4.4BSD/usr/src/contrib/emacs-18.57/info/emacs-6

Info file ../info/emacs, produced by Makeinfo, -*- Text -*- from
input file emacs.tex.

This file documents the GNU Emacs editor.

Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
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Permission is granted to copy and distribute translations of this
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translation approved by the author instead of in the original English.

File: emacs, Node: Windows, Next: Major Modes, Prev: Buffers, Up: Top

Multiple Windows
****************

Emacs can split the screen into two or many windows, which can
display parts of different buffers, or different parts of one buffer.

* Menu:

* Basic Window:: Introduction to Emacs windows.
* Split Window:: New windows are made by splitting existing windows.
* Other Window:: Moving to another window or doing something to it.
* Pop Up Window:: Finding a file or buffer in another window.
* Change Window:: Deleting windows and changing their sizes.

File: emacs, Node: Basic Window, Next: Split Window, Prev: Windows, Up: Windows

Concepts of Emacs Windows
=========================

When multiple windows are being displayed, each window has an Emacs
buffer designated for display in it. The same buffer may appear in
more than one window; if it does, any changes in its text are
displayed in all the windows where it appears. But the windows
showing the same buffer can show different parts of it, because each
window has its own value of point.

At any time, one of the windows is the "selected window"; the buffer
this window is displaying is the current buffer. The terminal's
cursor shows the location of point in this window. Each other window
has a location of point as well, but since the terminal has only one
cursor there is no way to show where those locations are.

Commands to move point affect the value of point for the selected
Emacs window only. They do not change the value of point in any
other Emacs window, even one showing the same buffer. The same is
true for commands such as `C-x b' to change the selected buffer in
the selected window; they do not affect other windows at all.
However, there are other commands such as `C-x 4 b' that select a
different window and switch buffers in it. Also, all commands that
display information in a window, including (for example) `C-h f'
(`describe-function') and `C-x C-b' (`list-buffers'), work by
switching buffers in a nonselected window without affecting the
selected window.

Each window has its own mode line, which displays the buffer name,
modification status and major and minor modes of the buffer that is
displayed in the window. *Note Mode Line::, for full details on the
mode line.

File: emacs, Node: Split Window, Next: Other Window, Prev: Basic Window, Up: Windows

Splitting Windows
=================

`C-x 2'
Split the selected window into two windows, one above the other
(`split-window-vertically').

`C-x 5'
Split the selected window into two windows positioned side by
side (`split-window-horizontally').

The command `C-x 2' (`split-window-vertically') breaks the selected
window into two windows, one above the other. Both windows start out
displaying the same buffer, with the same value of point. By default
the two windows each get half the height of the window that was
split; a numeric argument specifies how many lines to give to the top
window.

`C-x 5' (`split-window-horizontally') breaks the selected window into
two side-by-side windows. A numeric argument specifies how many
columns to give the one on the left. A line of vertical bars
separates the two windows. Windows that are not the full width of
the screen have mode lines, but they are truncated; also, they do not
always appear in inverse video, because, the Emacs display routines
have not been taught how to display a region of inverse video that is
only part of a line on the screen.

When a window is less than the full width, text lines too long to fit
are frequent. Continuing all those lines might be confusing. The
variable `truncate-partial-width-windows' can be set non-`nil' to
force truncation in all windows less than the full width of the
screen, independent of the buffer being displayed and its value for
`truncate-lines'. *Note Continuation Lines::.

Horizontal scrolling is often used in side-by-side windows. *Note
Display::.

File: emacs, Node: Other Window, Next: Pop Up Window, Prev: Split Window, Up: Windows

Using Other Windows
===================

`C-x o'
Select another window (`other-window'). That is `o', not zero.

`C-M-v'
Scroll the next window (`scroll-other-window').

`M-x compare-windows'
Find next place where the text in the selected window does not
match the text in the next window.

To select a different window, use `C-x o' (`other-window'). That is
an `o', for `other', not a zero. When there are more than two
windows, this command moves through all the windows in a cyclic
order, generally top to bottom and left to right. From the rightmost
and bottommost window, it goes back to the one at the upper left
corner. A numeric argument means to move several steps in the cyclic
order of windows. A negative argument moves around the cycle in the
opposite order. When the minibuffer is active, the minibuffer is the
last window in the cycle; you can switch from the minibuffer window
to one of the other windows, and later switch back and finish
supplying the minibuffer argument that is requested. *Note
Minibuffer Edit::.

The usual scrolling commands (*note Display::.) apply to the selected
window only, but there is one command to scroll the next window.
`C-M-v' (`scroll-other-window') scrolls the window that `C-x o' would
select. It takes arguments, positive and negative, like `C-v'.

The command `M-x compare-windows' compares the text in the current
window with that in the next window. Comparison starts at point in
each window. Point moves forward in each window, a character at a
time in each window, until the next characters in the two windows are
different. Then the command is finished.

File: emacs, Node: Pop Up Window, Next: Change Window, Prev: Other Window, Up: Windows

Displaying in Another Window
============================

`C-x 4' is a prefix key for commands that select another window
(splitting the window if there is only one) and select a buffer in
that window. Different `C-x 4' commands have different ways of
finding the buffer to select.

`C-x 4 b BUFNAME RET'
Select buffer BUFNAME in another window. This runs
`switch-to-buffer-other-window'.

