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5e046f6d | 1 | ;;; derived.el --- allow inheritance of major modes |
84ae4908 | 2 | ;; (formerly mode-clone.el) |
5e046f6d | 3 | |
ba318903 | 4 | ;; Copyright (C) 1993-1994, 1999, 2001-2014 Free Software Foundation, |
ab422c4d | 5 | ;; Inc. |
5e046f6d JB |
6 | |
7 | ;; Author: David Megginson (dmeggins@aix1.uottawa.ca) | |
34dc21db | 8 | ;; Maintainer: emacs-devel@gnu.org |
5e046f6d | 9 | ;; Keywords: extensions |
bd78fa1d | 10 | ;; Package: emacs |
5e046f6d JB |
11 | |
12 | ;; This file is part of GNU Emacs. | |
13 | ||
d6cba7ae | 14 | ;; GNU Emacs is free software: you can redistribute it and/or modify |
5e046f6d | 15 | ;; it under the terms of the GNU General Public License as published by |
d6cba7ae GM |
16 | ;; the Free Software Foundation, either version 3 of the License, or |
17 | ;; (at your option) any later version. | |
5e046f6d JB |
18 | |
19 | ;; GNU Emacs is distributed in the hope that it will be useful, | |
20 | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of | |
21 | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
22 | ;; GNU General Public License for more details. | |
23 | ||
24 | ;; You should have received a copy of the GNU General Public License | |
d6cba7ae | 25 | ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. |
5e046f6d JB |
26 | \f |
27 | ;;; Commentary: | |
28 | ||
29 | ;; GNU Emacs is already, in a sense, object oriented -- each object | |
30 | ;; (buffer) belongs to a class (major mode), and that class defines | |
31 | ;; the relationship between messages (input events) and methods | |
32 | ;; (commands) by means of a keymap. | |
33 | ;; | |
34 | ;; The only thing missing is a good scheme of inheritance. It is | |
35 | ;; possible to simulate a single level of inheritance with generous | |
36 | ;; use of hooks and a bit of work -- sgml-mode, for example, also runs | |
37 | ;; the hooks for text-mode, and keymaps can inherit from other keymaps | |
38 | ;; -- but generally, each major mode ends up reinventing the wheel. | |
39 | ;; Ideally, someone should redesign all of Emacs's major modes to | |
40 | ;; follow a more conventional object-oriented system: when defining a | |
41 | ;; new major mode, the user should need only to name the existing mode | |
42 | ;; it is most similar to, then list the (few) differences. | |
43 | ;; | |
44 | ;; In the mean time, this package offers most of the advantages of | |
45 | ;; full inheritance with the existing major modes. The macro | |
46 | ;; `define-derived-mode' allows the user to make a variant of an existing | |
47 | ;; major mode, with its own keymap. The new mode will inherit the key | |
48 | ;; bindings of its parent, and will, in fact, run its parent first | |
49 | ;; every time it is called. For example, the commands | |
50 | ;; | |
51 | ;; (define-derived-mode hypertext-mode text-mode "Hypertext" | |
52 | ;; "Major mode for hypertext.\n\n\\{hypertext-mode-map}" | |
53 | ;; (setq case-fold-search nil)) | |
54 | ;; | |
55 | ;; (define-key hypertext-mode-map [down-mouse-3] 'do-hyper-link) | |
56 | ;; | |
57 | ;; will create a function `hypertext-mode' with its own (sparse) | |
58 | ;; keymap `hypertext-mode-map.' The command M-x hypertext-mode will | |
59 | ;; perform the following actions: | |
60 | ;; | |
61 | ;; - run the command (text-mode) to get its default setup | |
62 | ;; - replace the current keymap with 'hypertext-mode-map,' which will | |
63 | ;; inherit from 'text-mode-map'. | |
64 | ;; - replace the current syntax table with | |
65 | ;; 'hypertext-mode-syntax-table', which will borrow its defaults | |
66 | ;; from the current text-mode-syntax-table. | |
67 | ;; - replace the current abbrev table with | |
