@c This is part of the Emacs manual.
-@c Copyright (C) 1985,86,87,93,94,95,97,99,00,2001 Free Software Foundation, Inc.
+@c Copyright (C) 1985, 1986, 1987, 1993, 1994, 1995, 1997, 1999, 2000,
+@c 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
@c See file emacs.texi for copying conditions.
@node Programs, Building, Text, Top
@chapter Editing Programs
Apply the usual indentation conventions of the language
(@pxref{Program Indent}).
@item
-Insert, kill or align comments (@pxref{Comments}).
-@item
Balance parentheses (@pxref{Parentheses}).
@item
+Insert, kill or align comments (@pxref{Comments}).
+@item
Highlight program syntax (@pxref{Font Lock}).
@end itemize
* Defuns:: Commands to operate on major top-level parts
of a program.
* Program Indent:: Adjusting indentation to show the nesting.
-* Comments:: Inserting, killing, and aligning comments.
* Parentheses:: Commands that operate on parentheses.
+* Comments:: Inserting, killing, and aligning comments.
* Documentation:: Getting documentation of functions you plan to call.
* Hideshow:: Displaying blocks selectively.
* Symbol Completion:: Completion on symbol names of your program or language.
* Misc for Programs:: Other Emacs features useful for editing programs.
* C Modes:: Special commands of C, C++, Objective-C,
Java, and Pike modes.
-* Fortran:: Fortran mode and its special features.
* Asm Mode:: Asm mode and its special features.
+@ifnottex
+* Fortran:: Fortran mode and its special features.
+@end ifnottex
@end menu
@node Program Modes
@cindex Perl mode
@cindex Icon mode
-@cindex Awk mode
@cindex Makefile mode
@cindex Tcl mode
@cindex CPerl mode
@cindex Metafont mode
@cindex Modula2 mode
@cindex Prolog mode
+@cindex Python mode
@cindex Simula mode
@cindex VHDL mode
@cindex M4 mode
@cindex Shell-script mode
@cindex Delphi mode
@cindex PostScript mode
+@cindex Conf mode
+@cindex DNS mode
The existing programming language major modes include Lisp, Scheme (a
variant of Lisp) and the Scheme-based DSSSL expression language, Ada,
-Awk, C, C++, Delphi (Object Pascal), Fortran (free format and fixed
+ASM, AWK, C, C++, Delphi (Object Pascal), Fortran (free format and fixed
format), Icon, IDL (CORBA), IDLWAVE, Java, Metafont (@TeX{}'s
companion for font creation), Modula2, Objective-C, Octave, Pascal,
-Perl, Pike, PostScript, Prolog, Simula, Tcl, and VHDL. There is
-also a major mode for makefiles, called Makefile mode. An alternative
-mode for Perl is called CPerl mode. Modes are available for the
-scripting languages of the common GNU and Unix shells, VMS DCL, and
+Perl, Pike, PostScript, Prolog, Python, Simula, Tcl, and VHDL. An
+alternative mode for Perl is called CPerl mode. Modes are available for
+the scripting languages of the common GNU and Unix shells, VMS DCL, and
MS-DOS/MS-Windows @samp{BAT} files. There are also major modes for
-editing various sorts of configuration files.
+editing makefiles, DNS master files, and various sorts of configuration
+files.
@kindex DEL @r{(programming modes)}
@findex c-electric-backspace
tab character before point, in these modes.
Separate manuals are available for the modes for Ada (@pxref{Top, , Ada
-Mode, ada-mode, Ada Mode}), C/C++/Objective C/Java/Corba IDL
+Mode, ada-mode, Ada Mode}), C/C++/Objective C/Java/Corba IDL/Pike/AWK
(@pxref{Top, , CC Mode, ccmode, CC Mode}) and the IDLWAVE modes
-(@pxref{Top, , IDLWAVE, idlwave, IDLWAVE User Manual}).
+(@pxref{Top, , IDLWAVE, idlwave, IDLWAVE User Manual}). For Fortran
+mode, see
+@iftex
+@ref{Fortran,,, emacs-xtra}.
+@end iftex
+@ifnottex
+@ref{Fortran}.
+@end ifnottex
+
@cindex mode hook
@vindex c-mode-hook
@node Defuns
@section Top-Level Definitions, or Defuns
- In Emacs, a major definition at the top level in the buffer is
-called a @dfn{defun}. The name comes from Lisp, but in Emacs we use
-it for all languages.
-
- In most programming language modes, Emacs assumes that a defun is
-any pair of parentheses (or braces, if the language uses braces this
-way) that starts at the left margin. For example, in C, the body of a
-function definition is normally a defun, because the open-brace that
-begins it is normally at the left margin. A variable's initializer
-can also count as a defun, if the open-brace that begins the
-initializer is at the left margin.
-
- However, some language modes provide their own code for recognizing
-defuns in a way that suits the language syntax and conventions better.
+ In Emacs, a major definition at the top level in the buffer,
+something like a function, is called a @dfn{defun}. The name comes
+from Lisp, but in Emacs we use it for all languages.
@menu
* Left Margin Paren:: An open-paren or similar opening delimiter
@cindex open-parenthesis in leftmost column
@cindex ( in leftmost column
- In most major modes, Emacs assumes that any opening delimiter found
-at the left margin is the start of a top-level definition, or defun.
-Therefore, @strong{never put an opening delimiter at the left margin
-unless it should have that significance.} For instance, never put an
+ Emacs assumes by default that any opening delimiter found at the
+left margin is the start of a top-level definition, or defun. You can
+override this default by setting this user option:
+
+@defvar open-paren-in-column-0-is-defun-start
+If this user option is set to @code{t} (the default), opening
+parentheses or braces at column zero always start defuns. When it's
+@code{nil}, defuns are found by searching for parens or braces at the
+outermost level. Some major modes, including C and related modes, set
+@code{open-paren-in-column-0-is-defun-start} buffer-locally to
+@code{nil}
+@end defvar
+
+ In modes where @code{open-paren-in-column-0-is-defun-start} is
+@code{t}, @strong{don't put an opening delimiter at the left margin
+unless it is a defun start}. For instance, never put an
open-parenthesis at the left margin in a Lisp file unless it is the
-start of a top-level list. Never put an open-brace or other opening
-delimiter at the beginning of a line of C code unless it is at top
-level.
+start of a top-level list.
If you don't follow this convention, not only will you have trouble
when you explicitly use the commands for motion by defuns; other
The most likely problem case is when you want an opening delimiter
at the start of a line inside a string. To avoid trouble, put an
-escape character (@samp{\}, in C and Emacs Lisp, @samp{/} in some
-other Lisp dialects) before the opening delimiter. This will not
-affect the contents of the string, but will prevent that opening
-delimiter from starting a defun. Here's an example:
+escape character (@samp{\}, in Emacs Lisp, @samp{/} in some other Lisp
+dialects) before the opening delimiter. This will not affect the
+contents of the string, but will prevent that opening delimiter from
+starting a defun. Here's an example:
@example
(insert "Foo:
")
@end example
+ To help you catch violations of this convention, Font Lock mode
+highlights confusing opening delimiters (those that ought to be
+quoted) in bold red.
