simple.el 86.2 KB
Newer Older
Eric S. Raymond's avatar
Eric S. Raymond committed
1 2
;;; simple.el --- basic editing commands for Emacs

3
;; Copyright (C) 1985, 1986, 1987, 1993, 1994 Free Software Foundation, Inc.
Jim Blandy's avatar
Jim Blandy committed
4 5 6 7 8

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
Eric S. Raymond's avatar
Eric S. Raymond committed
9
;; the Free Software Foundation; either version 2, or (at your option)
Jim Blandy's avatar
Jim Blandy committed
10 11 12 13 14 15 16 17 18 19 20
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to
;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

21 22 23 24 25
;;; Commentary:

;; A grab-bag of basic Emacs commands not specifically related to some
;; major mode or to file-handling.

Eric S. Raymond's avatar
Eric S. Raymond committed
26
;;; Code:
Jim Blandy's avatar
Jim Blandy committed
27 28

(defun open-line (arg)
29
  "Insert a newline and leave point before it.
30 31 32
If there is a fill prefix, insert the fill prefix on the new line
if the line would have been empty.
With arg N, insert N newlines."
Jim Blandy's avatar
Jim Blandy committed
33
  (interactive "*p")
34 35
  (let* ((do-fill-prefix (and fill-prefix (bolp)))
	 (flag (and (null do-fill-prefix) (bolp) (not (bobp)))))
36 37 38 39 40 41 42 43
    ;; If this is a simple case, and we are at the beginning of a line,
    ;; actually insert the newline *before* the preceding newline
    ;; instead of after.  That makes better display behavior.
    (if flag
	(progn
	  ;; If undo is enabled, don't let this hack be visible:
	  ;; record the real value of point as the place to move back to
	  ;; if we undo this insert.
44
	  (if (not (eq buffer-undo-list t))
45 46
	      (setq buffer-undo-list (cons (point) buffer-undo-list)))
	  (forward-char -1)))
47 48 49 50 51 52
    (save-excursion
      (while (> arg 0)
	(if do-fill-prefix (insert fill-prefix))
	(insert ?\n)
	(setq arg (1- arg))))
    (end-of-line)
Jim Blandy's avatar
Jim Blandy committed
53 54 55 56 57 58 59 60 61 62 63 64 65 66
    (if flag (forward-char 1))))

(defun split-line ()
  "Split current line, moving portion beyond point vertically down."
  (interactive "*")
  (skip-chars-forward " \t")
  (let ((col (current-column))
	(pos (point)))
    (insert ?\n)
    (indent-to col 0)
    (goto-char pos)))

(defun quoted-insert (arg)
  "Read next input character and insert it.
67
This is useful for inserting control characters.
Jim Blandy's avatar
Jim Blandy committed
68
You may also type up to 3 octal digits, to insert a character with that code.
69 70 71 72 73 74 75 76 77

In overwrite mode, this function inserts the character anyway, and
does not handle octal digits specially.  This means that if you use
overwrite as your normal editing mode, you can use this function to
insert characters when necessary.

In binary overwrite mode, this function does overwrite, and octal
digits are interpreted as a character code.  This is supposed to make
this function useful in editing binary files."
Jim Blandy's avatar
Jim Blandy committed
78
  (interactive "*p")
79 80 81 82 83 84
  (let ((char (if (or (not overwrite-mode)
		      (eq overwrite-mode 'overwrite-mode-binary))
		  (read-quoted-char)
		(read-char))))
    (if (eq overwrite-mode 'overwrite-mode-binary)
	(delete-char arg))
85
    (insert-char char arg)))
Jim Blandy's avatar
Jim Blandy committed
86 87 88

(defun delete-indentation (&optional arg)
  "Join this line to previous and fix up whitespace at join.
89
If there is a fill prefix, delete it from the beginning of this line.
Jim Blandy's avatar
Jim Blandy committed
90 91 92 93 94 95 96
With argument, join this line to following line."
  (interactive "*P")
  (beginning-of-line)
  (if arg (forward-line 1))
  (if (eq (preceding-char) ?\n)
      (progn
	(delete-region (point) (1- (point)))
97 98 99
	;; If the second line started with the fill prefix,
	;; delete the prefix.
	(if (and fill-prefix
100
		 (<= (+ (point) (length fill-prefix)) (point-max))
101 102 103 104
		 (string= fill-prefix
			  (buffer-substring (point)
					    (+ (point) (length fill-prefix)))))
	    (delete-region (point) (+ (point) (length fill-prefix))))
Jim Blandy's avatar
Jim Blandy committed
105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142
	(fixup-whitespace))))

(defun fixup-whitespace ()
  "Fixup white space between objects around point.
Leave one space or none, according to the context."
  (interactive "*")
  (save-excursion
    (delete-horizontal-space)
    (if (or (looking-at "^\\|\\s)")
	    (save-excursion (forward-char -1)
			    (looking-at "$\\|\\s(\\|\\s'")))
	nil
      (insert ?\ ))))

(defun delete-horizontal-space ()
  "Delete all spaces and tabs around point."
  (interactive "*")
  (skip-chars-backward " \t")
  (delete-region (point) (progn (skip-chars-forward " \t") (point))))

(defun just-one-space ()
  "Delete all spaces and tabs around point, leaving one space."
  (interactive "*")
  (skip-chars-backward " \t")
  (if (= (following-char) ? )
      (forward-char 1)
    (insert ? ))
  (delete-region (point) (progn (skip-chars-forward " \t") (point))))

(defun delete-blank-lines ()
  "On blank line, delete all surrounding blank lines, leaving just one.
On isolated blank line, delete that one.
On nonblank line, delete all blank lines that follow it."
  (interactive "*")
  (let (thisblank singleblank)
    (save-excursion
      (beginning-of-line)
      (setq thisblank (looking-at "[ \t]*$"))
Jim Blandy's avatar
Jim Blandy committed
143
      ;; Set singleblank if there is just one blank line here.
Jim Blandy's avatar
Jim Blandy committed
144 145 146 147 148 149
      (setq singleblank
	    (and thisblank
		 (not (looking-at "[ \t]*\n[ \t]*$"))
		 (or (bobp)
		     (progn (forward-line -1)
			    (not (looking-at "[ \t]*$")))))))
Jim Blandy's avatar
Jim Blandy committed
150
    ;; Delete preceding blank lines, and this one too if it's the only one.
Jim Blandy's avatar
Jim Blandy committed
151 152 153 154 155 156 157 158
    (if thisblank
	(progn
	  (beginning-of-line)
	  (if singleblank (forward-line 1))
	  (delete-region (point)
			 (if (re-search-backward "[^ \t\n]" nil t)
			     (progn (forward-line 1) (point))
			   (point-min)))))
Jim Blandy's avatar
Jim Blandy committed
159 160
    ;; Delete following blank lines, unless the current line is blank
    ;; and there are no following blank lines.
Jim Blandy's avatar
Jim Blandy committed
161 162 163 164 165 166 167
    (if (not (and thisblank singleblank))
	(save-excursion
	  (end-of-line)
	  (forward-line 1)
	  (delete-region (point)
			 (if (re-search-forward "[^ \t\n]" nil t)
			     (progn (beginning-of-line) (point))
Jim Blandy's avatar
Jim Blandy committed
168 169 170 171 172
			   (point-max)))))
    ;; Handle the special case where point is followed by newline and eob.
    ;; Delete the line, leaving point at eob.
    (if (looking-at "^[ \t]*\n\\'")
	(delete-region (point) (point-max)))))
Jim Blandy's avatar
Jim Blandy committed
173 174 175 176 177 178 179 180 181

(defun back-to-indentation ()
  "Move point to the first non-whitespace character on this line."
  (interactive)
  (beginning-of-line 1)
  (skip-chars-forward " \t"))

