1;;; easy-mmode.el --- easy definition for major and minor modes
2
3;; Copyright (C) 1997, 2000, 2001, 2002, 2003, 2004, 2005,
4;;   2006, 2007 Free Software Foundation, Inc.
5
6;; Author: Georges Brun-Cottan <Georges.Brun-Cottan@inria.fr>
7;; Maintainer: Stefan Monnier <monnier@gnu.org>
8
9;; Keywords: extensions lisp
10
11;; This file is part of GNU Emacs.
12
13;; GNU Emacs is free software; you can redistribute it and/or modify
14;; it under the terms of the GNU General Public License as published by
15;; the Free Software Foundation; either version 2, or (at your option)
16;; any later version.
17
18;; GNU Emacs is distributed in the hope that it will be useful,
19;; but WITHOUT ANY WARRANTY; without even the implied warranty of
20;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21;; GNU General Public License for more details.
22
23;; You should have received a copy of the GNU General Public License
24;; along with GNU Emacs; see the file COPYING.  If not, write to the
25;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
26;; Boston, MA 02110-1301, USA.
27
28;;; Commentary:
29
30;; Minor modes are useful and common.  This package makes defining a
31;; minor mode easy, by focusing on the writing of the minor mode
32;; functionalities themselves.  Moreover, this package enforces a
33;; conventional naming of user interface primitives, making things
34;; natural for the minor-mode end-users.
35
36;; For each mode, easy-mmode defines the following:
37;; <mode>      : The minor mode predicate. A buffer-local variable.
38;; <mode>-map  : The keymap possibly associated to <mode>.
39;;       see `define-minor-mode' documentation
40;;
41;; eval
42;;  (pp (macroexpand '(define-minor-mode <your-mode> <doc>)))
43;; to check the result before using it.
44
45;; The order in which minor modes are installed is important.  Keymap
46;; lookup proceeds down minor-mode-map-alist, and the order there
47;; tends to be the reverse of the order in which the modes were
48;; installed.  Perhaps there should be a feature to let you specify
49;; orderings.
50
51;; Additionally to `define-minor-mode', the package provides convenient
52;; ways to define keymaps, and other helper functions for major and minor modes.
53
54;;; Code:
55
56(eval-when-compile (require 'cl))
57
58(defun easy-mmode-pretty-mode-name (mode &optional lighter)
59  "Turn the symbol MODE into a string intended for the user.
60If provided, LIGHTER will be used to help choose capitalization by,
61replacing its case-insensitive matches with the literal string in LIGHTER."
62  (let* ((case-fold-search t)
63	 ;; Produce "Foo-Bar minor mode" from foo-bar-minor-mode.
64	 (name (concat (replace-regexp-in-string
65			;; If the original mode name included "-minor" (some
66			;; of them don't, e.g. auto-revert-mode), then
67			;; replace it with " minor".
68			"-Minor" " minor"
69			;; "foo-bar-minor" -> "Foo-Bar-Minor"
70			(capitalize (replace-regexp-in-string
71				     ;; "foo-bar-minor-mode" -> "foo-bar-minor"
72				     "-mode\\'" "" (symbol-name mode))))
73		       " mode")))
74    (if (not (stringp lighter)) name
75      ;; Strip leading and trailing whitespace from LIGHTER.
76      (setq lighter (replace-regexp-in-string "\\`\\s-+\\|\\s-+\\'" ""
77					      lighter))
78      ;; Replace any (case-insensitive) matches for LIGHTER in NAME
79      ;; with a literal LIGHTER.  E.g., if NAME is "Iimage mode" and
80      ;; LIGHTER is " iImag", then this will produce "iImage mode".
81      ;; (LIGHTER normally comes from the mode-line string passed to
82      ;; define-minor-mode, and normally includes at least one leading
83      ;; space.)
84      (replace-regexp-in-string (regexp-quote lighter) lighter name t t))))
85
86;;;###autoload
87(defalias 'easy-mmode-define-minor-mode 'define-minor-mode)
88;;;###autoload
89(defmacro define-minor-mode (mode doc &optional init-value lighter keymap &rest body)
90  "Define a new minor mode MODE.
