1 @c This is part of the Emacs manual.
2 @c Copyright (C) 1985, 1986, 1987, 1993, 1994, 1995, 1997, 2000, 2001,
3 @c 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
4 @c See file emacs.texi for copying conditions.
5 @node Basic, Minibuffer, Exiting, Top
6 @chapter Basic Editing Commands
9 @findex help-with-tutorial
10 Here we explain the basics of how to enter text, make corrections,
11 and save the text in a file. If this material is new to you, we
12 suggest you first run the Emacs learn-by-doing tutorial, by typing
13 @kbd{Control-h t} inside Emacs. (@code{help-with-tutorial}).
17 * Inserting Text:: Inserting text by simply typing it.
18 * Moving Point:: Moving the cursor to the place where you want to
20 * Erasing:: Deleting and killing text.
21 * Basic Undo:: Undoing recent changes in the text.
22 * Files: Basic Files. Visiting, creating, and saving files.
23 * Help: Basic Help. Asking what a character does.
24 * Blank Lines:: Making and deleting blank lines.
25 * Continuation Lines:: How Emacs displays lines too wide for the screen.
26 * Position Info:: What page, line, row, or column is point on?
27 * Arguments:: Numeric arguments for repeating a command N times.
28 * Repeating:: Repeating the previous command quickly.
32 @section Inserting Text
35 @cindex graphic characters
36 You can insert an ordinary @dfn{graphic character} (e.g., @samp{a},
37 @samp{B}, @samp{3}, and @samp{=}) by typing the associated key. This
38 adds the character to the buffer at point. Insertion moves point
39 forward, so that point remains just after the inserted text.
44 To end a line and start a new one, type @key{RET}. This key may be
45 labeled @key{Return} or @key{Enter} on your keyboard, but we refer to
46 it as @key{RET} in this manual. Pressing it inserts a newline
47 character in the buffer. If point is at the end of the line, this
48 creates a new blank line after it; if point is in the middle of a
49 line, the line is split at that position.
51 As we explain later in this manual, you can change the way Emacs
52 handles text insertion by turning on @dfn{minor modes}. For instance,
53 if you turn on a minor mode called @dfn{Auto Fill} mode, Emacs can
54 split lines automatically when they become too long (@pxref{Filling}).
55 If you turn on a minor mode called @dfn{Overwrite} mode, inserted
56 characters replace (overwrite) existing text, instead of shoving it to
57 the right. @xref{Minor Modes}.
62 Only graphic characters can be inserted by typing the associated
63 key; other keys act as editing commands and do not insert themselves.
64 For instance, @kbd{DEL} runs the command @code{delete-backward-char}
65 by default (some modes bind it to a different command); it does not
66 insert a literal @samp{DEL} character (@acronym{ASCII} character code
69 To insert a non-graphic character, or a character that your keyboard
70 does not support, first @dfn{quote} it by typing @kbd{C-q}
71 (@code{quoted-insert}). There are two ways to use @kbd{C-q}:
75 @kbd{C-q} followed by any non-graphic character (even @kbd{C-g})
76 inserts that character. For instance, @kbd{C-q @key{DEL}} inserts a
77 literal @samp{DEL} character.
80 @kbd{C-q} followed by a sequence of octal digits inserts the character
81 with the specified octal character code. You can use any number of
82 octal digits; any non-digit terminates the sequence. If the
83 terminating character is @key{RET}, it serves only to terminate the
84 sequence. Any other non-digit terminates the sequence and then acts
85 as normal input---thus, @kbd{C-q 1 0 1 B} inserts @samp{AB}.
87 The use of octal sequences is disabled in ordinary non-binary
88 Overwrite mode, to give you a convenient way to insert a digit instead
89 of overwriting with it.
92 @vindex read-quoted-char-radix
94 To use decimal or hexadecimal instead of octal, set the variable
95 @code{read-quoted-char-radix} to 10 or 16. If the radix is greater
96 than 10, some letters starting with @kbd{a} serve as part of a
97 character code, just like digits.
