simple.el 75 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 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 44 45 46
    ;; 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.
	  (if (and buffer-undo-list (not (eq buffer-undo-list t)))
	      (setq buffer-undo-list (cons (point) buffer-undo-list)))
	  (forward-char -1)))
Jim Blandy's avatar
Jim Blandy committed
47 48
    (while (> arg 0)
      (save-excursion
49 50
        (insert ?\n))
      (if do-fill-prefix (insert fill-prefix))
Jim Blandy's avatar
Jim Blandy committed
51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
      (setq arg (1- arg)))
    (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.
66
This is useful for inserting control characters.
Jim Blandy's avatar
Jim Blandy committed
67
You may also type up to 3 octal digits, to insert a character with that code.
68 69 70 71 72 73 74 75 76

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
77
  (interactive "*p")
78 79 80 81 82 83
  (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))
84
    (insert-char char arg)))
Jim Blandy's avatar
Jim Blandy committed
85 86 87

(defun delete-indentation (&optional arg)
  "Join this line to previous and fix up whitespace at join.
88
If there is a fill prefix, delete it from the beginning of this line.
Jim Blandy's avatar
Jim Blandy committed
89 90 91 92 93 94 95
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)))
96 97 98
	;; If the second line started with the fill prefix,
	;; delete the prefix.
	(if (and fill-prefix
99
		 (<= (+ (point) (length fill-prefix)) (point-max))
100 101 102 103
		 (string= fill-prefix
			  (buffer-substring (point)
					    (+ (point) (length fill-prefix)))))
	    (delete-region (point) (+ (point) (length fill-prefix))))
Jim Blandy's avatar
Jim Blandy committed
104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141
	(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]*$"))
Jim Blandy's avatar
Jim Blandy committed
142
      ;; Set singleblank if there is just one blank line here.
Jim Blandy's avatar
Jim Blandy committed
143 144 145 146 147 148
      (setq singleblank
	    (and thisblank
		 (not (looking-at "[ \t]*\n[ \t]*$"))
		 (or (bobp)
		     (progn (forward-line -1)
			    (not (looking-at "[ \t]*$")))))))
Jim Blandy's avatar
Jim Blandy committed
149
    ;; Delete preceding blank lines, and this one too if it's the only one.
Jim Blandy's avatar
Jim Blandy committed
150 151 152 153 154 155 156 157
    (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
158 159
    ;; Delete following blank lines, unless the current line is blank
    ;; and there are no following blank lines.
Jim Blandy's avatar
Jim Blandy committed
160 161 162 163 164 165 166
    (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
167 168 169 170 171
			   (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
172 173 174 175 176 177 178 179 180

(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.
181
Indentation is done using the value of `indent-line-function'.
Jim Blandy's avatar
Jim Blandy committed
182
In programming language modes, this is the same as TAB.
183 184
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
185 186
  (interactive "*")
  (delete-region (point) (progn (skip-chars-backward " \t") (point)))
Jim Blandy's avatar
Jim Blandy committed
187
  (newline)
Jim Blandy's avatar
Jim Blandy committed
188 189 190 191 192
  (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,
193
which means calling the current value of `indent-line-function'.
Jim Blandy's avatar
Jim Blandy committed
194 195
In programming language modes, this is the same as TAB.
In some text modes, where TAB inserts a tab, this indents to the
196
column specified by the variable `left-margin'."
Jim Blandy's avatar
Jim Blandy committed
197 198 199 200
  (interactive "*")
  (save-excursion
    (delete-region (point) (progn (skip-chars-backward " \t") (point)))
    (indent-according-to-mode))
Jim Blandy's avatar
Jim Blandy committed
201
  (newline)
Jim Blandy's avatar
Jim Blandy committed
202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238
  (indent-according-to-mode))

(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.
239 240

Don't use this command in Lisp programs!
Jim Blandy's avatar
Jim Blandy committed
241 242 243 244 245 246 247 248 249 250 251 252 253 254 255
\(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.
256 257

Don't use this command in Lisp programs!
Jim Blandy's avatar
Jim Blandy committed
258 259 260 261 262 263 264 265 266 267 268
\(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
269 270
  ;; 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
271
  (if arg (forward-line 1)
Eric S. Raymond's avatar
Eric S. Raymond committed
272 273 274 275 276 277 278 279
    ;; 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
280 281

