to enter generic-mode automatically.
181 This variable should be set to a small positive number."
186 (defcustom generic-find-file-regexp "#.*\n\\(.*\n\\)?"
187 "*Regular expression used by `generic-mode-find-file-hook'
188 to determine if files in fundamental mode should be put into
189 `default-generic-mode' instead."
194 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
196 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
198 (defsubst generic-read-type ()
202 '(lambda (elt) (list (symbol-name (car elt))))
203 generic-mode-alist) nil t))
205 ;; Basic sanity checks. It does *not* check whether the elements of the lists
206 ;; are of the correct type.
207 (defsubst generic-mode-sanity-check (name comment-list keyword-list
208 font-lock-list auto-mode-list
209 function-list &optional description)
210 (and (not (symbolp name))
211 (error "%s is not a symbol" (princ name)))
213 (mapcar '(lambda (elt)
214 (if (not (listp elt))
215 (error "%s is not a list" (princ elt))))
216 (list comment-list keyword-list font-lock-list
217 auto-mode-list function-list))
219 (and (not (or (null description) (stringp description)))
220 (error "Description must be a string or nil"))
223 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
225 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
228 (defun define-generic-mode (name comment-list keyword-list font-lock-list
229 auto-mode-list function-list
230 &optional description)
231 "Create a new generic mode with NAME.
232 NAME should be a symbol; its string representation is used as the function
233 name. If DESCRIPTION is provided, it is used as the docstring for the new
236 COMMENT-LIST is a list, whose entries are either a single character,
237 a one or two character string or a cons pair. If the entry is a character
238 or a one-character string, it is added to the mode's syntax table with
239 comment-start syntax. If the entry is a cons pair, the elements of the
240 pair are considered to be comment-start and comment-end respectively.
241 Note that Emacs has limitations regarding comment characters.
243 KEYWORD-LIST is a list of keywords to highlight with `font-lock-keyword-face'.
244 Each keyword should be a string.
246 FONT-LOCK-LIST is a list of additional expressions to highlight. Each entry
247 in the list should have the same form as an entry in `font-lock-defaults-alist'
249 AUTO-MODE-LIST is a list of regular expressions to add to auto-mode-alist.
250 These regexps are added to auto-mode-alist as soon as `define-generic-mode'
251 is called; any old regexps with the same name are removed.
253 FUNCTION-LIST is a list of functions to call to do some additional setup.
255 See the file generic-x.el for some examples of `define-generic-mode'."
257 ;; Basic sanity check
258 (generic-mode-sanity-check name
259 comment-list keyword-list font-lock-list
260 auto-mode-list function-list description)
262 ;; Remove any old entry
263 (setq generic-mode-alist
264 (delq (assq name generic-mode-alist)
268 (setq generic-mode-alist
272 name comment-list keyword-list font-lock-list
273 auto-mode-list function-list
277 ;; Add it to auto-mode-alist
278 (generic-add-to-auto-mode name auto-mode-list t)
280 ;; Define a function for it
281 (generic-create-generic-function name description)
284 (defun generic-add-to-auto-mode (mode auto-mode-list
285 &optional remove-old prepend)
286 "Add the entries for mode to `auto-mode-alist'.
287 If remove-old is non-nil, removes old entries first. If prepend is
288 non-nil, prepends entries to auto-mode-alist; otherwise, appends them."
290 (if (not (listp auto-mode-list))
291 (error "%s is not a list" (princ auto-mode-list)))
293 (let ((new-mode (intern (symbol-name mode))))
295 (let ((auto-mode-entry))
296 (while (setq auto-mode-entry (rassq new-mode auto-mode-alist))
297 (setq auto-mode-alist
298 (delq auto-mode-entry
301 (mapcar '(lambda (entry)
302 (generic-add-auto-mode-entry new-mode entry prepend))
305 (defun generic-add-auto-mode-entry (name entry &optional prepend)
306 "Add a new entry to the end of auto-mode-alist.
307 If prepend is non-nil, add the entry to the front of the list."
308 (let ((new-entry (list (cons entry name))))
309 (setq auto-mode-alist
311 (append new-entry auto-mode-alist)
312 (append auto-mode-alist new-entry)))))
314 (defun generic-create-generic-function (name &optional description)
315 "Create a generic mode function with NAME.
