1 ;;; poe.el --- Portable Outfit for Emacsen; -*-byte-compile-dynamic: t;-*-
3 ;; Copyright (C) 1995,1996,1997,1998,1999 Free Software Foundation, Inc.
5 ;; Author: MORIOKA Tomohiko <tomo@m17n.org>
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 ;; This modules does not includes MULE related features.
28 ;; MULE related features are supported by `poem'.
34 (or (boundp 'current-load-list) (setq current-load-list nil))
36 (put 'defun-maybe 'lisp-indent-function 'defun)
37 (defmacro defun-maybe (name &rest everything-else)
38 "Define NAME as a function if NAME is not defined.
39 See also the function `defun'."
40 (or (and (fboundp name)
41 (not (get name 'defun-maybe)))
42 (` (or (fboundp (quote (, name)))
44 (defun (, name) (,@ everything-else))
45 ;; This `defun' will be compiled to `fset', which does
46 ;; not update `load-history'.
47 (setq current-load-list
48 (cons (quote (, name)) current-load-list))
49 (put (quote (, name)) 'defun-maybe t))))))
51 (put 'defmacro-maybe 'lisp-indent-function 'defun)
52 (defmacro defmacro-maybe (name &rest everything-else)
53 "Define NAME as a macro if NAME is not defined.
54 See also the function `defmacro'."
55 (or (and (fboundp name)
56 (not (get name 'defmacro-maybe)))
57 (` (or (fboundp (quote (, name)))
59 (defmacro (, name) (,@ everything-else))
60 (setq current-load-list
61 (cons (quote (, name)) current-load-list))
62 (put (quote (, name)) 'defmacro-maybe t))))))
64 (put 'defsubst-maybe 'lisp-indent-function 'defun)
65 (defmacro defsubst-maybe (name &rest everything-else)
66 "Define NAME as an inline function if NAME is not defined.
67 See also the macro `defsubst'."
68 (or (and (fboundp name)
69 (not (get name 'defsubst-maybe)))
70 (` (or (fboundp (quote (, name)))
72 (defsubst (, name) (,@ everything-else))
73 (setq current-load-list
74 (cons (quote (, name)) current-load-list))
75 (put (quote (, name)) 'defsubst-maybe t))))))
77 (defmacro defalias-maybe (symbol definition)
78 "Define SYMBOL as an alias for DEFINITION if SYMBOL is not defined.
79 See also the function `defalias'."
80 (setq symbol (eval symbol))
81 (or (and (fboundp symbol)
82 (not (get symbol 'defalias-maybe)))
83 (` (or (fboundp (quote (, symbol)))
85 (defalias (quote (, symbol)) (, definition))
86 (setq current-load-list
87 (cons (quote (, symbol)) current-load-list))
88 (put (quote (, symbol)) 'defalias-maybe t))))))
90 (defmacro defvar-maybe (name &rest everything-else)
91 "Define NAME as a variable if NAME is not defined.
92 See also the function `defvar'."
93 (or (and (boundp name)
94 (not (get name 'defvar-maybe)))
95 (` (or (boundp (quote (, name)))
97 (defvar (, name) (,@ everything-else))
98 ;; byte-compiler will generate code to update
100 (put (quote (, name)) 'defvar-maybe t))))))
102 (defmacro defconst-maybe (name &rest everything-else)
103 "Define NAME as a constant variable if NAME is not defined.