+
In the earliest days, the original Emacs found defuns by moving
upward a level of parentheses or braces until there were no more
levels to go up. This always required scanning all the way back to
the operation, we changed Emacs to assume that any opening delimiter
at the left margin is the start of a defun. This heuristic is nearly
always right, and avoids the need to scan back to the beginning of the
-buffer. However, it mandates following the convention described
-above.
+buffer. However, now that modern computers are so powerful, this
+scanning is rarely slow enough to annoy, so we've provided a way to
+disable the heuristic.
@node Moving by Defuns
@subsection Moving by Defuns
defun. This is the easiest way to get ready to kill the defun in
order to move it to a different place in the file. If you use the
command while point is between defuns, it uses the following defun.
+Successive uses of @kbd{C-M-h}, or using it in Transient Mark mode
+when the mark is active, extends the end of the region to include one
+more defun each time.
In C mode, @kbd{C-M-h} runs the function @code{c-mark-function},
which is almost the same as @code{mark-defun}; the difference is that
@cindex buffer definitions index
@cindex tags
- The Imenu facility offers a way to find the the major definitions in
+ The Imenu facility offers a way to find the major definitions in
a file by name. It is also useful in text formatter major modes,
where it treats each chapter, section, etc., as a definition.
(@xref{Tags}, for a more powerful feature that handles multiple files
@code{imenu-add-menubar-index}. If you want to have this menu bar
item available for all buffers in a certain major mode, you can do
this by adding @code{imenu-add-menubar-index} to its mode hook. But
-if you have done that, you will have to wait each time you visit a
-file in that mode, while Emacs finds all the definitions in that
-buffer.
+if you have done that, you will have to wait a little while each time
+you visit a file in that mode, while Emacs finds all the definitions
+in that buffer.
@vindex imenu-auto-rescan
When you change the contents of a buffer, if you add or delete
definitions, you can update the buffer's index based on the
new contents by invoking the @samp{*Rescan*} item in the menu.
-Rescanning happens automatically you set @code{imenu-auto-rescan} to a
-non-@code{nil} value. There is no need to rescan because of small
+Rescanning happens automatically if you set @code{imenu-auto-rescan} to
+a non-@code{nil} value. There is no need to rescan because of small
changes in the text.
@vindex imenu-sort-function
@node Which Function
@subsection Which Function Mode
+@cindex current function name in mode line
Which Function mode is a minor mode that displays the current
function name in the mode line, updating it as you move around in a
@vindex which-func-modes
To enable (or disable) Which Function mode, use the command @kbd{M-x
which-function-mode}. This command is global; it applies to all
-buffers, both existing ones and those yet to be created. However,
-it only takes effect in certain major modes, those listed in the value of
-@code{which-func-modes}. If the value is @code{t}, then Which
-Function mode applies to all major modes that know how to support
-it---in other words, all the major modes that support Imenu.
+buffers, both existing ones and those yet to be created. However, it
+takes effect only in certain major modes, those listed in the value of
+@code{which-func-modes}. If the value is @code{t}, then Which Function
+mode applies to all major modes that know how to support it---in other
+words, all the major modes that support Imenu.
@node Program Indent
@section Indentation for Programs
@item @key{TAB}
Adjust indentation of current line.
@item C-j
-Equivalent to @key{RET} followed by @key{TAB} (@code{newline-and-indent}).
-@item @key{LINEFEED}
-This key, if the keyboard has it, is another way to enter @kbd{C-j}.
+Insert a newline, then adjust indentation of following line
+(@code{newline-and-indent}).
@end table
@kindex TAB @r{(programming modes)}
The basic indentation command is @key{TAB}, which gives the current line
the correct indentation as determined from the previous lines. The
function that @key{TAB} runs depends on the major mode; it is
-@code{indent-for-tab-command}
+@code{lisp-indent-line}
in Lisp mode, @code{c-indent-command} in C mode, etc. These functions
understand the syntax and conventions of different languages, but they all do
conceptually the same job: @key{TAB} in any programming-language major mode
that whitespace; otherwise, @key{TAB} keeps point fixed with respect to
the characters around it.
- Use @kbd{C-q @key{TAB}} to insert a tab at point.
+ Use @kbd{C-q @key{TAB}} to insert a tab character at point.
@kindex C-j
@findex newline-and-indent
When entering lines of new code, use @kbd{C-j}
-(@code{newline-and-indent}), which is equivalent to a @key{RET}
-followed by a @key{TAB}. @kbd{C-j} at the end of a line creates a
-blank line and then gives it the appropriate indentation.
-
- @key{TAB} indents lines that start within a parenthetical grouping
-each under the preceding line (or the text after the parenthesis).
-Therefore, if you manually give one of these lines a nonstandard
-indentation, the lines below will tend to follow it. This behavior is
-convenient in cases where you have overridden the standard result of
-@key{TAB} because you find it unaesthetic for a particular line.
-
- Remember that an open-parenthesis, open-brace or other opening delimiter
-at the left margin is assumed by Emacs (including the indentation routines)
-to be the start of a function. Therefore, you must never have an opening
-delimiter in column zero that is not the beginning of a function, not even
-inside a string. This restriction is vital for making the indentation
-commands fast; you must simply accept it. @xref{Left Margin Paren},
-for more information on this.
+(@code{newline-and-indent}), which inserts a newline and then adjusts
+indentation after it. (It also deletes any trailing whitespace which
+remains before the new newline.) Thus, @kbd{C-j} at the end of a line
+creates a blank line with appropriate indentation. In programming
+language modes, it is equivalent to @key{RET} @key{TAB}.
+
+ @key{TAB} indents a line that starts within a parenthetical grouping
+under the preceding line within the grouping, or the text after the
+parenthesis. Therefore, if you manually give one of these lines a
+nonstandard indentation, the lines below will tend to follow it. This
+behavior is convenient in cases where you have overridden the standard
+result of @key{TAB} because you find it unaesthetic for a particular
+line.
+
+ In some modes, an open-parenthesis, open-brace or other opening
+delimiter at the left margin is assumed by Emacs (including the
+indentation routines) to be the start of a function. This speeds up
+indentation commands. If you will be editing text which contains
+opening delimiters in column zero that aren't the beginning of a
+functions, even inside strings or comments, you must set
+@code{open-paren-in-column-0-is-defun-start}. @xref{Left Margin
+Paren}, for more information on this.
Normally, lines are indented with tabs and spaces. If you want Emacs
-to use spaces only, see @ref{Just Spaces}.
+to use spaces only, set @code{indent-tabs-mode} (@pxref{Just Spaces}).
@node Multi-line Indent
@subsection Indenting Several Lines
@table @kbd
@item C-M-q
-Reindent all the lines within one parenthetical grouping(@code{indent-sexp}).
+Reindent all the lines within one parenthetical grouping (@code{indent-pp-sexp}).
@item C-M-\
Reindent all lines in the region (@code{indent-region}).