(defun newline-and-indent ()
  "Insert a newline, then indent according to major mode.
182
Indentation is done using the value of `indent-line-function'.
Jim Blandy's avatar
Jim Blandy committed
183
In programming language modes, this is the same as TAB.
184 185
In some text modes, where TAB inserts a tab, this command indents to the
column specified by the variable `left-margin'."
Jim Blandy's avatar
Jim Blandy committed
186 187
  (interactive "*")
  (delete-region (point) (progn (skip-chars-backward " \t") (point)))
Jim Blandy's avatar
Jim Blandy committed
188
  (newline)
Jim Blandy's avatar
Jim Blandy committed
189 190 191 192 193
  (indent-according-to-mode))

(defun reindent-then-newline-and-indent ()
  "Reindent current line, insert newline, then indent the new line.
Indentation of both lines is done according to the current major mode,
194
which means calling the current value of `indent-line-function'.
Jim Blandy's avatar
Jim Blandy committed
195 196
In programming language modes, this is the same as TAB.
In some text modes, where TAB inserts a tab, this indents to the
197
column specified by the variable `left-margin'."
Jim Blandy's avatar
Jim Blandy committed
198 199 200 201
  (interactive "*")
  (save-excursion
    (delete-region (point) (progn (skip-chars-backward " \t") (point)))
    (indent-according-to-mode))
Jim Blandy's avatar
Jim Blandy committed
202
  (newline)
Jim Blandy's avatar
Jim Blandy committed
203 204
  (indent-according-to-mode))

205 206 207 208 209 210 211 212 213 214 215 216
;; Internal subroutine of delete-char
(defun kill-forward-chars (arg)
  (if (listp arg) (setq arg (car arg)))
  (if (eq arg '-) (setq arg -1))
  (kill-region (point) (+ (point) arg)))

;; Internal subroutine of backward-delete-char
(defun kill-backward-chars (arg)
  (if (listp arg) (setq arg (car arg)))
  (if (eq arg '-) (setq arg -1))
  (kill-region (point) (- (point) arg)))

Jim Blandy's avatar
Jim Blandy committed
217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251
(defun backward-delete-char-untabify (arg &optional killp)
  "Delete characters backward, changing tabs into spaces.
Delete ARG chars, and kill (save in kill ring) if KILLP is non-nil.
Interactively, ARG is the prefix arg (default 1)
and KILLP is t if prefix arg is was specified."
  (interactive "*p\nP")
  (let ((count arg))
    (save-excursion
      (while (and (> count 0) (not (bobp)))
	(if (= (preceding-char) ?\t)
	    (let ((col (current-column)))
	      (forward-char -1)
	      (setq col (- col (current-column)))
	      (insert-char ?\ col)
	      (delete-char 1)))
	(forward-char -1)
	(setq count (1- count)))))
  (delete-backward-char arg killp)
  ;; In overwrite mode, back over columns while clearing them out,
  ;; unless at end of line.
  (and overwrite-mode (not (eolp))
       (save-excursion (insert-char ?\  arg))))

(defun zap-to-char (arg char)
  "Kill up to and including ARG'th occurrence of CHAR.
Goes backward if ARG is negative; error if CHAR not found."
  (interactive "p\ncZap to char: ")
  (kill-region (point) (progn
			 (search-forward (char-to-string char) nil nil arg)
;			 (goto-char (if (> arg 0) (1- (point)) (1+ (point))))
			 (point))))

(defun beginning-of-buffer (&optional arg)
  "Move point to the beginning of the buffer; leave mark at previous position.
With arg N, put point N/10 of the way from the true beginning.
252 253

Don't use this command in Lisp programs!
Jim Blandy's avatar
Jim Blandy committed
254 255 256 257 258 259 260 261 262 263 264 265 266 267 268
\(goto-char (point-min)) is faster and avoids clobbering the mark."
  (interactive "P")
  (push-mark)
  (goto-char (if arg
		 (if (> (buffer-size) 10000)
		     ;; Avoid overflow for large buffer sizes!
		     (* (prefix-numeric-value arg)
			(/ (buffer-size) 10))
		   (/ (+ 10 (* (buffer-size) (prefix-numeric-value arg))) 10))
	       (point-min)))
  (if arg (forward-line 1)))

(defun end-of-buffer (&optional arg)
  "Move point to the end of the buffer; leave mark at previous position.
With arg N, put point N/10 of the way from the true end.
269 270

Don't use this command in Lisp programs!
Jim Blandy's avatar
Jim Blandy committed
271 272 273 274 275 276 277 278 279 280 281
\(goto-char (point-max)) is faster and avoids clobbering the mark."
  (interactive "P")
  (push-mark)
  (goto-char (if arg
		 (- (1+ (buffer-size))
		    (if (> (buffer-size) 10000)
			;; Avoid overflow for large buffer sizes!
			(* (prefix-numeric-value arg)
			   (/ (buffer-size) 10))
		      (/ (* (buffer-size) (prefix-numeric-value arg)) 10)))
	       (point-max)))
Eric S. Raymond's avatar
Eric S. Raymond committed
282 283
  ;; If we went to a place in the middle of the buffer,
  ;; adjust it to the beginning of a line.
Jim Blandy's avatar
Jim Blandy committed
284
  (if arg (forward-line 1)
Eric S. Raymond's avatar
Eric S. Raymond committed
285 286 287 288 289 290 291 292
    ;; If the end of the buffer is not already on the screen,
    ;; then scroll specially to put it near, but not at, the bottom.
    (if (let ((old-point (point)))
	  (save-excursion
		    (goto-char (window-start))
		    (vertical-motion (window-height))
		    (< (point) old-point)))
	(recenter -3))))
Jim Blandy's avatar
Jim Blandy committed
293 294

(defun mark-whole-buffer ()
Jim Blandy's avatar
Jim Blandy committed
295 296 297 298
  "Put point at beginning and mark at end of buffer.
You probably should not use this function in Lisp programs;
it is usually a mistake for a Lisp function to use any subroutine
that uses or sets the mark."
Jim Blandy's avatar
Jim Blandy committed
299 300
  (interactive)
  (push-mark (point))
301
  (push-mark (point-max) nil t)
Jim Blandy's avatar
Jim Blandy committed
302 303 304
  (goto-char (point-min)))

(defun count-lines-region (start end)
305
  "Print number of lines and characters in the region."
Jim Blandy's avatar
Jim Blandy committed
306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322
  (interactive "r")
  (message "Region has %d lines, %d characters"
	   (count-lines start end) (- end start)))

(defun what-line ()
  "Print the current line number (in the buffer) of point."
  (interactive)
  (save-restriction
    (widen)
    (save-excursion
      (beginning-of-line)
      (message "Line %d"
	       (1+ (count-lines 1 (point)))))))

(defun count-lines (start end)
  "Return number of lines between START and END.
This is usually the number of newlines between them,
323
but can be one more if START is not equal to END
Jim Blandy's avatar
Jim Blandy committed
324
and the greater of them is not at the start of a line."
325 326 327 328 329 330 331 332 333 334 335
  (save-match-data
    (save-excursion
      (save-restriction
	(narrow-to-region start end)
	(goto-char (point-min))
	(if (eq selective-display t)
	    (let ((done 0))
	      (while (re-search-forward "[\n\C-m]" nil t 40)
		(setq done (+ 40 done)))
	      (while (re-search-forward "[\n\C-m]" nil t 1)
		(setq done (+ 1 done)))
336 337 338 339 340
	      (goto-char (point-max))
	      (if (and (/= start end)
		       (not (bolp)))
		  (1+ done)
		done))
341
	  (- (buffer-size) (forward-line (buffer-size))))))))
Jim Blandy's avatar
Jim Blandy committed
342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376

(defun what-cursor-position ()
  "Print info on cursor position (on screen and within buffer)."
  (interactive)
  (let* ((char (following-char))
	 (beg (point-min))
	 (end (point-max))
         (pos (point))
	 (total (buffer-size))
	 (percent (if (> total 50000)
		      ;; Avoid overflow from multiplying by 100!
		      (/ (+ (/ total 200) (1- pos)) (max (/ total 100) 1))
		    (/ (+ (/ total 2) (* 100 (1- pos))) (max total 1))))
	 (hscroll (if (= (window-hscroll) 0)
		      ""
		    (format " Hscroll=%d" (window-hscroll))))
	 (col (current-column)))
    (if (= pos end)
	(if (or (/= beg 1) (/= end (1+ total)))
	    (message "point=%d of %d(%d%%) <%d - %d>  column %d %s"
		     pos total percent beg end col hscroll)
	  (message "point=%d of %d(%d%%)  column %d %s"
		   pos total percent col hscroll))
      (if (or (/= beg 1) (/= end (1+ total)))
	  (message "Char: %s (0%o)  point=%d of %d(%d%%) <%d - %d>  column %d %s"
		   (single-key-description char) char pos total percent beg end col hscroll)
	(message "Char: %s (0%o)  point=%d of %d(%d%%)  column %d %s"
		 (single-key-description char) char pos total percent col hscroll)))))