91This function defines the associated control variable MODE, keymap MODE-map,
92and toggle command MODE.
93
94DOC is the documentation for the mode toggle command.
95Optional INIT-VALUE is the initial value of the mode's variable.
96Optional LIGHTER is displayed in the modeline when the mode is on.
97Optional KEYMAP is the default (defvar) keymap bound to the mode keymap.
98  If it is a list, it is passed to `easy-mmode-define-keymap'
99  in order to build a valid keymap.  It's generally better to use
100  a separate MODE-map variable than to use this argument.
101The above three arguments can be skipped if keyword arguments are
102used (see below).
103
104BODY contains code to execute each time the mode is activated or deactivated.
105  It is executed after toggling the mode,
106  and before running the hook variable `mode-HOOK'.
107  Before the actual body code, you can write keyword arguments (alternating
108  keywords and values).  These following keyword arguments are supported (other
109  keywords will be passed to `defcustom' if the minor mode is global):
110:group GROUP	Custom group name to use in all generated `defcustom' forms.
111		Defaults to MODE without the possible trailing \"-mode\".
112		Don't use this default group name unless you have written a
113		`defgroup' to define that group properly.
114:global GLOBAL	If non-nil specifies that the minor mode is not meant to be
115		buffer-local, so don't make the variable MODE buffer-local.
116		By default, the mode is buffer-local.
117:init-value VAL	Same as the INIT-VALUE argument.
118:lighter SPEC	Same as the LIGHTER argument.
119:keymap MAP	Same as the KEYMAP argument.
120:require SYM	Same as in `defcustom'.
121
122For example, you could write
123  (define-minor-mode foo-mode \"If enabled, foo on you!\"
124    :lighter \" Foo\" :require 'foo :global t :group 'hassle :version \"27.5\"
125    ...BODY CODE...)"
126  (declare (debug (&define name stringp
127			   [&optional [¬ keywordp] sexp
128			    &optional [¬ keywordp] sexp
129			    &optional [¬ keywordp] sexp]
130			   [&rest [keywordp sexp]]
131			   def-body)))
132
133  ;; Allow skipping the first three args.
134  (cond
135   ((keywordp init-value)
136    (setq body (list* init-value lighter keymap body)
137	  init-value nil lighter nil keymap nil))
138   ((keywordp lighter)
139    (setq body (list* lighter keymap body) lighter nil keymap nil))
140   ((keywordp keymap) (push keymap body) (setq keymap nil)))
141
142  (let* ((last-message (current-message))
143	 (mode-name (symbol-name mode))
144	 (pretty-name (easy-mmode-pretty-mode-name mode lighter))
145	 (globalp nil)
146	 (set nil)
147	 (initialize nil)
148	 (group nil)
149	 (type nil)
150	 (extra-args nil)
151	 (extra-keywords nil)
152	 (require t)
153	 (hook (intern (concat mode-name "-hook")))
154	 (hook-on (intern (concat mode-name "-on-hook")))
155	 (hook-off (intern (concat mode-name "-off-hook")))
156	 keyw keymap-sym)
157
158    ;; Check keys.
159    (while (keywordp (setq keyw (car body)))
160      (setq body (cdr body))
161      (case keyw
162	(:init-value (setq init-value (pop body)))
163	(:lighter (setq lighter (pop body)))
164	(:global (setq globalp (pop body)))
165	(:extra-args (setq extra-args (pop body)))
166	(:set (setq set (list :set (pop body))))
167	(:initialize (setq initialize (list :initialize (pop body))))
168	(:group (setq group (nconc group (list :group (pop body)))))
169	(:type (setq type (list :type (pop body))))
170	(:require (setq require (pop body)))
171	(:keymap (setq keymap (pop body)))
172	(t (push keyw extra-keywords) (push (pop body) extra-keywords))))
173
174    (setq keymap-sym (if (and keymap (symbolp keymap)) keymap
175		       (intern (concat mode-name "-map"))))
176
177    (unless set (setq set '(:set 'custom-set-minor-mode)))
178
179    (unless initialize
180      (setq initialize '(:initialize 'custom-initialize-default)))
181
182    (unless group
183      ;; We might as well provide a best-guess default group.
