1 ;;; generic-mode.el --- A meta-mode which makes it easy to create small
2 ;; modes with basic comment and font-lock support
4 ;; Copyright (C) 1997 Free Software Foundation, Inc.
6 ;; Author: Peter Breton
7 ;; Created: Fri Sep 27 1996
8 ;; Keywords: generic, comment, font-lock
10 ;; This file is part of GNU Emacs.
12 ;; GNU Emacs is free software; you can redistribute it and/or modify
13 ;; it under the terms of the GNU General Public License as published by
14 ;; the Free Software Foundation; either version 2, or (at your option)
17 ;; GNU Emacs is distributed in the hope that it will be useful,
18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 ;; GNU General Public License for more details.
22 ;; You should have received a copy of the GNU General Public License
23 ;; along with GNU Emacs; see the file COPYING. If not, write to the
24 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
25 ;; Boston, MA 02111-1307, USA.
29 ;; Meta-mode to create simple major modes
30 ;; with basic comment and font-lock support
36 ;; Generic-mode is a meta-mode which can be used to define small modes
37 ;; which provide basic comment and font-lock support. These modes are
38 ;; intended for the many configuration files and such which are too small
39 ;; for a "real" mode, but still have a regular syntax, comment characters
42 ;; Each generic mode can define the following:
44 ;; * List of comment-characters. The entries in this list should be
45 ;; either a character, a one or two character string or a cons pair.
46 ;; If the entry is a character or a one-character string
47 ;; LIMITATIONS: Emacs does not support comment strings of more than
48 ;; two characters in length.
50 ;; * List of keywords to font-lock. Each keyword should be a string.
51 ;; If you have additional keywords which should be highlighted in a face
52 ;; different from 'font-lock-keyword-face', you can use the convenience
53 ;; function 'generic-make-keywords-list' (which see), and add the
54 ;; result to the following list:
56 ;; * Additional expressions to font-lock. This should be a list of
57 ;; expressions, each of which should be of the same form
58 ;; as those in 'font-lock-defaults-alist'.
60 ;; * List of regular expressions to be placed in auto-mode-alist.
62 ;; * List of functions to call to do some additional setup
64 ;; This should pretty much cover basic functionality; if you need much
65 ;; more than this, or you find yourself writing extensive customizations,
66 ;; perhaps you should be writing a major mode instead!
70 ;; To put a file into generic mode using local variables, use a line
71 ;; like this in a Local Variables block:
73 ;; mode: default-generic
75 ;; Do NOT use "mode: generic"!
76 ;; See also "AUTOMATICALLY ENTERING GENERIC MODE" below.
78 ;; DEFINING NEW GENERIC MODES:
80 ;; Use the 'define-generic-mode' function to define new modes.
83 ;; (require 'generic-mode)
84 ;; (define-generic-mode 'foo-generic-mode
89 ;; (list 'foo-setup-function))
91 ;; defines a new generic-mode 'foo-generic-mode', which has '%' as a
92 ;; comment character, and "keyword" as a keyword. When files which end in
93 ;; '.FOO' are loaded, Emacs will go into foo-generic-mode and call
94 ;; foo-setup-function. You can also use the function 'foo-generic-mode'
95 ;; (which is interactive) to put a buffer into foo-generic-mode.
97 ;; AUTOMATICALLY ENTERING GENERIC MODE:
99 ;; Generic-mode provides a hook which automatically puts a
100 ;; file into default-generic-mode if the first few lines of a file in
101 ;; fundamental mode start with a hash comment character. To disable
102 ;; this functionality, set the variable 'generic-use-find-file-hook'
103 ;; to nil BEFORE loading generic-mode. See the variables
104 ;; 'generic-lines-to-scan' and 'generic-find-file-regexp' for customization
109 ;; Be careful that your font-lock definitions are correct. Getting them
110 ;; wrong can cause emacs to continually attempt to fontify! This problem
111 ;; is not specific to generic-mode.