104 See also the function `defconst'."
105 (or (and (boundp name)
106 (not (get name 'defconst-maybe)))
107 (` (or (boundp (quote (, name)))
109 (defconst (, name) (,@ everything-else))
110 ;; byte-compiler will generate code to update
112 (put (quote (, name)) 'defconst-maybe t))))))
114 (defmacro defun-maybe-cond (name args &optional doc &rest everything-else)
116 (setq everything-else (cons doc everything-else)
118 (or (and (fboundp name)
119 (not (get name 'defun-maybe)))
120 (` (or (fboundp (quote (, name)))
128 (` (defun (, name) (, args)
131 (` (defun (, name) (, args)
132 (,@ (cdr case))))))))
134 (setq current-load-list
135 (cons (quote (, name)) current-load-list))
136 (put (quote (, name)) 'defun-maybe t))))))
138 (defmacro defmacro-maybe-cond (name args &optional doc &rest everything-else)
140 (setq everything-else (cons doc everything-else)
142 (or (and (fboundp name)
143 (not (get name 'defmacro-maybe)))
144 (` (or (fboundp (quote (, name)))
152 (` (defmacro (, name) (, args)
155 (` (defmacro (, name) (, args)
156 (,@ (cdr case))))))))
158 (setq current-load-list
159 (cons (quote (, name)) current-load-list))
160 (put (quote (, name)) 'defmacro-maybe t))))))
162 (defun subr-fboundp (symbol)
163 "Return t if SYMBOL's function definition is a built-in function."
164 (and (fboundp symbol)
165 (subrp (symbol-function symbol))))
167 (defconst-maybe emacs-major-version (string-to-int emacs-version))
168 (defconst-maybe emacs-minor-version
170 (substring emacs-version
171 (string-match (format "%d\\." emacs-major-version)
174 (cond ((featurep 'xemacs)
175 (require 'poe-xemacs)
177 ((string-match "XEmacs" emacs-version)
179 (require 'poe-xemacs)
181 ((> emacs-major-version 20))
182 ((= emacs-major-version 20)
183 (cond ((subr-fboundp 'string)
184 ;; Emacs 20.3 or later
186 ((subr-fboundp 'concat-chars)
187 ;; Emacs 20.1 or later
188 (defalias 'string 'concat-chars)
191 ((= emacs-major-version 19)
192 ;; XXX: should do compile-time and load-time check before loading
193 ;; "localhook". But, it is difficult since "localhook" is
194 ;; already loaded via "install" at compile-time. any idea?
195 (if (< emacs-minor-version 29)
196 (require 'localhook)))
199 ;; XXX: should do compile-time and load-time check before loading
200 ;; "localhook". But, it is difficult since "localhook" is
201 ;; already loaded via "install" at compile-time. any idea?
202 (require 'localhook)))
204 ;;; `eval-when-compile' is defined in "poe-18" under v18 with old compiler.
205 (eval-when-compile (require 'static))
207 ;; imported from emacs-20.3/lisp/emacs-lisp/edebug.el.
208 ;; `def-edebug-spec' is an autoloaded macro in v19 and later.
209 (defmacro-maybe def-edebug-spec (symbol spec)
210 "Set the edebug-form-spec property of SYMBOL according to SPEC.
211 Both SYMBOL and SPEC are unevaluated. The SPEC can be 0, t, a symbol
212 \(naming a function\), or a list."
213 (` (put (quote (, symbol)) 'edebug-form-spec (quote (, spec)))))
215 (def-edebug-spec defun-maybe defun)
216 (def-edebug-spec defmacro-maybe defmacro)
217 (def-edebug-spec defsubst-maybe defun)
218 (def-edebug-spec defun-maybe-cond
219 (&define name lambda-list
221 [&rest ([¬ eval] [&rest sexp])]
222 [&optional (eval [&optional ("interactive" interactive)] def-body)]
224 (def-edebug-spec defmacro-maybe-cond
225 (&define name lambda-list
226 [&rest ([¬ eval] [&rest sexp])]
227 [&optional (eval def-body)]
230 ;;; Emacs 20.1 emulation
232 ;; imported from emacs-20.3/lisp/subr.el.
233 (defmacro-maybe when (cond &rest body)
234 "If COND yields non-nil, do BODY, else return nil."
235 (list 'if cond (cons 'progn body)))
236 ;; (def-edebug-spec when (&rest form))
238 ;; imported from emacs-20.3/lisp/subr.el.
239 (defmacro-maybe unless (cond &rest body)
240 "If COND yields nil, do BODY, else return nil."