184      (setq group
185	    `(:group ',(intern (replace-regexp-in-string
186				"-mode\\'" "" mode-name)))))
187
188    (unless type (setq type '(:type 'boolean)))
189
190    `(progn
191       ;; Define the variable to enable or disable the mode.
192       ,(if (not globalp)
193	    `(progn
194	       (defvar ,mode ,init-value ,(format "Non-nil if %s is enabled.
195Use the command `%s' to change this variable." pretty-name mode))
196	       (make-variable-buffer-local ',mode))
197
198	  (let ((base-doc-string
199                 (concat "Non-nil if %s is enabled.
200See the command `%s' for a description of this minor mode."
201                         (if body "
202Setting this variable directly does not take effect;
203either customize it (see the info node `Easy Customization')
204or call the function `%s'."))))
205	    `(defcustom ,mode ,init-value
206	       ,(format base-doc-string pretty-name mode mode)
207	       ,@set
208	       ,@initialize
209	       ,@group
210	       ,@type
211	       ,@(unless (eq require t) `(:require ,require))
212               ,@(nreverse extra-keywords))))
213
214       ;; The actual function.
215       (defun ,mode (&optional arg ,@extra-args)
216	 ,(or doc
217	      (format (concat "Toggle %s on or off.
218Interactively, with no prefix argument, toggle the mode.
219With universal prefix ARG turn mode on.
220With zero or negative ARG turn mode off.
221\\{%s}") pretty-name keymap-sym))
222	 ;; Use `toggle' rather than (if ,mode 0 1) so that using
223	 ;; repeat-command still does the toggling correctly.
224	 (interactive (list (or current-prefix-arg 'toggle)))
225	 (setq ,mode
226	       (cond
227		((eq arg 'toggle) (not ,mode))
228		(arg (> (prefix-numeric-value arg) 0))
229		(t
230		 (if (null ,mode) t
231		   (message
232		    "Toggling %s off; better pass an explicit argument."
233		    ',mode)
234		   nil))))
235	 ,@body
236	 ;; The on/off hooks are here for backward compatibility only.
237	 (run-hooks ',hook (if ,mode ',hook-on ',hook-off))
238	 (if (called-interactively-p)
239	     (progn
240	       ,(if globalp `(customize-mark-as-set ',mode))
241	       ;; Avoid overwriting a message shown by the body,
242               ;; but do overwrite previous messages.
243	       (unless  ,(and (current-message)
244                              (not (equal last-message (current-message))))
245		 (message ,(format "%s %%sabled" pretty-name)
246			  (if ,mode "en" "dis")))))
247	 (force-mode-line-update)
248	 ;; Return the new setting.
249	 ,mode)
250
251       ;; Autoloading a define-minor-mode autoloads everything
252       ;; up-to-here.
253       :autoload-end
254
255       ;; Define the minor-mode keymap.
256       ,(unless (symbolp keymap)	;nil is also a symbol.
257	  `(defvar ,keymap-sym
258	     (let ((m ,keymap))
259	       (cond ((keymapp m) m)
260		     ((listp m) (easy-mmode-define-keymap m))
261		     (t (error "Invalid keymap %S" ,keymap))))
262	     ,(format "Keymap for `%s'." mode-name)))
263
264       (add-minor-mode ',mode ',lighter
265		       ,(if keymap keymap-sym
266			  `(if (boundp ',keymap-sym)
267			       (symbol-value ',keymap-sym)))))))
268
269;;;
270;;; make global minor mode
271;;;
272
273;;;###autoload
274(defalias 'easy-mmode-define-global-mode 'define-globalized-minor-mode)
275;;;###autoload
276(defalias 'define-global-minor-mode 'define-globalized-minor-mode)
277;;;###autoload
278(defmacro define-globalized-minor-mode (global-mode mode turn-on &rest keys)
279  "Make a global mode GLOBAL-MODE corresponding to buffer-local minor MODE.