(defun mark-whole-buffer ()
Jim Blandy's avatar
Jim Blandy committed
282 283 284 285
  "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
286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309
  (interactive)
  (push-mark (point))
  (push-mark (point-max))
  (goto-char (point-min)))

(defun count-lines-region (start end)
  "Print number of lines and charcters in the region."
  (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,
310
but can be one more if START is not equal to END
Jim Blandy's avatar
Jim Blandy committed
311
and the greater of them is not at the start of a line."
312 313 314 315 316 317 318 319 320 321 322 323 324
  (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)))
	      done)
	  (- (buffer-size) (forward-line (buffer-size))))))))
Jim Blandy's avatar
Jim Blandy committed
325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359

(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))

360 361 362 363
(defvar read-expression-map (copy-keymap minibuffer-local-map)
  "Minibuffer keymap used for reading Lisp expressions.")
(define-key read-expression-map "\M-\t" 'lisp-complete-symbol)

Jim Blandy's avatar
Jim Blandy committed
364 365 366 367 368 369
(put 'eval-expression 'disabled t)

;; We define this, rather than making  eval  interactive,
;; for the sake of completion of names like eval-region, eval-current-buffer.
(defun eval-expression (expression)
  "Evaluate EXPRESSION and print value in minibuffer.
370
Value is also consed on to front of the variable `values'."
371 372
  (interactive (list (read-from-minibuffer "Eval: "
					   nil read-expression-map t)))
Jim Blandy's avatar
Jim Blandy committed
373 374 375 376 377 378 379
  (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."
380 381 382
  (let ((command (read-from-minibuffer prompt
				       (prin1-to-string command)
				       read-expression-map t)))
Jim Blandy's avatar
Jim Blandy committed
383 384 385 386 387
    ;; Add edited command to command history, unless redundant.
    (or (equal command (car command-history))
	(setq command-history (cons command command-history)))
    (eval command)))

388
(defun repeat-complex-command (arg)
Jim Blandy's avatar
Jim Blandy committed
389 390 391 392 393 394
  "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.
395 396
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
397
  (interactive "p")
398
  (let ((elt (nth (1- arg) command-history))
399
	(minibuffer-history-position arg)
400
	(minibuffer-history-sexp-flag t)
Jim Blandy's avatar
Jim Blandy committed
401 402
	newcmd)
    (if elt
403
	(progn
Jim Blandy's avatar
Jim Blandy committed
404 405
	  (setq newcmd (read-from-minibuffer "Redo: "
					     (prin1-to-string elt)
406
					     read-expression-map
407 408 409
					     t
					     (cons 'command-history
						   arg)))
410 411 412 413
	  ;; 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)))
Jim Blandy's avatar
Jim Blandy committed
414 415 416 417 418 419
	  ;; 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)))
	  (eval newcmd))
      (ding))))
420

421 422 423 424 425 426 427 428
(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.")
429 430
(setq minibuffer-history-variable 'minibuffer-history)
(setq minibuffer-history-position nil)
431
(defvar minibuffer-history-search-history nil)
432

Jim Blandy's avatar
Jim Blandy committed
433
(mapcar
434 435 436 437 438 439 440 441 442 443
 (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)
444 445 446 447
	      ;; (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
448
		  (progn (error "EMACS BUG!") (cdr command))
449 450 451 452 453 454 455
		(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))))
456 457 458 459
 '(("\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
460 461
   ("\er" . previous-matching-history-element)
   ("\es" . next-matching-history-element)))
462 463

(defun previous-matching-history-element (regexp n)
464 465 466 467 468 469 470 471 472 473 474 475 476
  "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
   (let ((enable-recursive-minibuffers t)
	 (minibuffer-history-sexp-flag nil))
     (list (read-from-minibuffer "Previous element matching (regexp): "
				 nil
				 minibuffer-local-map
				 nil
				 'minibuffer-history-search-history)
	   (prefix-numeric-value current-prefix-arg))))
477
  (let ((history (symbol-value minibuffer-history-variable))
478
	prevpos
479 480 481 482 483 484
	(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)
485 486
		     "No later matching history item"
		   "No earlier matching history item")))
487 488 489 490
      (if (string-match regexp
			(if minibuffer-history-sexp-flag
			    (prin1-to-string (nth (1- pos) history))
			  (nth (1- pos) history)))
491
	  (setq n (+ n (if (< n 0) 1 -1)))))
492 493 494 495 496 497
    (setq minibuffer-history-position pos)
    (erase-buffer)
    (let ((elt (nth (1- pos) history)))
      (insert (if minibuffer-history-sexp-flag
		  (prin1-to-string elt)
		elt)))
498 499 500 501
      (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))))
502 503