99 A numeric argument tells @kbd{C-q} how many copies of the quoted
100 character to insert (@pxref{Arguments}).
104 Instead of @kbd{C-q}, you can use @kbd{C-x 8 @key{RET}}
105 (@code{ucs-insert}) to insert a character based on its Unicode name or
106 code-point. This commands prompts for a character to insert, using
107 the minibuffer; you can specify the character using either (i) the
108 character's name in the Unicode standard, or (ii) the character's
109 code-point in the Unicode standard.
112 @section Changing the Location of Point
117 @cindex cursor motion
118 @cindex moving the cursor
119 To do more than insert characters, you have to know how to move
120 point (@pxref{Point}). The keyboard commands @kbd{C-f}, @kbd{C-b},
121 @kbd{C-n}, and @kbd{C-p} move point to the right, left, up and down
122 respectively. These are equivalent to the commands @kbd{@key{right}},
123 @kbd{@key{left}}, @kbd{@key{down}}, and @kbd{@key{up}}, entered using
124 the @dfn{arrow keys} present on many keyboards. Many Emacs users find
125 that it is slower to use the arrow keys than the equivalent control
126 keys. You can also click the left mouse button to move point to the
127 position clicked. Emacs also provides a variety of additional
128 keyboard commands that move point in more sophisticated ways.
143 @findex move-beginning-of-line
144 @findex move-end-of-line
146 @findex backward-char
148 @findex previous-line
149 @findex beginning-of-buffer
150 @findex end-of-buffer
153 @findex move-to-window-line
157 Move to the beginning of the line (@code{move-beginning-of-line}).
160 Move to the end of the line (@code{move-end-of-line}).
163 Move forward one character (@code{forward-char}).
166 Move backward one character (@code{backward-char}).
170 Move forward one word (@code{forward-word}).
174 Move backward one word (@code{backward-word}).
177 Move down one screen line (@code{next-line}). This command attempts
178 to keep the horizontal position unchanged, so if you start in the
179 middle of one line, you move to the middle of the next.
182 Move up one screen line (@code{previous-line}). This command
183 preserves position within the line, like @kbd{C-n}.
185 Without moving the text on the screen, reposition point on the left
186 margin of the center-most text line of the window; on subsequent
187 consecutive invocations, move point to the left margin of the top-most
188 line, the bottom-most line, and so forth, in cyclic order
189 (@code{move-to-window-line-top-bottom}).
191 A numeric argument says which screen line to place point on, counting
192 downward from the top of the window (zero means the top line). A
193 negative argument counts lines up from the bottom (@minus{}1 means the
197 Move to the top of the buffer (@code{beginning-of-buffer}). With
198 numeric argument @var{n}, move to @var{n}/10 of the way from the top.
199 @xref{Arguments}, for more information on numeric arguments.@refill
201 Move to the end of the buffer (@code{end-of-buffer}).
203 @itemx @key{PageDown}
205 Scroll the display one screen forward, and move point if necessary to
206 put it on the screen (@code{scroll-up}). If your keyboard has a
207 @key{PageDown} key (sometimes labelled @key{next}), it does the same
208 thing as @key{C-v}. Scrolling commands are described further in
213 Scroll one screen backward, and move point if necessary to put it on
214 the screen (@code{scroll-down}). If your keyboard has a @key{PageUp}
215 key (sometimes labelled @key{prior}), it does the same thing as
218 Read a number @var{n} and move point to buffer position @var{n}.
219 Position 1 is the beginning of the buffer.
222 Read a number @var{n} and move point to the beginning of line number
223 @var{n} (@code{goto-line}). Line 1 is the beginning of the buffer. If
224 point is on or just after a number in the buffer, that is the default
225 for @var{n}. Just type @key{RET} in the minibuffer to use it. You can
226 also specify @var{n} by giving @kbd{M-g M-g} a numeric prefix argument.
227 @xref{Select Buffer}, for the behavior of @kbd{M-g M-g} when you give it
228 a plain prefix argument.