241 (cons 'if (cons cond (cons nil body))))
242 ;; (def-edebug-spec unless (&rest form))
245 ;;; @ Emacs 19.23 emulation
248 (defun-maybe minibuffer-prompt-width ()
249 "Return the display width of the minibuffer prompt."
251 (set-buffer (window-buffer (minibuffer-window)))
255 ;;; @ Emacs 19.29 emulation
258 (defvar-maybe path-separator ":"
259 "The directory separator in search paths, as a string.")
261 (defun-maybe buffer-substring-no-properties (start end)
262 "Return the characters of part of the buffer, without the text properties.
263 The two arguments START and END are character positions;
264 they can be in either order.
265 \[Emacs 19.29 emulating function]"
266 (let ((string (buffer-substring start end)))
267 (set-text-properties 0 (length string) nil string)
270 ;; imported from emacs-19.34/lisp/subr.el.
271 (defun-maybe match-string (num &optional string)
272 "Return string of text matched by last search.
273 NUM specifies which parenthesized expression in the last regexp.
274 Value is nil if NUMth pair didn't match, or there were less than NUM pairs.
275 Zero means the entire text matched by the whole regexp or whole string.
276 STRING should be given if the last search was by `string-match' on STRING.
277 \[Emacs 19.29 emulating function]"
278 (if (match-beginning num)
280 (substring string (match-beginning num) (match-end num))
281 (buffer-substring (match-beginning num) (match-end num)))))
283 (static-unless (or (featurep 'xemacs)
284 (>= emacs-major-version 20)
285 (and (= emacs-major-version 19)
286 (>= emacs-minor-version 29)))
287 ;; for Emacs 19.28 or earlier
288 (unless (fboundp 'si:read-string)
289 (fset 'si:read-string (symbol-function 'read-string))
290 (defun read-string (prompt &optional initial-input history)
291 "Read a string from the minibuffer, prompting with string PROMPT.
292 If non-nil, second arg INITIAL-INPUT is a string to insert before reading.
293 The third arg HISTORY, is dummy for compatibility.
294 See `read-from-minibuffer' for details of HISTORY argument."
295 (si:read-string prompt initial-input))
298 (defun-maybe rassoc (key list)
299 "Return non-nil if KEY is `equal' to the cdr of an element of LIST.
300 The value is actually the element of LIST whose cdr equals KEY.
301 Elements of LIST that are not conses are ignored.
302 \[Emacs 19.29 emulating function]"
305 (cond ((not (consp (car list))))
306 ((equal (cdr (car list)) key)
307 (throw 'found (car list)) ))
308 (setq list (cdr list)) )))
310 ;; imported from emacs-19.34/lisp/files.el.
311 (defun-maybe file-name-sans-extension (filename)
312 "Return FILENAME sans final \"extension\".
313 The extension, in a file name, is the part that follows the last `.'.
314 \[Emacs 19.29 emulating function]"
316 (let ((file (file-name-sans-versions (file-name-nondirectory filename)))
318 (if (string-match "\\.[^.]*\\'" file)
319 (if (setq directory (file-name-directory filename))
320 (expand-file-name (substring file 0 (match-beginning 0))
322 (substring file 0 (match-beginning 0)))
326 ;;; @ Emacs 19.30 emulation
329 ;; imported from emacs-19.34/lisp/subr.el.
330 (defun-maybe add-to-list (list-var element)
331 "Add to the value of LIST-VAR the element ELEMENT if it isn't there yet.
332 The test for presence of ELEMENT is done with `equal'.
333 If you want to use `add-to-list' on a variable that is not defined
334 until a certain package is loaded, you should put the call to `add-to-list'
335 into a hook function that will be run only after loading the package.
336 `eval-after-load' provides one way to do this. In some cases
337 other hooks, such as major mode hooks, can do the job.
338 \[Emacs 19.30 emulating function]"
339 (or (member element (symbol-value list-var))
340 (set list-var (cons element (symbol-value list-var)))))
342 (cond ((fboundp 'insert-file-contents-literally))
343 ((boundp 'file-name-handler-alist)
344 (defun insert-file-contents-literally
345 (filename &optional visit beg end replace)
346 "Like `insert-file-contents', q.v., but only reads in the file.
