1 ;;; poe.el --- Portable Outfit for Emacsen
3 ;; Copyright (C) 1995,1996,1997,1998,1999 Free Software Foundation, Inc.
5 ;; Author: MORIOKA Tomohiko <tomo@m17n.org>
6 ;; Shuhei KOBAYASHI <shuhei@aqua.ocn.ne.jp>
7 ;; Keywords: emulation, compatibility, Nemacs, MULE, Emacs/mule, XEmacs
9 ;; This file is part of APEL (A Portable Emacs Library).
11 ;; This program is free software; you can redistribute it and/or
12 ;; modify it under the terms of the GNU General Public License as
13 ;; published by the Free Software Foundation; either version 2, or (at
14 ;; your option) any later version.
16 ;; This program is distributed in the hope that it will be useful, but
17 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 ;; 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.
30 (provide 'poe) ; beware of circular dependency.
31 ; localhook.el depends on poe.el.
32 (require 'pym) ; `static-*' and `def*-maybe'.
35 ;;; @ Version information.
38 (defconst-maybe emacs-major-version
39 (progn (string-match "^[0-9]+" emacs-version)
40 (string-to-int (substring emacs-version
41 (match-beginning 0)(match-end 0))))
42 "Major version number of this version of Emacs.")
44 (defconst-maybe emacs-minor-version
45 (progn (string-match "^[0-9]+\\.\\([0-9]+\\)" emacs-version)
46 (string-to-int (substring emacs-version
47 (match-beginning 1)(match-end 1))))
48 "Minor version number of this version of Emacs.")
50 (static-when (= emacs-major-version 18)
53 ;; Some ancient version of XEmacs did not provide 'xemacs.
54 (static-when (string-match "XEmacs" emacs-version)
57 ;; `file-coding' was appeared in the spring of 1998, just before XEmacs
58 ;; 21.0. Therefore it is not provided in XEmacs with MULE versions 20.4
60 (static-when (featurep 'xemacs)
61 ;; must be load-time check to share .elc between w/ MULE and w/o MULE.
62 (when (featurep 'mule)
63 (provide 'file-coding)))
65 (static-when (featurep 'xemacs)
66 (require 'poe-xemacs))
69 ;;; @ C primitives emulation.
72 ;; (require FEATURE &optional FILENAME NOERROR)
73 ;; Emacs 20.4 and later takes optional 3rd arg NOERROR.
74 (static-condition-case nil
75 ;; compile-time check.
77 (require 'nofeature "nofile" 'noerror)
78 (if (get 'require 'defun-maybe)
79 (error ""))) ; already redefined.
82 (or (fboundp 'si:require)
84 (fset 'si:require (symbol-function 'require))
85 (put 'require 'defun-maybe t)
86 (defun require (feature &optional filename noerror)
88 If feature FEATURE is not loaded, load it from FILENAME.
89 If FEATURE is not a member of the list `features', then the feature
90 is not loaded; so load the file FILENAME.
91 If FILENAME is omitted, the printname of FEATURE is used as the file name,
92 but in this case `load' insists on adding the suffix `.el' or `.elc'.
93 If the optional third argument NOERROR is non-nil,
94 then return nil if the file is not found.
95 Normally the return value is FEATURE."
98 (si:require feature filename)
100 (si:require feature filename)))))))
102 ;; Emacs 19.29 and later: (plist-get PLIST PROP)
103 ;; (defun-maybe plist-get (plist prop)
105 ;; (not (eq (car plist) prop)))
106 ;; (setq plist (cdr (cdr plist))))
107 ;; (car (cdr plist)))
108 (static-unless (and (fboundp 'plist-get)
109 (not (get 'plist-get 'defun-maybe)))
110 (or (fboundp 'plist-get)
112 (defvar plist-get-internal-symbol)
113 (defun plist-get (plist prop)
115 Extract a value from a property list.
116 PLIST is a property list, which is a list of the form
117 \(PROP1 VALUE1 PROP2 VALUE2...\). This function returns the value
118 corresponding to the given PROP, or nil if PROP is not
119 one of the properties on the list."
120 (setplist 'plist-get-internal-symbol plist)
121 (get 'plist-get-internal-symbol prop))
122 (setq current-load-list (cons 'plist-get current-load-list))
123 (put 'plist-get 'defun-maybe t))))
125 ;; Emacs 19.29 and later: (plist-put PLIST PROP VAL)
126 ;; (defun-maybe plist-put (plist prop val)
128 ;; (let ((tail plist)
130 ;; (while (and tail (cdr tail))
131 ;; (if (eq (car tail) prop)
133 ;; (setcar (cdr tail) val)
134 ;; (throw 'found plist))
136 ;; tail (cdr (cdr tail)))))
139 ;; (setcdr (cdr prev) (list prop val))
141 ;; (list prop val)))))
142 (static-unless (and (fboundp 'plist-put)
143 (not (get 'plist-put 'defun-maybe)))
144 (or (fboundp 'plist-put)
146 (defvar plist-put-internal-symbol)
147 (defun plist-put (plist prop val)
149 Change value in PLIST of PROP to VAL.
150 PLIST is a property list, which is a list of the form
151 \(PROP1 VALUE1 PROP2 VALUE2 ...\). PROP is a symbol and VAL is any object.