230 @findex set-goal-column
232 Use the current column of point as the @dfn{semipermanent goal column}
233 for @kbd{C-n} and @kbd{C-p} (@code{set-goal-column}). When a
234 semipermanent goal column is in effect, those commands always try to
235 move to this column, or as close as possible to it, after moving
236 vertically. The goal column remains in effect until canceled.
238 Cancel the goal column. Henceforth, @kbd{C-n} and @kbd{C-p} try to
239 preserve the horizontal position, as usual.
242 @vindex line-move-visual
243 When a line of text in the buffer is longer than the width of the
244 window, Emacs usually displays it on two or more @dfn{screen lines}.
245 For convenience, @kbd{C-n} and @kbd{C-p} move point by screen lines,
246 as do the equivalent keys @kbd{@key{down}} and @kbd{@key{up}}. You
247 can force these commands to move according to @dfn{logical lines}
248 (i.e., according to the text lines in the buffer) by setting the
249 variable @code{line-move-visual} to @code{nil}; if a logical line
250 occupies multiple screen lines, the cursor then skips over the
251 additional screen lines. Moving by logical lines was the default
252 behavior prior to Emacs 23.1. For details, see @ref{Continuation
253 Lines}. @xref{Variables}, for how to set variables such as
254 @code{line-move-visual}.
256 Unlike @kbd{C-n} and @kbd{C-p}, most of the Emacs commands that work
257 on lines work on @emph{logical} lines. For instance, @kbd{C-a}
258 (@code{move-beginning-of-line}) and @kbd{C-e}
259 (@code{move-end-of-line}) respectively move to the beginning and end
260 of the logical line. Whenever we encounter commands that work on
261 screen lines, such as @kbd{C-n} and @kbd{C-p}, we will point these
265 When @code{line-move-visual} is @code{nil}, you can also set the
266 variable @code{track-eol} to a non-@code{nil} value. Then @kbd{C-n}
267 and @kbd{C-p}, when starting at the end of the logical line, move to
268 the end of the next logical line. Normally, @code{track-eol} is
271 @vindex next-line-add-newlines
272 @kbd{C-n} normally stops at the end of the buffer when you use it on
273 the last line of the buffer. However, if you set the variable
274 @code{next-line-add-newlines} to a non-@code{nil} value, @kbd{C-n} on
275 the last line of a buffer creates an additional line at the end and
279 @section Erasing Text
283 @itemx @key{Backspace}
284 Delete the character before point (@code{delete-backward-char}).
287 Delete the character after point (@code{delete-char}).
289 Kill to the end of the line (@code{kill-line}).
291 Kill forward to the end of the next word (@code{kill-word}).
293 Kill back to the beginning of the previous word
294 (@code{backward-kill-word}).
297 The key @kbd{@key{DEL}} (@code{delete-backward-char}) removes the
298 character before point, moving the cursor and all the characters after
299 it backwards. On most keyboards, @key{DEL} is labelled
300 @key{Backspace}, but we refer to it as @key{DEL} in this manual. Do
301 not confuse @key{DEL} with another key, labelled @key{Delete}, that
302 exists on many keyboards; we will discuss @key{Delete} momentarily.
304 Typing @key{DEL} when the cursor is at the beginning of a line
305 deletes the preceding newline character, joining the line with the one
308 On some text-only terminals, Emacs may not recognize the @key{DEL}
309 key properly. If @key{DEL} does not do the right thing (e.g., if it
310 deletes characters forwards), see @ref{DEL Does Not Delete}.
312 @cindex killing characters and lines
313 @cindex deleting characters and lines
314 @cindex erasing characters and lines
315 The key @kbd{C-d} (@code{delete-char}) deletes the character after
316 point, i.e., the character under the cursor. This shifts the rest of
317 the text on the line to the left. If you type @kbd{C-d} at the end of
318 a line, it joins that line with the following line. This command is
319 also bound to the key labelled @key{Delete} on many keyboards.