@item C-u @key{TAB}
@end table
@kindex C-M-q
-@findex indent-sexp
+@findex indent-pp-sexp
You can reindent the contents of a single parenthetical grouping by
positioning point before the beginning of it and typing @kbd{C-M-q}
-(@code{indent-sexp} in Lisp mode, @code{c-indent-exp} in C mode; also
+(@code{indent-pp-sexp} in Lisp mode, @code{c-indent-exp} in C mode; also
bound to other suitable commands in other modes). The indentation of
-the line where the grouping starts is not changed; therefore, this
+the line where the grouping starts is not changed; therefore this
changes only the relative indentation within the grouping, not its
overall indentation. To correct that as well, type @key{TAB} first.
reindents the current line as usual, then reindents by the same amount
all the lines in the parenthetical grouping starting on the current
line. It is clever, though, and does not alter lines that start
-inside strings, or C preprocessor lines when in C mode.
+inside strings. Neither does it alter C preprocessor lines when in C
+mode, but it does reindent any continuation lines that may be attached
+to them.
@findex indent-code-rigidly
You can also perform this operation on the region, using the command
@kbd{M-x indent-code-rigidly}. It rigidly shifts all the lines in the
region sideways, like @code{indent-rigidly} does (@pxref{Indentation
Commands}). It doesn't alter the indentation of lines that start
-inside a comment or a string, unless the region starts inside that
-comment or string.
+inside a string, unless the region also starts inside that string.
+The prefix arg specifies the number of columns to indent.
@node Lisp Indent
@subsection Customizing Lisp Indentation
@vindex lisp-body-indent
Certain functions override the standard pattern. Functions whose
-names start with @code{def} treat the the second lines as the start of
+names start with @code{def} treat the second lines as the start of
a @dfn{body}, by indenting the second line @code{lisp-body-indent}
additional columns beyond the open-parenthesis that starts the
expression.
+@cindex @code{lisp-indent-function} property
You can override the standard pattern in various ways for individual
-functions, according to the @code{lisp-indent-function} property of the
-function name. There are four possibilities for this property:
-
-@table @asis
-@item @code{nil}
-This is the same as no property---use the standard indentation pattern.
-@item @code{defun}
-Handle this function like a @samp{def} construct: treat the second
-line as the start of a @dfn{body}.
-@item a number, @var{number}
-The first @var{number} arguments of the function are
-@dfn{distinguished} arguments; the rest are considered the body
-of the expression. A line in the expression is indented according to
-whether the first argument on it is distinguished or not. If the
-argument is part of the body, the line is indented @code{lisp-body-indent}
-more columns than the open-parenthesis starting the containing
-expression. If the argument is distinguished and is either the first
-or second argument, it is indented @emph{twice} that many extra columns.
-If the argument is distinguished and not the first or second argument,
-the line uses the standard pattern.
-@item a symbol, @var{symbol}
-@var{symbol} should be a function name; that function is called to
-calculate the indentation of a line within this expression. The
-function receives two arguments:
-@table @asis
-@item @var{state}
-The value returned by @code{parse-partial-sexp} (a Lisp primitive for
-indentation and nesting computation) when it parses up to the
-beginning of this line.
-@item @var{pos}
-The position at which the line being indented begins.
-@end table
-@noindent
-It should return either a number, which is the number of columns of
-indentation for that line, or a list whose car is such a number. The
-difference between returning a number and returning a list is that a
-number says that all following lines at the same nesting level should
-be indented just like this one; a list says that following lines might
-call for different indentations. This makes a difference when the
-indentation is being computed by @kbd{C-M-q}; if the value is a
-number, @kbd{C-M-q} need not recalculate indentation for the following
-lines until the end of the list.
-@end table
+functions, according to the @code{lisp-indent-function} property of
+the function name. Normally you would use this for macro definitions
+and specify it using the @code{declare} construct (@pxref{Defining
+Macros,,, elisp, the Emacs Lisp Reference Manual}).
@node C Indent
@subsection Commands for C Indentation
@kindex C-M-q @r{(C mode)}
@findex c-indent-exp
Reindent each line in the balanced expression that follows point
-(@code{c-indent-exp}). A prefix argument inhibits error checking and
-warning messages about invalid syntax.
+(@code{c-indent-exp}). A prefix argument inhibits warning messages
+about invalid syntax.
@item @key{TAB}
@findex c-indent-command
Reindent the current line, and/or in some cases insert a tab character
(@code{c-indent-command}).
+@vindex c-tab-always-indent
If @code{c-tab-always-indent} is @code{t}, this command always reindents
the current line and does nothing else. This is the default.
if @code{indent-tabs-mode} is @code{nil}).
Any other value (not @code{nil} or @code{t}) means always reindent the
-line, and also insert a tab if within a comment, a string, or a
-preprocessor directive.
+line, and also insert a tab if within a comment or a string.
@end table
To reindent the whole current buffer, type @kbd{C-x h C-M-\}. This
@subsection Customizing C Indentation
@cindex style (for indentation)
- C mode and related modes use a simple yet flexible mechanism for
-customizing indentation. The mechanism works in two steps: first it
-classifies the line syntactically according to its contents and context;
-second, it associates each kind of syntactic construct with an
-indentation offset based on your selected @dfn{style}.
+ C mode and related modes use a flexible mechanism for customizing
+indentation. C mode indents a source line in two steps: first it
+classifies the line syntactically according to its contents and
+context; second, it determines the indentation offset associated by
+your selected @dfn{style} with the syntactic construct and adds this
+onto the indentation of the @dfn{anchor statement}.
@table @kbd
-@item M-x c-set-style @key{RET} @var{style} @key{RET}
-Select predefined indentation style @var{style}.
+@item C-c . @key{RET} @var{style} @key{RET}
+Select a predefined style @var{style} (@code{c-set-style}).
@end table
- A style is a named collection of indentation customizations that can
-be used in C mode and the related modes. Emacs comes with several
+ A @dfn{style} is a named collection of customizations that can be
+used in C mode and the related modes. @ref{Styles,,, ccmode, The CC
+Mode Manual}, for a complete description. Emacs comes with several
predefined styles, including @code{gnu}, @code{k&r}, @code{bsd},
@code{stroustrup}, @code{linux}, @code{python}, @code{java},
-@code{whitesmith}, @code{ellemtel}, @code{cc-mode}, and @code{user}.
-Some of these styles are primarily intended for one language, but any
-of them can be used with any of the languages supported by these
-modes. To find out what a style looks like, select it and reindent
-some code, e.g., by typing @key{C-M-q} at the start of a function
-definition.
+@code{whitesmith}, @code{ellemtel}, and @code{awk}. Some of these
+styles are primarily intended for one language, but any of them can be
+used with any of the languages supported by these modes. To find out
+what a style looks like, select it and reindent some code, e.g., by
+typing @key{C-M-q} at the start of a function definition.
+@kindex C-c . @r{(C mode)}
@findex c-set-style
- To choose a style for the current buffer, use the command @kbd{M-x
-c-set-style}. Specify a style name as an argument (case is not
-significant). This command affects the current buffer only, and it
-affects only future invocations of the indentation commands; it does
-not reindent the code in the buffer. To reindent the whole buffer in
-the new style, you can type @kbd{C-x h C-M-\}.