280TURN-ON is a function that will be called with no args in every buffer
281  and that should try to turn MODE on if applicable for that buffer.
282KEYS is a list of CL-style keyword arguments.  As the minor mode
283  defined by this function is always global, any :global keyword is
284  ignored.  Other keywords have the same meaning as in `define-minor-mode',
285  which see.  In particular, :group specifies the custom group.
286  The most useful keywords are those that are passed on to the
287  `defcustom'.  It normally makes no sense to pass the :lighter
288  or :keymap keywords to `define-globalized-minor-mode', since these
289  are usually passed to the buffer-local version of the minor mode.
290
291If MODE's set-up depends on the major mode in effect when it was
292enabled, then disabling and reenabling MODE should make MODE work
293correctly with the current major mode.  This is important to
294prevent problems with derived modes, that is, major modes that
295call another major mode in their body."
296
297  (let* ((global-mode-name (symbol-name global-mode))
298	 (pretty-name (easy-mmode-pretty-mode-name mode))
299	 (pretty-global-name (easy-mmode-pretty-mode-name global-mode))
300	 (group nil)
301	 (extra-keywords nil)
302	 (MODE-buffers (intern (concat global-mode-name "-buffers")))
303	 (MODE-enable-in-buffers
304	  (intern (concat global-mode-name "-enable-in-buffers")))
305	 (MODE-check-buffers
306	  (intern (concat global-mode-name "-check-buffers")))
307	 (MODE-cmhh (intern (concat global-mode-name "-cmhh")))
308	 (MODE-major-mode (intern (concat (symbol-name mode) "-major-mode")))
309	 keyw)
310
311    ;; Check keys.
312    (while (keywordp (setq keyw (car keys)))
313      (setq keys (cdr keys))
314      (case keyw
315	(:group (setq group (nconc group (list :group (pop keys)))))
316	(:global (setq keys (cdr keys)))
317	(t (push keyw extra-keywords) (push (pop keys) extra-keywords))))
318
319    (unless group
320      ;; We might as well provide a best-guess default group.
321      (setq group
322	    `(:group ',(intern (replace-regexp-in-string
323				"-mode\\'" "" (symbol-name mode))))))
324
325    `(progn
326       (defvar ,MODE-major-mode nil)
327       (make-variable-buffer-local ',MODE-major-mode)
328       ;; The actual global minor-mode
329       (define-minor-mode ,global-mode
330	 ,(format "Toggle %s in every possible buffer.
331With prefix ARG, turn %s on if and only if ARG is positive.
332%s is enabled in all buffers where `%s' would do it.
333See `%s' for more information on %s."
334		  pretty-name pretty-global-name pretty-name turn-on
335		  mode pretty-name)
336	 :global t ,@group ,@(nreverse extra-keywords)
337
338	 ;; Setup hook to handle future mode changes and new buffers.
339	 (if ,global-mode
340	     (progn
341	       (add-hook 'after-change-major-mode-hook
342			 ',MODE-enable-in-buffers)
343	       (add-hook 'find-file-hook ',MODE-check-buffers)
344	       (add-hook 'change-major-mode-hook ',MODE-cmhh))
345	   (remove-hook 'after-change-major-mode-hook ',MODE-enable-in-buffers)
346	   (remove-hook 'find-file-hook ',MODE-check-buffers)
347	   (remove-hook 'change-major-mode-hook ',MODE-cmhh))
348
349	 ;; Go through existing buffers.
350	 (dolist (buf (buffer-list))
351	   (with-current-buffer buf
352	     (if ,global-mode (,turn-on) (when ,mode (,mode -1))))))
353
354       ;; Autoloading define-globalized-minor-mode autoloads everything
355       ;; up-to-here.
356       :autoload-end
357
358       ;; List of buffers left to process.
