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
))
329 (generic-mode-hooks (intern (concat (symbol-name type
) "-hooks")))
332 (and (not generic-mode-list
)
333 (error "Can't find generic-mode information for type %s"
334 (princ generic-mode-name
)))
336 ;; Put this after the point where we read generic-mode-name!
337 (kill-all-local-variables)
340 generic-mode-name type
341 generic-comment-list
(nth 1 generic-mode-list
)
342 generic-keywords-list
(nth 2 generic-mode-list
)
343 generic-font-lock-expressions
(nth 3 generic-mode-list
)
344 generic-mode-function-list
(nth 5 generic-mode-list
)
346 mode-name
(symbol-name type
)
349 (generic-mode-set-comments generic-comment-list
)
351 ;; Font-lock functionality
352 ;; Font-lock-defaults are always set even if there are no keywords
353 ;; or font-lock expressions, so comments can be highlighted.
354 (setq generic-font-lock-defaults nil
)
355 (generic-mode-set-font-lock generic-keywords-list
356 generic-font-lock-expressions
)
357 (make-local-variable 'font-lock-defaults
)
358 (setq font-lock-defaults
(list 'generic-font-lock-defaults nil
))
360 ;; Call a list of functions
361 (and generic-mode-function-list
362 (mapcar 'funcall generic-mode-function-list
))
364 (run-hooks generic-mode-hooks
)
369 (defun generic-mode (type)
370 "A mode to do basic comment and font-lock functionality
371 for files which are too small to warrant their own mode, but have
372 comment characters, keywords, and the like.
374 To define a generic-mode, use the function `define-generic-mode'.
375 Some generic modes are defined in `generic-x.el'."
377 (list (generic-read-type)))
378 (generic-mode-with-type (intern type
)))
380 ;;; Comment Functionality
381 (defun generic-mode-set-comments (comment-list)
382 "Set up comment functionality for generic mode."
383 (if (null comment-list
)
385 (let ((generic-mode-syntax-table (make-syntax-table)))
386 (make-local-variable 'comment-start
)
387 (make-local-variable 'comment-start-skip
)
388 (make-local-variable 'comment-end
)
389 (mapcar 'generic-mode-set-a-comment comment-list
)
390 (set-syntax-table generic-mode-syntax-table
))))
392 (defun generic-mode-set-a-comment (comment)
393 (and (char-or-string-p comment
)
394 (if (stringp comment
)
396 ((eq (length comment
) 1)
397 (generic-mode-set-comment-char
398 (string-to-char comment
)))
399 ((eq (length comment
) 2)
400 (generic-mode-set-comment-string comment
))
402 (error "Character string %s must be one or two characters long"
405 (generic-mode-set-comment-char comment
)))
407 (generic-mode-set-comment-pair comment
)))
409 (defun generic-mode-set-comment-char (comment-char)
410 "Set the given character as a comment character for generic mode."
411 (if (not comment-char
)
415 comment-start
(char-to-string comment-char
)
416 comment-start-skip
(concat comment-start
"+ *")
419 (modify-syntax-entry comment-char
"<"
420 generic-mode-syntax-table
)
421 (modify-syntax-entry ?
\n ">"
422 generic-mode-syntax-table
)))
424 (defun generic-mode-set-comment-string (comment-string)
425 "Set the given string as a comment string for generic mode."
426 (if (not comment-string
)
430 comment-start comment-string
431 comment-start-skip
(concat comment-start
" *")
434 (let ((first (elt comment-string
0))
435 (second (elt comment-string
1)))
436 ;; C++ style comments
437 (if (char-equal first second
)
439 (modify-syntax-entry first
"<12b"
440 generic-mode-syntax-table
)
441 (modify-syntax-entry ?
\n ">b"
442 generic-mode-syntax-table
)))
443 ;; Some other two character string
444 (modify-syntax-entry first
"<1"
445 generic-mode-syntax-table
)
446 (modify-syntax-entry second
"<2"
447 generic-mode-syntax-table
)
448 (modify-syntax-entry ?
\n ">"
449 generic-mode-syntax-table
))))
451 (defun generic-mode-set-comment-pair (comment-pair)
452 "Set the given comment pair as a comment start and end for generic mode."