114 ;; Credit for suggestions, brainstorming, patches and bug-fixes:
115 ;; ACorreir@pervasive-sw.com (Alfred Correira)
118 ;; $Log: generic-mode.el,v $
119 ;; Revision 1.6 1996/11/01 17:27:47 peter
120 ;; Changed the function generic-function-name to return a string instead
121 ;; of a symbol. Generic-mode now uses this for the mode's name
123 ;; Revision 1.5 1996/11/01 16:45:20 peter
124 ;; Added GPL and LCD information.
125 ;; Updated documentation
126 ;; Added generic-find-file-regexp variable
127 ;; Added generic-make-keywords-list function
129 ;; Revision 1.4 1996/10/19 12:16:59 peter
130 ;; Small bug fixes: fontlock -> font-lock
131 ;; New entries are added to the end of auto-mode-alist
132 ;; Generic-font-lock-defaults are set to nil, not (list nil)
133 ;; Comment-regexp in generic-mode-find-file-hook changed to allow optional
136 ;; Revision 1.3 1996/10/17 08:24:25 peter
137 ;; Added generic-mode-find-file-hook and associated variables
139 ;; Revision 1.2 1996/10/17 01:00:45 peter
140 ;; Moved from a data-centered approach (generic-mode-alist) to
141 ;; a function-based one (define-generic-mode)
143 ;; Revision 1.1 1996/10/10 11:37:36 peter
149 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
151 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
153 (make-variable-buffer-local
154 (defvar generic-font-lock-defaults nil
155 "Global defaults for font-lock in a generic mode."))
157 (make-variable-buffer-local
158 (defvar generic-mode-name
'default-generic-mode
159 "The name of the generic mode.
160 This is the car of one of the items in `generic-mode-alist'.
161 This variable is buffer-local."))
163 (make-variable-buffer-local
164 (defvar generic-comment-list nil
165 "List of comment characters for a generic mode."))
167 (make-variable-buffer-local
168 (defvar generic-keywords-list nil
169 "List of keywords for a generic mode."))
171 (make-variable-buffer-local
172 (defvar generic-font-lock-expressions nil
173 "List of font-lock expressions for a generic mode."))
175 (make-variable-buffer-local
176 (defvar generic-mode-function-list nil
177 "List of customization functions to call for a generic mode."))
179 (make-variable-buffer-local
180 (defvar generic-mode-syntax-table nil
181 "Syntax table for use in a generic mode."))
183 (defvar generic-mode-alist nil
184 "An association list for generic-mode.
185 Each entry in the list looks like this:
187 NAME COMMENT-LIST KEYWORD-LIST FONT-LOCK-LIST AUTO-MODE-LIST FUNCTION-LIST.
189 Do not add entries to this list directly; use `define-generic-mode'
190 instead (which see).")
192 (defvar generic-use-find-file-hook t
193 "*If non-nil, add a hook to enter default-generic-mode automatically
194 if the first few lines of a file in fundamental mode start with a hash
197 (defvar generic-lines-to-scan
3
198 "*Number of lines that `generic-mode-find-file-hook' looks at
199 when deciding whether to enter generic-mode automatically.
200 This variable should be set to a small positive number.")
202 (defvar generic-find-file-regexp
"#.*\n\\(.*\n\\)?"
203 "*Regular expression used by `generic-mode-find-file-hook'
204 to determine if files in fundamental mode should be put into
205 `default-generic-mode' instead.")
207 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
209 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
211 (defsubst generic-read-type
()
215 '(lambda (elt) (list (symbol-name (car elt
))))
216 generic-mode-alist
) nil t
))
218 ;; Basic sanity checks. It does *not* check whether the elements of the lists
219 ;; are of the correct type.
220 (defsubst generic-mode-sanity-check
(name comment-list keyword-list
221 font-lock-list auto-mode-list
222 function-list
&optional description
)
223 (if (not (symbolp name
))
224 (error "%s is not a symbol" (princ name
)))
226 (mapcar '(lambda (elt)
227 (if (not (listp elt
))
228 (error "%s is not a list" (princ elt
))))
229 (list comment-list keyword-list font-lock-list
230 auto-mode-list function-list
))
232 (if (not (or (null description
) (stringp description
)))
233 (error "Description must be a string or nil"))
236 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
238 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
241 (defun define-generic-mode (name comment-list keyword-list font-lock-list
242 auto-mode-list function-list
243 &optional description
)
244 "Create a new generic mode with NAME.