`C-x 4 f FILENAME RET'
Visit file FILENAME and select its buffer in another window.
This runs `find-file-other-window'. *Note Visiting::.

`C-x 4 d DIRECTORY RET'
Select a Dired buffer for directory DIRECTORY in another window.
This runs `dired-other-window'. *Note Dired::.

`C-x 4 m'
Start composing a mail message in another window. This runs
`mail-other-window', and its same-window version is `C-x m'
(*note Sending Mail::.).

`C-x 4 .'
Find a tag in the current tag table in another window. This
runs `find-tag-other-window', the multiple-window variant of
`M-.' (*note Tags::.).

File: emacs, Node: Change Window, Prev: Pop Up Window, Up: Windows

Deleting and Rearranging Windows
================================

`C-x 0'
Get rid of the selected window (`kill-window'). That is a zero.

`C-x 1'
Get rid of all windows except the selected one
(`delete-other-windows').

`C-x ^'
Make the selected window taller, at the expense of the other(s)
(`enlarge-window').

`C-x }'
Make the selected window wider (`enlarge-window-horizontally').

To delete a window, type `C-x 0' (`delete-window'). (That is a
zero.) The space occupied by the deleted window is distributed among
the other active windows (but not the minibuffer window, even if that
is active at the time). Once a window is deleted, its attributes are
forgotten; there is no automatic way to make another window of the
same shape or showing the same buffer. But the buffer continues to
exist, and you can select it in any window with `C-x b'.

`C-x 1' (`delete-other-windows') is more powerful than `C-x 0'; it
deletes all the windows except the selected one (and the minibuffer);
the selected window expands to use the whole screen except for the
echo area.

To readjust the division of space among existing windows, use `C-x ^'
(`enlarge-window'). It makes the currently selected window get one
line bigger, or as many lines as is specified with a numeric argument.
With a negative argument, it makes the selected window smaller. `C-x
}' (`enlarge-window-horizontally') makes the selected window wider by
the specified number of columns. The extra screen space given to a
window comes from one of its neighbors, if that is possible;
otherwise, all the competing windows are shrunk in the same
proportion. If this makes any windows too small, those windows are
deleted and their space is divided up. The minimum size is specified
by the variables `window-min-height' and `window-min-width'.

File: emacs, Node: Major Modes, Next: Indentation, Prev: Windows, Up: Top

Major Modes
***********

Emacs has many different "major modes", each of which customizes
Emacs for editing text of a particular sort. The major modes are
mutually exclusive, and each buffer has one major mode at any time.
The mode line normally contains the name of the current major mode,
in parentheses. *Note Mode Line::.

The least specialized major mode is called "Fundamental mode". This
mode has no mode-specific redefinitions or variable settings, so that
each Emacs command behaves in its most general manner, and each
option is in its default state. For editing any specific type of
text, such as Lisp code or English text, you should switch to the
appropriate major mode, such as Lisp mode or Text mode.

Selecting a major mode changes the meanings of a few keys to become
more specifically adapted to the language being edited. The ones
which are changed frequently are TAB, DEL, and LFD. In addition, the
commands which handle comments use the mode to determine how comments
are to be delimited. Many major modes redefine the syntactical
properties of characters appearing in the buffer. *Note Syntax::.

The major modes fall into three major groups. Lisp mode (which has
several variants), C mode and Muddle mode are for specific
programming languages. Text mode, Nroff mode, TeX mode and Outline
mode are for editing English text. The remaining major modes are not
intended for use on users' files; they are used in buffers created
for specific purposes by Emacs, such as Dired mode for buffers made
by Dired (*note Dired::.), and Mail mode for buffers made by `C-x m'
(*note Sending Mail::.), and Shell mode for buffers used for
communicating with an inferior shell process (*note Interactive
Shell::.).

Most programming language major modes specify that only blank lines
separate paragraphs. This is so that the paragraph commands remain
useful. *Note Paragraphs::. They also cause Auto Fill mode to use
the definition of TAB to indent the new lines it creates. This is
because most lines in a program are usually indented. *Note
Indentation::.

* Menu:

* Choosing Modes:: How major modes are specified or chosen.

File: emacs, Node: Choosing Modes, Prev: Major Modes, Up: Major Modes

How Major Modes are Chosen
==========================

You can select a major mode explicitly for the current buffer, but
most of the time Emacs determines which mode to use based on the file
name or some text in the file.

Explicit selection of a new major mode is done with a `M-x' command.
From the name of a major mode, add `-mode' to get the name of a
command to select that mode. Thus, you can enter Lisp mode by
executing `M-x lisp-mode'.

When you visit a file, Emacs usually chooses the right major mode
based on the file's name. For example, files whose names end in `.c'
are edited in C mode. The correspondence between file names and
major mode is controlled by the variable `auto-mode-alist'. Its
value is a list in which each element has the form

(REGEXP . MODE-FUNCTION)

For example, one element normally found in the list has the form
`("\\.c$" . c-mode)', and it is responsible for selecting C mode for
files whose names end in `.c'. (Note that `\\' is needed in Lisp
syntax to include a `\' in the string, which is needed to suppress
the special meaning of `.' in regexps.) The only practical way to
change this variable is with Lisp code.