68 | ;; 'hypertext-mode-abbrev-table', which will borrow its defaults | |
69 | ;; from the current text-mode-abbrev table | |
70 | ;; - change the mode line to read "Hypertext" | |
71 | ;; - assign the value 'hypertext-mode' to the 'major-mode' variable | |
72 | ;; - run the body of commands provided in the macro -- in this case, | |
73 | ;; set the local variable `case-fold-search' to nil. | |
74 | ;; | |
75 | ;; The advantages of this system are threefold. First, text mode is | |
76 | ;; untouched -- if you had added the new keystroke to `text-mode-map,' | |
77 | ;; possibly using hooks, you would have added it to all text buffers | |
78 | ;; -- here, it appears only in hypertext buffers, where it makes | |
79 | ;; sense. Second, it is possible to build even further, and make | |
80 | ;; a derived mode from a derived mode. The commands | |
81 | ;; | |
82 | ;; (define-derived-mode html-mode hypertext-mode "HTML") | |
83 | ;; [various key definitions] | |
84 | ;; | |
85 | ;; will add a new major mode for HTML with very little fuss. | |
86 | ;; | |
87 | ;; Note also the function `derived-mode-p' which can tell if the current | |
88 | ;; mode derives from another. In a hypertext-mode, buffer, for example, | |
89 | ;; (derived-mode-p 'text-mode) would return non-nil. This should always | |
90 | ;; be used in place of (eq major-mode 'text-mode). | |
91 | \f | |
92 | ;;; Code: | |
93 | ||
5e046f6d JB |
94 | ;;; PRIVATE: defsubst must be defined before they are first used |
95 | ||
96 | (defsubst derived-mode-hook-name (mode) | |
fea34e9f | 97 | "Construct a mode-hook name based on a MODE name." |
5e046f6d JB |
98 | (intern (concat (symbol-name mode) "-hook"))) |
99 | ||
100 | (defsubst derived-mode-map-name (mode) | |
101 | "Construct a map name based on a MODE name." | |
102 | (intern (concat (symbol-name mode) "-map"))) | |
103 | ||
104 | (defsubst derived-mode-syntax-table-name (mode) | |
105 | "Construct a syntax-table name based on a MODE name." | |
106 | (intern (concat (symbol-name mode) "-syntax-table"))) | |
107 | ||
108 | (defsubst derived-mode-abbrev-table-name (mode) | |
109 | "Construct an abbrev-table name based on a MODE name." | |
110 | (intern (concat (symbol-name mode) "-abbrev-table"))) | |
111 | ||
112 | ;; PUBLIC: define a new major mode which inherits from an existing one. | |
113 | ||
114 | ;;;###autoload | |
115 | (defmacro define-derived-mode (child parent name &optional docstring &rest body) | |
116 | "Create a new mode as a variant of an existing mode. | |
117 | ||
118 | The arguments to this command are as follow: | |
119 | ||
120 | CHILD: the name of the command for the derived mode. | |
121 | PARENT: the name of the command for the parent mode (e.g. `text-mode') | |
122 | or nil if there is no parent. | |
123 | NAME: a string which will appear in the status line (e.g. \"Hypertext\") | |
124 | DOCSTRING: an optional documentation string--if you do not supply one, | |
125 | the function will attempt to invent something useful. | |
126 | BODY: forms to execute just before running the | |
127 | hooks for the new mode. Do not use `interactive' here. | |
128 | ||
129 | BODY can start with a bunch of keyword arguments. The following keyword | |
130 | arguments are currently understood: | |
131 | :group GROUP | |
132 | Declare the customization group that corresponds to this mode. | |
3e2c3ab0 | 133 | The command `customize-mode' uses this. |
5e046f6d | 134 | :syntax-table TABLE |
b2948976 | 135 | Use TABLE instead of the default (CHILD-syntax-table). |
5e046f6d JB |
136 | A nil value means to simply use the same syntax-table as the parent. |
137 | :abbrev-table TABLE | |
b2948976 | 138 | Use TABLE instead of the default (CHILD-abbrev-table). |
5e046f6d JB |
139 | A nil value means to simply use the same abbrev-table as the parent. |