245 NAME should be a symbol; its string representation is used as the function
246 name. If DESCRIPTION is provided, it is used as the docstring for the new
249 COMMENT-LIST is a list, whose entries are either a single character,
250 a one or two character string or a cons pair. If the entry is a character
251 or a one-character string, it is added to the mode's syntax table with
252 comment-start syntax. If the entry is a cons pair, the elements of the
253 pair are considered to be comment-start and comment-end respectively.
254 Note that Emacs has limitations regarding comment characters.
256 KEYWORD-LIST is a list of keywords to highlight with `font-lock-keyword-face'.
257 Each keyword should be a string.
259 FONT-LOCK-LIST is a list of additional expressions to highlight. Each entry
260 in the list should have the same form as an entry in `font-lock-defaults-alist'
262 AUTO-MODE-LIST is a list of regular expressions to add to auto-mode-alist.
263 These regexps are added to auto-mode-alist as soon as `define-generic-mode'
264 is called; any old regexps with the same name are removed. To modify the
265 auto-mode-alist expressions, use `alter-generic-mode-auto-mode' (which see).
267 FUNCTION-LIST is a list of functions to call to do some additional setup.
269 See the file generic-extras.el for some examples of `define-generic-mode'."
271 ;; Basic sanity check
272 (generic-mode-sanity-check name
273 comment-list keyword-list font-lock-list
274 auto-mode-list function-list description
)
276 ;; Remove any old entry
277 (setq generic-mode-alist
278 (delq (assq name generic-mode-alist
)
282 (setq generic-mode-alist
286 name comment-list keyword-list font-lock-list
287 auto-mode-list function-list
291 ;; Add it to auto-mode-alist
292 (generic-add-to-auto-mode name auto-mode-list t
)
294 ;; Define a function for it
295 (generic-create-generic-function name description
)
298 (defun generic-add-to-auto-mode (mode auto-mode-list
299 &optional remove-old prepend
)
300 "Add the entries for mode to `auto-mode-alist'.
301 If remove-old is non-nil, removes old entries first. If prepend is
302 non-nil, prepends entries to auto-mode-alist; otherwise, appends them."
304 (if (not (listp auto-mode-list
))
305 (error "%s is not a list" (princ auto-mode-list
)))
307 (let ((new-mode (intern (symbol-name mode
))))
309 (let ((auto-mode-entry))
310 (while (setq auto-mode-entry
(rassq new-mode auto-mode-alist
))
311 (setq auto-mode-alist
312 (delq auto-mode-entry
315 (mapcar '(lambda (entry)
316 (generic-add-auto-mode-entry new-mode entry prepend
))
319 (defun generic-add-auto-mode-entry (name entry
&optional prepend
)
320 "Add a new entry to the end of auto-mode-alist.
321 If prepend is non-nil, add the entry to the front of the list."
322 (let ((new-entry (list (cons entry name
))))
323 (setq auto-mode-alist
325 (append new-entry auto-mode-alist
)
326 (append auto-mode-alist new-entry
)))))
328 (defun generic-create-generic-function (name &optional description
)
329 "Create a generic mode function with NAME.
330 If DESCRIPTION is provided, it is used as the docstring."
331 (let ((symname (symbol-name name
)))
332 (fset (intern symname
)
335 (concat "Generic mode for type " symname
))
337 (list 'generic-mode-with-type
(list 'quote name
))))))
339 (defun generic-mode-with-type (&optional mode
)
340 "Go into the generic-mode MODE."
341 (let* ((type (or mode generic-mode-name
))
342 (generic-mode-list (assoc type generic-mode-alist
))
345 (if (not generic-mode-list
)
346 (error "Can't find generic-mode information for type %s"
347 (princ generic-mode-name
)))
349 ;; Put this after the point where we read generic-mode-name!