+ To choose a style for the current buffer, use the command @w{@kbd{C-c
+.}}. Specify a style name as an argument (case is not significant).
+This command affects the current buffer only, and it affects only
+future invocations of the indentation commands; it does not reindent
+the code already in the buffer. To reindent the whole buffer in the
+new style, you can type @kbd{C-x h C-M-\}.
@vindex c-default-style
You can also set the variable @code{c-default-style} to specify the
-default style for various major modes. Its value should be an alist,
-in which each element specifies one major mode and which indentation
-style to use for it. For example,
+default style for various major modes. Its value should be either the
+style's name (a string) or an alist, in which each element specifies
+one major mode and which indentation style to use for it. For
+example,
@example
(setq c-default-style
- '((java-mode . "java") (other . "gnu")))
+ '((java-mode . "java") (awk-mode . "awk") (other . "gnu")))
@end example
@noindent
-specifies an explicit choice for Java mode, and the default @samp{gnu}
-style for the other C-like modes. This variable takes effect when you
-select one of the C-like major modes; thus, if you specify a new
-default style for Java mode, you can make it take effect in an
-existing Java mode buffer by typing @kbd{M-x java-mode} there.
+specifies explicit choices for Java and AWK modes, and the default
+@samp{gnu} style for the other C-like modes. (These settings are
+actually the defaults.) This variable takes effect when you select
+one of the C-like major modes; thus, if you specify a new default
+style for Java mode, you can make it take effect in an existing Java
+mode buffer by typing @kbd{M-x java-mode} there.
The @code{gnu} style specifies the formatting recommended by the GNU
Project for C; it is the default, so as to encourage use of our
recommended style.
- @xref{Customizing Indentation,,, cc-mode, the CC Mode Manual}, for
-more information on customizing indentation for C and related modes,
+ @xref{Indentation Engine Basics,,, ccmode, the CC Mode Manual}, and
+@ref{Customizing Indentation,,, ccmode, the CC Mode Manual}, for more
+information on customizing indentation for C and related modes,
including how to override parts of an existing style and how to define
your own styles.
@item C-M-f
Move forward over a balanced expression (@code{forward-sexp}).
@item C-M-b
-Move backward over a balanced expression(@code{backward-sexp}).
+Move backward over a balanced expression (@code{backward-sexp}).
@item C-M-k
Kill balanced expression forward (@code{kill-sexp}).
-@item C-M-@key{DEL}
-Kill balanced expression backward (@code{backward-kill-sexp}).
@item C-M-t
Transpose expressions (@code{transpose-sexps}).
@item C-M-@@
+@itemx C-M-@key{SPC}
Put mark after following expression (@code{mark-sexp}).
@end table
@cindex killing expressions
@kindex C-M-k
@findex kill-sexp
-@kindex C-M-DEL
-@findex backward-kill-sexp
Killing a whole balanced expression can be done with @kbd{C-M-k}
-(@code{kill-sexp}) or @kbd{C-M-@key{DEL}} (@code{backward-kill-sexp}).
-@kbd{C-M-k} kills the characters that @kbd{C-M-f} would move over, and
-@kbd{C-M-@key{DEL}} kills the characters that @kbd{C-M-b} would move
-over. On some machines, @kbd{C-M-@key{DEL}} typed on the console is a
-command to reboot; when that is so, you cannot use it as an Emacs
-command. This conflict is rare, though: usually the @key{DEL} key for
-Emacs is really @key{BACKSPACE}, and the reboot command is
-@kbd{C-M-@key{DELETE}}, so there is no conflict.
+(@code{kill-sexp}). @kbd{C-M-k} kills the characters that @kbd{C-M-f}
+would move over.
@cindex transposition of expressions
@kindex C-M-t
A somewhat random-sounding command which is nevertheless handy is
@kbd{C-M-t} (@code{transpose-sexps}), which drags the previous
balanced expression across the next one. An argument serves as a
-repeat count, and a negative argument drags the previous balanced
-expression backwards across those before it (thus canceling out the
-effect of @kbd{C-M-t} with a positive argument). An argument of zero,
-rather than doing nothing, transposes the balanced expressions ending
-at or after point and the mark.
+repeat count, moving the previous expression over that many following
+ones. A negative argument drags the previous balanced expression
+backwards across those before it (thus canceling out the effect of
+@kbd{C-M-t} with a positive argument). An argument of zero, rather
+than doing nothing, transposes the balanced expressions ending at or
+after point and the mark.
@kindex C-M-@@
+@kindex C-M-@key{SPC}
@findex mark-sexp
To set the region around the next balanced expression in the buffer,
use @kbd{C-M-@@} (@code{mark-sexp}), which sets mark at the same place
that @kbd{C-M-f} would move to. @kbd{C-M-@@} takes arguments like
@kbd{C-M-f}. In particular, a negative argument is useful for putting
-the mark at the beginning of the previous balanced expression.
+the mark at the beginning of the previous balanced expression. The
+alias @kbd{C-M-@key{SPC}} is equivalent to @kbd{C-M-@@}. When you
+repeat this command, or use it in Transient Mark mode when the mark is
+active, it extends the end of the region by one sexp each time.
In languages that use infix operators, such as C, it is not possible
to recognize all balanced expressions as such because there can be
@item C-M-n
Move forward over a parenthetical group (@code{forward-list}).
@item C-M-p
-Move backward over a parenthetical group(@code{backward-list}).
+Move backward over a parenthetical group (@code{backward-list}).
@item C-M-u
Move up in parenthesis structure (@code{backward-up-list}).
@item C-M-d
that doesn't include meaningful parentheses (symbols, strings, etc.).
@kindex C-M-u
-@kindex C-M-d
@findex backward-up-list
-@findex down-list
@kbd{C-M-n} and @kbd{C-M-p} try to stay at the same level in the
parenthesis structure. To move @emph{up} one (or @var{n}) levels, use
@kbd{C-M-u} (@code{backward-up-list}). @kbd{C-M-u} moves backward up
repeat count; a negative argument reverses the direction of motion, so
that the command moves forward and up one or more levels.
+@kindex C-M-d
+@findex down-list
To move @emph{down} in the parenthesis structure, use @kbd{C-M-d}
(@code{down-list}). In Lisp mode, where @samp{(} is the only opening
delimiter, this is nearly the same as searching for a @samp{(}. An
@vindex blink-matching-paren
@vindex blink-matching-paren-distance
@vindex blink-matching-delay
- Three variables control parenthesis match display.
-@code{blink-matching-paren} turns the feature on or off: @code{nil}
+ Three variables control parenthesis match display:
+
+ @code{blink-matching-paren} turns the feature on or off: @code{nil}
disables it, but the default is @code{t} to enable match display.
@code{blink-matching-delay} says how many seconds to leave the
that case, because the cursor appears on top of that character.) Use
the command @kbd{M-x show-paren-mode} to enable or disable this mode.
- By default, @code{show-paren-mode} uses colors to highlight the
-parentheses. However, if your display doesn't support colors, you can
-customize the faces @code{show-paren-match-face} and
-@code{show-paren-mismatch-face} to use other attributes, such as bold or
-underline. @xref{Face Customization}.