140 | ||
141 | Here is how you could define LaTeX-Thesis mode as a variant of LaTeX mode: | |
142 | ||
143 | (define-derived-mode LaTeX-thesis-mode LaTeX-mode \"LaTeX-Thesis\") | |
144 | ||
145 | You could then make new key bindings for `LaTeX-thesis-mode-map' | |
146 | without changing regular LaTeX mode. In this example, BODY is empty, | |
147 | and DOCSTRING is generated by default. | |
148 | ||
149 | On a more complicated level, the following command uses `sgml-mode' as | |
150 | the parent, and then sets the variable `case-fold-search' to nil: | |
151 | ||
152 | (define-derived-mode article-mode sgml-mode \"Article\" | |
153 | \"Major mode for editing technical articles.\" | |
154 | (setq case-fold-search nil)) | |
155 | ||
156 | Note that if the documentation string had been left out, it would have | |
8d11b450 GM |
157 | been generated automatically, with a reference to the keymap. |
158 | ||
159 | The new mode runs the hook constructed by the function | |
a5079d40 LT |
160 | `derived-mode-hook-name'. |
161 | ||
162 | See Info node `(elisp)Derived Modes' for more details." | |
5e046f6d | 163 | (declare (debug (&define name symbolp sexp [&optional stringp] |
a86a1609 JPW |
164 | [&rest keywordp sexp] def-body)) |
165 | (doc-string 4)) | |
5e046f6d JB |
166 | |
167 | (when (and docstring (not (stringp docstring))) | |
168 | ;; Some trickiness, since what appears to be the docstring may really be | |
169 | ;; the first element of the body. | |
170 | (push docstring body) | |
171 | (setq docstring nil)) | |
172 | ||
173 | (when (eq parent 'fundamental-mode) (setq parent nil)) | |
174 | ||
175 | (let ((map (derived-mode-map-name child)) | |
176 | (syntax (derived-mode-syntax-table-name child)) | |
177 | (abbrev (derived-mode-abbrev-table-name child)) | |
178 | (declare-abbrev t) | |
179 | (declare-syntax t) | |
180 | (hook (derived-mode-hook-name child)) | |
181 | (group nil)) | |
182 | ||
183 | ;; Process the keyword args. | |
184 | (while (keywordp (car body)) | |
f80efb86 SM |
185 | (pcase (pop body) |
186 | (`:group (setq group (pop body))) | |
187 | (`:abbrev-table (setq abbrev (pop body)) (setq declare-abbrev nil)) | |
188 | (`:syntax-table (setq syntax (pop body)) (setq declare-syntax nil)) | |
189 | (_ (pop body)))) | |
5e046f6d JB |
190 | |
191 | (setq docstring (derived-mode-make-docstring | |
192 | parent child docstring syntax abbrev)) | |
193 | ||
194 | `(progn | |
7f17cc40 SM |
195 | (defvar ,hook nil |
196 | ,(format "Hook run after entering %s mode. | |
156680e2 LT |
197 | No problems result if this variable is not bound. |
198 | `add-hook' automatically binds it. (This is true for all hook variables.)" | |
7f17cc40 | 199 | name)) |
cc793355 JL |
200 | (unless (boundp ',map) |
201 | (put ',map 'definition-name ',child)) | |
9d0da923 | 202 | (with-no-warnings (defvar ,map (make-sparse-keymap))) |
b43704f2 GM |
203 | (unless (get ',map 'variable-documentation) |
204 | (put ',map 'variable-documentation | |
a7610c52 | 205 | (purecopy ,(format "Keymap for `%s'." child)))) |
5e046f6d | 206 | ,(if declare-syntax |
cc793355 JL |
207 | `(progn |
208 | (unless (boundp ',syntax) | |
209 | (put ',syntax 'definition-name ',child)) | |
b43704f2 GM |
210 | (defvar ,syntax (make-syntax-table)) |
211 | (unless (get ',syntax 'variable-documentation) | |
212 | (put ',syntax 'variable-documentation | |
a7610c52 | 213 | (purecopy ,(format "Syntax table for `%s'." child)))))) |
5e046f6d | 214 | ,(if declare-abbrev |
cc793355 JL |
215 | `(progn |
216 | (put ',abbrev 'definition-name ',child) | |
217 | (defvar ,abbrev | |
6726c25e GM |
218 | (progn (define-abbrev-table ',abbrev nil) ,abbrev)) |
219 | (unless (get ',abbrev 'variable-documentation) | |