(defun fundamental-mode ()
  "Major mode not specialized for anything in particular.
Other major modes are defined by comparison with this one."
  (interactive)
  (kill-all-local-variables))

377
(defvar read-expression-map (cons 'keymap minibuffer-local-map)
378 379 380
  "Minibuffer keymap used for reading Lisp expressions.")
(define-key read-expression-map "\M-\t" 'lisp-complete-symbol)

Jim Blandy's avatar
Jim Blandy committed
381 382
(put 'eval-expression 'disabled t)

383 384 385
(defvar read-expression-history nil)

;; We define this, rather than making `eval' interactive,
Jim Blandy's avatar
Jim Blandy committed
386 387 388
;; for the sake of completion of names like eval-region, eval-current-buffer.
(defun eval-expression (expression)
  "Evaluate EXPRESSION and print value in minibuffer.
389
Value is also consed on to front of the variable `values'."
390
  (interactive
391 392 393
   (list (read-from-minibuffer "Eval: "
			       nil read-expression-map t
			       'read-expression-history)))
Jim Blandy's avatar
Jim Blandy committed
394 395 396 397 398 399 400
  (setq values (cons (eval expression) values))
  (prin1 (car values) t))

(defun edit-and-eval-command (prompt command)
  "Prompting with PROMPT, let user edit COMMAND and eval result.
COMMAND is a Lisp expression.  Let user edit that expression in
the minibuffer, then read and evaluate the result."
401 402 403 404
  (let ((command (read-from-minibuffer prompt
				       (prin1-to-string command)
				       read-expression-map t
				       '(command-history . 1))))
Jim Blandy's avatar
Jim Blandy committed
405 406
    (eval command)))

407
(defun repeat-complex-command (arg)
Jim Blandy's avatar
Jim Blandy committed
408 409 410 411 412 413
  "Edit and re-evaluate last complex command, or ARGth from last.
A complex command is one which used the minibuffer.
The command is placed in the minibuffer as a Lisp form for editing.
The result is executed, repeating the command as changed.
If the command has been changed or is not the most recent previous command
it is added to the front of the command history.
414 415
You can use the minibuffer history commands \\<minibuffer-local-map>\\[next-history-element] and \\[previous-history-element]
to get different commands to edit and resubmit."
Jim Blandy's avatar
Jim Blandy committed
416
  (interactive "p")
417
  (let ((elt (nth (1- arg) command-history))
418
	(minibuffer-history-position arg)
419
	(minibuffer-history-sexp-flag t)
Jim Blandy's avatar
Jim Blandy committed
420 421
	newcmd)
    (if elt
422
	(progn
423 424 425 426 427
	  (setq newcmd
		(read-from-minibuffer
		 "Redo: " (prin1-to-string elt) read-expression-map t
		 (cons 'command-history arg)))

428 429 430 431 432 433 434 435 436
	  ;; If command was added to command-history as a string,
	  ;; get rid of that.  We want only evallable expressions there.
	  (if (stringp (car command-history))
	      (setq command-history (cdr command-history)))

	  ;; If command to be redone does not match front of history,
	  ;; add it to the history.
	  (or (equal newcmd (car command-history))
	      (setq command-history (cons newcmd command-history)))
Jim Blandy's avatar
Jim Blandy committed
437 438
	  (eval newcmd))
      (ding))))
439

440 441 442 443 444 445 446 447
(defvar minibuffer-history nil
  "Default minibuffer history list.
This is used for all minibuffer input
except when an alternate history list is specified.")
(defvar minibuffer-history-sexp-flag nil
  "Nonzero when doing history operations on `command-history'.
More generally, indicates that the history list being acted on
contains expressions rather than strings.")
448 449
(setq minibuffer-history-variable 'minibuffer-history)
(setq minibuffer-history-position nil)
450
(defvar minibuffer-history-search-history nil)
451

Jim Blandy's avatar
Jim Blandy committed
452
(mapcar
453 454 455 456 457 458 459 460 461 462
 (lambda (key-and-command)
   (mapcar
    (lambda (keymap-and-completionp)
      ;; Arg is (KEYMAP-SYMBOL . COMPLETION-MAP-P).
      ;; If the cdr of KEY-AND-COMMAND (the command) is a cons,
      ;; its car is used if COMPLETION-MAP-P is nil, its cdr if it is t.
      (define-key (symbol-value (car keymap-and-completionp))
	(car key-and-command)
	(let ((command (cdr key-and-command)))
	  (if (consp command)
463 464 465 466
	      ;; (and ... nil) => ... turns back on the completion-oriented
	      ;; history commands which rms turned off since they seem to
	      ;; do things he doesn't like.
	      (if (and (cdr keymap-and-completionp) nil) ;XXX turned off
467
		  (progn (error "EMACS BUG!") (cdr command))
468 469 470 471 472 473 474
		(car command))
	    command))))
    '((minibuffer-local-map . nil)
      (minibuffer-local-ns-map . nil)
      (minibuffer-local-completion-map . t)
      (minibuffer-local-must-match-map . t)
      (read-expression-map . nil))))
475 476 477 478
 '(("\en" . (next-history-element . next-complete-history-element))
   ([next] . (next-history-element . next-complete-history-element))
   ("\ep" . (previous-history-element . previous-complete-history-element))
   ([prior] . (previous-history-element . previous-complete-history-element))
Jim Blandy's avatar
Jim Blandy committed
479 480
   ("\er" . previous-matching-history-element)
   ("\es" . next-matching-history-element)))
481 482

(defun previous-matching-history-element (regexp n)
483 484 485 486 487
  "Find the previous history element that matches REGEXP.
\(Previous history elements refer to earlier actions.)
With prefix argument N, search for Nth previous match.
If N is negative, find the next or Nth next match."
  (interactive
488 489 490 491 492 493 494 495 496 497 498 499
   (let* ((enable-recursive-minibuffers t)
	  (minibuffer-history-sexp-flag nil)
	  (regexp (read-from-minibuffer "Previous element matching (regexp): "
					nil
					minibuffer-local-map
					nil
					'minibuffer-history-search-history)))
     ;; Use the last regexp specified, by default, if input is empty.
     (list (if (string= regexp "")
	       (setcar minibuffer-history-search-history
		       (nth 1 minibuffer-history-search-history))
	     regexp)
500
	   (prefix-numeric-value current-prefix-arg))))
501
  (let ((history (symbol-value minibuffer-history-variable))
502
	prevpos
503 504 505 506 507 508
	(pos minibuffer-history-position))
    (while (/= n 0)
      (setq prevpos pos)
      (setq pos (min (max 1 (+ pos (if (< n 0) -1 1))) (length history)))
      (if (= pos prevpos)
	  (error (if (= pos 1)
509 510
		     "No later matching history item"
		   "No earlier matching history item")))
511 512 513 514
      (if (string-match regexp
			(if minibuffer-history-sexp-flag
			    (prin1-to-string (nth (1- pos) history))
			  (nth (1- pos) history)))
515
	  (setq n (+ n (if (< n 0) 1 -1)))))
516 517 518 519 520 521
    (setq minibuffer-history-position pos)
    (erase-buffer)
    (let ((elt (nth (1- pos) history)))
      (insert (if minibuffer-history-sexp-flag
		  (prin1-to-string elt)
		elt)))
522 523 524 525
      (goto-char (point-min)))
  (if (or (eq (car (car command-history)) 'previous-matching-history-element)
	  (eq (car (car command-history)) 'next-matching-history-element))
      (setq command-history (cdr command-history))))
526 527