316 If DESCRIPTION is provided, it is used as the docstring."
317 (let ((symname (symbol-name name)))
318 (fset (intern symname)
321 (concat "Generic mode for type " symname))
323 (list 'generic-mode-with-type (list 'quote name))))))
325 (defun generic-mode-with-type (&optional mode)
326 "Go into the generic-mode MODE."
327 (let* ((type (or mode generic-mode-name))
328 (generic-mode-list (assoc type generic-mode-alist))
331 (and (not generic-mode-list)
332 (error "Can't find generic-mode information for type %s"
333 (princ generic-mode-name)))
335 ;; Put this after the point where we read generic-mode-name!
336 (kill-all-local-variables)
339 generic-mode-name type
340 generic-comment-list (nth 1 generic-mode-list)
341 generic-keywords-list (nth 2 generic-mode-list)
342 generic-font-lock-expressions (nth 3 generic-mode-list)
343 generic-mode-function-list (nth 5 generic-mode-list)
345 mode-name (symbol-name type)
348 (generic-mode-set-comments generic-comment-list)
350 ;; Font-lock functionality
351 ;; Font-lock-defaults are always set even if there are no keywords
352 ;; or font-lock expressions, so comments can be highlighted.
353 (setq generic-font-lock-defaults nil)
354 (generic-mode-set-font-lock generic-keywords-list
355 generic-font-lock-expressions)
356 (make-local-variable 'font-lock-defaults)
357 (setq font-lock-defaults (list 'generic-font-lock-defaults nil))
359 ;; Call a list of functions
360 (and generic-mode-function-list
361 (mapcar 'funcall generic-mode-function-list))
366 (defun generic-mode (type)
367 "A mode to do basic comment and font-lock functionality
368 for files which are too small to warrant their own mode, but have
369 comment characters, keywords, and the like.
371 To define a generic-mode, use the function `define-generic-mode'.
372 Some generic modes are defined in `generic-x.el'."
374 (list (generic-read-type)))
375 (generic-mode-with-type (intern type)))
377 ;;; Comment Functionality
378 (defun generic-mode-set-comments (comment-list)
379 "Set up comment functionality for generic mode."
380 (if (null comment-list)
382 (let ((generic-mode-syntax-table (make-syntax-table)))
383 (make-local-variable 'comment-start)
384 (make-local-variable 'comment-start-skip)
385 (make-local-variable 'comment-end)
386 (mapcar 'generic-mode-set-a-comment comment-list)
387 (set-syntax-table generic-mode-syntax-table))))
389 (defun generic-mode-set-a-comment (comment)
390 (and (char-or-string-p comment)
391 (if (stringp comment)
393 ((eq (length comment) 1)
394 (generic-mode-set-comment-char
395 (string-to-char comment)))
396 ((eq (length comment) 2)
397 (generic-mode-set-comment-string comment))
399 (error "Character string %s must be one or two characters long"
402 (generic-mode-set-comment-char comment)))
404 (generic-mode-set-comment-pair comment)))
406 (defun generic-mode-set-comment-char (comment-char)
407 "Set the given character as a comment character for generic mode."
408 (if (not comment-char)
412 comment-start (char-to-string comment-char)
413 comment-start-skip (concat comment-start "+ *")
416 (modify-syntax-entry comment-char "<"
417 generic-mode-syntax-table)
418 (modify-syntax-entry ?\n ">"
419 generic-mode-syntax-table)))
421 (defun generic-mode-set-comment-string (comment-string)
422 "Set the given string as a comment string for generic mode."
423 (if (not comment-string)
427 comment-start comment-string
428 comment-start-skip (concat comment-start " *")
431 (let ((first (elt comment-string 0))
432 (second (elt comment-string 1)))
433 ;; C++ style comments
434 (if (char-equal first second)
436 (modify-syntax-entry first "<12b"
437 generic-mode-syntax-table)
438 (modify-syntax-entry ?\n ">b"
439 generic-mode-syntax-table)))
440 ;; Some other two character string
441 (modify-syntax-entry first "<1"
442 generic-mode-syntax-table)
443 (modify-syntax-entry second "<2"
444 generic-mode-syntax-table)
445 (modify-syntax-entry ?\n ">"
446 generic-mode-syntax-table))))
448 (defun generic-mode-set-comment-pair (comment-pair)
449 "Set the given comment pair as a comment start and end for generic mode."