You can specify which major mode should be used for editing a certain
file by a special sort of text in the first nonblank line of the
file. The mode name should appear in this line both preceded and
followed by `-*-'. Other text may appear on the line as well. For
example,

;-*-Lisp-*-

tells Emacs to use Lisp mode. Note how the semicolon is used to make
Lisp treat this line as a comment. Such an explicit specification
overrides any defaulting based on the file name.

Another format of mode specification is

-*-Mode: MODENAME;-*-

which allows other things besides the major mode name to be specified.
However, Emacs does not look for anything except the mode name.

The major mode can also be specified in a local variables list.
*Note File Variables::.

When a file is visited that does not specify a major mode to use, or
when a new buffer is created with `C-x b', the major mode used is
that specified by the variable `default-major-mode'. Normally this
value is the symbol `fundamental-mode', which specifies Fundamental
mode. If `default-major-mode' is `nil', the major mode is taken from
the previously selected buffer.

File: emacs, Node: Indentation, Next: Text, Prev: Major Modes, Up: Top

Indentation
***********

`TAB'
Indent current line "appropriately" in a mode-dependent fashion.

`LFD'
Perform RET followed by TAB (`newline-and-indent').

`M-^'
Merge two lines (`delete-indentation'). This would cancel out
the effect of LFD.

`C-M-o'
Split line at point; text on the line after point becomes a new
line indented to the same column that it now starts in
(`split-line').

`M-m'
Move (forward or back) to the first nonblank character on the
current line (`back-to-indentation').

`C-M-\'
Indent several lines to same column (`indent-region').

`C-x TAB'
Shift block of lines rigidly right or left (`indent-rigidly').

`M-i'
Indent from point to the next prespecified tab stop column
(`tab-to-tab-stop').

`M-x indent-relative'
Indent from point to under an indentation point in the previous
line.

Most programming languages have some indentation convention. For
Lisp code, lines are indented according to their nesting in
parentheses. The same general idea is used for C code, though many
details are different.

Whatever the language, to indent a line, use the TAB command. Each
major mode defines this command to perform the sort of indentation
appropriate for the particular language. In Lisp mode, TAB aligns
the line according to its depth in parentheses. No matter where in
the line you are when you type TAB, it aligns the line as a whole.
In C mode, TAB implements a subtle and sophisticated indentation
style that knows about many aspects of C syntax.

In Text mode, TAB runs the command `tab-to-tab-stop', which indents
to the next tab stop column. You can set the tab stops with `M-x
edit-tab-stops'.

* Menu:

* Indentation Commands:: Various commands and techniques for indentation.
* Tab Stops:: You can set arbitrary "tab stops" and then
indent to the next tab stop when you want to.
* Just Spaces:: You can request indentation using just spaces.

File: emacs, Node: Indentation Commands, Next: Tab Stops, Prev: Indentation, Up: Indentation

Indentation Commands and Techniques
===================================

If you just want to insert a tab character in the buffer, you can
type `C-q TAB'.

To move over the indentation on a line, do `Meta-m'
(`back-to-indentation'). This command, given anywhere on a line,
positions point at the first nonblank character on the line.

To insert an indented line before the current line, do `C-a C-o TAB'.
To make an indented line after the current line, use `C-e LFD'.

`C-M-o' (`split-line') moves the text from point to the end of the
line vertically down, so that the current line becomes two lines.
`C-M-o' first moves point forward over any spaces and tabs. Then it
inserts after point a newline and enough indentation to reach the
same column point is on. Point remains before the inserted newline;
in this regard, `C-M-o' resembles `C-o'.

To join two lines cleanly, use the `Meta-^' (`delete-indentation')
command to delete the indentation at the front of the current line,
and the line boundary as well. They are replaced by a single space,
or by no space if at the beginning of a line or before a `)' or after
a `('. To delete just the indentation of a line, go to the beginning
of the line and use `Meta-\' (`delete-horizontal-space'), which
deletes all spaces and tabs around the cursor.

There are also commands for changing the indentation of several lines
at once. `Control-Meta-\' (`indent-region') gives each line which
begins in the region the "usual" indentation by invoking TAB at the
beginning of the line. A numeric argument specifies the column to
indent to, and each line is shifted left or right so that its first
nonblank character appears in that column. `C-x TAB'
(`indent-rigidly') moves all of the lines in the region right by its
argument (left, for negative arguments). The whole group of lines
moves rigidly sideways, which is how the command gets its name.

`M-x indent-relative' indents at point based on the previous line
(actually, the last nonempty line.) It inserts whitespace at point,
moving point, until it is underneath an indentation point in the
previous line. An indentation point is the end of a sequence of
whitespace or the end of the line. If point is farther right than
any indentation point in the previous line, the whitespace before
point is deleted and the first indentation point then applicable is
used. If no indentation point is applicable even then,
`tab-to-tab-stop' is run (see next section).

`indent-relative' is the definition of TAB in Indented Text mode.
*Note Text::.

File: emacs, Node: Tab Stops, Next: Just Spaces, Prev: Indentation Commands, Up: Indentation

Tab Stops
=========

For typing in tables, you can use Text mode's definition of TAB,
`tab-to-tab-stop'. This command inserts indentation before point,
enough to reach the next tab stop column. If you are not in Text
mode, this function can be found on `M-i' anyway.

The tab stops used by `M-i' can be set arbitrarily by the user. They
are stored in a variable called `tab-stop-list', as a list of
column-numbers in increasing order.