(defun next-matching-history-element (regexp n)
528 529 530 531 532
  "Find the next history element that matches REGEXP.
\(The next history element refers to a more recent action.)
With prefix argument N, search for Nth next match.
If N is negative, find the previous or Nth previous match."
  (interactive
533 534 535 536 537 538 539 540 541 542 543 544
   (let* ((enable-recursive-minibuffers t)
	  (minibuffer-history-sexp-flag nil)
	  (regexp (read-from-minibuffer "Next element matching (regexp): "
					nil
					minibuffer-local-map
					nil
					'minibuffer-history-search-history)))
     ;; Use the last regexp specified, by default, if input is empty.
     (list (if (string= regexp "")
	       (setcar minibuffer-history-search-history
		       (nth 1 minibuffer-history-search-history))
	     regexp)
545
	   (prefix-numeric-value current-prefix-arg))))
546
  (previous-matching-history-element regexp (- n)))
Jim Blandy's avatar
Jim Blandy committed
547

548 549
(defun next-history-element (n)
  "Insert the next element of the minibuffer history into the minibuffer."
Jim Blandy's avatar
Jim Blandy committed
550
  (interactive "p")
551 552 553 554
  (let ((narg (min (max 1 (- minibuffer-history-position n))
		   (length (symbol-value minibuffer-history-variable)))))
    (if (= minibuffer-history-position narg)
	(error (if (= minibuffer-history-position 1)
555 556
		   "End of history; no next item"
		 "Beginning of history; no preceding item"))
Jim Blandy's avatar
Jim Blandy committed
557
      (erase-buffer)
558
      (setq minibuffer-history-position narg)
559 560 561 562 563
      (let ((elt (nth (1- minibuffer-history-position)
		      (symbol-value minibuffer-history-variable))))
	(insert
	 (if minibuffer-history-sexp-flag
	     (prin1-to-string elt)
564
	   elt)))
Jim Blandy's avatar
Jim Blandy committed
565 566
      (goto-char (point-min)))))

567
(defun previous-history-element (n)
Richard M. Stallman's avatar
Richard M. Stallman committed
568
  "Inserts the previous element of the minibuffer history into the minibuffer."
Jim Blandy's avatar
Jim Blandy committed
569
  (interactive "p")
570
  (next-history-element (- n)))
571 572

(defun next-complete-history-element (n)
573
  "Get next element of history which is a completion of minibuffer contents."
574
  (interactive "p")
575 576 577 578 579 580 581
  (let ((point-at-start (point)))
    (next-matching-history-element
     (concat "^" (regexp-quote (buffer-substring (point-min) (point)))) n)
    ;; next-matching-history-element always puts us at (point-min).
    ;; Move to the position we were at before changing the buffer contents.
    ;; This is still sensical, because the text before point has not changed.
    (goto-char point-at-start)))
582 583

(defun previous-complete-history-element (n)
584 585
  "\
Get previous element of history which is a completion of minibuffer contents."
586 587
  (interactive "p")
  (next-complete-history-element (- n)))
588

Jim Blandy's avatar
Jim Blandy committed
589 590 591 592 593 594 595 596 597 598 599
(defun goto-line (arg)
  "Goto line ARG, counting from line 1 at beginning of buffer."
  (interactive "NGoto line: ")
  (save-restriction
    (widen)
    (goto-char 1)
    (if (eq selective-display t)
	(re-search-forward "[\n\C-m]" nil 'end (1- arg))
      (forward-line (1- arg)))))

;Put this on C-x u, so we can force that rather than C-_ into startup msg
600
(define-function 'advertised-undo 'undo)
Jim Blandy's avatar
Jim Blandy committed
601 602 603 604 605 606

(defun undo (&optional arg)
  "Undo some previous changes.
Repeat this command to undo more changes.
A numeric argument serves as a repeat count."
  (interactive "*p")
607 608 609
  ;; If we don't get all the way thru, make last-command indicate that
  ;; for the following command.
  (setq this-command t)
610 611
  (let ((modified (buffer-modified-p))
	(recent-save (recent-auto-save-p)))
Jim Blandy's avatar
Jim Blandy committed
612 613
    (or (eq (selected-window) (minibuffer-window))
	(message "Undo!"))
Jim Blandy's avatar
Jim Blandy committed
614 615 616 617 618
    (or (eq last-command 'undo)
	(progn (undo-start)
	       (undo-more 1)))
    (undo-more (or arg 1))
    (and modified (not (buffer-modified-p))
619 620 621
	 (delete-auto-save-file-if-necessary recent-save)))
  ;; If we do get all the way thru, make this-command indicate that.
  (setq this-command 'undo))
Jim Blandy's avatar
Jim Blandy committed
622

623 624 625
(defvar pending-undo-list nil
  "Within a run of consecutive undo commands, list remaining to be undone.")

Jim Blandy's avatar
Jim Blandy committed
626
(defun undo-start ()
627 628
  "Set `pending-undo-list' to the front of the undo list.
The next call to `undo-more' will undo the most recently made change."
Jim Blandy's avatar
Jim Blandy committed
629 630 631 632 633 634
  (if (eq buffer-undo-list t)
      (error "No undo information in this buffer"))
  (setq pending-undo-list buffer-undo-list))

(defun undo-more (count)
  "Undo back N undo-boundaries beyond what was already undone recently.
635 636
Call `undo-start' to get ready to undo recent changes,
then call `undo-more' one or more times to undo them."
Jim Blandy's avatar
Jim Blandy committed
637 638 639 640
  (or pending-undo-list
      (error "No further undo information"))
  (setq pending-undo-list (primitive-undo count pending-undo-list)))

641 642 643
(defvar shell-command-history nil
  "History list for some commands that read shell commands.")

Jim Blandy's avatar
Jim Blandy committed
644 645 646 647 648 649 650
(defun shell-command (command &optional flag)
  "Execute string COMMAND in inferior shell; display output, if any.
If COMMAND ends in ampersand, execute it asynchronously.
 
Optional second arg non-nil (prefix arg, if interactive)
means insert output in current buffer after point (leave mark after it).
This cannot be done asynchronously."
651 652 653
  (interactive (list (read-from-minibuffer "Shell command: "
					   nil nil nil 'shell-command-history)
		     current-prefix-arg))
Jim Blandy's avatar
Jim Blandy committed
654 655 656 657 658 659 660 661 662 663
  (if flag
      (progn (barf-if-buffer-read-only)
	     (push-mark)
	     ;; We do not use -f for csh; we will not support broken use of
	     ;; .cshrcs.  Even the BSD csh manual says to use
	     ;; "if ($?prompt) exit" before things which are not useful
	     ;; non-interactively.  Besides, if someone wants their other
	     ;; aliases for shell commands then they can still have them.
	     (call-process shell-file-name nil t nil
			   "-c" command)
664 665 666 667 668 669
	     ;; This is like exchange-point-and-mark, but doesn't activate the mark.
	     ;; It is cleaner to avoid activation, even though the command
	     ;; loop would deactivate the mark because we inserted text.
	     (goto-char (prog1 (mark t)
			  (set-marker (mark-marker) (point)
				      (current-buffer)))))
Jim Blandy's avatar
Jim Blandy committed
670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745
    ;; Preserve the match data in case called from a program.
    (let ((data (match-data)))
      (unwind-protect
	  (if (string-match "[ \t]*&[ \t]*$" command)
	      ;; Command ending with ampersand means asynchronous.
	      (let ((buffer (get-buffer-create "*shell-command*")) 
		    (directory default-directory)
		    proc)
		;; Remove the ampersand.
		(setq command (substring command 0 (match-beginning 0)))
		;; If will kill a process, query first.
		(setq proc (get-buffer-process buffer))
		(if proc
		    (if (yes-or-no-p "A command is running.  Kill it? ")
			(kill-process proc)
		      (error "Shell command in progress")))
		(save-excursion
		  (set-buffer buffer)
		  (erase-buffer)
		  (display-buffer buffer)
		  (setq default-directory directory)
		  (setq proc (start-process "Shell" buffer 
					    shell-file-name "-c" command))
		  (setq mode-line-process '(": %s"))
		  (set-process-sentinel proc 'shell-command-sentinel)
		  (set-process-filter proc 'shell-command-filter)
		  ))
	    (shell-command-on-region (point) (point) command nil))
	(store-match-data data)))))