321 To erase a larger amount of text, use the @kbd{C-k} key, which
322 erases (kills) a line at a time. If you type @kbd{C-k} at the
323 beginning or middle of a line, it kills all the text up to the end of
324 the line. If you type @kbd{C-k} at the end of a line, it joins that
325 line with the following line.
327 To learn more about killing text, see @ref{Killing}.
330 @section Undoing Changes
334 Undo one entry of the undo records---usually, one command worth
341 Emacs records a list of changes made in the buffer text, so you can
342 undo recent changes. This is done using the @code{undo} command,
343 which is bound to @kbd{C-/} (as well as @kbd{C-x u} and @kbd{C-_}).
344 Normally, this command undoes the last change, moving point back to
345 where it was before the change. The undo command applies only to
346 changes in the buffer; you can't use it to undo cursor motion.
348 Although each editing command usually makes a separate entry in the
349 undo records, very simple commands may be grouped together.
350 Sometimes, an entry may cover just part of a complex command.
352 If you repeat @kbd{C-/} (or its aliases), each repetition undoes
353 another, earlier change, back to the limit of the undo information
354 available. If all recorded changes have already been undone, the undo
355 command displays an error message and does nothing.
357 To learn more about the @code{undo} command, see @ref{Undo}.
362 Text that you insert in an Emacs buffer lasts only as long as the
363 Emacs session. To keep any text permanently, you must put it in a
364 @dfn{file}. Files are named units of text which are stored by the
365 operating system for you to retrieve later by name. To use the
366 contents of a file in any way, including editing it with Emacs, you
367 must specify the file name.
369 Suppose there is a file named @file{test.emacs} in your home
370 directory. To begin editing this file in Emacs, type
373 C-x C-f test.emacs @key{RET}
377 Here the file name is given as an @dfn{argument} to the command @kbd{C-x
378 C-f} (@code{find-file}). That command uses the @dfn{minibuffer} to
379 read the argument, and you type @key{RET} to terminate the argument
380 (@pxref{Minibuffer}).
382 Emacs obeys this command by @dfn{visiting} the file: it creates a
383 buffer, copies the contents of the file into the buffer, and then
384 displays the buffer for editing. If you alter the text, you can
385 @dfn{save} the new text in the file by typing @kbd{C-x C-s}
386 (@code{save-buffer}). This copies the altered buffer contents back
387 into the file @file{test.emacs}, making them permanent. Until you
388 save, the changed text exists only inside Emacs, and the file
389 @file{test.emacs} is unaltered.
391 To create a file, just visit it with @kbd{C-x C-f} as if it already
392 existed. This creates an empty buffer, in which you can insert the
393 text you want to put in the file. Emacs actually creates the file the
394 first time you save this buffer with @kbd{C-x C-s}.
396 To learn more about using files in Emacs, see @ref{Files}.
401 @cindex getting help with keys
402 If you forget what a key does, you can find out with the Help
403 character, which is @kbd{C-h} (or @key{F1}, which is an alias for
404 @kbd{C-h}). Type @kbd{C-h k}, followed by the key of interest; for
405 example, @kbd{C-h k C-n} tells you what @kbd{C-n} does. @kbd{C-h} is
406 a prefix key; @kbd{C-h k} is just one of its subcommands (the command
407 @code{describe-key}). The other subcommands of @kbd{C-h} provide
408 different kinds of help. Type @kbd{C-h} twice to get a description of
409 all the help facilities. @xref{Help}.
414 @cindex inserting blank lines
415 @cindex deleting blank lines
416 Here are special commands and techniques for inserting and deleting
421 Insert a blank line after the cursor (@code{open-line}).
423 Delete all but one of many consecutive blank lines
424 (@code{delete-blank-lines}).
431 @findex delete-blank-lines
432 We have seen how @kbd{@key{RET}} (@code{newline}) starts a new line
433 of text. However, it may be easier to see what you are doing if you
434 first make a blank line and then insert the desired text into it.
435 This is easy to do using the key @kbd{C-o} (@code{open-line}), which
436 inserts a newline after point but leaves point in front of the
437 newline. After @kbd{C-o}, type the text for the new line.