+ Show Paren mode uses the faces @code{show-paren-match} and
+@code{show-paren-mismatch} to highlight parentheses; you can customize
+them to control how highlighting looks. @xref{Face Customization}.
@node Comments
@section Manipulating Comments
@cindex comments
Because comments are such an important part of programming, Emacs
-provides special commands for editing and inserting comments.
+provides special commands for editing and inserting comments. It can
+also do spell checking on comments with Flyspell Prog mode
+(@pxref{Spelling}).
@menu
-* Comment Commands:: Inserting, killing, and indenting comments.
+* Comment Commands:: Inserting, killing, and aligning comments.
* Multi-Line Comments:: Commands for adding and editing multi-line comments.
* Options for Comments::Customizing the comment features.
@end menu
@node Comment Commands
@subsection Comment Commands
@cindex indentation for comments
+@cindex alignment for comments
The comment commands in this table insert, kill and align comments.
They are described in this section and following sections.
-@table @kbd
-@item M-;
+@table @asis
+@item @kbd{M-;}
Insert or realign comment on current line; alternatively, comment or
uncomment the region (@code{comment-dwim}).
-@item C-u M-;
+@item @kbd{C-u M-;}
Kill comment on current line (@code{comment-kill}).
-@item C-x ;
+@item @kbd{C-x ;}
Set comment column (@code{comment-set-column}).
-@item C-M-j
+@item @kbd{C-M-j}
+@itemx @kbd{M-j}
Like @key{RET} followed by inserting and aligning a comment
-(@code{comment-indent-new-line}).
-@item M-x comment-region
+(@code{comment-indent-new-line}). @xref{Multi-Line Comments}.
+@item @kbd{M-x comment-region}
+@itemx @kbd{C-c C-c} (in C-like modes)
Add or remove comment delimiters on all the lines in the region.
@end table
start with (the value of @code{comment-start}; see below). Point is
after that string, so you can insert the text of the comment right
away. If the major mode has specified a string to terminate comments,
-@kbd{M-;} inserts that too, to keep the syntax valid.
+@kbd{M-;} inserts that after point, to keep the syntax valid.
- If the text of the line extends past the comment column, then the
-comment start string is indented to a suitable boundary (usually, at
-least one space is inserted).
+ If the text of the line extends past the comment column, this
+command aligns the comment start string to a suitable boundary
+(usually, at least one space is inserted).
You can also use @kbd{M-;} to align an existing comment. If a line
-already contains the comment-start string, @kbd{M-;} reindents it to
+already contains the comment-start string, @kbd{M-;} realigns it to
the conventional alignment and moves point after it. (Exception:
comments starting in column 0 are not moved.) Even when an existing
comment is properly aligned, @kbd{M-;} is still useful for moving
is a comment, it removes comment delimiters from each; otherwise, it
adds comment delimiters to each.) If you are not using Transient Mark
mode, then you should use the commands @code{comment-region} and
-@code{uncomment-region} to do these jobs (@pxref{Multi-Line Comments}).
+@code{uncomment-region} to do these jobs (@pxref{Multi-Line Comments}),
+or else enable Transient Mark mode momentarily (@pxref{Momentary Mark}).
A prefix argument used in these circumstances specifies how many
comment delimiters to add or how many to delete.
- Some major modes have special rules for indenting certain kinds of
+ Some major modes have special rules for aligning certain kinds of
comments in certain contexts. For example, in Lisp code, comments which
start with two semicolons are indented as if they were lines of code,
instead of at the comment column. Comments which start with three
(1+ x)) ; This line adds one.
@end example
- In C code, a comment preceded on its line by nothing but whitespace
-is indented like a line of code.
+ For C-like modes, you can configure the exact effect of @kbd{M-;}
+more flexibly than for most buffers by setting the variables
+@code{c-indent-comment-alist} and
+@code{c-indent-comments-syntactically-p}. For example, on a line
+ending in a closing brace, @kbd{M-;} puts the comment one space after
+the brace rather than at @code{comment-column}. For full details see
+@ref{Comment Commands,,, ccmode, The CC Mode Manual}.
@node Multi-Line Comments
@subsection Multiple Lines of Comments
@kindex C-M-j
+@kindex M-j
@cindex blank lines in programs
@findex comment-indent-new-line
- If you are typing a comment and wish to continue it on another line,
-you can use the command @kbd{C-M-j} (@code{comment-indent-new-line}).
-This terminates the comment you are typing, creates a new blank line
-afterward, and begins a new comment indented under the old one. When
-Auto Fill mode is on, going past the fill column while typing a comment
-causes the comment to be continued in just this fashion. If point is
-not at the end of the line when @kbd{C-M-j} is typed, the text on
-the rest of the line becomes part of the new comment line.
+ If you are typing a comment and wish to continue it on another line,
+you can use the command @kbd{C-M-j} or @kbd{M-j}
+(@code{comment-indent-new-line}). If @code{comment-multi-line}
+(@pxref{Options for Comments}) is non-@code{nil}, it moves to a new
+line within the comment. Otherwise it closes the comment and starts a
+new comment on a new line. When Auto Fill mode is on, going past the
+fill column while typing a comment causes the comment to be continued
+in just this fashion.
+
+@kindex C-c C-c (C mode)
@findex comment-region
To turn existing lines into comment lines, use the @kbd{M-x
-comment-region} command. It adds comment delimiters to the lines that start
-in the region, thus commenting them out. With a negative argument, it
-does the opposite---it deletes comment delimiters from the lines in the
-region.
+comment-region} command (or type @kbd{C-c C-c} in C-like modes). It
+adds comment delimiters to the lines that start in the region, thus
+commenting them out. With a negative argument, it does the
+opposite---it deletes comment delimiters from the lines in the region.
With a positive argument, @code{comment-region} duplicates the last
-character of the comment start sequence it adds; the argument specifies
-how many copies of the character to insert. Thus, in Lisp mode,
-@kbd{C-u 2 M-x comment-region} adds @samp{;;} to each line. Duplicating
-the comment delimiter is a way of calling attention to the comment. It
-can also affect how the comment is indented. In Lisp, for proper
-indentation, you should use an argument of two or three, if between defuns;
-if within a defun, it must be three.
+character of the comment start sequence it adds; the argument
+specifies how many copies of the character to insert. Thus, in Lisp
+mode, @kbd{C-u 2 M-x comment-region} adds @samp{;;} to each line.
+Duplicating the comment delimiter is a way of calling attention to the
+comment. It can also affect how the comment is aligned or indented.
+In Lisp, for proper indentation, you should use an argument of two or
+three, if between defuns; if within a defun, it must be three.
+
+ You can configure C Mode such that when you type a @samp{/} at the
+start of a line in a multi-line block comment, this closes the
+comment. Enable the @code{comment-close-slash} clean-up for this.
+@xref{Clean-ups,,, ccmode, The CC Mode Manual}.