;; We have a sentinel to prevent insertion of a termination message
;; in the buffer itself.
(defun shell-command-sentinel (process signal)
  (if (memq (process-status process) '(exit signal))
      (progn
	(message "%s: %s." 
		 (car (cdr (cdr (process-command process))))
		 (substring signal 0 -1))
	(save-excursion
	  (set-buffer (process-buffer process))
	  (setq mode-line-process nil))
	(delete-process process))))

(defun shell-command-filter (proc string)
  ;; Do save-excursion by hand so that we can leave point numerically unchanged
  ;; despite an insertion immediately after it.
  (let* ((obuf (current-buffer))
	 (buffer (process-buffer proc))
	 opoint
	 (window (get-buffer-window buffer))
	 (pos (window-start window)))
    (unwind-protect
	(progn
	  (set-buffer buffer)
	  (setq opoint (point))
	  (goto-char (point-max))
	  (insert-before-markers string))
      ;; insert-before-markers moved this marker: set it back.
      (set-window-start window pos)
      ;; Finish our save-excursion.
      (goto-char opoint)
      (set-buffer obuf))))

(defun shell-command-on-region (start end command &optional flag interactive)
  "Execute string COMMAND in inferior shell with region as input.
Normally display output (if any) in temp buffer `*Shell Command Output*';
Prefix arg means replace the region with it.
Noninteractive args are START, END, COMMAND, FLAG.
Noninteractively FLAG means insert output in place of text from START to END,
and put point at the end, but don't alter the mark.

If the output is one line, it is displayed in the echo area,
but it is nonetheless available in buffer `*Shell Command Output*'
even though that buffer is not automatically displayed.  If there is no output
or output is inserted in the current buffer then `*Shell Command Output*' is
deleted." 
746
  (interactive (list (region-beginning) (region-end)
747 748
		     (read-from-minibuffer "Shell command on region: "
					   nil nil nil 'shell-command-history)
Jim Blandy's avatar
Jim Blandy committed
749 750 751 752 753 754 755 756 757 758 759 760 761 762 763
		     current-prefix-arg
		     (prefix-numeric-value current-prefix-arg)))
  (if flag
      ;; Replace specified region with output from command.
      (let ((swap (and interactive (< (point) (mark)))))
	;; Don't muck with mark
	;; unless called interactively.
	(and interactive (push-mark))
	(call-process-region start end shell-file-name t t nil
			     "-c" command)
	(if (get-buffer "*Shell Command Output*")
	    (kill-buffer "*Shell Command Output*"))
	(and interactive swap (exchange-point-and-mark)))
    ;; No prefix argument: put the output in a temp buffer,
    ;; replacing its entire contents.
764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804
    (let ((buffer (get-buffer-create "*Shell Command Output*"))
	  (success nil))
      (unwind-protect
	  (if (eq buffer (current-buffer))
	      ;; If the input is the same buffer as the output,
	      ;; delete everything but the specified region,
	      ;; then replace that region with the output.
	      (progn (delete-region end (point-max))
		     (delete-region (point-min) start)
		     (call-process-region (point-min) (point-max)
					  shell-file-name t t nil
					  "-c" command)
		     (setq success t))
	    ;; Clear the output buffer, then run the command with output there.
	    (save-excursion
	      (set-buffer buffer)
	      (erase-buffer))
	    (call-process-region start end shell-file-name
				 nil buffer nil
				 "-c" command)
	    (setq success t))
	;; Report the amount of output.
	(let ((lines (save-excursion
		       (set-buffer buffer)
		       (if (= (buffer-size) 0)
			   0
			 (count-lines (point-min) (point-max))))))
	  (cond ((= lines 0)
		 (if success
		     (message "(Shell command completed with no output)"))
		 (kill-buffer buffer))
		((and success (= lines 1))
		 (message "%s"
			  (save-excursion
			    (set-buffer buffer)
			    (goto-char (point-min))
			    (buffer-substring (point)
					      (progn (end-of-line) (point)))))
		 (kill-buffer buffer))
		(t 
		 (set-window-start (display-buffer buffer) 1))))))))
Jim Blandy's avatar
Jim Blandy committed
805 806 807 808 809 810 811 812 813

(defun universal-argument ()
  "Begin a numeric argument for the following command.
Digits or minus sign following \\[universal-argument] make up the numeric argument.
\\[universal-argument] following the digits or minus sign ends the argument.
\\[universal-argument] without digits or minus sign provides 4 as argument.
Repeating \\[universal-argument] without digits or minus sign
 multiplies the argument by 4 each time."
  (interactive nil)
Jim Blandy's avatar
Jim Blandy committed
814 815
  (let ((factor 4)
	key)
Jim Blandy's avatar
Jim Blandy committed
816 817
;;    (describe-arg (list factor) 1)
    (setq key (read-key-sequence nil t))
Jim Blandy's avatar
Jim Blandy committed
818 819
    (while (equal (key-binding key) 'universal-argument)
      (setq factor (* 4 factor))
Jim Blandy's avatar
Jim Blandy committed
820 821
;;      (describe-arg (list factor) 1)
      (setq key (read-key-sequence nil t)))
Jim Blandy's avatar
Jim Blandy committed
822 823 824
    (prefix-arg-internal key factor nil)))

(defun prefix-arg-internal (key factor value)
Jim Blandy's avatar
Jim Blandy committed
825 826 827 828 829
  (let ((sign 1))
    (if (and (numberp value) (< value 0))
	(setq sign -1 value (- value)))
    (if (eq value '-)
	(setq sign -1 value nil))
Jim Blandy's avatar
Jim Blandy committed
830
;;    (describe-arg value sign)
Jim Blandy's avatar
Jim Blandy committed
831 832
    (while (equal key "-")
      (setq sign (- sign) factor nil)
Jim Blandy's avatar
Jim Blandy committed
833 834
;;      (describe-arg value sign)
      (setq key (read-key-sequence nil t)))
Jim Blandy's avatar
Jim Blandy committed
835 836
    (while (and (stringp key)
		(= (length key) 1)
Jim Blandy's avatar
Jim Blandy committed
837 838 839 840 841
		(not (string< key "0"))
		(not (string< "9" key)))
      (setq value (+ (* (if (numberp value) value 0) 10)
		     (- (aref key 0) ?0))
	    factor nil)
Jim Blandy's avatar
Jim Blandy committed
842 843
;;      (describe-arg value sign)
      (setq key (read-key-sequence nil t)))
Jim Blandy's avatar
Jim Blandy committed
844
    (setq prefix-arg
Jim Blandy's avatar
Jim Blandy committed
845
	  (cond (factor (list factor))
Jim Blandy's avatar
Jim Blandy committed
846 847
		((numberp value) (* value sign))
		((= sign -1) '-)))
Jim Blandy's avatar
Jim Blandy committed
848 849 850 851 852
    ;; Calling universal-argument after digits
    ;; terminates the argument but is ignored.
    (if (eq (key-binding key) 'universal-argument)
	(progn
	  (describe-arg value sign)
Jim Blandy's avatar
Jim Blandy committed
853
	  (setq key (read-key-sequence nil t))))
854
    (setq unread-command-events (listify-key-sequence key))))
Jim Blandy's avatar
Jim Blandy committed
855 856 857 858 859 860 861 862

(defun describe-arg (value sign)
  (cond ((numberp value)
	 (message "Arg: %d" (* value sign)))
	((consp value)
	 (message "Arg: [%d]" (car value)))
	((< sign 0)
	 (message "Arg: -"))))
Jim Blandy's avatar
Jim Blandy committed
863 864 865 866 867

(defun digit-argument (arg)
  "Part of the numeric argument for the next command.
\\[universal-argument] following digits or minus sign ends the argument."
  (interactive "P")
Jim Blandy's avatar
Jim Blandy committed
868 869
  (prefix-arg-internal (char-to-string (logand last-command-char ?\177))
		       nil arg))
Jim Blandy's avatar
Jim Blandy committed
870 871 872 873 874

