1 ;;; poe.el --- Emulation module for each Emacs variants
3 ;; Copyright (C) 1995,1996,1997,1998 Free Software Foundation, Inc.
5 ;; Author: MORIOKA Tomohiko <morioka@jaist.ac.jp>
6 ;; Keywords: emulation, compatibility, NEmacs, MULE, Emacs/mule, XEmacs
8 ;; This file is part of APEL (A Portable Emacs Library).
10 ;; This program is free software; you can redistribute it and/or
11 ;; modify it under the terms of the GNU General Public License as
12 ;; published by the Free Software Foundation; either version 2, or (at
13 ;; your option) any later version.
15 ;; This program is distributed in the hope that it will be useful, but
16 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 ;; General Public License for more details.
20 ;; You should have received a copy of the GNU General Public License
21 ;; along with GNU Emacs; see the file COPYING. If not, write to the
22 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 ;; Boston, MA 02111-1307, USA.
27 (defmacro defun-maybe (name &rest everything-else)
28 (or (and (fboundp name)
29 (not (get name 'defun-maybe))
31 (` (or (fboundp (quote (, name)))
33 (defun (, name) (,@ everything-else))
34 (put (quote (, name)) 'defun-maybe t)
38 (defmacro defsubst-maybe (name &rest everything-else)
39 (or (and (fboundp name)
40 (not (get name 'defsubst-maybe))
42 (` (or (fboundp (quote (, name)))
44 (defsubst (, name) (,@ everything-else))
45 (put (quote (, name)) 'defsubst-maybe t)
49 (defmacro defmacro-maybe (name &rest everything-else)
50 (or (and (fboundp name)
51 (not (get name 'defmacro-maybe))
53 (` (or (fboundp (quote (, name)))
55 (defmacro (, name) (,@ everything-else))
56 (put (quote (, name)) 'defmacro-maybe t)
60 (put 'defun-maybe 'lisp-indent-function 'defun)
61 (put 'defsubst-maybe 'lisp-indent-function 'defun)
62 (put 'defmacro-maybe 'lisp-indent-function 'defun)
64 (defmacro defconst-maybe (name &rest everything-else)
65 (or (and (boundp name)
66 (not (get name 'defconst-maybe))
68 (` (or (boundp (quote (, name)))
70 (defconst (, name) (,@ everything-else))
71 (put (quote (, name)) 'defconst-maybe t)
75 (defconst-maybe emacs-major-version (string-to-int emacs-version))
76 (defconst-maybe emacs-minor-version
78 (substring emacs-version
79 (string-match (format "%d\\." emacs-major-version)
82 (cond ((featurep 'xemacs)
85 ((string-match "XEmacs" emacs-version)
89 ((>= emacs-major-version 19)
97 ;;; @ Emacs 19 emulation
100 (defun-maybe minibuffer-prompt-width ()
101 "Return the display width of the minibuffer prompt."
103 (set-buffer (window-buffer (minibuffer-window)))
107 ;;; @ Emacs 19.29 emulation
110 (defvar path-separator ":"
111 "Character used to separate concatenated paths.")
113 (defun-maybe buffer-substring-no-properties (start end)
114 "Return the characters of part of the buffer, without the text properties.
115 The two arguments START and END are character positions;
116 they can be in either order. [Emacs 19.29 emulating function]"
117 (let ((string (buffer-substring start end)))
118 (set-text-properties 0 (length string) nil string)
121 (defun-maybe match-string (num &optional string)
122 "Return string of text matched by last search.
123 NUM specifies which parenthesized expression in the last regexp.
124 Value is nil if NUMth pair didn't match, or there were less than NUM pairs.
125 Zero means the entire text matched by the whole regexp or whole string.
126 STRING should be given if the last search was by `string-match' on STRING.
127 \[Emacs 19.29 emulating function]"
128 (if (match-beginning num)
130 (substring string (match-beginning num) (match-end num))
131 (buffer-substring (match-beginning num) (match-end num)))))
133 (or (featurep 'xemacs)
134 (>= emacs-major-version 20)
135 (and (= emacs-major-version 19)
136 (>= emacs-minor-version 29))
137 ;; for Emacs 19.28 or earlier
138 (fboundp 'si:read-string)
140 (fset 'si:read-string (symbol-function 'read-string))
142 (defun read-string (prompt &optional initial-input history)
143 "Read a string from the minibuffer, prompting with string PROMPT.