152 If PROP is already a property on the list, its value is set to VAL,
153 otherwise the new PROP VAL pair is added. The new plist is returned;
154 use `\(setq x \(plist-put x prop val\)\)' to be sure to use the new value.
155 The PLIST is modified by side effects."
156 (setplist 'plist-put-internal-symbol plist)
157 (put 'plist-put-internal-symbol prop val)
158 (symbol-plist 'plist-put-internal-symbol))
159 (setq current-load-list (cons 'plist-put current-load-list))
160 (put 'plist-put 'defun-maybe t))))
162 ;; Emacs 19.23 and later: (minibuffer-prompt-width)
163 (defun-maybe minibuffer-prompt-width ()
164 "Return the display width of the minibuffer prompt."
166 (set-buffer (window-buffer (minibuffer-window)))
169 ;; (read-string PROMPT &optional INITIAL-INPUT HISTORY)
170 ;; Emacs 19.29/XEmacs 19.14(?) and later takes optional 3rd arg HISTORY.
171 (static-unless (or (featurep 'xemacs)
172 (>= emacs-major-version 20)
173 (and (= emacs-major-version 19)
174 (>= emacs-minor-version 29)))
175 (or (fboundp 'si:read-string)
177 (fset 'si:read-string (symbol-function 'read-string))
178 (defun read-string (prompt &optional initial-input history)
180 Read a string from the minibuffer, prompting with string PROMPT.
181 If non-nil, second arg INITIAL-INPUT is a string to insert before reading.
182 The third arg HISTORY, is dummy for compatibility.
183 See `read-from-minibuffer' for details of HISTORY argument."
184 (si:read-string prompt initial-input)))))
186 ;; v18: (string-to-int STRING)
187 ;; v19: (string-to-number STRING)
188 ;; v20: (string-to-number STRING &optional BASE)
190 ;; XXX: `string-to-number' of Emacs 20.3 and earlier is broken.
191 ;; (string-to-number "1e1" 16) => 10.0, should be 481.
192 (static-condition-case nil
193 ;; compile-time check.
194 (if (= (string-to-number "1e1" 16) 481)
195 (if (get 'string-to-number 'defun-maybe)
196 (error "")) ; already redefined.
197 (error "")) ; Emacs 20.3 and ealier.
200 (or (fboundp 'si:string-to-number)
202 (if (fboundp 'string-to-number)
203 (fset 'si:string-to-number (symbol-function 'string-to-number))
204 (fset 'si:string-to-number (symbol-function 'string-to-int))
205 (defalias 'string-to-int 'string-to-number))
206 (put 'string-to-number 'defun-maybe t)
207 (defun string-to-number (string &optional base)
209 Convert STRING to a number by parsing it as a decimal number.
210 This parses both integers and floating point numbers.
211 It ignores leading spaces and tabs.
213 If BASE, interpret STRING as a number in that base. If BASE isn't
214 present, base 10 is used. BASE must be between 2 and 16 (inclusive).
215 If the base used is not 10, floating point is not recognized."
216 (if (or (null base) (= base 10))
217 (si:string-to-number string)
218 (if (or (< base 2)(> base 16))
219 (signal 'args-out-of-range (cons base nil)))
220 (let ((len (length string))
222 ;; skip leading whitespace.
223 (while (and (< pos len)
224 (memq (aref string pos) '(?\ ?\t)))
228 (let ((number 0)(negative 1)
230 (if (eq (aref string pos) ?-)
233 (if (eq (aref string pos) ?+)
234 (setq pos (1+ pos))))
235 (while (and (< pos len)
236 (setq chr (aref string pos)
238 ((and (<= ?0 chr)(<= chr ?9))
240 ((and (<= ?A chr)(<= chr ?F))
242 ((and (<= ?a chr)(<= chr ?f))
246 (setq number (+ (* number base) num)
248 (* negative number))))))))))
250 ;; Emacs 20.1 and 20.2: (concat-chars &rest CHARS)
251 ;; Emacs 20.3/XEmacs 21.0 and later: (string &rest CHARS)
253 ((and (fboundp 'string)
254 (subrp (symbol-function 'string)))
255 ;; Emacs 20.3/XEmacs 21.0 and later.
257 ((and (fboundp 'concat-chars)
258 (subrp (symbol-function 'concat-chars)))
259 ;; Emacs 20.1 and 20.2.
260 (defalias 'string 'concat-chars))
262 ;; Use `defun-maybe' to update `load-history'.
263 (defun-maybe string (&rest chars)
264 "Concatenate all the argument characters and make the result a string."