347 A buffer may be modified in several ways after reading into the buffer due
348 to advanced Emacs features, such as file-name-handlers, format decoding,
349 find-file-hooks, etc.
350 This function ensures that none of these modifications will take place.
351 \[Emacs 19.30 emulating function]"
352 (let (file-name-handler-alist)
353 (insert-file-contents filename visit beg end replace)))
356 (defalias 'insert-file-contents-literally 'insert-file-contents)
360 ;;; @ Emacs 19.31 emulation
363 (defun-maybe buffer-live-p (object)
364 "Return non-nil if OBJECT is a buffer which has not been killed.
365 Value is nil if OBJECT is not a buffer or if it has been killed.
366 \[Emacs 19.31 emulating function]"
369 (buffer-name (get-buffer object))
372 ;; imported from emacs-19.34/lisp/window.el.
373 (defmacro-maybe save-selected-window (&rest body)
374 "Execute BODY, then select the window that was selected before BODY.
375 \[Emacs 19.31 emulating function]"
377 '((save-selected-window-window (selected-window)))
378 (list 'unwind-protect
380 (list 'select-window 'save-selected-window-window))))
382 (defun-maybe-cond convert-standard-filename (filename)
383 "Convert a standard file's name to something suitable for the current OS.
384 This function's standard definition is trivial; it just returns the argument.
385 However, on some systems, the function is redefined
386 with a definition that really does change some file names.
387 Under `windows-nt' or `ms-dos', it refers `filename-replacement-alist' and
388 `filename-limit-length' for the basic filename and each parent directory name.
389 \[Emacs 19.31 emulating function]"
390 ((memq system-type '(windows-nt ms-dos))
392 (let* ((names (split-string filename "/"))
393 (drive-name (car names))
394 (filter (function (lambda (string)
395 (filename-maybe-truncate-by-size
396 (filename-special-filter string))))))
397 (cond ((eq 1 (length names))
398 (funcall filter drive-name))
399 ((string-match "^[^/]:$" drive-name)
400 (concat drive-name "/" (mapconcat filter (cdr names) "/")))
401 (t (mapconcat filter names "/")))))
405 ;;; @ Emacs 20.1 emulation
408 ;; imported from emacs-20.3/lisp/subr.el.
409 (defsubst-maybe caar (x)
410 "Return the car of the car of X."
413 ;; imported from emacs-20.3/lisp/subr.el.
414 (defsubst-maybe cadr (x)
415 "Return the car of the cdr of X."
418 ;; imported from emacs-20.3/lisp/subr.el.
419 (defsubst-maybe cdar (x)
420 "Return the cdr of the car of X."
423 ;; imported from emacs-20.3/lisp/subr.el.
424 (defsubst-maybe cddr (x)
425 "Return the cdr of the cdr of X."
428 ;; imported from emacs-20.3/lisp/subr.el.
429 (defun-maybe last (x &optional n)
430 "Return the last link of the list X. Its car is the last element.
431 If X is nil, return nil.
432 If N is non-nil, return the Nth-to-last link of X.
433 If N is bigger than the length of X, return X."
437 (setq m (1+ m) p (cdr p)))
439 (if (< n m) (nthcdr (- m n) x) x)))
444 ;; In Emacs 20.3, save-current-buffer is defined in src/editfns.c.
445 (defmacro-maybe save-current-buffer (&rest body)
446 "Save the current buffer; execute BODY; restore the current buffer.
447 Executes BODY just like `progn'."
448 (` (let ((orig-buffer (current-buffer)))
451 (if (buffer-live-p orig-buffer)
452 (set-buffer orig-buffer))))))
454 ;; imported from emacs-20.3/lisp/subr.el. (with macro style change)
455 (defmacro-maybe with-current-buffer (buffer &rest body)
456 "Execute the forms in BODY with BUFFER as the current buffer.