220 | (put ',abbrev 'variable-documentation | |
a7610c52 | 221 | (purecopy ,(format "Abbrev table for `%s'." child)))))) |
5e046f6d JB |
222 | (put ',child 'derived-mode-parent ',parent) |
223 | ,(if group `(put ',child 'custom-mode-group ,group)) | |
224 | ||
225 | (defun ,child () | |
226 | ,docstring | |
227 | (interactive) | |
228 | ; Run the parent. | |
229 | (delay-mode-hooks | |
230 | ||
15de15c6 | 231 | (,(or parent 'kill-all-local-variables)) |
5e046f6d JB |
232 | ; Identify the child mode. |
233 | (setq major-mode (quote ,child)) | |
234 | (setq mode-name ,name) | |
235 | ; Identify special modes. | |
236 | ,(when parent | |
237 | `(progn | |
238 | (if (get (quote ,parent) 'mode-class) | |
239 | (put (quote ,child) 'mode-class | |
240 | (get (quote ,parent) 'mode-class))) | |
241 | ; Set up maps and tables. | |
242 | (unless (keymap-parent ,map) | |
84ae4908 SM |
243 | ;; It would probably be better to set the keymap's parent |
244 | ;; at the toplevel rather than inside the mode function, | |
245 | ;; but this is not easy for at least the following reasons: | |
246 | ;; - the parent (and its keymap) may not yet be loaded. | |
247 | ;; - the parent's keymap name may be called something else | |
248 | ;; than <parent>-mode-map. | |
5e046f6d JB |
249 | (set-keymap-parent ,map (current-local-map))) |
250 | ,(when declare-syntax | |
251 | `(let ((parent (char-table-parent ,syntax))) | |
252 | (unless (and parent | |
253 | (not (eq parent (standard-syntax-table)))) | |
1a1e3f32 SM |
254 | (set-char-table-parent ,syntax (syntax-table))))) |
255 | ,(when declare-abbrev | |
450a0f09 SM |
256 | `(unless (or (abbrev-table-get ,abbrev :parents) |
257 | ;; This can happen if the major mode defines | |
258 | ;; the abbrev-table to be its parent's. | |
259 | (eq ,abbrev local-abbrev-table)) | |
1a1e3f32 SM |
260 | (abbrev-table-put ,abbrev :parents |
261 | (list local-abbrev-table)))))) | |
5e046f6d JB |
262 | (use-local-map ,map) |
263 | ,(when syntax `(set-syntax-table ,syntax)) | |
264 | ,(when abbrev `(setq local-abbrev-table ,abbrev)) | |
265 | ; Splice in the body (if any). | |
266 | ,@body | |
267 | ) | |
268 | ;; Run the hooks, if any. | |
cdcfbcb2 | 269 | (run-mode-hooks ',hook))))) |
5e046f6d JB |
270 | |
271 | ;; PUBLIC: find the ultimate class of a derived mode. | |
272 | ||
273 | (defun derived-mode-class (mode) | |
274 | "Find the class of a major MODE. | |
275 | A mode's class is the first ancestor which is NOT a derived mode. | |
276 | Use the `derived-mode-parent' property of the symbol to trace backwards. | |
277 | Since major-modes might all derive from `fundamental-mode', this function | |
278 | is not very useful." | |
59f7af81 | 279 | (declare (obsolete derived-mode-p "22.1")) |
5e046f6d JB |
280 | (while (get mode 'derived-mode-parent) |
281 | (setq mode (get mode 'derived-mode-parent))) | |
282 | mode) | |
5e046f6d JB |
283 | |
284 | \f | |
285 | ;;; PRIVATE | |
286 | ||
287 | (defun derived-mode-make-docstring (parent child &optional | |
288 | docstring syntax abbrev) | |
289 | "Construct a docstring for a new mode if none is provided." | |
290 | ||
291 | (let ((map (derived-mode-map-name child)) | |
292 | (hook (derived-mode-hook-name child))) | |
293 | ||
294 | (unless (stringp docstring) | |
295 | ;; Use a default docstring. | |
296 | (setq docstring | |
297 | (if (null parent) | |
48d6d9c0 GM |
298 | ;; FIXME filling. |
299 | (format "Major-mode.\nUses keymap `%s'%s%s." map | |
300 | (if abbrev (format "%s abbrev table `%s'" | |
301 | (if syntax "," " and") abbrev) "") | |
302 | (if syntax (format " and syntax-table `%s'" syntax) "")) | |
5e046f6d | 303 | (format "Major mode derived from `%s' by `define-derived-mode'. |
48d6d9c0 GM |
304 | It inherits all of the parent's attributes, but has its own keymap%s: |