The convenient way to set the tab stops is using `M-x
edit-tab-stops', which creates and selects a buffer containing a
description of the tab stop settings. You can edit this buffer to
specify different tab stops, and then type `C-c C-c' to make those
new tab stops take effect. In the tab stop buffer, `C-c C-c' runs
the function `edit-tab-stops-note-changes' rather than its usual
definition `save-buffer'. `edit-tab-stops' records which buffer was
current when you invoked it, and stores the tab stops back in that
buffer; normally all buffers share the same tab stops and changing
them in one buffer affects all, but if you happen to make
`tab-stop-list' local in one buffer then `edit-tab-stops' in that
buffer will edit the local settings.

Here is what the text representing the tab stops looks like for
ordinary tab stops every eight columns.

: : : : : :
0 1 2 3 4
0123456789012345678901234567890123456789012345678
To install changes, type C-c C-c

The first line contains a colon at each tab stop. The remaining
lines are present just to help you see where the colons are and know
what to do.

Note that the tab stops that control `tab-to-tab-stop' have nothing
to do with displaying tab characters in the buffer. *Note Display
Vars::, for more information on that.

File: emacs, Node: Just Spaces, Prev: Tab Stops, Up: Indentation

Tabs vs. Spaces
===============

Emacs normally uses both tabs and spaces to indent lines. If you
prefer, all indentation can be made from spaces only. To request
this, set `indent-tabs-mode' to `nil'. This is a per-buffer
variable; altering the variable affects only the current buffer, but
there is a default value which you can change as well. *Note Locals::.

There are also commands to convert tabs to spaces or vice versa,
always preserving the columns of all nonblank text. `M-x tabify'
scans the region for sequences of spaces, and converts sequences of
at least three spaces to tabs if that can be done without changing
indentation. `M-x untabify' changes all tabs in the region to
appropriate numbers of spaces.

File: emacs, Node: Text, Next: Programs, Prev: Indentation, Up: Top

Commands for Human Languages
****************************

The term "text" has two widespread meanings in our area of the
computer field. One is data that is a sequence of characters. Any
file that you edit with Emacs is text, in this sense of the word.
The other meaning is more restrictive: a sequence of characters in a
human language for humans to read (possibly after processing by a
text formatter), as opposed to a program or commands for a program.

Human languages have syntactic/stylistic conventions that can be
supported or used to advantage by editor commands: conventions
involving words, sentences, paragraphs, and capital letters. This
chapter describes Emacs commands for all of these things. There are
also commands for "filling", or rearranging paragraphs into lines of
approximately equal length. The commands for moving over and killing
words, sentences and paragraphs, while intended primarily for editing
text, are also often useful for editing programs.

Emacs has several major modes for editing human language text. If
the file contains text pure and simple, use Text mode, which
customizes Emacs in small ways for the syntactic conventions of text.
For text which contains embedded commands for text formatters, Emacs
has other major modes, each for a particular text formatter. Thus,
for input to TeX, you would use TeX mode; for input to nroff, Nroff
mode.

* Menu:

* Text Mode:: The major modes for editing text files.
* Nroff Mode:: The major mode for editing input to the formatter nroff.
* TeX Mode:: The major modes for editing input to the formatter TeX.
* Outline Mode::The major mode for editing outlines.
* Words:: Moving over and killing words.
* Sentences:: Moving over and killing sentences.
* Paragraphs:: Moving over paragraphs.
* Pages:: Moving over pages.
* Filling:: Filling or justifying text
* Case:: Changing the case of text

File: emacs, Node: Text Mode, Next: Words, Prev: Text, Up: Text

Text Mode
=========

Editing files of text in a human language ought to be done using Text
mode rather than Lisp or Fundamental mode. Invoke `M-x text-mode' to
enter Text mode. In Text mode, TAB runs the function
`tab-to-tab-stop', which allows you to use arbitrary tab stops set
with `M-x edit-tab-stops' (*note Tab Stops::.). Features concerned
with comments in programs are turned off except when explicitly
invoked. The syntax table is changed so that periods are not
considered part of a word, while apostrophes, backspaces and
underlines are.

A similar variant mode is Indented Text mode, intended for editing
text in which most lines are indented. This mode defines TAB to run
`indent-relative' (*note Indentation::.), and makes Auto Fill indent
the lines it creates. The result is that normally a line made by
Auto Filling, or by LFD, is indented just like the previous line.
Use `M-x indented-text-mode' to select this mode.

Entering Text mode or Indented Text mode calls with no arguments the
value of the variable `text-mode-hook', if that value exists and is
not `nil'. This value is also called when modes related to Text mode
are entered; this includes Nroff mode, TeX mode, Outline mode and
Mail mode. Your hook can look at the value of `major-mode' to see
which of these modes is actually being entered.

* Menu:

Two modes similar to Text mode are of use for editing text that is to
be passed through a text formatter before achieving the form in which
humans are to read it.

* Nroff Mode:: The major mode for editing input to the formatter nroff.
* TeX Mode:: The major modes for editing input to the formatter TeX.

Another similar mode is used for editing outlines. It allows you
to view the text at various levels of detail. You can view either
the outline headings alone or both headings and text; you can also
hide some of the headings at lower levels from view to make the high
level structure more visible.

* Outline Mode::The major mode for editing outlines.