144 If non-nil, second arg INITIAL-INPUT is a string to insert before reading.
145 The third arg HISTORY, is dummy for compatibility. [emu.el]
146 See `read-from-minibuffer' for details of HISTORY argument."
147 (si:read-string prompt initial-input))
151 ;;; @ Emacs 19.30 emulation
154 ;; This function was imported Emacs 19.30.
155 (defun-maybe add-to-list (list-var element)
156 "Add to the value of LIST-VAR the element ELEMENT if it isn't there yet.
157 If you want to use `add-to-list' on a variable that is not defined
158 until a certain package is loaded, you should put the call to `add-to-list'
159 into a hook function that will be run only after loading the package.
160 \[Emacs 19.30 emulating function]"
161 (or (member element (symbol-value list-var))
162 (set list-var (cons element (symbol-value list-var)))))
164 (cond ((fboundp 'insert-file-contents-literally))
165 ((boundp 'file-name-handler-alist)
166 (defun insert-file-contents-literally
167 (filename &optional visit beg end replace)
168 "Like `insert-file-contents', q.v., but only reads in the file.
169 A buffer may be modified in several ways after reading into the buffer due
170 to advanced Emacs features, such as file-name-handlers, format decoding,
171 find-file-hooks, etc.
172 This function ensures that none of these modifications will take place.
173 \[Emacs 19.30 emulating function]"
174 (let (file-name-handler-alist)
175 (insert-file-contents filename visit beg end replace)))
178 (defalias 'insert-file-contents-literally 'insert-file-contents)
182 ;;; @ Emacs 19.31 emulation
185 (defun-maybe buffer-live-p (object)
186 "Return non-nil if OBJECT is a buffer which has not been killed.
187 Value is nil if OBJECT is not a buffer or if it has been killed.
188 \[Emacs 19.31 emulating function]"
191 (buffer-name (get-buffer object))))
193 ;; This macro was imported Emacs 19.33.
194 (defmacro-maybe save-selected-window (&rest body)
195 "Execute BODY, then select the window that was selected before BODY.
196 \[Emacs 19.31 emulating function]"
198 '((save-selected-window-window (selected-window)))
199 (list 'unwind-protect
201 (list 'select-window 'save-selected-window-window))))
204 ;;; @ Emacs 20.1 emulation
207 ;; This macro was imported Emacs 20.2.
208 (defmacro-maybe when (cond &rest body)
209 "(when COND BODY...): if COND yields non-nil, do BODY, else return nil."
210 (list 'if cond (cons 'progn body)))
212 (defmacro-maybe save-current-buffer (&rest body)
213 "Save the current buffer; execute BODY; restore the current buffer.
214 Executes BODY just like `progn'."
215 (` (let ((orig-buffer (current-buffer)))
218 (set-buffer orig-buffer)))))
220 ;; This macro was imported Emacs 20.2.
221 (defmacro-maybe with-current-buffer (buffer &rest body)
222 "Execute the forms in BODY with BUFFER as the current buffer.
223 The value returned is the value of the last form in BODY.
224 See also `with-temp-buffer'."
225 (` (save-current-buffer
226 (set-buffer (, buffer))
229 ;; This macro was imported Emacs 20.2.
230 (defmacro-maybe with-temp-file (file &rest forms)
231 "Create a new buffer, evaluate FORMS there, and write the buffer to FILE.
232 The value of the last form in FORMS is returned, like `progn'.
233 See also `with-temp-buffer'."
234 (let ((temp-file (make-symbol "temp-file"))
235 (temp-buffer (make-symbol "temp-buffer")))
236 (` (let (((, temp-file) (, file))
238 (get-buffer-create (generate-new-buffer-name " *temp file*"))))
241 (with-current-buffer (, temp-buffer)
243 (with-current-buffer (, temp-buffer)
245 (write-region (point-min) (point-max) (, temp-file) nil 0)))
246 (and (buffer-name (, temp-buffer))
247 (kill-buffer (, temp-buffer))))))))
249 ;; This macro was imported Emacs 20.2.