305 | ||
306 | `%s'%s | |
307 | ||
308 | which more-or-less shadow%s %s's corresponding table%s." | |
309 | parent | |
310 | (cond ((and abbrev syntax) | |
311 | ",\nabbrev table and syntax table") | |
312 | (abbrev "\nand abbrev table") | |
313 | (syntax "\nand syntax table") | |
314 | (t "")) | |
315 | map | |
316 | (cond ((and abbrev syntax) | |
317 | (format ", `%s' and `%s'" abbrev syntax)) | |
318 | ((or abbrev syntax) | |
319 | (format " and `%s'" (or abbrev syntax))) | |
320 | (t "")) | |
321 | (if (or abbrev syntax) "" "s") | |
322 | parent | |
323 | (if (or abbrev syntax) "s" ""))))) | |
5e046f6d JB |
324 | |
325 | (unless (string-match (regexp-quote (symbol-name hook)) docstring) | |
326 | ;; Make sure the docstring mentions the mode's hook. | |
327 | (setq docstring | |
328 | (concat docstring | |
329 | (if (null parent) | |
330 | "\n\nThis mode " | |
331 | (concat | |
332 | "\n\nIn addition to any hooks its parent mode " | |
333 | (if (string-match (regexp-quote (format "`%s'" parent)) | |
334 | docstring) nil | |
335 | (format "`%s' " parent)) | |
336 | "might have run,\nthis mode ")) | |
337 | (format "runs the hook `%s'" hook) | |
338 | ", as the final step\nduring initialization."))) | |
339 | ||
340 | (unless (string-match "\\\\[{[]" docstring) | |
341 | ;; And don't forget to put the mode's keymap. | |
342 | (setq docstring (concat docstring "\n\n\\{" (symbol-name map) "}"))) | |
343 | ||
344 | docstring)) | |
345 | ||
346 | \f | |
347 | ;;; OBSOLETE | |
348 | ;; The functions below are only provided for backward compatibility with | |
349 | ;; code byte-compiled with versions of derived.el prior to Emacs-21. | |
350 | ||
351 | (defsubst derived-mode-setup-function-name (mode) | |
352 | "Construct a setup-function name based on a MODE name." | |
353 | (intern (concat (symbol-name mode) "-setup"))) | |
354 | ||
355 | \f | |
356 | ;; Utility functions for defining a derived mode. | |
357 | ||
358 | ;;;###autoload | |
359 | (defun derived-mode-init-mode-variables (mode) | |
a9873dbb | 360 | "Initialize variables for a new MODE. |
5e046f6d JB |
361 | Right now, if they don't already exist, set up a blank keymap, an |
362 | empty syntax table, and an empty abbrev table -- these will be merged | |
363 | the first time the mode is used." | |
364 | ||
365 | (if (boundp (derived-mode-map-name mode)) | |
366 | t | |
367 | (eval `(defvar ,(derived-mode-map-name mode) | |
368 | (make-sparse-keymap) | |
369 | ,(format "Keymap for %s." mode))) | |
370 | (put (derived-mode-map-name mode) 'derived-mode-unmerged t)) | |
371 | ||
372 | (if (boundp (derived-mode-syntax-table-name mode)) | |
373 | t | |
374 | (eval `(defvar ,(derived-mode-syntax-table-name mode) | |
375 | ;; Make a syntax table which doesn't specify anything | |
376 | ;; for any char. Valid data will be merged in by | |
377 | ;; derived-mode-merge-syntax-tables. | |
378 | (make-char-table 'syntax-table nil) | |
379 | ,(format "Syntax table for %s." mode))) | |
380 | (put (derived-mode-syntax-table-name mode) 'derived-mode-unmerged t)) | |
381 | ||
382 | (if (boundp (derived-mode-abbrev-table-name mode)) | |
383 | t | |
384 | (eval `(defvar ,(derived-mode-abbrev-table-name mode) | |
385 | (progn | |
386 | (define-abbrev-table (derived-mode-abbrev-table-name mode) nil) | |
387 | (make-abbrev-table)) | |
388 | ,(format "Abbrev table for %s." mode))))) | |
389 | \f | |
390 | ;; Utility functions for running a derived mode. | |
391 | ||
392 | (defun derived-mode-set-keymap (mode) | |
393 | "Set the keymap of the new MODE, maybe merging with the parent." | |
394 | (let* ((map-name (derived-mode-map-name mode)) | |
395 | (new-map (eval map-name)) | |
396 | (old-map (current-local-map))) | |