(defun next-matching-history-element (regexp n)
504 505 506 507 508 509 510 511 512 513 514 515 516
  "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
   (let ((enable-recursive-minibuffers t)
	 (minibuffer-history-sexp-flag nil))
     (list (read-from-minibuffer "Next element matching (regexp): "
				 nil
				 minibuffer-local-map
				 nil
				 'minibuffer-history-search-history)
	   (prefix-numeric-value current-prefix-arg))))
517
  (previous-matching-history-element regexp (- n)))
Jim Blandy's avatar
Jim Blandy committed
518

519 520
(defun next-history-element (n)
  "Insert the next element of the minibuffer history into the minibuffer."
Jim Blandy's avatar
Jim Blandy committed
521
  (interactive "p")
522 523 524 525
  (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)
526 527
		   "End of history; no next item"
		 "Beginning of history; no preceding item"))
Jim Blandy's avatar
Jim Blandy committed
528
      (erase-buffer)
529
      (setq minibuffer-history-position narg)
530 531 532 533 534
      (let ((elt (nth (1- minibuffer-history-position)
		      (symbol-value minibuffer-history-variable))))
	(insert
	 (if minibuffer-history-sexp-flag
	     (prin1-to-string elt)
535
	   elt)))
Jim Blandy's avatar
Jim Blandy committed
536 537
      (goto-char (point-min)))))

538
(defun previous-history-element (n)
Richard M. Stallman's avatar
Richard M. Stallman committed
539
  "Inserts the previous element of the minibuffer history into the minibuffer."
Jim Blandy's avatar
Jim Blandy committed
540
  (interactive "p")
541
  (next-history-element (- n)))
542 543 544 545 546

(defun next-complete-history-element (n)
  "\
Get previous element of history which is a completion of minibuffer contents."
  (interactive "p")
547 548 549 550 551 552 553
  (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)))
554 555 556 557 558

(defun previous-complete-history-element (n)
  "Get next element of history which is a completion of minibuffer contents."
  (interactive "p")
  (next-complete-history-element (- n)))
559

Jim Blandy's avatar
Jim Blandy committed
560 561 562 563 564 565 566 567 568 569 570
(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
571
(defalias 'advertised-undo 'undo)
Jim Blandy's avatar
Jim Blandy committed
572 573 574 575 576 577 578

(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")
  (let ((modified (buffer-modified-p)))
Jim Blandy's avatar
Jim Blandy committed
579 580
    (or (eq (selected-window) (minibuffer-window))
	(message "Undo!"))
Jim Blandy's avatar
Jim Blandy committed
581 582 583 584 585 586 587 588 589
    (or (eq last-command 'undo)
	(progn (undo-start)
	       (undo-more 1)))
    (setq this-command 'undo)
    (undo-more (or arg 1))
    (and modified (not (buffer-modified-p))
	 (delete-auto-save-file-if-necessary))))

(defun undo-start ()
590 591
  "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
592 593 594 595 596 597
  (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.
598 599
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
600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702
  (or pending-undo-list
      (error "No further undo information"))
  (setq pending-undo-list (primitive-undo count pending-undo-list)))

(defvar last-shell-command "")
(defvar last-shell-command-on-region "")