457 The value returned is the value of the last form in BODY.
458 See also `with-temp-buffer'."
459 (` (save-current-buffer
460 (set-buffer (, buffer))
463 ;; imported from emacs-20.3/lisp/subr.el. (with macro style change)
464 (defmacro-maybe with-temp-file (file &rest forms)
465 "Create a new buffer, evaluate FORMS there, and write the buffer to FILE.
466 The value of the last form in FORMS is returned, like `progn'.
467 See also `with-temp-buffer'."
468 (let ((temp-file (make-symbol "temp-file"))
469 (temp-buffer (make-symbol "temp-buffer")))
470 (` (let (((, temp-file) (, file))
472 (get-buffer-create (generate-new-buffer-name " *temp file*"))))
475 (with-current-buffer (, temp-buffer)
477 (with-current-buffer (, temp-buffer)
479 (write-region (point-min) (point-max) (, temp-file) nil 0)))
480 (and (buffer-name (, temp-buffer))
481 (kill-buffer (, temp-buffer))))))))
483 ;; imported from emacs-20.3/lisp/subr.el. (with macro style change)
484 (defmacro-maybe with-temp-buffer (&rest forms)
485 "Create a temporary buffer, and evaluate FORMS there like `progn'.
486 See also `with-temp-file' and `with-output-to-string'."
487 (let ((temp-buffer (make-symbol "temp-buffer")))
488 (` (let (((, temp-buffer)
489 (get-buffer-create (generate-new-buffer-name " *temp*"))))
491 (with-current-buffer (, temp-buffer)
493 (and (buffer-name (, temp-buffer))
494 (kill-buffer (, temp-buffer))))))))
496 (defmacro-maybe combine-after-change-calls (&rest body)
500 ;; imported from emacs-20.3/lisp/subr.el.
501 (defun-maybe functionp (object)
502 "Non-nil if OBJECT is a type of object that can be called as a function."
503 (or (subrp object) (byte-code-function-p object)
504 (eq (car-safe object) 'lambda)
505 (and (symbolp object) (fboundp object))))
507 ;; imported from emacs-20.3/lisp/emacs-lisp/cl.el.
508 (defun-maybe butlast (x &optional n)
509 "Returns a copy of LIST with the last N elements removed."
510 (if (and n (<= n 0)) x
511 (nbutlast (copy-sequence x) n)))
513 ;; imported from emacs-20.3/lisp/emacs-lisp/cl.el.
514 (defun-maybe nbutlast (x &optional n)
515 "Modifies LIST to remove the last N elements."
516 (let ((m (length x)))
520 (if (> n 0) (setcdr (nthcdr (- (1- m) n) x) nil))
523 ;; imported from XEmacs 21.
524 (defun-maybe split-string (string &optional pattern)
525 "Return a list of substrings of STRING which are separated by PATTERN.
526 If PATTERN is omitted, it defaults to \"[ \\f\\t\\n\\r\\v]+\"."
528 (setq pattern "[ \f\t\n\r\v]+"))
529 ;; The FSF version of this function takes care not to cons in case
530 ;; of infloop. Maybe we should synch?
531 (let (parts (start 0))
532 (while (string-match pattern string start)
533 (setq parts (cons (substring string start (match-beginning 0)) parts)
534 start (match-end 0)))
535 (nreverse (cons (substring string start) parts))))
537 ;; emulating char-before of Emacs 20.
538 (static-condition-case nil
539 ;; compile-time check.
541 ;; XXX: this file is already loaded at compile-time,
542 ;; so this test will always success.
544 ;; If our definition is found at compile-time, signal an error.
545 ;; XXX: should signal more specific error.
546 (if (get 'char-before 'defun-maybe)
548 (wrong-number-of-arguments ; Mule 1.*, 2.*.
550 (or (fboundp 'si:char-before)
552 (fset 'si:char-before (symbol-function 'char-before))
553 (put 'char-before 'defun-maybe t)
554 ;; takes IGNORED for backward compatibility.