@node Options for Comments
@subsection Options Controlling Comments
@vindex comment-column
@kindex C-x ;
@findex comment-set-column
- The comment column is stored in the variable @code{comment-column}. You
-can set it to a number explicitly. Alternatively, the command @kbd{C-x ;}
-(@code{comment-set-column}) sets the comment column to the column point is
-at. @kbd{C-u C-x ;} sets the comment column to match the last comment
-before point in the buffer, and then does a @kbd{M-;} to align the
-current line's comment under the previous one.
+ The @dfn{comment column}, the column at which Emacs tries to place
+comments, is stored in the variable @code{comment-column}. You can
+set it to a number explicitly. Alternatively, the command @kbd{C-x ;}
+(@code{comment-set-column}) sets the comment column to the column
+point is at. @kbd{C-u C-x ;} sets the comment column to match the
+last comment before point in the buffer, and then does a @kbd{M-;} to
+align the current line's comment under the previous one.
The variable @code{comment-column} is per-buffer: setting the variable
in the normal fashion affects only the current buffer, but there is a
than the comment starting delimiter in the strictest sense of the word;
for example, in C mode the value of the variable is
@c This stops M-q from breaking the line inside that @code.
-@code{@w{"/\\*+ *\\|//+ *""}}, which matches extra stars and spaces
+@code{@w{"/\\*+ *\\|//+ *"}}, which matches extra stars and spaces
after the @samp{/*} itself, and accepts C++ style comments also.
(Note that @samp{\\} is needed in Lisp syntax to include a @samp{\} in
the string, which is needed to deny the first star its special meaning
-in regexp syntax. @xref{Regexps}.)
+in regexp syntax. @xref{Regexp Backslash}.)
@vindex comment-start
@vindex comment-end
When a comment command makes a new comment, it inserts the value of
@code{comment-start} to begin it. The value of @code{comment-end} is
-inserted after point, so that it will follow the text that you will insert
-into the comment. In C mode, @code{comment-start} has the value
-@w{@code{"/* "}} and @code{comment-end} has the value @w{@code{" */"}}.
+inserted after point, so that it will follow the text that you will
+insert into the comment. When @code{comment-end} is non-empty, it
+should start with a space. For example, in C mode,
+@code{comment-start} has the value @w{@code{"/* "}} and
+@code{comment-end} has the value @w{@code{" */"}}.
@vindex comment-padding
The variable @code{comment-padding} specifies how many spaces
-@code{comment-region} should insert on each line between the
-comment delimiter and the line's original text. The default is 1,
-to insert one space.
+@code{comment-region} should insert on each line between the comment
+delimiter and the line's original text. The default is 1, to insert
+one space. @code{nil} means 0. Alternatively, @code{comment-padding}
+can hold the actual string to insert.
@vindex comment-multi-line
The variable @code{comment-multi-line} controls how @kbd{C-M-j}
-(@code{indent-new-comment-line}) behaves when used inside a comment. If
-@code{comment-multi-line} is @code{nil}, as it normally is, then the
-comment on the starting line is terminated and a new comment is started
-on the new following line. If @code{comment-multi-line} is not
-@code{nil}, then the new following line is set up as part of the same
-comment that was found on the starting line. This is done by not
-inserting a terminator on the old line, and not inserting a starter on
-the new line. In languages where multi-line comments work, the choice
-of value for this variable is a matter of taste.
+(@code{indent-new-comment-line}) behaves when used inside a comment.
+Specifically, when @code{comment-multi-line} is @code{nil}, the
+command inserts a comment terminator, begins a new line, and finally
+inserts a comment starter. Otherwise it does not insert the
+terminator and starter, so it effectively continues the current
+comment across multiple lines. In languages that allow multi-line
+comments, the choice of value for this variable is a matter of taste.
+The default for this variable depends on the major mode.
@vindex comment-indent-function
The variable @code{comment-indent-function} should contain a function
-that will be called to compute the indentation for a newly inserted
+that will be called to compute the alignment for a newly inserted
comment or for aligning an existing comment. It is set differently by
various major modes. The function is called with no arguments, but with
point at the beginning of the comment, or at the end of a line if a new
@findex info-lookup-symbol
@findex info-lookup-file
-@kindex C-h C-i
- For C, Lisp, and other languages that have documentation in Info,
-you can use @kbd{C-h C-i} (@code{info-lookup-symbol}) to view the Info
-documentation for a symbol. You specify the symbol with the
+@kindex C-h S
+ For many major modes, that apply to languages that have
+documentation in Info, you can use @kbd{C-h S}
+(@code{info-lookup-symbol}) to view the Info documentation for a
+symbol used in the program. You specify the symbol with the
minibuffer; the default is the symbol appearing in the buffer at
-point.
+point. For example, in C mode this looks for the symbol in the C
+Library Manual. The command only works if the appropriate manual's
+Info files are installed.
The major mode determines where to look for documentation for the
symbol---which Info files to look in, and which indices to search.
You can also use @kbd{M-x info-lookup-file} to look for documentation
for a file name.
- This feature currently supports the modes Awk, Autoconf, Bison, C,
-Emacs Lisp, LaTeX, M4, Makefile, Octave, Perl, Scheme, and Texinfo,
-provided you have installed the relevant Info files, which are
-typically available with the appropriate GNU package.
+ If you use @kbd{C-h S} in a major mode that does not support it,
+it asks you to specify the ``symbol help mode''. You should enter
+a command such as @code{c-mode} that would select a major
+mode which @kbd{C-h S} does support.
@node Man Page
@subsection Man Page Lookup
@cindex manual page
On Unix, the main form of on-line documentation was the @dfn{manual
-page} or @dfn{man page}. In the GNU operating system, we hope to
+page} or @dfn{man page}. In the GNU operating system, we aim to
replace man pages with better-organized manuals that you can browse
with Info (@pxref{Misc Help}). This process is not finished, so it is
still useful to read manual pages.
@findex manual-entry
You can read the man page for an operating system command, library
-function, or system call, with the @kbd{M-x manual-entry} command. It
+function, or system call, with the @kbd{M-x man} command. It
runs the @code{man} program to format the man page; if the system
permits, it runs @code{man} asynchronously, so that you can keep on
editing while the page is being formatted. (On MS-DOS and MS-Windows
when @kbd{M-x manual-entry} prompts for the topic. For example, to
read the man page for the C library function @code{chmod} (as opposed
to a command of the same name), type @kbd{M-x manual-entry @key{RET}
-chmod(2) @key{RET}} (@code{chmod} is a system call, so it is in
-section @samp{2}).
+chmod(2) @key{RET}}. (@code{chmod} is a system call, so it is in
+section @samp{2}.)
@vindex Man-switches
If you do not specify a section, the results depend on how the
program.}. Unlike @kbd{M-x man}, it does not run any external
programs to format and display the man pages; instead it does the job
in Emacs Lisp, so it works on systems such as MS-Windows, where the
-@code{man} program (and the other programs it uses) are not generally
+@code{man} program (and other programs it uses) are not generally
available.
@kbd{M-x woman} prompts for a name of a manual page, and provides
pops up a window with possible candidates asking you to choose one of
them.