450 (let ((generic-comment-start (car comment-pair))
451 (generic-comment-end (cdr comment-pair))
454 comment-end generic-comment-end
455 comment-start generic-comment-start
456 comment-start-skip (concat generic-comment-start " *")
460 (and (not (and (stringp generic-comment-start)
461 (stringp generic-comment-end)))
462 (error "Elements of cons pair must be strings"))
463 (and (not (and (equal (length generic-comment-start) 2)
464 (equal (length generic-comment-end) 2)))
465 (error "Start and end must be exactly two characters long"))
467 (let ((first (elt generic-comment-start 0))
468 (second (elt generic-comment-start 1))
469 (third (elt generic-comment-end 0))
470 (fourth (elt generic-comment-end 1))
473 (modify-syntax-entry first ". 1" generic-mode-syntax-table)
474 (modify-syntax-entry second ". 2" generic-mode-syntax-table)
481 ((char-equal first third) " 13")
482 ((char-equal second third) " 23")
485 generic-mode-syntax-table)
492 ((char-equal first fourth) " 14")
493 ((char-equal second fourth) " 24")
496 generic-mode-syntax-table)
499 (defun generic-mode-set-font-lock (keywords font-lock-expressions)
500 "Set up font-lock functionality for generic mode."
501 (let ((generic-font-lock-expressions))
505 generic-font-lock-expressions
507 (list (let ((regexp (regexp-opt keywords)))
508 (list (concat "\\<\\(" regexp "\\)\\>")
510 'font-lock-keyword-face)))
511 generic-font-lock-expressions)))
512 ;; Other font-lock expressions
513 (and font-lock-expressions
514 (setq generic-font-lock-expressions
516 font-lock-expressions
517 generic-font-lock-expressions)))
518 (and (or font-lock-expressions keywords)
519 (setq generic-font-lock-defaults generic-font-lock-expressions))
522 ;; Support for [KEYWORD] constructs found in INF, INI and Samba files
523 (defun generic-bracket-support ()
524 (setq imenu-generic-expression
525 '((nil "^\\[\\(.*\\)\\]" 1))
526 imenu-case-fold-search t))
528 ;; This generic mode is always defined
529 (define-generic-mode 'default-generic-mode (list ?#) nil nil nil nil)
531 ;; A more general solution would allow us to enter generic-mode for
532 ;; *any* comment character, but would require us to synthesize a new
533 ;; generic-mode on the fly. I think this gives us most of what we
535 (defun generic-mode-find-file-hook ()
536 "Hook to enter default-generic-mode automatically
537 if the first few lines of a file in fundamental-mode start with a hash
538 comment character. This hook will be installed if the variable
539 `generic-use-find-file-hook' is non-nil. The variable `generic-lines-to-scan'
540 determines the number of lines to look at."
541 (if (not (eq major-mode 'fundamental-mode))
543 (and (or (> 1 generic-lines-to-scan)
544 (< 50 generic-lines-to-scan))
545 (error "Variable `generic-lines-to-scan' should be set to a small"
547 (let ((comment-regexp "")
550 (while (< count generic-lines-to-scan)
551 (setq comment-regexp (concat comment-regexp
552 generic-find-file-regexp))
553 (setq count (1+ count)))
555 (goto-char (point-min))
556 (and (looking-at comment-regexp)
557 (generic-mode-with-type 'default-generic-mode))))))
559 (defun generic-mode-ini-file-find-file-hook ()
560 "Hook to enter default-generic-mode automatically
561 if the first few lines of a file in fundamental-mode look like an INI file.
562 This hook is NOT installed by default."
563 (and (eq major-mode 'fundamental-mode)
565 (goto-char (point-min))
566 (and (looking-at "^\\s-*\\[.*\\]")
567 (generic-mode-with-type 'ini-generic-mode)))))
569 (and generic-use-find-file-hook
570 (add-hook 'find-file-hooks 'generic-mode-find-file-hook))
572 (defun generic-make-keywords-list (keywords-list face &optional prefix suffix)
573 "Return a regular expression matching the specified keywords.
574 The regexp is highlighted with FACE."
575 (and (not (listp keywords-list))
576 (error "Keywords argument must be a list of strings"))
577 (list (concat (or prefix "")
579 ;; Use an optimized regexp.
580 (regexp-opt keywords-list t)
588 ;;; generic.el ends here