File: emacs, Node: Nroff Mode, Next: TeX Mode, Prev: Text Mode, Up: Text Mode

Nroff Mode
----------

Nroff mode is a mode like Text mode but modified to handle nroff
commands present in the text. Invoke `M-x nroff-mode' to enter this
mode. It differs from Text mode in only a few ways. All nroff
command lines are considered paragraph separators, so that filling
will never garble the nroff commands. Pages are separated by `.bp'
commands. Comments start with backslash-doublequote. Also, three
special commands are provided that are not in Text mode:

`M-n'
Move to the beginning of the next line that isn't an nroff
command (`forward-text-line'). An argument is a repeat count.

`M-p'
Like `M-n' but move up (`backward-text-line').

`M-?'
Prints in the echo area the number of text lines (lines that are
not nroff commands) in the region (`count-text-lines').

The other feature of Nroff mode is that you can turn on Electric
Nroff newline mode. This is a minor mode that you can turn on or off
with `M-x electric-nroff-mode' (*note Minor Modes::.). When the mode
is on, each time you use RET to end a line that contains an nroff
command that opens a kind of grouping, the matching nroff command to
close that grouping is automatically inserted on the following line.
For example, if you are at the beginning of a line and type `. ( b
RET', the matching command `.)b' will be inserted on a new line
following point.

Entering Nroff mode calls with no arguments the value of the variable
`text-mode-hook', if that value exists and is not `nil'; then it does
the same with the variable `nroff-mode-hook'.

File: emacs, Node: TeX Mode, Next: Outline Mode, Prev: Nroff Mode, Up: Text Mode

TeX Mode
--------

TeX is a powerful text formatter written by Donald Knuth; it is also
free, like GNU Emacs. LaTeX is a simplified input format for TeX,
implemented by TeX macros. It comes with TeX.

Emacs has a special TeX mode for editing TeX input files. It
provides facilities for checking the balance of delimiters and for
invoking TeX on all or part of the file.

TeX mode has two variants, Plain TeX mode and LaTeX mode (actually
two distinct major modes which differ only slightly). They are
designed for editing the two different input formats. The command
`M-x tex-mode' looks at the contents of the buffer to determine
whether the contents appear to be LaTeX input or not; it then selects
the appropriate mode. If it can't tell which is right (e.g., the
buffer is empty), the variable `TeX-default-mode' controls which mode
is used.

The commands `M-x plain-tex-mode' and `M-x latex-mode' explicitly
select the two variants of TeX mode. Use these commands when `M-x
tex-mode' does not guess right.

* Menu:

* Editing: TeX Editing. Special commands for editing in TeX mode.
* Printing: TeX Print. Commands for printing part of a file with TeX.

TeX for Unix systems can be obtained from the University of
Washington for a distribution fee.

To order a full distribution, send $140.00 for a 1/2 inch 9-track
tape, $165.00 for two 4-track 1/4 inch cartridge tapes (foreign sites
$150.00, for 1/2 inch, $175.00 for 1/4 inch, to cover the extra
postage) payable to the University of Washington to:

The Director
Northwest Computer Support Group, DW-10
University of Washington
Seattle, Washington 98195

Purchase orders are acceptable, but there is an extra charge of
$10.00, to pay for processing charges. (Total of $150 for domestic
sites, $175 for foreign sites).

The normal distribution is a tar tape, blocked 20, 1600 bpi, on an
industry standard 2400 foot half-inch reel. The physical format for
the 1/4 inch streamer cartridges uses QIC-11, 8000 bpi, 4-track
serpentine recording for the SUN. Also, SystemV tapes can be written
in cpio format, blocked 5120 bytes, ASCII headers.

File: emacs, Node: TeX Editing, Next: TeX Print, Prev: TeX Mode, Up: TeX Mode

TeX Editing Commands
....................

Here are the special commands provided in TeX mode for editing the
text of the file.

`"'
Insert, according to context, either ```' or `"' or `'''
(`TeX-insert-quote').

`LFD'
Insert a paragraph break (two newlines) and check the previous
paragraph for unbalanced braces or dollar signs
(`TeX-terminate-paragraph').

`M-x validate-TeX-buffer'
Check each paragraph in the buffer for unbalanced braces or
dollar signs.

`M-{'
Insert `{}' and position point between them (`TeX-insert-braces').

`M-}'
Move forward past the next unmatched close brace (`up-list').

`C-c C-f'
Close a block for LaTeX (`TeX-close-LaTeX-block').

In TeX, the character `"' is not normally used; one uses `"' to start
a quotation and `"' to end one. TeX mode defines the key `"' to
insert `"' after whitespace or an open brace, `"' after a backslash,
or `"' otherwise. This is done by the command `TeX-insert-quote'.
If you need the character `"' itself in unusual contexts, use `C-q'
to insert it. Also, `"' with a numeric argument always inserts that
number of `"' characters.

In TeX mode, `$' has a special syntax code which attempts to
understand the way TeX math mode delimiters match. When you insert a
`$' that is meant to exit math mode, the position of the matching `$'
that entered math mode is displayed for a second. This is the same
feature that displays the open brace that matches a close brace that
is inserted. However, there is no way to tell whether a `$' enters
math mode or leaves it; so when you insert a `$' that enters math
mode, the previous `$' position is shown as if it were a match, even
though they are actually unrelated.

If you prefer to keep braces balanced at all times, you can use `M-{'
(`TeX-insert-braces') to insert a pair of braces. It leaves point
between the two braces so you can insert the text that belongs inside.
Afterward, use the command `M-}' (`up-list') to move forward past the
close brace.