-@vindex woman-manpath
- By default, @kbd{M-x woman} looks for manual pages in the
-directories specified in the @code{MANPATH} environment variable. (If
-@code{MANPATH} is not set, @code{woman} uses a suitable default value,
-which can be customized.) More precisely, @code{woman} looks for
-subdirectories that match the shell wildcard pattern @file{man*} in each one
-of these directories, and tries to find the manual pages in those
-subdirectories. When first invoked, @kbd{M-x woman} converts the
-value of @code{MANPATH} to a list of directory names and stores that
-list in the @code{woman-manpath} variable. Changing the value of this
-variable is another way to control the list of directories used.
-
-@vindex woman-path
- You can also augment the list of directories searched by
-@code{woman} by setting the value of the @code{woman-path} variable.
-This variable should hold a list of specific directories which
-@code{woman} should search, in addition to those in
-@code{woman-manpath}. Unlike @code{woman-manpath}, the directories in
-@code{woman-path} are searched for the manual pages, not for
-@file{man*} subdirectories.
-
-@findex woman-find-file
- Occasionally, you might need to display manual pages that are not in
-any of the directories listed by @code{woman-manpath} and
-@code{woman-path}. The @kbd{M-x woman-find-file} command prompts for a
-name of a manual page file, with completion, and then formats and
-displays that file like @kbd{M-x woman} does.
-
-@vindex woman-dired-keys
- The first time you invoke @kbd{M-x woman}, it defines the Dired
-@kbd{W} key to run the @code{woman-find-file} command on the current
-line's file. You can disable this by setting the variable
-@code{woman-dired-keys} to @code{nil}. @xref{Dired}. In addition,
-the Tar-mode @kbd{w} key is define to invoke @code{woman-find-file} on
-the current line's archive member.
-
For more information about setting up and using @kbd{M-x woman}, see
@ref{Top, WoMan, Browse UN*X Manual Pages WithOut Man, woman, The WoMan
Manual}.
mode constantly displays in the echo area the argument list for the
function being called at point. (In other words, it finds the
function call that point is contained in, and displays the argument
-list of that function.) Eldoc mode applies in Emacs Lisp and Lisp
-Interaction modes only. Use the command @kbd{M-x eldoc-mode} to
-enable or disable this feature.
+list of that function.) If point is over a documented variable, it
+shows the first line of the variable's docstring. Eldoc mode applies
+in Emacs Lisp and Lisp Interaction modes, and perhaps a few others
+that provide special support for looking up doc strings. Use the
+command @kbd{M-x eldoc-mode} to enable or disable this feature.
@node Hideshow
@section Hideshow minor mode
@item C-c @@ C-s
Show the current block (@code{hs-show-block}).
@item C-c @@ C-c
-Either hide or show the current block (@code{hs-toggle-hiding})
+Either hide or show the current block (@code{hs-toggle-hiding}).
@item S-Mouse-2
-Either hide or show the block you click on (@code{hs-mouse-toggle-hiding})
+Either hide or show the block you click on (@code{hs-mouse-toggle-hiding}).
@item C-c @@ C-M-h
Hide all top-level blocks (@code{hs-hide-all}).
@item C-c @@ C-M-s
@vindex hs-hide-comments-when-hiding-all
@vindex hs-isearch-open
@vindex hs-special-modes-alist
- These user options exist for customizing Hideshow mode.
+ These variables exist for customizing Hideshow mode.
@table @code
@item hs-hide-comments-when-hiding-all
Non-@code{nil} says that @kbd{hs-hide-all} should hide comments too.
@item hs-isearch-open
-Specifies what kind of hidden blocks to open in Isearch mode.
-The value should be one of these four symbols.
+Specifies what kind of hidden blocks incremental search should make
+visible. The value should be one of these four symbols:
@table @code
-@item block
-Open only blocks.
+@item code
+Open only code blocks.
@item comment
Open only comments.
@item t
-Open both blocks and comments.
+Open both code blocks and comments.
@item nil
-Open neither blocks nor comments.
+Open neither code blocks nor comments.
@end table
@item hs-special-modes-alist
The character @kbd{M-@key{TAB}} runs a command to complete the
partial symbol before point against the set of meaningful symbol
names. This command inserts at point any additional characters that
-it can determine from the partial name.
+it can determine from the partial name. (If your window manager
+defines @kbd{M-@key{TAB}} to switch windows, you can type
+@kbd{@key{ESC} @key{TAB}} or @kbd{C-M-i}.)
If the partial name in the buffer has multiple possible completions
that differ in the very next character, so that it is impossible to
command @kbd{M-x glasses-mode} to enable or disable the mode in the
current buffer; you can also add @code{glasses-mode} to the mode hook
of the programming language major modes in which you normally want
-to use Glasses mode.
+to use Glasses mode.
@node Misc for Programs
@section Other Features Useful for Editing Programs
@cindex CORBA IDL mode
@cindex Objective C mode
@cindex C++ mode
+@cindex AWK mode
@cindex mode, Java
@cindex mode, C
+@cindex mode, C++
@cindex mode, Objective C
@cindex mode, CORBA IDL
@cindex mode, Pike
+@cindex mode, AWK
This section gives a brief description of the special features
-available in C, C++, Objective-C, Java, CORBA IDL, and Pike modes.
-(These are called ``C mode and related modes.'') @xref{Top, CC Mode,
-ccmode, , CC Mode}, for a more extensive description of these modes
+available in C, C++, Objective-C, Java, CORBA IDL, Pike and AWK modes.
+(These are called ``C mode and related modes.'') @xref{Top, , CC Mode,
+ccmode, CC Mode}, for a more extensive description of these modes
and their special features.
@menu
-* Motion in C:: Commands to move by C statements, etc.
-* Electric C:: Colon and other chars can automatically reindent.
-* Hungry Delete:: A more powerful DEL command.
-* Other C Commands:: Filling comments, viewing expansion of macros,
- and other neat features.
-* Comments in C:: Options for customizing comment style.
+* Motion in C:: Commands to move by C statements, etc.
+* Electric C:: Colon and other chars can automatically reindent.
+* Hungry Delete:: A more powerful DEL command.
+* Other C Commands:: Filling comments, viewing expansion of macros,
+ and other neat features.
@end menu
@node Motion in C
related modes.
@table @code
+@item M-x c-beginning-of-defun
+@itemx M-x c-end-of-defun
+@findex c-beginning-of-defun
+@findex c-end-of-defun
+Move point to the beginning or end of the current function or
+top-level definition. These are found by searching for the least
+enclosing braces. (By contrast, @code{beginning-of-defun} and
+@code{end-of-defun} search for braces in column zero.) If you are
+editing code where the opening brace of a function isn't placed in
+column zero, you may wish to bind @code{C-M-a} and @code{C-M-e} to
+these commands. @xref{Moving by Defuns}.
+
@item C-c C-u
@kindex C-c C-u @r{(C mode)}
@findex c-up-conditional
Move point back to the containing preprocessor conditional, leaving the
mark behind. A prefix argument acts as a repeat count. With a negative
argument, move point forward to the end of the containing
-preprocessor conditional. When going backwards, @code{#elif} is treated
-like @code{#else} followed by @code{#if}. When going forwards,
-@code{#elif} is ignored.@refill
+preprocessor conditional.