(defun negative-argument (arg)
  "Begin a negative numeric argument for the next command.
\\[universal-argument] following digits or minus sign ends the argument."
  (interactive "P")
Jim Blandy's avatar
Jim Blandy committed
875
  (prefix-arg-internal "-" nil arg))
Jim Blandy's avatar
Jim Blandy committed
876 877 878 879 880 881 882 883 884 885 886 887 888

(defun forward-to-indentation (arg)
  "Move forward ARG lines and position at first nonblank character."
  (interactive "p")
  (forward-line arg)
  (skip-chars-forward " \t"))

(defun backward-to-indentation (arg)
  "Move backward ARG lines and position at first nonblank character."
  (interactive "p")
  (forward-line (- arg))
  (skip-chars-forward " \t"))

889
(defvar kill-whole-line nil
890
  "*If non-nil, `kill-line' with no arg at beg of line kills the whole line.")
891

Jim Blandy's avatar
Jim Blandy committed
892
(defun kill-line (&optional arg)
893
  "Kill the rest of the current line; if no nonblanks there, kill thru newline.
Jim Blandy's avatar
Jim Blandy committed
894 895 896 897
With prefix argument, kill that many lines from point.
Negative arguments kill lines backward.

When calling from a program, nil means \"no arg\",
898 899 900 901
a number counts as a prefix arg.

If `kill-whole-line' is non-nil, then kill the whole line
when given no argument at the beginning of a line."
Jim Blandy's avatar
Jim Blandy committed
902 903
  (interactive "P")
  (kill-region (point)
904 905 906
	       ;; Don't shift point before doing the delete; that way,
	       ;; undo will record the right position of point.
	       (save-excursion
Jim Blandy's avatar
Jim Blandy committed
907 908 909 910
		 (if arg
		     (forward-line (prefix-numeric-value arg))
		   (if (eobp)
		       (signal 'end-of-buffer nil))
911
		   (if (or (looking-at "[ \t]*$") (and kill-whole-line (bolp)))
Jim Blandy's avatar
Jim Blandy committed
912 913 914 915
		       (forward-line 1)
		     (end-of-line)))
		 (point))))

Jim Blandy's avatar
Jim Blandy committed
916 917 918 919 920 921
;;;; Window system cut and paste hooks.

(defvar interprogram-cut-function nil
  "Function to call to make a killed region available to other programs.

Most window systems provide some sort of facility for cutting and
922 923 924
pasting text between the windows of different programs.
This variable holds a function that Emacs calls whenever text
is put in the kill ring, to make the new kill available to other
Jim Blandy's avatar
Jim Blandy committed
925 926
programs.

927 928 929 930 931
The function takes one or two arguments.
The first argument, TEXT, is a string containing
the text which should be made available.
The second, PUSH, if non-nil means this is a \"new\" kill;
nil means appending to an \"old\" kill.")
Jim Blandy's avatar
Jim Blandy committed
932 933 934 935 936

(defvar interprogram-paste-function nil
  "Function to call to get text cut from other programs.

Most window systems provide some sort of facility for cutting and
937 938
pasting text between the windows of different programs.
This variable holds a function that Emacs calls to obtain
Jim Blandy's avatar
Jim Blandy committed
939 940 941 942 943
text that other programs have provided for pasting.

The function should be called with no arguments.  If the function
returns nil, then no other program has provided such text, and the top
of the Emacs kill ring should be used.  If the function returns a
Jim Blandy's avatar
Jim Blandy committed
944 945 946 947 948 949 950 951
string, that string should be put in the kill ring as the latest kill.

Note that the function should return a string only if a program other
than Emacs has provided a string for pasting; if Emacs provided the
most recent string, the function should return nil.  If it is
difficult to tell whether Emacs or some other program provided the
current string, it is probably good enough to return nil if the string
is equal (according to `string=') to the last text Emacs provided.")
Jim Blandy's avatar
Jim Blandy committed
952 953 954 955



;;;; The kill ring data structure.
Jim Blandy's avatar
Jim Blandy committed
956 957

(defvar kill-ring nil
Jim Blandy's avatar
Jim Blandy committed
958 959 960 961 962 963 964 965
  "List of killed text sequences.
Since the kill ring is supposed to interact nicely with cut-and-paste
facilities offered by window systems, use of this variable should
interact nicely with `interprogram-cut-function' and
`interprogram-paste-function'.  The functions `kill-new',
`kill-append', and `current-kill' are supposed to implement this
interaction; you may want to use them instead of manipulating the kill
ring directly.")
Jim Blandy's avatar
Jim Blandy committed
966 967 968 969 970 971 972

(defconst kill-ring-max 30
  "*Maximum length of kill ring before oldest elements are thrown away.")

(defvar kill-ring-yank-pointer nil
  "The tail of the kill ring whose car is the last thing yanked.")

Jim Blandy's avatar
Jim Blandy committed
973 974 975 976 977 978 979 980 981
(defun kill-new (string)
  "Make STRING the latest kill in the kill ring.
Set the kill-ring-yank pointer to point to it.
If `interprogram-cut-function' is non-nil, apply it to STRING."
  (setq kill-ring (cons string kill-ring))
  (if (> (length kill-ring) kill-ring-max)
      (setcdr (nthcdr (1- kill-ring-max) kill-ring) nil))
  (setq kill-ring-yank-pointer kill-ring)
  (if interprogram-cut-function
982
      (funcall interprogram-cut-function string t)))
Jim Blandy's avatar
Jim Blandy committed
983

Jim Blandy's avatar
Jim Blandy committed
984
(defun kill-append (string before-p)
Jim Blandy's avatar
Jim Blandy committed
985 986
  "Append STRING to the end of the latest kill in the kill ring.
If BEFORE-P is non-nil, prepend STRING to the kill.
Richard M. Stallman's avatar
Richard M. Stallman committed
987
If `interprogram-cut-function' is set, pass the resulting kill to
Jim Blandy's avatar
Jim Blandy committed
988
it."
Jim Blandy's avatar
Jim Blandy committed
989 990 991
  (setcar kill-ring
	  (if before-p
	      (concat string (car kill-ring))
Jim Blandy's avatar
Jim Blandy committed
992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014
	    (concat (car kill-ring) string)))
  (if interprogram-cut-function
      (funcall interprogram-cut-function (car kill-ring))))

(defun current-kill (n &optional do-not-move)
  "Rotate the yanking point by N places, and then return that kill.
If N is zero, `interprogram-paste-function' is set, and calling it
returns a string, then that string is added to the front of the
kill ring and returned as the latest kill.
If optional arg DO-NOT-MOVE is non-nil, then don't actually move the 
yanking point; just return the Nth kill forward."
  (let ((interprogram-paste (and (= n 0)
				 interprogram-paste-function
				 (funcall interprogram-paste-function))))
    (if interprogram-paste
	(progn
	  ;; Disable the interprogram cut function when we add the new
	  ;; text to the kill ring, so Emacs doesn't try to own the
	  ;; selection, with identical text.
	  (let ((interprogram-cut-function nil))
	    (kill-new interprogram-paste))
	  interprogram-paste)
      (or kill-ring (error "Kill ring is empty"))
1015 1016 1017 1018
      (let ((ARGth-kill-element
	     (nthcdr (mod (- n (length kill-ring-yank-pointer))
			  (length kill-ring))
		     kill-ring)))
Jim Blandy's avatar
Jim Blandy committed
1019 1020 1021
	(or do-not-move
	    (setq kill-ring-yank-pointer ARGth-kill-element))
	(car ARGth-kill-element)))))
Eric S. Raymond's avatar
Eric S. Raymond committed
1022 1023


Jim Blandy's avatar
Jim Blandy committed
1024 1025

;;;; Commands for manipulating the kill ring.
Eric S. Raymond's avatar
Eric S. Raymond committed
1026