265 ;; We cannot use (apply 'concat chars) here because `concat' does not
266 ;; work with multibyte chars on Mule 1.* and 2.*.
267 (mapconcat (function char-to-string) chars ""))))
269 ;; Mule: (char-before POS)
270 ;; v20: (char-before &optional POS)
271 (static-condition-case nil
272 ;; compile-time check.
275 (if (get 'char-before 'defun-maybe)
276 (error ""))) ; already defined.
277 (wrong-number-of-arguments ; Mule.
279 (or (fboundp 'si:char-before)
281 (fset 'si:char-before (symbol-function 'char-before))
282 (put 'char-before 'defun-maybe t)
283 ;; takes IGNORED for backward compatibility.
284 (defun char-before (&optional pos ignored)
286 Return character in current buffer preceding position POS.
287 POS is an integer or a buffer pointer.
288 If POS is out of range, the value is nil."
289 (si:char-before (or pos (point)))))))
290 (void-function ; non-Mule.
292 (defun-maybe char-before (&optional pos)
294 Return character in current buffer preceding position POS.
295 POS is an integer or a buffer pointer.
296 If POS is out of range, the value is nil."
299 (and (= (goto-char pos) (point))
304 (error ; found our definition at compile-time.
308 (wrong-number-of-arguments ; Mule.
309 (or (fboundp 'si:char-before)
311 (fset 'si:char-before (symbol-function 'char-before))
312 (put 'char-before 'defun-maybe t)
313 ;; takes IGNORED for backward compatibility.
314 (defun char-before (&optional pos ignored)
316 Return character in current buffer preceding position POS.
317 POS is an integer or a buffer pointer.
318 If POS is out of range, the value is nil."
319 (si:char-before (or pos (point)))))))
320 (void-function ; non-Mule.
321 (defun-maybe char-before (&optional pos)
323 Return character in current buffer preceding position POS.
324 POS is an integer or a buffer pointer.
325 If POS is out of range, the value is nil."
328 (and (= (goto-char pos) (point))
332 (preceding-char))))))))
334 ;; v18, v19: (char-after POS)
335 ;; v20: (char-after &optional POS)
336 (static-condition-case nil
337 ;; compile-time check.
340 (if (get 'char-after 'defun-maybe)
341 (error ""))) ; already defined.
342 (wrong-number-of-arguments ; v18, v19
344 (or (fboundp 'si:char-after)
346 (fset 'si:char-after (symbol-function 'char-after))
347 (put 'char-after 'defun-maybe t)
348 (defun char-after (&optional pos)
350 Return character in current buffer at position POS.
351 POS is an integer or a buffer pointer.
352 If POS is out of range, the value is nil."
353 (si:char-after (or pos (point)))))))
354 (void-function ; NEVER happen?
356 (defun-maybe char-after (&optional pos)
358 Return character in current buffer at position POS.
359 POS is an integer or a buffer pointer.
360 If POS is out of range, the value is nil."
363 (and (= (goto-char pos) (point))
368 (error ; found our definition at compile-time.
372 (wrong-number-of-arguments ; v18, v19
373 (or (fboundp 'si:char-after)
375 (fset 'si:char-after (symbol-function 'char-after))
376 (put 'char-after 'defun-maybe t)
377 (defun char-after (&optional pos)
379 Return character in current buffer at position POS.
380 POS is an integer or a buffer pointer.
381 If POS is out of range, the value is nil."
382 (si:char-after (or pos (point)))))))
383 (void-function ; NEVER happen?
384 (defun-maybe char-after (&optional pos)
386 Return character in current buffer at position POS.
387 POS is an integer or a buffer pointer.
388 If POS is out of range, the value is nil."
391 (and (= (goto-char pos) (point))
395 (following-char))))))))
397 ;; Emacs 19.29 and later: (buffer-substring-no-properties START END)
398 (defun-maybe buffer-substring-no-properties (start end)
399 "Return the characters of part of the buffer, without the text properties.
400 The two arguments START and END are character positions;
401 they can be in either order."
402 (let ((string (buffer-substring start end)))
403 (set-text-properties 0 (length string) nil string)
406 ;; Emacs 19.31 and later: (buffer-live-p OBJECT)
407 (defun-maybe buffer-live-p (object)
408 "Return non-nil if OBJECT is a buffer which has not been killed.
409 Value is nil if OBJECT is not a buffer or if it has been killed."
412 (buffer-name (get-buffer object))
415 ;; Emacs 20: (line-beginning-position &optional N)
416 (defun-maybe line-beginning-position (&optional n)
417 "Return the character position of the first character on the current line.
418 With argument N not nil or 1, move forward N - 1 lines first.
419 If scan reaches end of buffer, return that position.
420 This function does not move point."
422 (forward-line (1- (or n 1)))
425 ;; Emacs 20: (line-end-position &optional N)
426 (defun-maybe line-end-position (&optional n)
427 "Return the character position of the last character on the current line.