(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."
  (interactive (list (read-string "Shell command: " last-shell-command)
		     current-prefix-arg))
  (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 ($?prompt) exit" before things which are not useful
	     ;; non-interactively.  Besides, if someone wants their other
	     ;; aliases for shell commands then they can still have them.
	     (call-process shell-file-name nil t nil
			   "-c" command)
	     (exchange-point-and-mark))
    ;; Preserve the match data in case called from a program.
    (let ((data (match-data)))
      (unwind-protect
	  (if (string-match "[ \t]*&[ \t]*$" 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." 
703
  (interactive (list (region-beginning) (region-end)
Jim Blandy's avatar
Jim Blandy committed
704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764
		     (read-string "Shell command on region: "
				  last-shell-command-on-region)
		     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.
    (let ((buffer (get-buffer-create "*Shell Command Output*")))
      (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))
	;; 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))
      ;; 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)
	       (message "(Shell command completed with no output)")
	       (kill-buffer "*Shell Command Output*"))
	      ((= lines 1)
	       (message "%s"
			(save-excursion
			  (set-buffer buffer)
			  (goto-char (point-min))
			  (buffer-substring (point)
					    (progn (end-of-line) (point))))))
	      (t 
	       (set-window-start (display-buffer buffer) 1)))))))

(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
765 766
  (let ((factor 4)
	key)
Jim Blandy's avatar
Jim Blandy committed
767 768
;;    (describe-arg (list factor) 1)
    (setq key (read-key-sequence nil t))
Jim Blandy's avatar
Jim Blandy committed
769 770
    (while (equal (key-binding key) 'universal-argument)
      (setq factor (* 4 factor))
Jim Blandy's avatar
Jim Blandy committed
771 772
;;      (describe-arg (list factor) 1)
      (setq key (read-key-sequence nil t)))
Jim Blandy's avatar
Jim Blandy committed
773 774 775
    (prefix-arg-internal key factor nil)))

(defun prefix-arg-internal (key factor value)
Jim Blandy's avatar
Jim Blandy committed
776 777 778 779 780
  (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
781
;;    (describe-arg value sign)
Jim Blandy's avatar
Jim Blandy committed
782 783
    (while (equal key "-")
      (setq sign (- sign) factor nil)
Jim Blandy's avatar
Jim Blandy committed
784 785
;;      (describe-arg value sign)
      (setq key (read-key-sequence nil t)))
Jim Blandy's avatar
Jim Blandy committed
786 787
    (while (and (stringp key)
		(= (length key) 1)
Jim Blandy's avatar
Jim Blandy committed
788 789 790 791 792
		(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
793 794
;;      (describe-arg value sign)
      (setq key (read-key-sequence nil t)))
Jim Blandy's avatar
Jim Blandy committed
795
    (setq prefix-arg
Jim Blandy's avatar
Jim Blandy committed
796
	  (cond (factor (list factor))
Jim Blandy's avatar
Jim Blandy committed
797 798
		((numberp value) (* value sign))
		((= sign -1) '-)))
Jim Blandy's avatar
Jim Blandy committed
799 800 801 802 803
    ;; 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
804
	  (setq key (read-key-sequence nil t))))
805
    (setq unread-command-events (listify-key-sequence key))))
Jim Blandy's avatar
Jim Blandy committed
806 807 808 809 810 811 812 813

(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
814 815 816 817 818

(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
819 820
  (prefix-arg-internal (char-to-string (logand last-command-char ?\177))
		       nil arg))
Jim Blandy's avatar
Jim Blandy committed
821 822 823 824 825

(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
826
  (prefix-arg-internal "-" nil arg))
Jim Blandy's avatar
Jim Blandy committed
827 828 829 830 831 832 833 834 835 836 837 838 839

(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"))

840 841 842 843
(defvar kill-whole-line nil
  "*If non-nil, kill-line kills the whole line (including the newline)
 if point is positioned at the beginning of a line.")

Jim Blandy's avatar
Jim Blandy committed
844
(defun kill-line (&optional arg)
845 846
  "Kill the rest of the current line; if the line is blank, or if point is at
the beginning of the line and kill-whole-line is non-nil, kill thru newline.
Jim Blandy's avatar
Jim Blandy committed
847 848 849 850 851 852 853
With prefix argument, kill that many lines from point.
Negative arguments kill lines backward.