Jim Blandy's avatar
Jim Blandy committed
1027 1028 1029 1030 1031
(defun kill-region (beg end)
  "Kill between point and mark.
The text is deleted but saved in the kill ring.
The command \\[yank] can retrieve it from there.
\(If you want to kill and then yank immediately, use \\[copy-region-as-kill].)
1032 1033 1034
If the buffer is read-only, Emacs will beep and refrain from deleting
the text, but put the text in the kill ring anyway.  This means that
you can use the killing commands to copy text from a read-only buffer.
Jim Blandy's avatar
Jim Blandy committed
1035 1036 1037 1038 1039 1040 1041 1042

This is the primitive for programs to kill text (as opposed to deleting it).
Supply two arguments, character numbers indicating the stretch of text
 to be killed.
Any command that calls this function is a \"kill command\".
If the previous command was also a kill command,
the text killed this time appends to the text killed last time
to make one entry in the kill ring."
1043
  (interactive "r")
Jim Blandy's avatar
Jim Blandy committed
1044
  (cond
1045 1046 1047 1048

   ;; If the buffer is read-only, we should beep, in case the person
   ;; just isn't aware of this.  However, there's no harm in putting
   ;; the region's text in the kill ring, anyway.
1049
   ((and buffer-read-only (not inhibit-read-only))
1050
    (copy-region-as-kill beg end)
1051 1052
    ;; This should always barf, and give us the correct error.
    (barf-if-buffer-read-only))
1053 1054 1055

   ;; In certain cases, we can arrange for the undo list and the kill
   ;; ring to share the same string object.  This code does that.
Jim Blandy's avatar
Jim Blandy committed
1056 1057
   ((not (or (eq buffer-undo-list t)
	     (eq last-command 'kill-region)
1058
	     (equal beg end)))
Jim Blandy's avatar
Jim Blandy committed
1059
    ;; Don't let the undo list be truncated before we can even access it.
1060 1061 1062
    (let ((undo-strong-limit (+ (- (max beg end) (min beg end)) 100))
	  (old-list buffer-undo-list)
	  tail)
Jim Blandy's avatar
Jim Blandy committed
1063
      (delete-region beg end)
1064 1065 1066 1067 1068
      ;; Search back in buffer-undo-list for this string,
      ;; in case a change hook made property changes.
      (setq tail buffer-undo-list)
      (while (not (stringp (car (car tail))))
	(setq tail (cdr tail)))
Jim Blandy's avatar
Jim Blandy committed
1069 1070
      ;; Take the same string recorded for undo
      ;; and put it in the kill-ring.
1071
      (kill-new (car (car tail)))
Jim Blandy's avatar
Jim Blandy committed
1072
      (setq this-command 'kill-region)))
1073

Jim Blandy's avatar
Jim Blandy committed
1074
   (t
Jim Blandy's avatar
Jim Blandy committed
1075
    (copy-region-as-kill beg end)
Jim Blandy's avatar
Jim Blandy committed
1076
    (delete-region beg end))))
Jim Blandy's avatar
Jim Blandy committed
1077 1078 1079

(defun copy-region-as-kill (beg end)
  "Save the region as if killed, but don't kill it.
Jim Blandy's avatar
Jim Blandy committed
1080 1081
If `interprogram-cut-function' is non-nil, also save the text for a window
system cut and paste."
Jim Blandy's avatar
Jim Blandy committed
1082 1083 1084
  (interactive "r")
  (if (eq last-command 'kill-region)
      (kill-append (buffer-substring beg end) (< end beg))
Jim Blandy's avatar
Jim Blandy committed
1085 1086
    (kill-new (buffer-substring beg end)))
  (setq this-command 'kill-region)
Jim Blandy's avatar
Jim Blandy committed
1087 1088 1089
  nil)

(defun kill-ring-save (beg end)
1090
  "Save the region as if killed, but don't kill it.
1091
This command is similar to `copy-region-as-kill', except that it gives
1092 1093 1094
visual feedback indicating the extent of the region being copied.
If `interprogram-cut-function' is non-nil, also save the text for a window
system cut and paste."
Jim Blandy's avatar
Jim Blandy committed
1095 1096
  (interactive "r")
  (copy-region-as-kill beg end)
Eric S. Raymond's avatar
Eric S. Raymond committed
1097
  (if (interactive-p)
1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113
      (let ((other-end (if (= (point) beg) end beg))
	    (opoint (point))
	    ;; Inhibit quitting so we can make a quit here
	    ;; look like a C-g typed as a command.
	    (inhibit-quit t))
	(if (pos-visible-in-window-p other-end (selected-window))
	    (progn
	      ;; Swap point and mark.
	      (set-marker (mark-marker) (point) (current-buffer))
	      (goto-char other-end)
	      (sit-for 1)
	      ;; Swap back.
	      (set-marker (mark-marker) other-end (current-buffer))
	      (goto-char opoint)
	      ;; If user quit, deactivate the mark
	      ;; as C-g would as a command.
1114
	      (and quit-flag mark-active
1115
		   (deactivate-mark)))
1116 1117 1118 1119 1120 1121 1122 1123
	  (let* ((killed-text (current-kill 0))
		 (message-len (min (length killed-text) 40)))
	    (if (= (point) beg)
		;; Don't say "killed"; that is misleading.
		(message "Saved text until \"%s\""
			(substring killed-text (- message-len)))
	      (message "Saved text from \"%s\""
		      (substring killed-text 0 message-len))))))))
Jim Blandy's avatar
Jim Blandy committed
1124 1125

(defun append-next-kill ()
1126
  "Cause following command, if it kills, to append to previous kill."
Jim Blandy's avatar
Jim Blandy committed
1127 1128 1129 1130 1131 1132 1133 1134
  (interactive)
  (if (interactive-p)
      (progn
	(setq this-command 'kill-region)
	(message "If the next command is a kill, it will append"))
    (setq last-command 'kill-region)))

(defun yank-pop (arg)
1135 1136
  "Replace just-yanked stretch of killed text with a different stretch.
This command is allowed only immediately after a `yank' or a `yank-pop'.
Jim Blandy's avatar
Jim Blandy committed
1137
At such a time, the region contains a stretch of reinserted
1138
previously-killed text.  `yank-pop' deletes that text and inserts in its
Jim Blandy's avatar
Jim Blandy committed
1139 1140 1141
place a different stretch of killed text.

With no argument, the previous kill is inserted.
1142 1143
With argument N, insert the Nth previous kill.
If N is negative, this is a more recent kill.
Jim Blandy's avatar
Jim Blandy committed
1144 1145 1146 1147 1148 1149 1150

The sequence of kills wraps around, so that after the oldest one
comes the newest one."
  (interactive "*p")
  (if (not (eq last-command 'yank))
      (error "Previous command was not a yank"))
  (setq this-command 'yank)
1151 1152
  (let ((before (< (point) (mark t))))
    (delete-region (point) (mark t))
1153
    (set-marker (mark-marker) (point) (current-buffer))
Jim Blandy's avatar
Jim Blandy committed
1154
    (insert (current-kill arg))
1155 1156 1157 1158 1159 1160
    (if before
	;; This is like exchange-point-and-mark, but doesn't activate the mark.
	;; It is cleaner to avoid activation, even though the command
	;; loop would deactivate the mark because we inserted text.
	(goto-char (prog1 (mark t)
		     (set-marker (mark-marker) (point) (current-buffer))))))
1161
  nil)
Jim Blandy's avatar
Jim Blandy committed
1162 1163 1164 1165

(defun yank (&optional arg)
  "Reinsert the last stretch of killed text.
More precisely, reinsert the stretch of killed text most recently
1166 1167 1168
killed OR yanked.  Put point at end, and set mark at beginning.
With just C-u as argument, same but put point at beginning (and mark at end).
With argument N, reinsert the Nth most recently killed stretch of killed
Jim Blandy's avatar
Jim Blandy committed
1169 1170 1171
text.
See also the command \\[yank-pop]."
  (interactive "*P")
1172 1173 1174
  ;; If we don't get all the way thru, make last-command indicate that
  ;; for the following command.
  (setq this-command t)
Jim Blandy's avatar
Jim Blandy committed
1175
  (push-mark (point))
Jim Blandy's avatar
Jim Blandy committed
1176 1177 1178 1179
  (insert (current-kill (cond
			 ((listp arg) 0)
			 ((eq arg '-) -1)
			 (t (1- arg)))))
Jim Blandy's avatar
Jim Blandy committed
1180
  (if (consp arg)
1181 1182 1183 1184 1185
      ;; This is like exchange-point-and-mark, but doesn't activate the mark.
      ;; It is cleaner to avoid activation, even though the command
      ;; loop would deactivate the mark because we inserted text.
      (goto-char (prog1 (mark t)
		   (set-marker (mark-marker) (point) (current-buffer)))))
1186 1187
  ;; If we do get all the way thru, make this-command indicate that.
  (setq this-command 'yank)
1188
  nil)
Jim Blandy's avatar
Jim Blandy committed
1189 1190 1191 1192 1193 1194 1195