250 (defmacro-maybe with-temp-buffer (&rest forms)
251 "Create a temporary buffer, and evaluate FORMS there like `progn'.
252 See also `with-temp-file' and `with-output-to-string'."
253 (let ((temp-buffer (make-symbol "temp-buffer")))
254 (` (let (((, temp-buffer)
255 (get-buffer-create (generate-new-buffer-name " *temp*"))))
257 (with-current-buffer (, temp-buffer)
259 (and (buffer-name (, temp-buffer))
260 (kill-buffer (, temp-buffer))))))))
262 ;; This function was imported Emacs 20.3.
263 (defun-maybe last (x &optional n)
264 "Return the last link of the list X. Its car is the last element.
265 If X is nil, return nil.
266 If N is non-nil, return the Nth-to-last link of X.
267 If N is bigger than the length of X, return X."
271 (setq m (1+ m) p (cdr p)))
273 (if (< n m) (nthcdr (- m n) x) x)))
278 ;; This function was imported Emacs 20.3. (cl function)
279 (defun-maybe butlast (x &optional n)
280 "Returns a copy of LIST with the last N elements removed."
281 (if (and n (<= n 0)) x
282 (nbutlast (copy-sequence x) n)))
284 ;; This function was imported Emacs 20.3. (cl function)
285 (defun-maybe nbutlast (x &optional n)
286 "Modifies LIST to remove the last N elements."
287 (let ((m (length x)))
291 (if (> n 0) (setcdr (nthcdr (- (1- m) n) x) nil))
294 ;; This function was imported from XEmacs 21.
295 (defun-maybe split-string (string &optional pattern)
296 "Return a list of substrings of STRING which are separated by PATTERN.
297 If PATTERN is omitted, it defaults to \"[ \\f\\t\\n\\r\\v]+\"."
299 (setq pattern "[ \f\t\n\r\v]+"))
300 ;; The FSF version of this function takes care not to cons in case
301 ;; of infloop. Maybe we should synch?
302 (let (parts (start 0))
303 (while (string-match pattern string start)
304 (setq parts (cons (substring string start (match-beginning 0)) parts)
305 start (match-end 0)))
306 (nreverse (cons (substring string start) parts))))
309 ;;; @ Emacs 20.3 emulation
312 (defun-maybe line-beginning-position (&optional n)
313 "Return the character position of the first character on the current line.
314 With argument N not nil or 1, move forward N - 1 lines first.
315 If scan reaches end of buffer, return that position.
316 This function does not move point."
319 (forward-line (1- n))
324 (defun-maybe line-end-position (&optional n)
325 "Return the character position of the last character on the current line.
326 With argument N not nil or 1, move forward N - 1 lines first.
327 If scan reaches end of buffer, return that position.
328 This function does not move point."
331 (forward-line (1- n))
337 ;;; @ XEmacs emulation
340 (defun-maybe point-at-bol (&optional n buffer)
341 "Return the character position of the first character on the current line.
342 With argument N not nil or 1, move forward N - 1 lines first.
343 If scan reaches end of buffer, return that position.
344 This function does not move point. [XEmacs emulating function]"
349 (line-beginning-position n)
352 (defun-maybe point-at-eol (&optional n buffer)
353 "Return the character position of the last character on the current line.
354 With argument N not nil or 1, move forward N - 1 lines first.
355 If scan reaches end of buffer, return that position.
356 This function does not move point. [XEmacs emulating function]"
361 (line-end-position n)
364 (defun-maybe functionp (obj)
365 "Returns t if OBJ is a function, nil otherwise.
366 \[XEmacs emulating function]"
368 (byte-code-function-p obj)
369 (and (symbolp obj)(fboundp obj))
370 (and (consp obj)(eq (car obj) 'lambda))