428 With argument N not nil or 1, move forward N - 1 lines first.
429 If scan reaches end of buffer, return that position.
430 This function does not move point."
432 (end-of-line (or n 1))
436 ;;; @ Basic lisp subroutines emulation. (lisp/subr.el)
439 ;;; @@ Lisp language features.
441 (defmacro-maybe push (newelt listname)
442 "Add NEWELT to the list stored in the symbol LISTNAME.
443 This is equivalent to (setq LISTNAME (cons NEWELT LISTNAME)).
444 LISTNAME must be a symbol."
446 (list 'cons newelt listname)))
448 (defmacro-maybe pop (listname)
449 "Return the first element of LISTNAME's value, and remove it from the list.
450 LISTNAME must be a symbol whose value is a list.
451 If the value is nil, `pop' returns nil but does not actually
453 (list 'prog1 (list 'car listname)
454 (list 'setq listname (list 'cdr listname))))
456 (defmacro-maybe when (cond &rest body)
457 "If COND yields non-nil, do BODY, else return nil."
458 (list 'if cond (cons 'progn body)))
459 ;; (def-edebug-spec when (&rest form))
461 (defmacro-maybe unless (cond &rest body)
462 "If COND yields nil, do BODY, else return nil."
463 (cons 'if (cons cond (cons nil body))))
464 ;; (def-edebug-spec unless (&rest form))
466 (defsubst-maybe caar (x)
467 "Return the car of the car of X."
470 (defsubst-maybe cadr (x)
471 "Return the car of the cdr of X."
474 (defsubst-maybe cdar (x)
475 "Return the cdr of the car of X."
478 (defsubst-maybe cddr (x)
479 "Return the cdr of the cdr of X."
482 (defun-maybe last (x &optional n)
483 "Return the last link of the list X. Its car is the last element.
484 If X is nil, return nil.
485 If N is non-nil, return the Nth-to-last link of X.
486 If N is bigger than the length of X, return X."
490 (setq m (1+ m) p (cdr p)))
492 (if (< n m) (nthcdr (- m n) x) x)))
497 ;; Actually, `butlast' and `nbutlast' are defined in lisp/cl.el.
498 (defun-maybe butlast (x &optional n)
499 "Returns a copy of LIST with the last N elements removed."
500 (if (and n (<= n 0)) x
501 (nbutlast (copy-sequence x) n)))
503 (defun-maybe nbutlast (x &optional n)
504 "Modifies LIST to remove the last N elements."
505 (let ((m (length x)))
509 (if (> n 0) (setcdr (nthcdr (- (1- m) n) x) nil))
512 ;; Emacs 20.3 and later: (assoc-default KEY ALIST &optional TEST DEFAULT)
513 (defun-maybe assoc-default (key alist &optional test default)
514 "Find object KEY in a pseudo-alist ALIST.
515 ALIST is a list of conses or objects. Each element (or the element's car,
516 if it is a cons) is compared with KEY by evaluating (TEST (car elt) KEY).
517 If that is non-nil, the element matches;
518 then `assoc-default' returns the element's cdr, if it is a cons,
519 or DEFAULT if the element is not a cons.
521 If no element matches, the value is nil.
522 If TEST is omitted or nil, `equal' is used."
523 (let (found (tail alist) value)
524 (while (and tail (not found))
525 (let ((elt (car tail)))
526 (when (funcall (or test 'equal) (if (consp elt) (car elt) elt) key)
527 (setq found t value (if (consp elt) (cdr elt) default))))
528 (setq tail (cdr tail)))
531 ;; The following two function use `compare-strings', which we don't
533 ;; (defun assoc-ignore-case (key alist))
534 ;; (defun assoc-ignore-representation (key alist))
536 ;; Emacs 19.29/XEmacs 19.14(?) and later: (rassoc KEY LIST)
537 ;; Actually, `rassoc' is defined in src/fns.c.
538 (defun-maybe rassoc (key list)
539 "Return non-nil if KEY is `equal' to the cdr of an element of LIST.
540 The value is actually the element of LIST whose cdr equals KEY.
541 Elements of LIST that are not conses are ignored."
544 (cond ((not (consp (car list))))
545 ((equal (cdr (car list)) key)
546 (throw 'found (car list))))
547 (setq list (cdr list)))))
549 ;;; @@ Hook manipulation functions.
551 ;; "localhook" package is written for Emacs 19.28 and earlier.
552 ;; `run-hooks' was a lisp function in Emacs 19.29 and earlier.
553 ;; So, in Emacs 19.29, `run-hooks' and others will be overrided.
554 ;; But, who cares it?
555 (static-unless (subrp (symbol-function 'run-hooks))
556 (require 'localhook))
558 ;; Emacs 19.29/XEmacs 19.14(?) and later: (add-to-list LIST-VAR ELEMENT)
559 (defun-maybe add-to-list (list-var element)
560 "Add to the value of LIST-VAR the element ELEMENT if it isn't there yet.