(defun rotate-yank-pointer (arg)
  "Rotate the yanking point in the kill ring.
With argument, rotate that many kills forward (or backward, if negative)."
  (interactive "p")
  (current-kill arg))

Jim Blandy's avatar
Jim Blandy committed
1196 1197 1198 1199 1200

(defun insert-buffer (buffer)
  "Insert after point the contents of BUFFER.
Puts mark after the inserted text.
BUFFER may be a buffer or a buffer name."
1201 1202
  (interactive (list (progn (barf-if-buffer-read-only)
			    (read-buffer "Insert buffer: " (other-buffer) t))))
Jim Blandy's avatar
Jim Blandy committed
1203 1204 1205 1206 1207 1208 1209 1210 1211
  (or (bufferp buffer)
      (setq buffer (get-buffer buffer)))
  (let (start end newmark)
    (save-excursion
      (save-excursion
	(set-buffer buffer)
	(setq start (point-min) end (point-max)))
      (insert-buffer-substring buffer start end)
      (setq newmark (point)))
1212 1213
    (push-mark newmark))
  nil)
Jim Blandy's avatar
Jim Blandy committed
1214 1215 1216 1217 1218 1219 1220 1221

(defun append-to-buffer (buffer start end)
  "Append to specified buffer the text of the region.
It is inserted into that buffer before its point.

When calling from a program, give three arguments:
BUFFER (or buffer name), START and END.
START and END specify the portion of the current buffer to be copied."
Jim Blandy's avatar
Jim Blandy committed
1222
  (interactive
1223 1224
   (list (read-buffer "Append to buffer: " (other-buffer nil t))
	 (region-beginning) (region-end)))
Jim Blandy's avatar
Jim Blandy committed
1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258
  (let ((oldbuf (current-buffer)))
    (save-excursion
      (set-buffer (get-buffer-create buffer))
      (insert-buffer-substring oldbuf start end))))

(defun prepend-to-buffer (buffer start end)
  "Prepend to specified buffer the text of the region.
It is inserted into that buffer after its point.

When calling from a program, give three arguments:
BUFFER (or buffer name), START and END.
START and END specify the portion of the current buffer to be copied."
  (interactive "BPrepend to buffer: \nr")
  (let ((oldbuf (current-buffer)))
    (save-excursion
      (set-buffer (get-buffer-create buffer))
      (save-excursion
	(insert-buffer-substring oldbuf start end)))))

(defun copy-to-buffer (buffer start end)
  "Copy to specified buffer the text of the region.
It is inserted into that buffer, replacing existing text there.

When calling from a program, give three arguments:
BUFFER (or buffer name), START and END.
START and END specify the portion of the current buffer to be copied."
  (interactive "BCopy to buffer: \nr")
  (let ((oldbuf (current-buffer)))
    (save-excursion
      (set-buffer (get-buffer-create buffer))
      (erase-buffer)
      (save-excursion
	(insert-buffer-substring oldbuf start end)))))

1259 1260 1261 1262 1263 1264 1265
(defvar mark-even-if-inactive nil
  "*Non-nil means you can use the mark even when inactive.
This option makes a difference in Transient Mark mode.
When the option is non-nil, deactivation of the mark
turns off region highlighting, but commands that use the mark
behave as if the mark were still active.")

1266 1267 1268
(put 'mark-inactive 'error-conditions '(mark-inactive error))
(put 'mark-inactive 'error-message "The mark is not active now")

1269
(defun mark (&optional force)
Richard M. Stallman's avatar
Richard M. Stallman committed
1270
  "Return this buffer's mark value as integer; error if mark inactive.
1271
If optional argument FORCE is non-nil, access the mark value
Richard M. Stallman's avatar
Richard M. Stallman committed
1272 1273
even if the mark is not currently active, and return nil
if there is no mark at all.
1274

Jim Blandy's avatar
Jim Blandy committed
1275 1276
If you are using this in an editing command, you are most likely making
a mistake; see the documentation of `set-mark'."
1277
  (if (or force mark-active mark-even-if-inactive)
1278
      (marker-position (mark-marker))
1279
    (signal 'mark-inactive nil)))
Jim Blandy's avatar
Jim Blandy committed
1280

1281 1282 1283 1284
;; Many places set mark-active directly, and several of them failed to also
;; run deactivate-mark-hook.  This shorthand should simplify.
(defsubst deactivate-mark ()
  "Deactivate the mark by setting `mark-active' to nil.
1285
\(That makes a difference only in Transient Mark mode.)
1286 1287 1288 1289
Also runs the hook `deactivate-mark-hook'."
  (setq mark-active nil)
  (run-hooks 'deactivate-mark-hook))

Jim Blandy's avatar
Jim Blandy committed
1290 1291 1292 1293 1294 1295 1296 1297 1298
(defun set-mark (pos)
  "Set this buffer's mark to POS.  Don't use this function!
That is to say, don't use this function unless you want
the user to see that the mark has moved, and you want the previous
mark position to be lost.

Normally, when a new mark is set, the old one should go on the stack.
This is why most applications should use push-mark, not set-mark.

1299
Novice Emacs Lisp programmers often try to use the mark for the wrong
Jim Blandy's avatar
Jim Blandy committed
1300 1301 1302 1303 1304 1305 1306
purposes.  The mark saves a location for the user's convenience.
Most editing commands should not alter the mark.
To remember a location for internal use in the Lisp program,
store it in a Lisp variable.  Example:

   (let ((beg (point))) (forward-line 1) (delete-region beg (point)))."

1307 1308 1309 1310 1311 1312 1313
  (if pos
      (progn
	(setq mark-active t)
	(run-hooks 'activate-mark-hook)
	(set-marker (mark-marker) pos (current-buffer)))
    (deactivate-mark)
    (set-marker (mark-marker) pos (current-buffer))))
Jim Blandy's avatar
Jim Blandy committed
1314 1315 1316 1317 1318 1319 1320 1321 1322

(defvar mark-ring nil
  "The list of saved former marks of the current buffer,
most recent first.")
(make-variable-buffer-local 'mark-ring)

(defconst mark-ring-max 16
  "*Maximum size of mark ring.  Start discarding off end if gets this big.")

1323 1324 1325 1326 1327 1328 1329
(defvar global-mark-ring nil
  "The list of saved global marks, most recent first.")

(defconst global-mark-ring-max 16
  "*Maximum size of global mark ring.  \
Start discarding off end if gets this big.")

Jim Blandy's avatar
Jim Blandy committed
1330 1331
(defun set-mark-command (arg)
  "Set mark at where point is, or jump to mark.
1332 1333 1334 1335
With no prefix argument, set mark, push old mark position on local mark
ring, and push mark on global mark ring.
With argument, jump to mark, and pop a new position for mark off the ring
\(does not affect global mark ring\).
Jim Blandy's avatar
Jim Blandy committed
1336

1337
Novice Emacs Lisp programmers often try to use the mark for the wrong
Jim Blandy's avatar
Jim Blandy committed
1338 1339 1340
purposes.  See the documentation of `set-mark' for more information."
  (interactive "P")
  (if (null arg)
1341
      (progn
1342
	(push-mark nil nil t))
1343
    (if (null (mark t))
Jim Blandy's avatar
Jim Blandy committed
1344
	(error "No mark set in this buffer")
1345
      (goto-char (mark t))
Jim Blandy's avatar
Jim Blandy committed
1346 1347
      (pop-mark))))