439 You can make several blank lines by typing @kbd{C-o} several times, or
440 by giving it a numeric argument specifying how many blank lines to make.
441 @xref{Arguments}, for how. If you have a fill prefix, the @kbd{C-o}
442 command inserts the fill prefix on the new line, if typed at the
443 beginning of a line. @xref{Fill Prefix}.
445 The easy way to get rid of extra blank lines is with the command
446 @kbd{C-x C-o} (@code{delete-blank-lines}). If point lies within a run
447 of several blank lines, @kbd{C-x C-o} deletes all but one of them. If
448 point is on a single blank line, @kbd{C-x C-o} deletes it. If point
449 is on a nonblank line, @kbd{C-x C-o} deletes all following blank
450 lines, if any exists.
452 @node Continuation Lines
453 @section Continuation Lines
455 @cindex continuation line
457 @cindex line wrapping
458 @cindex fringes, and continuation lines
459 Sometimes, a line of text in the buffer---a @dfn{logical line}---is
460 too long to fit in the window, and Emacs displays it as two or more
461 @dfn{screen lines}. This is called @dfn{line wrapping} or
462 @dfn{continuation}, and the long logical line is called a
463 @dfn{continued line}. On a graphical display, Emacs indicates line
464 wrapping with small bent arrows in the left and right window fringes.
465 On a text-only terminal, Emacs indicates line wrapping by displaying a
466 @samp{\} character at the right margin.
468 Most commands that act on lines act on logical lines, not screen
469 lines. For instance, @kbd{C-k} kills a logical line. As described
470 earlier, @kbd{C-n} (@code{next-line}) and @kbd{C-p}
471 (@code{previous-line}) are special exceptions: they move point down
472 and up, respectively, by one screen line (@pxref{Moving Point}).
475 @cindex line truncation, and fringes
476 Emacs can optionally @dfn{truncate} long logical lines instead of
477 continuing them. This means that every logical line occupies a single
478 screen line; if it is longer than the width of the window, the rest of
479 the line is not displayed. On a graphical display, a truncated line
480 is indicated by a small straight arrow in the right fringe; on a
481 text-only terminal, it is indicated by a @samp{$} character in the
482 right margin. @xref{Line Truncation}.
484 By default, continued lines are wrapped at the right window edge.
485 Since the wrapping may occur in the middle of a word, continued lines
486 can be difficult to read. The usual solution is to break your lines
487 before they get too long, by inserting newlines. If you prefer, you
488 can make Emacs insert a newline automatically when a line gets too
489 long, by using Auto Fill mode. @xref{Filling}.
492 Sometimes, you may need to edit files containing many long logical
493 lines, and it may not be practical to break them all up by adding
494 newlines. In that case, you can use Visual Line mode, which enables
495 @dfn{word wrapping}: instead of wrapping long lines exactly at the
496 right window edge, Emacs wraps them at the word boundaries (i.e.,
497 space or tab characters) nearest to the right window edge. Visual
498 Line mode also redefines editing commands such as @code{C-a},
499 @code{C-n}, and @code{C-k} to operate on screen lines rather than
500 logical lines. @xref{Visual Line Mode}.
503 @section Cursor Position Information
505 Here are commands to get information about the size and position of
506 parts of the buffer, and to count lines.
510 Display the page number of point, and the line number within that page.
512 Display the line number of point in the whole buffer.
513 @item M-x line-number-mode
514 @itemx M-x column-number-mode
515 Toggle automatic display of the current line number or column number.
516 @xref{Optional Mode Line}.
517 @item M-x count-lines-region
518 Display the number of lines in the current region. Normally bound to
519 @kbd{M-=}, except in a few specialist modes. @xref{Mark}, for
520 information about the region.
522 Display the character code of character after point, character position of
523 point, and column of point (@code{what-cursor-position}).
524 @item M-x hl-line-mode
525 Enable or disable highlighting of the current line. @xref{Cursor
527 @item M-x size-indication-mode
528 Toggle automatic display of the size of the buffer.
529 @xref{Optional Mode Line}.