555 (defun char-before (&optional pos ignored)
557 Return character in current buffer preceding position POS.
558 POS is an integer or a buffer pointer.
559 If POS is out of range, the value is nil."
560 (si:char-before (or pos (point)))))))
561 (void-function ; non-Mule.
563 (defun-maybe char-before (&optional pos)
565 Return character in current buffer preceding position POS.
566 POS is an integer or a buffer pointer.
567 If POS is out of range, the value is nil."
570 (and (= (goto-char pos) (point))
575 (error ; found our definition at compile-time.
579 (wrong-number-of-arguments ; Mule 1.*, 2.*.
580 (or (fboundp 'si:char-before)
582 (fset 'si:char-before (symbol-function 'char-before))
583 (put 'char-before 'defun-maybe t)
584 ;; takes IGNORED for backward compatibility.
585 (defun char-before (&optional pos ignored)
587 Return character in current buffer preceding position POS.
588 POS is an integer or a buffer pointer.
589 If POS is out of range, the value is nil."
590 (si:char-before (or pos (point)))))))
591 (void-function ; non-Mule.
592 (defun-maybe char-before (&optional pos)
594 Return character in current buffer preceding position POS.
595 POS is an integer or a buffer pointer.
596 If POS is out of range, the value is nil."
599 (and (= (goto-char pos) (point))
603 (preceding-char))))))))
605 ;; emulating char-after of Emacs 20.
606 (static-condition-case nil
607 ;; compile-time check.
609 ;; XXX: this file is already loaded at compile-time,
610 ;; so this test will always success.
612 ;; If our definition is found at compile-time, signal an error.
613 ;; XXX: should signal more specific error.
614 (if (get 'char-after 'defun-maybe)
616 (wrong-number-of-arguments ; v18, v19
618 (or (fboundp 'si:char-after)
620 (fset 'si:char-after (symbol-function 'char-after))
621 (put 'char-after 'defun-maybe t)
622 (defun char-after (&optional pos)
624 Return character in current buffer at position POS.
625 POS is an integer or a buffer pointer.
626 If POS is out of range, the value is nil."
627 (si:char-after (or pos (point)))))))
628 (void-function ; NEVER happen?
630 (defun-maybe char-after (&optional pos)
632 Return character in current buffer at position POS.
633 POS is an integer or a buffer pointer.
634 If POS is out of range, the value is nil."
637 (and (= (goto-char pos) (point))
642 (error ; found our definition at compile-time.
646 (wrong-number-of-arguments ; v18, v19
647 (or (fboundp 'si:char-after)
649 (fset 'si:char-after (symbol-function 'char-after))
650 (put 'char-after 'defun-maybe t)
651 (defun char-after (&optional pos)
653 Return character in current buffer at position POS.
654 POS is an integer or a buffer pointer.
655 If POS is out of range, the value is nil."
656 (si:char-after (or pos (point)))))))
657 (void-function ; NEVER happen?
658 (defun-maybe char-after (&optional pos)
660 Return character in current buffer at position POS.
661 POS is an integer or a buffer pointer.
662 If POS is out of range, the value is nil."
665 (and (= (goto-char pos) (point))
669 (following-char))))))))
672 ;;; @ Emacs 20.3 emulation
675 ;; imported from emacs-20.3/lisp/files.el.
676 (defvar-maybe temporary-file-directory
677 (file-name-as-directory
678 (cond ((memq system-type '(ms-dos windows-nt))
679 (or (getenv "TEMP") (getenv "TMPDIR") (getenv "TMP") "c:/temp"))
680 ((memq system-type '(vax-vms axp-vms))
681 (or (getenv "TMPDIR") (getenv "TMP") (getenv "TEMP") "SYS$SCRATCH:"))
683 (or (getenv "TMPDIR") (getenv "TMP") (getenv "TEMP") "/tmp"))))
684 "The directory for writing temporary files.")
686 (defun-maybe line-beginning-position (&optional n)
687 "Return the character position of the first character on the current line.