453 (let ((generic-comment-start (car comment-pair
))
454 (generic-comment-end (cdr comment-pair
))
457 comment-end generic-comment-end
458 comment-start generic-comment-start
459 comment-start-skip
(concat generic-comment-start
" *")
463 (and (not (and (stringp generic-comment-start
)
464 (stringp generic-comment-end
)))
465 (error "Elements of cons pair must be strings"))
466 (and (not (and (equal (length generic-comment-start
) 2)
467 (equal (length generic-comment-end
) 2)))
468 (error "Start and end must be exactly two characters long"))
470 (let ((first (elt generic-comment-start
0))
471 (second (elt generic-comment-start
1))
472 (third (elt generic-comment-end
0))
473 (fourth (elt generic-comment-end
1))
476 (modify-syntax-entry first
". 1" generic-mode-syntax-table
)
477 (modify-syntax-entry second
". 2" generic-mode-syntax-table
)
484 ((char-equal first third
) " 13")
485 ((char-equal second third
) " 23")
488 generic-mode-syntax-table
)
495 ((char-equal first fourth
) " 14")
496 ((char-equal second fourth
) " 24")
499 generic-mode-syntax-table
)
502 (defun generic-mode-set-font-lock (keywords font-lock-expressions
)
503 "Set up font-lock functionality for generic mode."
504 (let ((generic-font-lock-expressions))
508 generic-font-lock-expressions
510 (list (let ((regexp (regexp-opt keywords
)))
511 (list (concat "\\<\\(" regexp
"\\)\\>")
513 'font-lock-keyword-face
)))
514 generic-font-lock-expressions
)))
515 ;; Other font-lock expressions
516 (and font-lock-expressions
517 (setq generic-font-lock-expressions
519 font-lock-expressions
520 generic-font-lock-expressions
)))
521 (and (or font-lock-expressions keywords
)
522 (setq generic-font-lock-defaults generic-font-lock-expressions
))
525 ;; Support for [KEYWORD] constructs found in INF, INI and Samba files
526 (defun generic-bracket-support ()
527 (setq imenu-generic-expression
528 '((nil "^\\[\\(.*\\)\\]" 1))
529 imenu-case-fold-search t
))
531 ;; This generic mode is always defined
532 (define-generic-mode 'default-generic-mode
(list ?
#) nil nil nil nil
)
534 ;; A more general solution would allow us to enter generic-mode for
535 ;; *any* comment character, but would require us to synthesize a new
536 ;; generic-mode on the fly. I think this gives us most of what we
538 (defun generic-mode-find-file-hook ()
539 "Hook to enter default-generic-mode automatically
540 if the first few lines of a file in fundamental-mode start with a hash
541 comment character. This hook will be installed if the variable
542 `generic-use-find-file-hook' is non-nil. The variable `generic-lines-to-scan'
543 determines the number of lines to look at."
544 (if (not (eq major-mode
'fundamental-mode
))
546 (and (or (> 1 generic-lines-to-scan
)
547 (< 50 generic-lines-to-scan
))
548 (error "Variable `generic-lines-to-scan' should be set to a small"
550 (let ((comment-regexp "")
553 (while (< count generic-lines-to-scan
)
554 (setq comment-regexp
(concat comment-regexp
555 generic-find-file-regexp
))
556 (setq count
(1+ count
)))
558 (goto-char (point-min))
559 (and (looking-at comment-regexp
)
560 (generic-mode-with-type 'default-generic-mode
))))))
562 (defun generic-mode-ini-file-find-file-hook ()
563 "Hook to enter default-generic-mode automatically
564 if the first few lines of a file in fundamental-mode look like an INI file.
565 This hook is NOT installed by default."
566 (and (eq major-mode
'fundamental-mode
)
568 (goto-char (point-min))
569 (and (looking-at "^\\s-*\\[.*\\]")
570 (generic-mode-with-type 'ini-generic-mode
)))))
572 (and generic-use-find-file-hook
573 (add-hook 'find-file-hooks
'generic-mode-find-file-hook
))
575 (defun generic-make-keywords-list (keywords-list face
&optional prefix suffix
)
576 "Return a regular expression matching the specified keywords.
577 The regexp is highlighted with FACE."
578 (and (not (listp keywords-list
))
579 (error "Keywords argument must be a list of strings"))
580 (list (concat (or prefix
"")
582 ;; Use an optimized regexp.
583 (regexp-opt keywords-list t
)
591 ;;; generic.el ends here