561 The test for presence of ELEMENT is done with `equal'.
562 If you want to use `add-to-list' on a variable that is not defined
563 until a certain package is loaded, you should put the call to `add-to-list'
564 into a hook function that will be run only after loading the package.
565 `eval-after-load' provides one way to do this. In some cases
566 other hooks, such as major mode hooks, can do the job."
567 (or (member element (symbol-value list-var))
568 (set list-var (cons element (symbol-value list-var)))))
570 ;; (eval-after-load FILE FORM)
571 ;; Emacs 19.28 and earlier do not evaluate FORM if FILE is already loaded.
572 ;; XEmacs 20.2 and earlier have `after-load-alist', but refuse to support
573 ;; `eval-after-load'. (see comments in XEmacs/lisp/subr.el.)
576 ;; for XEmacs 20.2 and earlier.
577 (defun-maybe eval-after-load (file form)
578 "Arrange that, if FILE is ever loaded, FORM will be run at that time.
579 This makes or adds to an entry on `after-load-alist'.
580 If FILE is already loaded, evaluate FORM right now.
581 It does nothing if FORM is already on the list for FILE.
582 FILE should be the name of a library, with no directory name."
583 ;; Make sure there is an element for FILE.
584 (or (assoc file after-load-alist)
585 (setq after-load-alist (cons (list file) after-load-alist)))
586 ;; Add FORM to the element if it isn't there.
587 (let ((elt (assoc file after-load-alist)))
588 (or (member form (cdr elt))
590 (nconc elt (list form))
591 ;; If the file has been loaded already, run FORM right away.
592 (and (assoc file load-history)
595 ((>= emacs-major-version 20))
596 ((and (= emacs-major-version 19)
597 (< emacs-minor-version 29))
598 ;; for Emacs 19.28 and earlier.
599 (defun eval-after-load (file form)
600 "Arrange that, if FILE is ever loaded, FORM will be run at that time.
601 This makes or adds to an entry on `after-load-alist'.
602 If FILE is already loaded, evaluate FORM right now.
603 It does nothing if FORM is already on the list for FILE.
604 FILE should be the name of a library, with no directory name."
605 ;; Make sure there is an element for FILE.
606 (or (assoc file after-load-alist)
607 (setq after-load-alist (cons (list file) after-load-alist)))
608 ;; Add FORM to the element if it isn't there.
609 (let ((elt (assoc file after-load-alist)))
610 (or (member form (cdr elt))
612 (nconc elt (list form))
613 ;; If the file has been loaded already, run FORM right away.
614 (and (assoc file load-history)
618 ;; should emulate for v18?
621 (defun-maybe eval-next-after-load (file)
622 "Read the following input sexp, and run it whenever FILE is loaded.
623 This makes or adds to an entry on `after-load-alist'.
624 FILE should be the name of a library, with no directory name."
625 (eval-after-load file (read)))
627 ;;; @@ Input and display facilities.
629 ;; XXX: (defun read-passwd (prompt &optional confirm default))
633 ;; Avoid compiler warnings about this variable,
634 ;; which has a special meaning on certain system types.
635 (defvar-maybe buffer-file-type nil
636 "Non-nil if the visited file is a binary file.
637 This variable is meaningful on MS-DOG and Windows NT.
638 On those systems, it is automatically local in every buffer.
639 On other systems, this variable is normally always nil.")
641 ;; Emacs 20.1/XEmacs 20.3(?) and later: (save-current-buffer &rest BODY)
642 ;; v20 defines `save-current-buffer' as a C primitive (in src/editfns.c)
643 ;; and introduces a new bytecode Bsave_current_buffer(_1), replacing an
644 ;; obsolete bytecode Bread_char.
645 ;; This is a source of incompatibility of .elc between v18/v19 and v20.
646 ;; (XEmacs compiler takes care of it if compatibility mode is enabled.)
647 (defmacro-maybe save-current-buffer (&rest body)
648 "Save the current buffer; execute BODY; restore the current buffer.
649 Executes BODY just like `progn'."
650 (` (let ((orig-buffer (current-buffer)))
653 (if (buffer-live-p orig-buffer)
654 (set-buffer orig-buffer))))))
656 ;; Emacs 20.1/XEmacs 20.3(?) and later: (with-current-buffer BUFFER &rest BODY)
657 (defmacro-maybe with-current-buffer (buffer &rest body)
658 "Execute the forms in BODY with BUFFER as the current buffer.
659 The value returned is the value of the last form in BODY.
660 See also `with-temp-buffer'."
661 (` (save-current-buffer
662 (set-buffer (, buffer))
665 ;; Emacs 20.1/XEmacs 20.3(?) and later: (with-temp-file FILE &rest FORMS)
666 (defmacro-maybe with-temp-file (file &rest forms)
667 "Create a new buffer, evaluate FORMS there, and write the buffer to FILE.