There are two commands for checking the matching of braces. LFD
(`TeX-terminate-paragraph') checks the paragraph before point, and
inserts two newlines to start a new paragraph. It prints a message
in the echo area if any mismatch is found. `M-x validate-TeX-buffer'
checks the entire buffer, paragraph by paragraph. When it finds a
paragraph that contains a mismatch, it displays point at the
beginning of the paragraph for a few seconds and pushes a mark at
that spot. Scanning continues until the whole buffer has been
checked or until you type another key. The positions of the last
several paragraphs with mismatches can be found in the mark ring
(*note Mark Ring::.).

Note that square brackets and parentheses are matched in TeX mode,
not just braces. This is wrong for the purpose of checking TeX syntax.
However, parentheses and square brackets are likely to be used in
text as matching delimiters and it is useful for the various motion
commands and automatic match display to work with them.

In LaTeX input, `\begin' and `\end' commands must balance. After you
insert a `\begin', use `C-c C-f' (`TeX-close-LaTeX-block') to insert
automatically a matching `\end' (on a new line following the
`\begin'). A blank line is inserted between the two, and point is
left there.

File: emacs, Node: TeX Print, Prev: TeX Editing, Up: TeX Mode

TeX Printing Commands
.....................

You can invoke TeX as an inferior of Emacs on either the entire
contents of the buffer or just a region at a time. Running TeX in
this way on just one chapter is a good way to see what your changes
look like without taking the time to format the entire file.

`C-c C-r'
Invoke TeX on the current region, plus the buffer's header
(`TeX-region').

`C-c C-b'
Invoke TeX on the entire current buffer (`TeX-buffer').

`C-c C-l'
Recenter the window showing output from the inferior TeX so that
the last line can be seen (`TeX-recenter-output-buffer').

`C-c C-k'
Kill the inferior TeX (`TeX-kill-job').

`C-c C-p'
Print the output from the last `C-c C-r' or `C-c C-b' command
(`TeX-print').

`C-c C-q'
Show the printer queue (`TeX-show-print-queue').

You can pass the current buffer through an inferior TeX by means of
`C-c C-b' (`TeX-buffer'). The formatted output appears in a file in
`/tmp'; to print it, type `C-c C-p' (`TeX-print'). Afterward use
`C-c C-q' (`TeX-show-print-queue') to view the progress of your
output towards being printed.

The console output from TeX, including any error messages, appear in
a buffer called `*TeX-shell*'. If TeX gets an error, you can switch
to this buffer and feed it input (this works as in Shell mode; *note
Interactive Shell::.). Without switching to this buffer you can
scroll it so that its last line is visible by typing `C-c C-l'.

Type `C-c C-k' (`TeX-kill-job') to kill the TeX process if you see
that its output is no longer useful. Using `C-c C-b' or `C-c C-r'
also kills any TeX process still running.

You can also pass an arbitrary region through an inferior TeX by
typing `C-c C-r' (`TeX-region'). This is tricky, however, because
most files of TeX input contain commands at the beginning to set
parameters and define macros, without which no later part of the file
will format correctly. To solve this problem, `C-c C-r' allows you
to designate a part of the file as containing essential commands; it
is included before the specified region as part of the input to TeX.
The designated part of the file is called the "header".

To indicate the bounds of the header in Plain TeX mode, you insert
two special strings in the file. Insert `%**start of header' before
the header, and `%**end of header' after it. Each string must appear
entirely on one line, but there may be other text on the line before
or after. The lines containing the two strings are included in the
header. If `%**start of header' does not appear within the first 100
lines of the buffer, `C-c C-r' assumes that there is no header.

In LaTeX mode, the header begins with `\documentstyle' and ends with
`\begin{document}'. These are commands that LaTeX requires you to
use in any case, so nothing special needs to be done to identify the
header.

Entering either kind of TeX mode calls with no arguments the value of
the variable `text-mode-hook', if that value exists and is not `nil';
then it does the same with the variable `TeX-mode-hook'. Finally it
does the same with either `plain-TeX-mode-hook' or `LaTeX-mode-hook'.

File: emacs, Node: Outline Mode, Prev: TeX Mode, Up: Text Mode

Outline Mode
------------

Outline mode is a major mode much like Text mode but intended for
editing outlines. It allows you to make parts of the text
temporarily invisible so that you can see just the overall structure
of the outline. Type `M-x outline-mode' to turn on Outline mode in
the current buffer.

Entering Outline mode calls with no arguments the value of the
variable `text-mode-hook', if that value exists and is not `nil';
then it does the same with the variable `outline-mode-hook'.

When a line is invisible in outline mode, it does not appear on the
screen. The screen appears exactly as if the invisible line were
deleted, except that an ellipsis (three periods in a row) appears at
the end of the previous visible line (only one ellipsis no matter how
many invisible lines follow).

All editing commands treat the text of the invisible line as part of
the previous visible line. For example, `C-n' moves onto the next
visible line. Killing an entire visible line, including its
terminating newline, really kills all the following invisible lines
along with it; yanking it all back yanks the invisible lines and they
remain invisible.

* Menu:

* Format: Outline Format. What the text of an outline looks like.
* Motion: Outline Motion. Special commands for moving through outlines.
* Visibility: Outline Visibility. Commands to control what is visible.