359       (defvar ,MODE-buffers nil)
360
361       ;; The function that calls TURN-ON in each buffer.
362       (defun ,MODE-enable-in-buffers ()
363	 (dolist (buf ,MODE-buffers)
364	   (when (buffer-live-p buf)
365	     (with-current-buffer buf
366	       (if ,mode
367		   (unless (eq ,MODE-major-mode major-mode)
368		     (,mode -1)
369		     (,turn-on)
370		     (setq ,MODE-major-mode major-mode))
371		 (,turn-on)
372		 (setq ,MODE-major-mode major-mode))))))
373       (put ',MODE-enable-in-buffers 'definition-name ',global-mode)
374
375       (defun ,MODE-check-buffers ()
376	 (,MODE-enable-in-buffers)
377	 (setq ,MODE-buffers nil)
378	 (remove-hook 'post-command-hook ',MODE-check-buffers))
379       (put ',MODE-check-buffers 'definition-name ',global-mode)
380
381       ;; The function that catches kill-all-local-variables.
382       (defun ,MODE-cmhh ()
383	 (add-to-list ',MODE-buffers (current-buffer))
384	 (add-hook 'post-command-hook ',MODE-check-buffers))
385       (put ',MODE-cmhh 'definition-name ',global-mode))))
386
387;;;
388;;; easy-mmode-defmap
389;;;
390
391(if (fboundp 'set-keymap-parents)
392    (defalias 'easy-mmode-set-keymap-parents 'set-keymap-parents)
393  (defun easy-mmode-set-keymap-parents (m parents)
394    (set-keymap-parent
395     m
396     (cond
397      ((not (consp parents)) parents)
398      ((not (cdr parents)) (car parents))
399      (t (let ((m (copy-keymap (pop parents))))
400	   (easy-mmode-set-keymap-parents m parents)
401	   m))))))
402
403;;;###autoload
404(defun easy-mmode-define-keymap (bs &optional name m args)
405  "Return a keymap built from bindings BS.
406BS must be a list of (KEY . BINDING) where
407KEY and BINDINGS are suitable for `define-key'.
408Optional NAME is passed to `make-sparse-keymap'.
409Optional map M can be used to modify an existing map.
410ARGS is a list of additional keyword arguments."
411  (let (inherit dense)
412    (while args
413      (let ((key (pop args))
414	    (val (pop args)))
415	(case key
416	 (:name (setq name val))
417	 (:dense (setq dense val))
418	 (:inherit (setq inherit val))
419	 (:group)
420	 (t (message "Unknown argument %s in defmap" key)))))
421    (unless (keymapp m)
422      (setq bs (append m bs))
423      (setq m (if dense (make-keymap name) (make-sparse-keymap name))))
424    (dolist (b bs)
425      (let ((keys (car b))
426	    (binding (cdr b)))
427	(dolist (key (if (consp keys) keys (list keys)))
428	  (cond
429	   ((symbolp key)
430	    (substitute-key-definition key binding m global-map))
431	   ((null binding)
432	    (unless (keymapp (lookup-key m key)) (define-key m key binding)))
433	   ((let ((o (lookup-key m key)))
434	      (or (null o) (numberp o) (eq o 'undefined)))
435	    (define-key m key binding))))))
436    (cond
437     ((keymapp inherit) (set-keymap-parent m inherit))
438     ((consp inherit) (easy-mmode-set-keymap-parents m inherit)))
439    m))
440
441;;;###autoload
442(defmacro easy-mmode-defmap (m bs doc &rest args)
443  `(defconst ,m
444     (easy-mmode-define-keymap ,bs nil (if (boundp ',m) ,m) ,(cons 'list args))
445     ,doc))
446
447
448;;;
449;;; easy-mmode-defsyntax
450;;;
451
452(defun easy-mmode-define-syntax (css args)
453  (let ((st (make-syntax-table (plist-get args :copy)))
454	(parent (plist-get args :inherit)))
455    (dolist (cs css)
456      (let ((char (car cs))
457	    (syntax (cdr cs)))
458	(if (sequencep char)
459	    (mapcar (lambda (c) (modify-syntax-entry c syntax st)) char)
460	  (modify-syntax-entry char syntax st))))
461    (if parent (set-char-table-parent
462		st (if (symbolp parent) (symbol-value parent) parent)))
463    st))
464
465;;;###autoload
466(defmacro easy-mmode-defsyntax (st css doc &rest args)
467  "Define variable ST as a syntax-table.