668 The value of the last form in FORMS is returned, like `progn'.
669 See also `with-temp-buffer'."
670 (let ((temp-file (make-symbol "temp-file"))
671 (temp-buffer (make-symbol "temp-buffer")))
672 (` (let (((, temp-file) (, file))
674 (get-buffer-create (generate-new-buffer-name " *temp file*"))))
677 (with-current-buffer (, temp-buffer)
679 (with-current-buffer (, temp-buffer)
681 (write-region (point-min) (point-max) (, temp-file) nil 0)))
682 (and (buffer-name (, temp-buffer))
683 (kill-buffer (, temp-buffer))))))))
685 ;; Emacs 20.4 and later: (with-temp-message MESSAGE &rest BODY)
686 ;; This macro uses `current-message', which appears in v20.
687 (static-when (and (fboundp 'current-message)
688 (subrp (symbol-function 'current-message)))
689 (defmacro-maybe with-temp-message (message &rest body)
691 Display MESSAGE temporarily if non-nil while BODY is evaluated.
692 The original message is restored to the echo area after BODY has finished.
693 The value returned is the value of the last form in BODY.
694 MESSAGE is written to the message log buffer if `message-log-max' is non-nil.
695 If MESSAGE is nil, the echo area and message log buffer are unchanged.
696 Use a MESSAGE of \"\" to temporarily clear the echo area."
697 (let ((current-message (make-symbol "current-message"))
698 (temp-message (make-symbol "with-temp-message")))
699 (` (let (((, temp-message) (, message))
700 ((, current-message)))
703 (when (, temp-message)
704 (setq (, current-message) (current-message))
705 (message "%s" (, temp-message))
707 (and (, temp-message) (, current-message)
708 (message "%s" (, current-message))))))))))
710 ;; Emacs 20.1/XEmacs 20.3(?) and later: (with-temp-buffer &rest FORMS)
711 (defmacro-maybe with-temp-buffer (&rest forms)
712 "Create a temporary buffer, and evaluate FORMS there like `progn'.
713 See also `with-temp-file' and `with-output-to-string'."
714 (let ((temp-buffer (make-symbol "temp-buffer")))
715 (` (let (((, temp-buffer)
716 (get-buffer-create (generate-new-buffer-name " *temp*"))))
718 (with-current-buffer (, temp-buffer)
720 (and (buffer-name (, temp-buffer))
721 (kill-buffer (, temp-buffer))))))))
723 ;; Emacs 20.1/XEmacs 20.3(?) and later: (with-output-to-string &rest BODY)
724 (defmacro-maybe with-output-to-string (&rest body)
725 "Execute BODY, return the text it sent to `standard-output', as a string."
726 (` (let ((standard-output
727 (get-buffer-create (generate-new-buffer-name " *string-output*"))))
728 (let ((standard-output standard-output))
730 (with-current-buffer standard-output
733 (kill-buffer nil))))))
735 ;; Emacs 20.1 and later: (combine-after-change-calls &rest BODY)
736 (defmacro-maybe combine-after-change-calls (&rest body)
737 "Execute BODY, but don't call the after-change functions till the end.
738 If BODY makes changes in the buffer, they are recorded
739 and the functions on `after-change-functions' are called several times
740 when BODY is finished.
741 The return value is the value of the last form in BODY.
743 If `before-change-functions' is non-nil, then calls to the after-change
744 functions can't be deferred, so in that case this macro has no effect.
746 Do not alter `after-change-functions' or `before-change-functions'
749 This emulating macro does not support after-change functions at all,
753 ;; Emacs 19.29/XEmacs 19.14(?) and later: (match-string NUM &optional STRING)
754 (defun-maybe match-string (num &optional string)
755 "Return string of text matched by last search.
756 NUM specifies which parenthesized expression in the last regexp.
757 Value is nil if NUMth pair didn't match, or there were less than NUM pairs.
758 Zero means the entire text matched by the whole regexp or whole string.
759 STRING should be given if the last search was by `string-match' on STRING."
760 (if (match-beginning num)
762 (substring string (match-beginning num) (match-end num))
763 (buffer-substring (match-beginning num) (match-end num)))))
765 ;; Emacs 20.3 and later: (match-string-no-properties NUM &optional STRING)
766 (defun-maybe match-string-no-properties (num &optional string)
767 "Return string of text matched by last search, without text properties.
768 NUM specifies which parenthesized expression in the last regexp.
769 Value is nil if NUMth pair didn't match, or there were less than NUM pairs.
770 Zero means the entire text matched by the whole regexp or whole string.
771 STRING should be given if the last search was by `string-match' on STRING."
772 (if (match-beginning num)
775 (substring string (match-beginning num) (match-end num))))
776 (set-text-properties 0 (length result) nil result)
778 (buffer-substring-no-properties (match-beginning num)
781 ;; Emacs 20.1/XEmacs 20.3(?) and later: (split-string STRING &optional PATTERN)
782 ;; Here is a XEmacs version.