File: emacs, Node: Outline Format, Next: Outline Motion, Prev: Outline Mode, Up: Outline Mode

Format of Outlines
..................

Outline mode assumes that the lines in the buffer are of two types:
"heading lines" and "body lines". A heading line represents a topic
in the outline. Heading lines start with one or more stars; the
number of stars determines the depth of the heading in the outline
structure. Thus, a heading line with one star is a major topic; all
the heading lines with two stars between it and the next one-star
heading are its subtopics; and so on. Any line that is not a heading
line is a body line. Body lines belong to the preceding heading
line. Here is an example:

* Food

This is the body,
which says something about the topic of food.

** Delicious Food

This is the body of the second-level header.

** Distasteful Food

This could have
a body too, with
several lines.

*** Dormitory Food

* Shelter

A second first-level topic with its header line.

A heading line together with all following body lines is called
collectively an "entry". A heading line together with all following
deeper heading lines and their body lines is called a "subtree".

You can customize the criterion for distinguishing heading lines by
setting the variable `outline-regexp'. Any line whose beginning has
a match for this regexp is considered a heading line. Matches that
start within a line (not at the beginning) do not count. The length
of the matching text determines the level of the heading; longer
matches make a more deeply nested level. Thus, for example, if a
text formatter has commands `@chapter', `@section' and `@subsection'
to divide the document into chapters and sections, you could make
those lines count as heading lines by setting `outline-regexp' to
`"@chap\\|@\$sub\$*section"'. Note the trick: the two words
`chapter' and `section' are equally long, but by defining the regexp
to match only `chap' we ensure that the length of the text matched on
a chapter heading is shorter, so that Outline mode will know that
sections are contained in chapters. This works as long as no other
command starts with `@chap'.

Outline mode makes a line invisible by changing the newline before it
into an ASCII Control-M (code 015). Most editing commands that work
on lines treat an invisible line as part of the previous line
because, strictly speaking, it is part of that line, since there is
no longer a newline in between. When you save the file in Outline
mode, Control-M characters are saved as newlines, so the invisible
lines become ordinary lines in the file. But saving does not change
the visibility status of a line inside Emacs.

File: emacs, Node: Outline Motion, Next: Outline Visibility, Prev: Outline Format, Up: Outline Mode

Outline Motion Commands
.......................

There are some special motion commands in Outline mode that move
backward and forward to heading lines.

`C-c C-n'
Move point to the next visible heading line
(`outline-next-visible-heading').

`C-c C-p'
Move point to the previous visible heading line
(`outline-previous-visible-heading').

`C-c C-f'
Move point to the next visible heading line at the same level as
the one point is on (`outline-forward-same-level').

`C-c C-b'
Move point to the previous visible heading line at the same
level (`outline-backward-same-level').

`C-c C-u'
Move point up to a lower-level (more inclusive) visible heading
line (`outline-up-heading').

`C-c C-n' (`next-visible-heading') moves down to the next heading
line. `C-c C-p' (`previous-visible-heading') moves similarly
backward. Both accept numeric arguments as repeat counts. The names
emphasize that invisible headings are skipped, but this is not really
a special feature. All editing commands that look for lines ignore
the invisible lines automatically.

More advanced motion commands understand the levels of headings. The
commands `C-c C-f' (`outline-forward-same-level') and `C-c C-b'
(`outline-backward-same-level') move from one heading line to another
visible heading at the same depth in the outline. `C-c C-u'
(`outline-up-heading') moves backward to another heading that is less
deeply nested.

File: emacs, Node: Outline Visibility, Prev: Outline Motion, Up: Outline Mode

Outline Visibility Commands
...........................

The other special commands of outline mode are used to make lines
visible or invisible. Their names all start with `hide' or `show'.
Most of them fall into pairs of opposites. They are not undoable;
instead, you can undo right past them. Making lines visible or
invisible is simply not recorded by the undo mechanism.

`M-x hide-body'
Make all body lines in the buffer invisible.

`M-x show-all'
Make all lines in the buffer visible.

`C-c C-h'
Make everything under this heading invisible, not including this
heading itself
(`hide-subtree').

`C-c C-s'
Make everything under this heading visible, including body,
subheadings, and their bodies (`show-subtree').

`M-x hide-leaves'
Make the body of this heading line, and of all its subheadings,
invisible.

`M-x show-branches'
Make all subheadings of this heading line, at all levels, visible.

`C-c C-i'
Make immediate subheadings (one level down) of this heading line
visible (`show-children').

`M-x hide-entry'
Make this heading line's body invisible.

`M-x show-entry'
Make this heading line's body visible.

Two commands that are exact opposites are `M-x hide-entry' and `M-x
show-entry'. They are used with point on a heading line, and apply
only to the body lines of that heading. The subtopics and their
bodies are not affected.

Two more powerful opposites are `C-c C-h' (`hide-subtree') and `C-c
C-s' (`show-subtree'). Both expect to be used when point is on a
heading line, and both apply to all the lines of that heading's
"subtree": its body, all its subheadings, both direct and indirect,
and all of their bodies. In other words, the subtree contains
everything following this heading line, up to and not including the
next heading of the same or higher rank.

Intermediate between a visible subtree and an invisible one is having
all the subheadings visible but none of the body. There are two
commands for doing this, depending on whether you want to hide the
bodies or make the subheadings visible. They are `M-x hide-leaves'
and `M-x show-branches'.