688 With argument N not nil or 1, move forward N - 1 lines first.
689 If scan reaches end of buffer, return that position.
690 This function does not move point."
692 (forward-line (1- (or n 1)))
695 (defun-maybe line-end-position (&optional n)
696 "Return the character position of the last character on the current line.
697 With argument N not nil or 1, move forward N - 1 lines first.
698 If scan reaches end of buffer, return that position.
699 This function does not move point."
701 (end-of-line (or n 1))
704 (defun-maybe string (&rest chars)
705 "Concatenate all the argument characters and make the result a string."
706 (mapconcat (function char-to-string) chars ""))
709 ;;; @ XEmacs emulation
712 (defun-maybe find-face (face-or-name)
713 "Retrieve the face of the given name.
714 If FACE-OR-NAME is a face object, it is simply returned.
715 Otherwise, FACE-OR-NAME should be a symbol. If there is no such face,
716 nil is returned. Otherwise the associated face object is returned.
717 \[XEmacs emulating function]"
718 (car (memq face-or-name (face-list))))
720 (defun-maybe point-at-bol (&optional n buffer)
721 "Return the character position of the first character on the current line.
722 With argument N not nil or 1, move forward N - 1 lines first.
723 If scan reaches end of buffer, return that position.
724 This function does not move point.
725 \[XEmacs emulating function]"
727 (if buffer (set-buffer buffer))
728 (forward-line (1- (or n 1)))
731 (defun-maybe point-at-eol (&optional n buffer)
732 "Return the character position of the last character on the current line.
733 With argument N not nil or 1, move forward N - 1 lines first.
734 If scan reaches end of buffer, return that position.
735 This function does not move point.
736 \[XEmacs emulating function]"
738 (if buffer (set-buffer buffer))
739 (end-of-line (or n 1))
742 (defsubst-maybe define-obsolete-function-alias (oldfun newfun)
743 "Define OLDFUN as an obsolete alias for function NEWFUN.
744 This makes calling OLDFUN equivalent to calling NEWFUN and marks OLDFUN
746 \[XEmacs emulating function]"
747 (defalias oldfun newfun)
748 (make-obsolete oldfun newfun))
750 (when (subr-fboundp 'read-event)
751 ;; for Emacs 19 or later
753 (defun-maybe-cond next-command-event (&optional event prompt)
754 "Read an event object from the input stream.
755 If EVENT is non-nil, it should be an event object and will be filled
756 in and returned; otherwise a new event object will be created and
758 If PROMPT is non-nil, it should be a string and will be displayed in
759 the echo area while this function is waiting for an event.
760 \[XEmacs emulating function]"
761 ((subr-fboundp 'string)
762 ;; for Emacs 20.3 or later
763 (read-event prompt t)
766 (if prompt (message prompt))
770 (defsubst-maybe character-to-event (ch)
771 "Convert keystroke CH into an event structure, replete with bucky bits.
772 Note that CH (the keystroke specifier) can be an integer, a character
773 or a symbol such as 'clear. [XEmacs emulating function]"
776 (defsubst-maybe event-to-character (event)
777 "Return the character approximation to the given event object.
778 If the event isn't a keypress, this returns nil.
779 \[XEmacs emulating function]"
780 (cond ((symbolp event)
781 ;; mask is (BASE-TYPE MODIFIER-BITS) or nil.
782 (let ((mask (get event 'event-symbol-element-mask)))
784 (let ((base (get (car mask) 'ascii-character)))
786 (logior base (car (cdr mask)))
788 ((integerp event) event)))
792 ;;; @ MULE 2 emulation
795 (defun-maybe-cond cancel-undo-boundary ()
796 "Cancel undo boundary. [MULE 2.3 emulating function]"
797 ((boundp 'buffer-undo-list)
798 ;; for Emacs 19.7 or later
799 (if (and (consp buffer-undo-list)
801 (null (car buffer-undo-list)))
802 (setq buffer-undo-list (cdr buffer-undo-list))
805 ;; for anything older than Emacs 19.7.