783 (defun-maybe split-string (string &optional pattern)
784 "Return a list of substrings of STRING which are separated by PATTERN.
785 If PATTERN is omitted, it defaults to \"[ \\f\\t\\n\\r\\v]+\"."
787 (setq pattern "[ \f\t\n\r\v]+"))
788 ;; The FSF version of this function takes care not to cons in case
789 ;; of infloop. Maybe we should synch?
790 (let (parts (start 0))
791 (while (string-match pattern string start)
792 (setq parts (cons (substring string start (match-beginning 0)) parts)
793 start (match-end 0)))
794 (nreverse (cons (substring string start) parts))))
796 ;; Emacs 20.1/XEmacs 20.3 (but first appeared in Epoch?): (functionp OBJECT)
797 (defun-maybe functionp (object)
798 "Non-nil if OBJECT is a type of object that can be called as a function."
799 (or (subrp object) (byte-code-function-p object)
800 (eq (car-safe object) 'lambda)
801 (and (symbolp object) (fboundp object))))
804 ;;; @ Window commands emulation. (lisp/window.el)
807 (defmacro-maybe save-selected-window (&rest body)
808 "Execute BODY, then select the window that was selected before BODY."
810 '((save-selected-window-window (selected-window)))
811 (list 'unwind-protect
813 (list 'select-window 'save-selected-window-window))))
816 ;;; @ Basic editing commands emulation. (lisp/simple.el)
820 ;;; @ File input and output commands emulation. (lisp/files.el)
823 (defvar-maybe temporary-file-directory
824 (file-name-as-directory
825 (cond ((memq system-type '(ms-dos windows-nt))
826 (or (getenv "TEMP") (getenv "TMPDIR") (getenv "TMP") "c:/temp"))
827 ((memq system-type '(vax-vms axp-vms))
828 (or (getenv "TMPDIR") (getenv "TMP") (getenv "TEMP") "SYS$SCRATCH:"))
830 (or (getenv "TMPDIR") (getenv "TMP") (getenv "TEMP") "/tmp"))))
831 "The directory for writing temporary files.")
833 ;; Actually, `path-separator' is defined in src/emacs.c and overrided
835 (defvar-maybe path-separator ":"
836 "The directory separator in search paths, as a string.")
838 ;; `convert-standard-filename' is defined in lisp/files.el and overrided
839 ;; in lisp/dos-fns.el and lisp/w32-fns.el for each environment.
841 ;; must be load-time check to share .elc between different systems.
842 ((fboundp 'convert-standard-filename))
843 ((memq system-type '(windows-nt ms-dos))
844 ;; should we do (require 'filename) at load-time ?
845 ;; (require 'filename)
846 ;; filename.el requires many modules, so we do not want to load at
847 ;; compile-time. instead, suppress warnings by this.
849 (autoload 'filename-maybe-truncate-by-size "filename")
850 (autoload 'filename-special-filter "filename"))
851 (defun convert-standard-filename (filename)
852 "Convert a standard file's name to something suitable for the current OS.
853 This function's standard definition is trivial; it just returns the argument.
854 However, on some systems, the function is redefined
855 with a definition that really does change some file names.
856 Under `windows-nt' or `ms-dos', it refers `filename-replacement-alist' and
857 `filename-limit-length' for the basic filename and each parent directory name."
859 (let* ((names (split-string filename "/"))
860 (drive-name (car names))
863 (filename-maybe-truncate-by-size
864 (filename-special-filter string))))))
866 ((eq 1 (length names))
867 (funcall filter drive-name))
868 ((string-match "^[^/]:$" drive-name)
869 (concat drive-name "/" (mapconcat filter (cdr names) "/")))
871 (mapconcat filter names "/"))))))
873 (defun convert-standard-filename (filename)
874 "Convert a standard file's name to something suitable for the current OS.
875 This function's standard definition is trivial; it just returns the argument.
876 However, on some systems, the function is redefined
877 with a definition that really does change some file names.
878 Under `windows-nt' or `ms-dos', it refers `filename-replacement-alist' and
879 `filename-limit-length' for the basic filename and each parent directory name."
883 ((fboundp 'insert-file-contents-literally))
884 ((boundp 'file-name-handler-alist)
885 ;; Use `defun-maybe' to update `load-history'.
886 (defun-maybe insert-file-contents-literally (filename &optional visit
888 "Like `insert-file-contents', q.v., but only reads in the file.
889 A buffer may be modified in several ways after reading into the buffer due
890 to advanced Emacs features, such as file-name-handlers, format decoding,
891 find-file-hooks, etc.
892 This function ensures that none of these modifications will take place."
893 (let (file-name-handler-alist)
894 (insert-file-contents filename visit beg end replace))))
896 (defalias 'insert-file-contents-literally 'insert-file-contents)))
898 (defun-maybe file-name-sans-extension (filename)
899 "Return FILENAME sans final \"extension\".