397 | (and old-map | |
398 | (get map-name 'derived-mode-unmerged) | |
399 | (derived-mode-merge-keymaps old-map new-map)) | |
400 | (put map-name 'derived-mode-unmerged nil) | |
401 | (use-local-map new-map))) | |
402 | ||
403 | (defun derived-mode-set-syntax-table (mode) | |
404 | "Set the syntax table of the new MODE, maybe merging with the parent." | |
405 | (let* ((table-name (derived-mode-syntax-table-name mode)) | |
406 | (old-table (syntax-table)) | |
407 | (new-table (eval table-name))) | |
408 | (if (get table-name 'derived-mode-unmerged) | |
409 | (derived-mode-merge-syntax-tables old-table new-table)) | |
410 | (put table-name 'derived-mode-unmerged nil) | |
411 | (set-syntax-table new-table))) | |
412 | ||
413 | (defun derived-mode-set-abbrev-table (mode) | |
414 | "Set the abbrev table for MODE if it exists. | |
415 | Always merge its parent into it, since the merge is non-destructive." | |
416 | (let* ((table-name (derived-mode-abbrev-table-name mode)) | |
417 | (old-table local-abbrev-table) | |
418 | (new-table (eval table-name))) | |
419 | (derived-mode-merge-abbrev-tables old-table new-table) | |
420 | (setq local-abbrev-table new-table))) | |
421 | ||
3c8dd9b9 JB |
422 | (defun derived-mode-run-hooks (mode) |
423 | "Run the mode hook for MODE." | |
424 | (let ((hooks-name (derived-mode-hook-name mode))) | |
425 | (if (boundp hooks-name) | |
426 | (run-hooks hooks-name)))) | |
427 | ||
5e046f6d JB |
428 | ;; Functions to merge maps and tables. |
429 | ||
430 | (defun derived-mode-merge-keymaps (old new) | |
431 | "Merge an OLD keymap into a NEW one. | |
432 | The old keymap is set to be the last cdr of the new one, so that there will | |
433 | be automatic inheritance." | |
434 | ;; ?? Can this just use `set-keymap-parent'? | |
435 | (let ((tail new)) | |
436 | ;; Scan the NEW map for prefix keys. | |
437 | (while (consp tail) | |
438 | (and (consp (car tail)) | |
439 | (let* ((key (vector (car (car tail)))) | |
440 | (subnew (lookup-key new key)) | |
441 | (subold (lookup-key old key))) | |
442 | ;; If KEY is a prefix key in both OLD and NEW, merge them. | |
443 | (and (keymapp subnew) (keymapp subold) | |
444 | (derived-mode-merge-keymaps subold subnew)))) | |
445 | (and (vectorp (car tail)) | |
446 | ;; Search a vector of ASCII char bindings for prefix keys. | |
447 | (let ((i (1- (length (car tail))))) | |
448 | (while (>= i 0) | |
449 | (let* ((key (vector i)) | |
450 | (subnew (lookup-key new key)) | |
451 | (subold (lookup-key old key))) | |
452 | ;; If KEY is a prefix key in both OLD and NEW, merge them. | |
453 | (and (keymapp subnew) (keymapp subold) | |
454 | (derived-mode-merge-keymaps subold subnew))) | |
455 | (setq i (1- i))))) | |
456 | (setq tail (cdr tail)))) | |
457 | (setcdr (nthcdr (1- (length new)) new) old)) | |
458 | ||
459 | (defun derived-mode-merge-syntax-tables (old new) | |
460 | "Merge an OLD syntax table into a NEW one. | |
461 | Where the new table already has an entry, nothing is copied from the old one." | |
462 | (set-char-table-parent new old)) | |
463 | ||
464 | ;; Merge an old abbrev table into a new one. | |
465 | ;; This function requires internal knowledge of how abbrev tables work, | |
466 | ;; presuming that they are obarrays with the abbrev as the symbol, the expansion | |
467 | ;; as the value of the symbol, and the hook as the function definition. | |
468 | (defun derived-mode-merge-abbrev-tables (old new) | |
469 | (if old | |
470 | (mapatoms | |
471 | (lambda (symbol) | |
472 | (or (intern-soft (symbol-name symbol) new) | |
473 | (define-abbrev new (symbol-name symbol) | |
474 | (symbol-value symbol) (symbol-function symbol)))) | |
475 | old))) | |
476 | ||
477 | (provide 'derived) | |
478 | ||
479 | ;;; derived.el ends here |