A little weaker than `show-branches' is `C-c C-i' (`show-children').
It makes just the direct subheadings visible--those one level down.
Deeper subheadings remain invisible, if they were invisible.

Two commands have a blanket effect on the whole file. `M-x
hide-body' makes all body lines invisible, so that you see just the
outline structure. `M-x show-all' makes all lines visible. These
commands can be thought of as a pair of opposites even though `M-x
show-all' applies to more than just body lines.

The use of ellipses at the ends of visible lines can be turned off by
setting `selective-display-ellipses' to `nil'. Then there is no
visible indication of the presence of invisible lines.

File: emacs, Node: Words, Next: Sentences, Prev: Text Mode, Up: Text

Words
=====

Emacs has commands for moving over or operating on words. By
convention, the keys for them are all `Meta-' characters.

`M-f'
Move forward over a word (`forward-word').

`M-b'
Move backward over a word (`backward-word').

`M-d'
Kill up to the end of a word (`kill-word').

`M-DEL'
Kill back to the beginning of a word (`backward-kill-word').

`M-@'
Mark the end of the next word (`mark-word').

`M-t'
Transpose two words; drag a word forward or backward across
other words (`transpose-words').

Notice how these keys form a series that parallels the
character-based `C-f', `C-b', `C-d', `C-t' and DEL. `M-@' is related
to `C-@', which is an alias for `C-SPC'.

The commands `Meta-f' (`forward-word') and `Meta-b' (`backward-word')
move forward and backward over words. They are thus analogous to
`Control-f' and `Control-b', which move over single characters. Like
their `Control-' analogues, `Meta-f' and `Meta-b' move several words
if given an argument. `Meta-f' with a negative argument moves
backward, and `Meta-b' with a negative argument moves forward.
Forward motion stops right after the last letter of the word, while
backward motion stops right before the first letter.

`Meta-d' (`kill-word') kills the word after point. To be precise, it
kills everything from point to the place `Meta-f' would move to.
Thus, if point is in the middle of a word, `Meta-d' kills just the
part after point. If some punctuation comes between point and the
next word, it is killed along with the word. (If you wish to kill
only the next word but not the punctuation before it, simply do
`Meta-f' to get the end, and kill the word backwards with
`Meta-DEL'.) `Meta-d' takes arguments just like `Meta-f'.

`Meta-DEL' (`backward-kill-word') kills the word before point. It
kills everything from point back to where `Meta-b' would move to. If
point is after the space in `FOO, BAR', then `FOO, ' is killed. (If
you wish to kill just `FOO', do `Meta-b Meta-d' instead of `Meta-DEL'.)

`Meta-t' (`transpose-words') exchanges the word before or containing
point with the following word. The delimiter characters between the
words do not move. For example, `FOO, BAR' transposes into
`BAR, FOO' rather than `BAR FOO,'. *Note Transpose::, for more on
transposition and on arguments to transposition commands.

To operate on the next N words with an operation which applies
between point and mark, you can either set the mark at point and then
move over the words, or you can use the command `Meta-@'
(`mark-word') which does not move point, but sets the mark where
`Meta-f' would move to. It can be given arguments just like `Meta-f'.

The word commands' understanding of syntax is completely controlled
by the syntax table. Any character can, for example, be declared to
be a word delimiter. *Note Syntax::.

File: emacs, Node: Sentences, Next: Paragraphs, Prev: Words, Up: Text

Sentences
=========

The Emacs commands for manipulating sentences and paragraphs are
mostly on `Meta-' keys, so as to be like the word-handling commands.

`M-a'
Move back to the beginning of the sentence (`backward-sentence').

`M-e'
Move forward to the end of the sentence (`forward-sentence').

`M-k'
Kill forward to the end of the sentence (`kill-sentence').

`C-x DEL'
Kill back to the beginning of the sentence
(`backward-kill-sentence').

The commands `Meta-a' and `Meta-e' (`backward-sentence' and
`forward-sentence') move to the beginning and end of the current
sentence, respectively. They were chosen to resemble `Control-a' and
`Control-e', which move to the beginning and end of a line. Unlike
them, `Meta-a' and `Meta-e' if repeated or given numeric arguments
move over successive sentences. Emacs assumes that the typist's
convention is followed, and thus considers a sentence to end wherever
there is a `.', `?' or `!' followed by the end of a line or two
spaces, with any number of `)', `]', `'', or `"' characters allowed
in between. A sentence also begins or ends wherever a paragraph
begins or ends.

Neither `M-a' nor `M-e' moves past the newline or spaces beyond the
sentence edge at which it is stopping.

Just as `C-a' and `C-e' have a kill command, `C-k', to go with them,
so `M-a' and `M-e' have a corresponding kill command `M-k'
(`kill-sentence') which kills from point to the end of the sentence.
With minus one as an argument it kills back to the beginning of the
sentence. Larger arguments serve as a repeat count.

There is a special command, `C-x DEL' (`backward-kill-sentence') for
killing back to the beginning of a sentence, because this is useful
when you change your mind in the middle of composing text.

The variable `sentence-end' controls recognition of the end of a
sentence. It is a regexp that matches the last few characters of a
sentence, together with the whitespace following the sentence. Its
normal value is

"[.?!][]\"')]*\$$\\|\t\\| \$[ \t\n]*"

This example is explained in the section on regexps. *Note Regexps::.