534 @cindex line number commands
535 @cindex location of point
536 @cindex cursor location
537 @cindex point location
538 @kbd{M-x what-line} displays the current line number in the echo
539 area. This command is usually redundant, because the current line
540 number is shown in the mode line (@pxref{Mode Line}). However, if you
541 narrow the buffer, the mode line shows the line number relative to
542 the accessible portion (@pxref{Narrowing}). By contrast,
543 @code{what-line} displays both the line number relative to the
544 narrowed region and the line number relative to the whole buffer.
546 @kbd{M-x what-page} counts pages from the beginning of the file, and
547 counts lines within the page, showing both numbers in the echo area.
551 @findex count-lines-region
552 Use @kbd{M-x count-lines-region} (normally bound to @kbd{M-=}) to
553 display the number of lines in the region (@pxref{Mark}). @xref{Pages},
554 for the command @kbd{C-x l} which counts the lines in the current page.
557 @findex what-cursor-position
558 The command @kbd{C-x =} (@code{what-cursor-position}) shows
559 information about the current cursor position and the buffer contents
560 at that position. It displays a line in the echo area that looks like
564 Char: c (99, #o143, #x63) point=28062 of 36168 (78%) column=53
567 After @samp{Char:}, this shows the character in the buffer at point.
568 The text inside the parenthesis shows the corresponding decimal, octal
569 and hex character codes; for more information about how @kbd{C-x =}
570 displays character information, see @ref{International Chars}. After
571 @samp{point=} is the position of point as a character count (the first
572 character in the buffer is position 1, the second character is
573 position 2, and so on). The number after that is the total number of
574 characters in the buffer, and the number in parenthesis expresses the
575 position as a percentage of the total. After @samp{column=} is the
576 horizontal position of point, in columns counting from the left edge
579 If the buffer has been narrowed, making some of the text at the
580 beginning and the end temporarily inaccessible, @kbd{C-x =} displays
581 additional text describing the currently accessible range. For
582 example, it might display this:
585 Char: C (67, #o103, #x43) point=252 of 889 (28%) <231-599> column=0
589 where the two extra numbers give the smallest and largest character
590 position that point is allowed to assume. The characters between
591 those two positions are the accessible ones. @xref{Narrowing}.
594 @section Numeric Arguments
595 @cindex numeric arguments
596 @cindex prefix arguments
597 @cindex arguments to commands
599 In the terminology of mathematics and computing, @dfn{argument}
600 means ``data provided to a function or operation.'' You can give any
601 Emacs command a @dfn{numeric argument} (also called a @dfn{prefix
602 argument}). Some commands interpret the argument as a repetition
603 count. For example, giving @kbd{C-f} an argument of ten causes it to
604 move point forward by ten characters instead of one. With these
605 commands, no argument is equivalent to an argument of one, and
606 negative arguments cause them to move or act in the opposite
611 @findex digit-argument
612 @findex negative-argument
613 The easiest way to specify a numeric argument is to type a digit
614 and/or a minus sign while holding down the @key{META} key. For
622 moves down five lines. The keys @kbd{M-1}, @kbd{M-2}, and so on, as
623 well as @kbd{M--}, are bound to commands (@code{digit-argument} and
624 @code{negative-argument}) that set up an argument for the next
625 command. @kbd{Meta--} without digits normally means @minus{}1.
627 If you enter more than one digit, you need not hold down the
628 @key{META} key for the second and subsequent digits. Thus, to move
629 down fifty lines, type
636 Note that this @emph{does not} insert five copies of @samp{0} and move
637 down one line, as you might expect---the @samp{0} is treated as part
638 of the prefix argument.
640 (What if you do want to insert five copies of @samp{0}? Type @kbd{M-5
641 C-u 0}. Here, @kbd{C-u} ``terminates'' the prefix argument, so that
642 the next keystroke begins the command that you want to execute. Note
643 that this meaning of @kbd{C-u} applies only to this case. For the
644 usual role of @kbd{C-u}, see below.)