350 (kill-all-local-variables)
353 generic-mode-name type
354 generic-comment-list
(nth 1 generic-mode-list
)
355 generic-keywords-list
(nth 2 generic-mode-list
)
356 generic-font-lock-expressions
(nth 3 generic-mode-list
)
357 generic-mode-function-list
(nth 5 generic-mode-list
)
358 major-mode
'generic-mode
359 mode-name
(symbol-name type
)
362 (generic-mode-set-comments generic-comment-list
)
364 ;; Font-lock functionality
365 ;; Font-lock-defaults are always set even if there are no keywords
366 ;; or font-lock expressions, so comments can be highlighted.
367 (setq generic-font-lock-defaults nil
)
368 (generic-mode-set-font-lock generic-keywords-list
369 generic-font-lock-expressions
)
370 (make-local-variable 'font-lock-defaults
)
371 (setq font-lock-defaults
(list 'generic-font-lock-defaults nil
))
373 ;; Call a list of functions
374 (if generic-mode-function-list
375 (mapcar 'funcall generic-mode-function-list
))
380 (defun generic-mode (type)
381 "A mode to do basic comment and font-lock functionality
382 for files which are too small to warrant their own mode, but have
383 comment characters, keywords, and the like.
385 To define a generic-mode, use the function `define-generic-mode'.
386 To alter an existing generic-mode, use the `alter-generic-mode-'
387 convenience functions.
388 Some generic modes are defined in generic-extras.el"
390 (list (generic-read-type)))
391 (generic-mode-with-type (intern type
)))
393 ;;; Comment Functionality
394 (defun generic-mode-set-comments (comment-list)
395 "Set up comment functionality for generic mode."
396 (if (null comment-list
)
398 (let ((generic-mode-syntax-table (make-syntax-table)))
399 (make-local-variable 'comment-start
)
400 (make-local-variable 'comment-start-skip
)
401 (make-local-variable 'comment-end
)
402 (mapcar 'generic-mode-set-a-comment comment-list
)
403 (set-syntax-table generic-mode-syntax-table
))))
405 (defun generic-mode-set-a-comment (comment)
406 (and (char-or-string-p comment
)
407 (if (stringp comment
)
409 ((eq (length comment
) 1)
410 (generic-mode-set-comment-char
411 (string-to-char comment
)))
412 ((eq (length comment
) 2)
413 (generic-mode-set-comment-string comment
))
415 (error "Character string %s must be one or two characters long"
418 (generic-mode-set-comment-char comment
)))
420 (generic-mode-set-comment-pair comment
)))
422 (defun generic-mode-set-comment-char (comment-char)
423 "Set the given character as a comment character for generic mode."
424 (if (not comment-char
)
428 comment-start
(char-to-string comment-char
)
429 comment-start-skip
(concat comment-start
"+ *")
432 (modify-syntax-entry comment-char
"<"
433 generic-mode-syntax-table
)
434 (modify-syntax-entry ?
\n ">"
435 generic-mode-syntax-table
)))
437 (defun generic-mode-set-comment-string (comment-string)
438 "Set the given string as a comment string for generic mode."
439 (if (not comment-string
)
443 comment-start comment-string
444 comment-start-skip
(concat comment-start
" *")
447 (let ((first (elt comment-string
0))
448 (second (elt comment-string
1)))
449 ;; C++ style comments
450 (if (char-equal first second
)
452 (modify-syntax-entry first
"<12b"
453 generic-mode-syntax-table
)
454 (modify-syntax-entry ?
\n ">b"
455 generic-mode-syntax-table
)))
456 ;; Some other two character string
457 (modify-syntax-entry first
"<1"
458 generic-mode-syntax-table
)
459 (modify-syntax-entry second
"<2"
460 generic-mode-syntax-table
)
461 (modify-syntax-entry ?
\n ">"
462 generic-mode-syntax-table
))))
464 (defun generic-mode-set-comment-pair (comment-pair)
465 "Set the given comment pair as a comment start and end for generic mode."