900 The extension, in a file name, is the part that follows the last `.'."
902 (let ((file (file-name-sans-versions (file-name-nondirectory filename)))
904 (if (string-match "\\.[^.]*\\'" file)
905 (if (setq directory (file-name-directory filename))
906 (expand-file-name (substring file 0 (match-beginning 0))
908 (substring file 0 (match-beginning 0)))
912 ;;; @ XEmacs emulation.
915 (defun-maybe find-face (face-or-name)
916 "Retrieve the face of the given name.
917 If FACE-OR-NAME is a face object, it is simply returned.
918 Otherwise, FACE-OR-NAME should be a symbol. If there is no such face,
919 nil is returned. Otherwise the associated face object is returned."
920 (car (memq face-or-name (face-list))))
922 ;; Emacs 20.5 defines this as an alias for `line-beginning-position'.
923 ;; Therefore, optional 2nd arg BUFFER is not portable.
924 (defun-maybe point-at-bol (&optional n buffer)
925 "Return the character position of the first character on the current line.
926 With argument N not nil or 1, move forward N - 1 lines first.
927 If scan reaches end of buffer, return that position.
928 This function does not move point."
930 (if buffer (set-buffer buffer))
931 (forward-line (1- (or n 1)))
934 ;; Emacs 20.5 defines this as an alias for `line-end-position'.
935 ;; Therefore, optional 2nd arg BUFFER is not portable.
936 (defun-maybe point-at-eol (&optional n buffer)
937 "Return the character position of the last character on the current line.
938 With argument N not nil or 1, move forward N - 1 lines first.
939 If scan reaches end of buffer, return that position.
940 This function does not move point."
942 (if buffer (set-buffer buffer))
943 (end-of-line (or n 1))
946 (defsubst-maybe define-obsolete-function-alias (oldfun newfun)
947 "Define OLDFUN as an obsolete alias for function NEWFUN.
948 This makes calling OLDFUN equivalent to calling NEWFUN and marks OLDFUN
950 (defalias oldfun newfun)
951 (make-obsolete oldfun newfun))
953 ;; XEmacs 21: (character-to-event CH &optional EVENT DEVICE)
954 (defun-maybe character-to-event (ch)
955 "Convert keystroke CH into an event structure, replete with bucky bits.
956 Note that CH (the keystroke specifier) can be an integer, a character
957 or a symbol such as 'clear."
960 ;; XEmacs 21: (event-to-character EVENT
961 ;; &optional ALLOW-EXTRA-MODIFIERS ALLOW-META ALLOW-NON-ASCII)
962 (defun-maybe-cond event-to-character (event)
963 "Return the character approximation to the given event object.
964 If the event isn't a keypress, this returns nil."
965 ((and (fboundp 'read-event)
966 (subrp (symbol-function 'read-event)))
967 ;; Emacs 19 and later.
970 ;; mask is (BASE-TYPE MODIFIER-BITS) or nil.
971 (let ((mask (get event 'event-symbol-element-mask)))
973 (let ((base (get (car mask) 'ascii-character)))
975 (logior base (car (cdr mask))))))))
976 ((integerp event) event)))
978 ;; v18. Is this correct?
981 ;; v18: no event; (read-char)
982 ;; Emacs 19, 20.1 and 20.2: (read-event)
983 ;; Emacs 20.3: (read-event &optional PROMPT SUPPRESS-INPUT-METHOD)
984 ;; Emacs 20.4: (read-event &optional PROMPT INHERIT-INPUT-METHOD)
985 ;; XEmacs: (next-event &optional EVENT PROMPT),
986 ;; (next-command-event &optional EVENT PROMPT)
987 (defun-maybe-cond next-command-event (&optional event prompt)
988 "Read an event object from the input stream.
989 If EVENT is non-nil, it should be an event object and will be filled
990 in and returned; otherwise a new event object will be created and
992 If PROMPT is non-nil, it should be a string and will be displayed in
993 the echo area while this function is waiting for an event."
994 ((and (>= emacs-major-version 20)
995 (>= emacs-minor-version 4))
996 ;; Emacs 20.4 and later.
997 (read-event prompt)) ; should specify 2nd arg?
998 ((and (= emacs-major-version 20)
999 (= emacs-minor-version 3))
1001 (read-event prompt)) ; should specify 2nd arg?
1002 ((and (fboundp 'read-event)
1003 (subrp (symbol-function 'read-event)))
1004 ;; Emacs 19, 20.1 and 20.2.
1005 (if prompt (message prompt))
1008 (if prompt (message prompt))
1012 ;;; @ MULE 2 emulation.
1015 (defun-maybe-cond cancel-undo-boundary ()
1016 "Cancel undo boundary."
1017 ((boundp 'buffer-undo-list)
1018 ;; for Emacs 19 and later.
1019 (if (and (consp buffer-undo-list)
1020 (null (car buffer-undo-list)))
1021 (setq buffer-undo-list (cdr buffer-undo-list)))))
1027 ;;; poe.el ends here