When calling from a program, nil means \"no arg\",
a number counts as a prefix arg."
  (interactive "P")
  (kill-region (point)
854 855 856
	       ;; 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
857 858 859 860
		 (if arg
		     (forward-line (prefix-numeric-value arg))
		   (if (eobp)
		       (signal 'end-of-buffer nil))
861
		   (if (or (looking-at "[ \t]*$") (and kill-whole-line (bolp)))
Jim Blandy's avatar
Jim Blandy committed
862 863 864 865
		       (forward-line 1)
		     (end-of-line)))
		 (point))))

Jim Blandy's avatar
Jim Blandy committed
866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890
;;;; 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
pasting text between the windows of different programs.  On startup,
this variable is set to a function which emacs will call whenever text
is put in the kill ring to make the new kill available to other
programs.

The function takes one argument, TEXT, which is a string containing
the text which should be made available.")

(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
pasting text between the windows of different programs.  On startup,
this variable is set to a function which emacs will call to obtain
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
891 892 893 894 895 896 897 898
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
899 900 901 902



;;;; The kill ring data structure.
Jim Blandy's avatar
Jim Blandy committed
903 904

(defvar kill-ring nil
Jim Blandy's avatar
Jim Blandy committed
905 906 907 908 909 910 911 912
  "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
913 914 915 916 917 918 919

(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
920 921 922 923 924 925 926 927 928 929 930
(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
      (funcall interprogram-cut-function string)))

Jim Blandy's avatar
Jim Blandy committed
931
(defun kill-append (string before-p)
Jim Blandy's avatar
Jim Blandy committed
932 933
  "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
934
If `interprogram-cut-function' is set, pass the resulting kill to
Jim Blandy's avatar
Jim Blandy committed
935
it."
Jim Blandy's avatar
Jim Blandy committed
936 937 938
  (setcar kill-ring
	  (if before-p
	      (concat string (car kill-ring))
Jim Blandy's avatar
Jim Blandy committed
939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969
	    (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"))
      (let* ((length (length kill-ring))
	     (ARGth-kill-element
	      (nthcdr (% (+ n (- length (length kill-ring-yank-pointer)))
			 length)
		      kill-ring)))
	(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
970 971


Jim Blandy's avatar
Jim Blandy committed
972 973

;;;; Commands for manipulating the kill ring.
Eric S. Raymond's avatar
Eric S. Raymond committed
974

Jim Blandy's avatar
Jim Blandy committed
975 976 977 978 979
(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].)
980 981 982
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
983 984 985 986 987 988 989 990

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."
991
  (interactive "r")
Jim Blandy's avatar
Jim Blandy committed
992
  (cond
993 994 995 996 997 998

   ;; 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.
   (buffer-read-only
    (copy-region-as-kill beg end)
999 1000
    ;; This should always barf, and give us the correct error.
    (barf-if-buffer-read-only))
1001 1002 1003

   ;; 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
1004 1005 1006 1007
   ((not (or (eq buffer-undo-list t)
	     (eq last-command 'kill-region)
	     (eq beg end)))
    ;; Don't let the undo list be truncated before we can even access it.
Jim Blandy's avatar
Jim Blandy committed
1008
    (let ((undo-strong-limit (+ (- (max beg end) (min beg end)) 100)))
Jim Blandy's avatar
Jim Blandy committed
1009 1010 1011 1012 1013
      (delete-region beg end)
      ;; Take the same string recorded for undo
      ;; and put it in the kill-ring.
      (kill-new (car (car buffer-undo-list)))
      (setq this-command 'kill-region)))
1014

Jim Blandy's avatar
Jim Blandy committed
1015
   (t
Jim Blandy's avatar
Jim Blandy committed
1016
    (copy-region-as-kill beg end)
Jim Blandy's avatar
Jim Blandy committed
1017
    (delete-region beg end))))
Jim Blandy's avatar
Jim Blandy committed
1018 1019 1020

(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
1021 1022
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
1023 1024 1025
  (interactive "r")
  (if (eq last-command 'kill-region)
      (kill-append (buffer-substring beg end) (< end beg))
Jim Blandy's avatar
Jim Blandy committed
1026 1027
    (kill-new (buffer-substring beg end)))
  (setq this-command 'kill-region)
Jim Blandy's avatar
Jim Blandy committed
1028 1029 1030
  nil)