466 (let ((generic-comment-start (car comment-pair
))
467 (generic-comment-end (cdr comment-pair
))
470 comment-end generic-comment-end
471 comment-start generic-comment-start
472 comment-start-skip
(concat generic-comment-start
" *")
476 (if (not (and (stringp generic-comment-start
)
477 (stringp generic-comment-end
)))
478 (error "Elements of cons pair must be strings"))
479 (if (not (and (equal (length generic-comment-start
) 2)
480 (equal (length generic-comment-end
) 2)))
481 (error "Start and end must be exactly two characters long"))
483 (let ((first (elt generic-comment-start
0))
484 (second (elt generic-comment-start
1))
485 (third (elt generic-comment-end
0))
486 (fourth (elt generic-comment-end
1))
489 (modify-syntax-entry first
". 1" generic-mode-syntax-table
)
490 (modify-syntax-entry second
". 2" generic-mode-syntax-table
)
497 ((char-equal first third
) " 13")
498 ((char-equal second third
) " 23")
501 generic-mode-syntax-table
)
508 ((char-equal first fourth
) " 14")
509 ((char-equal second fourth
) " 24")
512 generic-mode-syntax-table
)
515 (defun generic-mode-set-font-lock (keywords font-lock-expressions
)
516 "Set up font-lock functionality for generic mode."
517 (let ((generic-font-lock-expressions))
521 generic-font-lock-expressions
527 (mapconcat 'identity keywords
"\\>\\|\\<")
529 1 'font-lock-keyword-face
))
530 generic-font-lock-expressions
)))
531 ;; Other font-lock expressions
532 (if font-lock-expressions
533 (setq generic-font-lock-expressions
535 font-lock-expressions
536 generic-font-lock-expressions
)))
537 (if (not (or font-lock-expressions keywords
))
539 (setq generic-font-lock-defaults generic-font-lock-expressions
))
542 ;; Support for [KEYWORD] constructs found in INF, INI and Samba files
543 (defun generic-bracket-support ()
544 (setq imenu-generic-expression
545 '((nil "^\\[\\(.*\\)\\]" 1))))
547 ;; This generic mode is always defined
548 (define-generic-mode 'default-generic-mode
(list ?
#) nil nil nil nil
)
550 ;; A more general solution would allow us to enter generic-mode for
551 ;; *any* comment character, but would require us to synthesize a new
552 ;; generic-mode on the fly. I think this gives us most of what we
554 (defun generic-mode-find-file-hook ()
555 "Hook to enter default-generic-mode automatically
556 if the first few lines of a file in fundamental-mode start with a hash
557 comment character. This hook will be installed if the variable
558 `generic-use-find-file-hook' is non-nil. The variable `generic-lines-to-scan'
559 determines the number of lines to look at."
560 (if (not (eq major-mode
'fundamental-mode
))
562 (if (or (> 1 generic-lines-to-scan
)
563 (< 50 generic-lines-to-scan
))
564 (error "Variable `generic-lines-to-scan' should be set to a small"
566 (let ((comment-regexp "")
569 (while (< count generic-lines-to-scan
)
570 (setq comment-regexp
(concat comment-regexp
571 generic-find-file-regexp
))
572 (setq count
(1+ count
)))
574 (goto-char (point-min))
575 (if (looking-at comment-regexp
)
576 (generic-mode-with-type 'default-generic-mode
))))))
578 (defun generic-mode-ini-file-find-file-hook ()
579 "Hook to enter default-generic-mode automatically
580 if the first few lines of a file in fundamental-mode look like an INI file.
581 This hook is NOT installed by default."
582 (if (not (eq major-mode
'fundamental-mode
))
585 (goto-char (point-min))
586 (if (looking-at "^\\s-*\\[.*\\]")
587 (generic-mode-with-type 'ini-generic-mode
)))))
589 (and generic-use-find-file-hook
590 (add-hook 'find-file-hooks
'generic-mode-find-file-hook
))
592 (defun generic-make-keywords-list (keywords-list face
&optional prefix suffix
)
593 "Return a regular expression matching the specified keywords.
594 The regexp is highlighted with FACE."
596 ;; Don't check here; face may not be defined yet
597 ;; (if (not (facep face))
598 ;; (error "Face %s is not defined" (princ face)))
599 (if (not (listp keywords-list
))
600 (error "Keywords argument must be a list of strings"))
605 (mapconcat 'identity keywords-list
"\\>\\|\\<")
610 (provide 'generic-mode
)
612 ;;; generic-mode.el ends here