647 @findex universal-argument
648 Instead of typing @kbd{M-1}, @kbd{M-2}, and so on, another way to
649 specify a numeric argument is to type @kbd{C-u}
650 (@code{universal-argument}) followed by some digits, or (for a
651 negative argument) a minus sign followed by digits. A minus sign
652 without digits normally means @minus{}1.
654 @kbd{C-u} alone has the special meaning of ``four times'': it
655 multiplies the argument for the next command by four. @kbd{C-u C-u}
656 multiplies it by sixteen. Thus, @kbd{C-u C-u C-f} moves forward
657 sixteen characters. Other useful combinations are @kbd{C-u C-n},
658 @kbd{C-u C-u C-n} (move down a good fraction of a screen), @kbd{C-u
659 C-u C-o} (make ``a lot'' of blank lines), and @kbd{C-u C-k} (kill four
662 You can use a numeric argument before a self-inserting character to
663 insert multiple copies of it. This is straightforward when the
664 character is not a digit; for example, @kbd{C-u 6 4 a} inserts 64
665 copies of the character @samp{a}. But this does not work for
666 inserting digits; @kbd{C-u 6 4 1} specifies an argument of 641. You
667 can separate the argument from the digit to insert with another
668 @kbd{C-u}; for example, @kbd{C-u 6 4 C-u 1} does insert 64 copies of
669 the character @samp{1}.
671 Some commands care whether there is an argument, but ignore its
672 value. For example, the command @kbd{M-q} (@code{fill-paragraph})
673 fills text; with an argument, it justifies the text as well.
674 (@xref{Filling}, for more information on @kbd{M-q}.) For these
675 commands, it is enough to the argument with a single @kbd{C-u}.
677 Some commands use the value of the argument as a repeat count, but
678 do something special when there is no argument. For example, the
679 command @kbd{C-k} (@code{kill-line}) with argument @var{n} kills
680 @var{n} lines, including their terminating newlines. But @kbd{C-k}
681 with no argument is special: it kills the text up to the next newline,
682 or, if point is right at the end of the line, it kills the newline
683 itself. Thus, two @kbd{C-k} commands with no arguments can kill a
684 nonblank line, just like @kbd{C-k} with an argument of one.
685 (@xref{Killing}, for more information on @kbd{C-k}.)
687 A few commands treat a plain @kbd{C-u} differently from an ordinary
688 argument. A few others may treat an argument of just a minus sign
689 differently from an argument of @minus{}1. These unusual cases are
690 described when they come up; they exist to make an individual command
691 more convenient, and they are documented in that command's
692 documentation string.
694 We use the term ``prefix argument'' as well as ``numeric argument,''
695 to emphasize that you type these argument before the command, and to
696 distinguish them from minibuffer arguments that come after the
700 @section Repeating a Command
701 @cindex repeating a command
703 Many simple commands, such as those invoked with a single key or
704 with @kbd{M-x @var{command-name} @key{RET}}, can be repeated by
705 invoking them with a numeric argument that serves as a repeat count
706 (@pxref{Arguments}). However, if the command you want to repeat
707 prompts for input, or uses a numeric argument in another way, that
712 The command @kbd{C-x z} (@code{repeat}) provides another way to repeat
713 an Emacs command many times. This command repeats the previous Emacs
714 command, whatever that was. Repeating a command uses the same arguments
715 that were used before; it does not read new arguments each time.
717 To repeat the command more than once, type additional @kbd{z}'s: each
718 @kbd{z} repeats the command one more time. Repetition ends when you
719 type a character other than @kbd{z}, or press a mouse button.
721 For example, suppose you type @kbd{C-u 2 0 C-d} to delete 20
722 characters. You can repeat that command (including its argument) three
723 additional times, to delete a total of 80 characters, by typing @kbd{C-x
724 z z z}. The first @kbd{C-x z} repeats the command once, and each
725 subsequent @kbd{z} repeats it once again.
728 arch-tag: cda8952a-c439-41c1-aecf-4bc0d6482956