(defun kill-ring-save (beg end)
1031 1032 1033 1034 1035
  "Save the region as if killed, but don't kill it.
This command is similar to copy-region-as-kill, except that it gives
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
1036 1037
  (interactive "r")
  (copy-region-as-kill beg end)
Eric S. Raymond's avatar
Eric S. Raymond committed
1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052
  (if (interactive-p)
      (save-excursion
	(let ((other-end (if (= (point) beg) end beg)))
	  (if (pos-visible-in-window-p other-end (selected-window))
	      (progn
		(goto-char other-end)
		(sit-for 1))
	    (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
1053 1054

(defun append-next-kill ()
1055
  "Cause following command, if it kills, to append to previous kill."
Jim Blandy's avatar
Jim Blandy committed
1056 1057 1058 1059 1060 1061 1062 1063
  (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)
1064 1065
  "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
1066
At such a time, the region contains a stretch of reinserted
1067
previously-killed text.  `yank-pop' deletes that text and inserts in its
Jim Blandy's avatar
Jim Blandy committed
1068 1069 1070
place a different stretch of killed text.

With no argument, the previous kill is inserted.
1071 1072
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
1073 1074 1075 1076 1077 1078 1079 1080 1081 1082

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)
  (let ((before (< (point) (mark))))
    (delete-region (point) (mark))
    (set-mark (point))
Jim Blandy's avatar
Jim Blandy committed
1083
    (insert (current-kill arg))
1084 1085
    (if before (exchange-point-and-mark)))
  nil)
Jim Blandy's avatar
Jim Blandy committed
1086 1087 1088 1089

(defun yank (&optional arg)
  "Reinsert the last stretch of killed text.
More precisely, reinsert the stretch of killed text most recently
1090 1091 1092
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
1093 1094 1095 1096
text.
See also the command \\[yank-pop]."
  (interactive "*P")
  (push-mark (point))
Jim Blandy's avatar
Jim Blandy committed
1097 1098 1099 1100
  (insert (current-kill (cond
			 ((listp arg) 0)
			 ((eq arg '-) -1)
			 (t (1- arg)))))
Jim Blandy's avatar
Jim Blandy committed
1101
  (if (consp arg)
1102 1103
      (exchange-point-and-mark))
  nil)
Jim Blandy's avatar
Jim Blandy committed
1104 1105 1106 1107 1108 1109 1110

(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
1111 1112 1113 1114 1115

(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."
1116 1117
  (interactive (list (progn (barf-if-buffer-read-only)
			    (read-buffer "Insert buffer: " (other-buffer) t))))
Jim Blandy's avatar
Jim Blandy committed
1118 1119 1120 1121 1122 1123 1124 1125 1126
  (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)))
1127 1128
    (push-mark newmark))
  nil)
Jim Blandy's avatar
Jim Blandy committed
1129 1130 1131 1132 1133 1134 1135 1136

(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
1137 1138
  (interactive
   (list (read-buffer "Append to buffer: " (other-buffer nil t) t)))
Jim Blandy's avatar
Jim Blandy committed
1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172
  (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)))))

1173 1174 1175 1176 1177
(defun mark (&optional force)
  "Return this buffer's mark value as integer, or nil if no active mark now.
If optional argument FORCE is non-nil, access the mark value
even if the mark is not currently active.

Jim Blandy's avatar
Jim Blandy committed
1178 1179
If you are using this in an editing command, you are most likely making
a mistake; see the documentation of `set-mark'."
1180 1181 1182
  (if (or force mark-active)
      (marker-position (mark-marker))
    (error "The mark is not currently active")))
Jim Blandy's avatar
Jim Blandy committed
1183 1184 1185 1186 1187 1188 1189 1190 1191 1192

(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.

1193
Novice Emacs Lisp programmers often try to use the mark for the wrong
Jim Blandy's avatar
Jim Blandy committed
1194 1195 1196 1197 1198 1199 1200
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)))."

1201 1202
  (setq mark-active t)
  (run-hooks 'activate-mark-hook)
Jim Blandy's avatar
Jim Blandy committed
1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214
  (set-marker (mark-marker) pos (current-buffer)))

(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.")