468CSS contains a list of syntax specifications of the form (CHAR . SYNTAX)."
469  `(progn
470     (autoload 'easy-mmode-define-syntax "easy-mmode")
471     (defconst ,st (easy-mmode-define-syntax ,css ,(cons 'list args)) ,doc)))
472
473
474
475;;;
476;;; easy-mmode-define-navigation
477;;;
478
479(defmacro easy-mmode-define-navigation (base re &optional name endfun narrowfun)
480  "Define BASE-next and BASE-prev to navigate in the buffer.
481RE determines the places the commands should move point to.
482NAME should describe the entities matched by RE.  It is used to build
483  the docstrings of the two functions.
484BASE-next also tries to make sure that the whole entry is visible by
485  searching for its end (by calling ENDFUN if provided or by looking for
486  the next entry) and recentering if necessary.
487ENDFUN should return the end position (with or without moving point).
488NARROWFUN non-nil means to check for narrowing before moving, and if
489found, do widen first and then call NARROWFUN with no args after moving."
490  (let* ((base-name (symbol-name base))
491	 (prev-sym (intern (concat base-name "-prev")))
492	 (next-sym (intern (concat base-name "-next")))
493         (check-narrow-maybe
494	  (when narrowfun
495	    '(setq was-narrowed
496		   (prog1 (or (< (- (point-max) (point-min)) (buffer-size)))
497		     (widen)))))
498         (re-narrow-maybe (when narrowfun
499                            `(when was-narrowed (,narrowfun)))))
500    (unless name (setq name base-name))
501    `(progn
502       (add-to-list 'debug-ignored-errors
503		    ,(concat "^No \\(previous\\|next\\) " (regexp-quote name)))
504       (defun ,next-sym (&optional count)
505	 ,(format "Go to the next COUNT'th %s." name)
506	 (interactive "p")
507	 (unless count (setq count 1))
508	 (if (< count 0) (,prev-sym (- count))
509	   (if (looking-at ,re) (setq count (1+ count)))
510           (let (was-narrowed)
511             ,check-narrow-maybe
512             (if (not (re-search-forward ,re nil t count))
513                 (if (looking-at ,re)
514                     (goto-char (or ,(if endfun `(,endfun)) (point-max)))
515                   (error "No next %s" ,name))
516               (goto-char (match-beginning 0))
517               (when (and (eq (current-buffer) (window-buffer (selected-window)))
518                          (interactive-p))
519                 (let ((endpt (or (save-excursion
520                                    ,(if endfun `(,endfun)
521                                       `(re-search-forward ,re nil t 2)))
522                                  (point-max))))
523                   (unless (pos-visible-in-window-p endpt nil t)
524                     (recenter '(0))))))
525             ,re-narrow-maybe)))
526       (put ',next-sym 'definition-name ',base)
527       (defun ,prev-sym (&optional count)
528	 ,(format "Go to the previous COUNT'th %s" (or name base-name))
529	 (interactive "p")
530	 (unless count (setq count 1))
531	 (if (< count 0) (,next-sym (- count))
532           (let (was-narrowed)
533             ,check-narrow-maybe
534             (unless (re-search-backward ,re nil t count)
535               (error "No previous %s" ,name))
536             ,re-narrow-maybe)))
537       (put ',prev-sym 'definition-name ',base))))
538
539
540(provide 'easy-mmode)
541
542;;; arch-tag: d48a5250-6961-4528-9cb0-3c9ea042a66a
543;;; easy-mmode.el ends here
544