(defun set-mark-command (arg)
  "Set mark at where point is, or jump to mark.
1215 1216
With no prefix argument, set mark, and push old mark position on mark ring.
With argument, jump to mark, and pop a new position for mark off the ring.
Jim Blandy's avatar
Jim Blandy committed
1217

1218
Novice Emacs Lisp programmers often try to use the mark for the wrong
Jim Blandy's avatar
Jim Blandy committed
1219 1220 1221 1222
purposes.  See the documentation of `set-mark' for more information."
  (interactive "P")
  (if (null arg)
      (push-mark)
1223
    (if (null (mark t))
Jim Blandy's avatar
Jim Blandy committed
1224 1225 1226 1227 1228 1229 1230 1231
	(error "No mark set in this buffer")
      (goto-char (mark))
      (pop-mark))))

(defun push-mark (&optional location nomsg)
  "Set mark at LOCATION (point, by default) and push old mark on mark ring.
Displays \"Mark set\" unless the optional second arg NOMSG is non-nil.

1232
Novice Emacs Lisp programmers often try to use the mark for the wrong
Jim Blandy's avatar
Jim Blandy committed
1233
purposes.  See the documentation of `set-mark' for more information."
1234
  (if (null (mark t))
Jim Blandy's avatar
Jim Blandy committed
1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256
      nil
    (setq mark-ring (cons (copy-marker (mark-marker)) mark-ring))
    (if (> (length mark-ring) mark-ring-max)
	(progn
	  (move-marker (car (nthcdr mark-ring-max mark-ring)) nil)
	  (setcdr (nthcdr (1- mark-ring-max) mark-ring) nil))))
  (set-mark (or location (point)))
  (or nomsg executing-macro (> (minibuffer-depth) 0)
      (message "Mark set"))
  nil)

(defun pop-mark ()
  "Pop off mark ring into the buffer's actual mark.
Does not set point.  Does nothing if mark ring is empty."
  (if mark-ring
      (progn
	(setq mark-ring (nconc mark-ring (list (copy-marker (mark-marker)))))
	(set-mark (+ 0 (car mark-ring)))
	(move-marker (car mark-ring) nil)
	(if (null (mark)) (ding))
	(setq mark-ring (cdr mark-ring)))))

1257
(defalias 'exchange-dot-and-mark 'exchange-point-and-mark)
Jim Blandy's avatar
Jim Blandy committed
1258
(defun exchange-point-and-mark ()
1259 1260 1261
  "Put the mark where point is now, and point where the mark is now.
This command works even when the mark is not active,
and it reactivates the mark."
Jim Blandy's avatar
Jim Blandy committed
1262
  (interactive nil)
1263
  (let ((omark (mark t)))
Jim Blandy's avatar
Jim Blandy committed
1264 1265 1266 1267 1268 1269
    (if (null omark)
	(error "No mark set in this buffer"))
    (set-mark (point))
    (goto-char omark)
    nil))

1270 1271 1272 1273 1274
(defvar next-line-add-newlines t
  "*If non-nil, next-line will insert a newline into the buffer
 when invoked with no newline character between the point and the end
 of the buffer.")

Jim Blandy's avatar
Jim Blandy committed
1275 1276 1277 1278 1279
(defun next-line (arg)
  "Move cursor vertically down ARG lines.
If there is no character in the target line exactly under the current column,
the cursor is positioned after the character in that line which spans this
column, or at the end of the line if it is not long enough.
1280 1281 1282 1283 1284
If there is no line in the buffer after this one, behavior depends on the
value of next-line-add-newlines.  If non-nil, a newline character is inserted
to create a line and the cursor moves to that line, otherwise the cursor is
moved to the end of the buffer (if already at the end of the buffer, an error
is signaled).
Jim Blandy's avatar
Jim Blandy committed
1285 1286 1287 1288 1289 1290 1291 1292 1293 1294

The command \\[set-goal-column] can be used to create
a semipermanent goal column to which this command always moves.
Then it does not try to move vertically.  This goal column is stored
in `goal-column', which is nil when there is none.

If you are thinking of using this in a Lisp program, consider
using `forward-line' instead.  It is usually easier to use
and more reliable (no dependence on goal column, etc.)."
  (interactive "p")
1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308
  (let ((opoint (point)))
    (if next-line-add-newlines
	(if (/= arg 1)
	    (line-move arg)
	  (forward-line 1)
	  (if (or (= opoint (point)) (not (eq (preceding-char) ?\n