+
+@samp{#elif} is equivalent to @samp{#else} followed by @samp{#if}, so
+the function will stop at a @samp{#elif} when going backward, but not
+when going forward.
@item C-c C-p
@kindex C-c C-p @r{(C mode)}
argument, move backward.
@item M-a
-@kindex ESC a
+@kindex M-a (C mode)
@findex c-beginning-of-statement
Move point to the beginning of the innermost C statement
(@code{c-beginning-of-statement}). If point is already at the beginning
of a statement, move to the beginning of the preceding statement. With
prefix argument @var{n}, move back @var{n} @minus{} 1 statements.
-If point is within a string or comment, or next to a comment (only
-whitespace between them), this command moves by sentences instead of
-statements.
-
-When called from a program, this function takes three optional
-arguments: the numeric prefix argument, a buffer position limit
-(don't move back before that place), and a flag that controls whether
-to do sentence motion when inside of a comment.
+In comments or in strings which span more than one line, this command
+moves by sentences instead of statements.
@item M-e
-@kindex ESC e
+@kindex M-e (C mode)
@findex c-end-of-statement
-Move point to the end of the innermost C statement; like @kbd{M-a}
-except that it moves in the other direction (@code{c-end-of-statement}).
-
-@item M-x c-backward-into-nomenclature
-@findex c-backward-into-nomenclature
-Move point backward to beginning of a C++ nomenclature section or word.
-With prefix argument @var{n}, move @var{n} times. If @var{n} is
-negative, move forward. C++ nomenclature means a symbol name in the
-style of NamingSymbolsWithMixedCaseAndNoUnderlines; each capital letter
-begins a section or word.
-
-In the GNU project, we recommend using underscores to separate words
-within an identifier in C or C++, rather than using case distinctions.
-
-@item M-x c-forward-into-nomenclature
-@findex c-forward-into-nomenclature
-Move point forward to end of a C++ nomenclature section or word.
-With prefix argument @var{n}, move @var{n} times.
+Move point to the end of the innermost C statement or sentence; like
+@kbd{M-a} except that it moves in the other direction
+(@code{c-end-of-statement}).
@end table
@node Electric C
@subsection Electric C Characters
In C mode and related modes, certain printing characters are
-``electric''---in addition to inserting themselves, they also reindent
-the current line and may insert newlines. This feature is controlled by
-the variable @code{c-auto-newline}. The ``electric'' characters are
-@kbd{@{}, @kbd{@}}, @kbd{:}, @kbd{#}, @kbd{;}, @kbd{,}, @kbd{<},
-@kbd{>}, @kbd{/}, @kbd{*}, @kbd{(}, and @kbd{)}.
-
- Electric characters insert newlines only when the @dfn{auto-newline}
-feature is enabled (indicated by @samp{/a} in the mode line after the
-mode name). This feature is controlled by the variable
-@code{c-auto-newline}. You can turn this feature on or off with the
-command @kbd{C-c C-a}:
+@dfn{electric}---in addition to inserting themselves, they also
+reindent the current line, and optionally also insert newlines. The
+``electric'' characters are @kbd{@{}, @kbd{@}}, @kbd{:}, @kbd{#},
+@kbd{;}, @kbd{,}, @kbd{<}, @kbd{>}, @kbd{/}, @kbd{*}, @kbd{(}, and
+@kbd{)}.
+
+ You might find electric indentation inconvenient if you are editing
+chaotically indented code. If you are new to CC Mode, you might find
+it disconcerting. You can toggle electric action with the command
+@kbd{C-c C-l}; when it is enabled, @samp{/l} appears in the mode line
+after the mode name:
@table @kbd
-@item C-c C-a
-@kindex C-c C-a @r{(C mode)}
-@findex c-toggle-auto-state
-Toggle the auto-newline feature (@code{c-toggle-auto-state}). With a
-prefix argument, this command turns the auto-newline feature on if the
-argument is positive, and off if it is negative.
+@item C-c C-l
+@kindex C-c C-l @r{(C mode)}
+@findex c-toggle-electric-state
+Toggle electric action (@code{c-toggle-electric-state}). With a
+prefix argument, this command enables electric action if the argument
+is positive, disables it if it is negative.
@end table
- The colon character is electric because that is appropriate for a
-single colon. But when you want to insert a double colon in C++, the
-electric behavior of colon is inconvenient. You can insert a double
-colon with no reindentation or newlines by typing @kbd{C-c :}:
+ Electric characters insert newlines only when, in addition to the
+electric state, the @dfn{auto-newline} feature is enabled (indicated
+by @samp{/la} in the mode line after the mode name). You can turn
+this feature on or off with the command @kbd{C-c C-a}:
@table @kbd
-@item C-c :
-@kindex C-c : @r{(C mode)}
-@findex c-scope-operator
-Insert a double colon scope operator at point, without reindenting the
-line or adding any newlines (@code{c-scope-operator}).
+@item C-c C-a
+@kindex C-c C-a @r{(C mode)}
+@findex c-toggle-auto-newline
+Toggle the auto-newline feature (@code{c-toggle-auto-newline}). With a
+prefix argument, this command turns the auto-newline feature on if the
+argument is positive, and off if it is negative.
@end table
- The electric @kbd{#} key reindents the line if it appears to be the
-beginning of a preprocessor directive. This happens when the value of
-@code{c-electric-pound-behavior} is @code{(alignleft)}. You can turn
-this feature off by setting @code{c-electric-pound-behavior} to
-@code{nil}.
-
- The variable @code{c-hanging-braces-alist} controls the insertion of
-newlines before and after inserted braces. It is an association list
-with elements of the following form: @code{(@var{syntactic-symbol}
-. @var{nl-list})}. Most of the syntactic symbols that appear in
-@code{c-offsets-alist} are meaningful here as well.
-
- The list @var{nl-list} may contain either of the symbols
-@code{before} or @code{after}, or both; or it may be @code{nil}. When a
-brace is inserted, the syntactic context it defines is looked up in
-@code{c-hanging-braces-alist}; if it is found, the @var{nl-list} is used
-to determine where newlines are inserted: either before the brace,
-after, or both. If not found, the default is to insert a newline both
-before and after braces.
-
- The variable @code{c-hanging-colons-alist} controls the insertion of
-newlines before and after inserted colons. It is an association list
-with elements of the following form: @code{(@var{syntactic-symbol}
-. @var{nl-list})}. The list @var{nl-list} may contain either of the
-symbols @code{before} or @code{after}, or both; or it may be @code{nil}.
-
- When a colon is inserted, the syntactic symbol it defines is looked
-up in this list, and if found, the @var{nl-list} is used to determine
-where newlines are inserted: either before the brace, after, or both.
-If the syntactic symbol is not found in this list, no newlines are
-inserted.
-
- Electric characters can also delete newlines automatically when the
-auto-newline feature is enabled. This feature makes auto-newline more
-acceptable, by deleting the newlines in the most common cases where you
-do not want them. Emacs can recognize several cases in which deleting a
-newline might be desirable; by setting the variable
-@code{c-cleanup-list}, you can specify @emph{which} of these cases that
-should happen. The variable's value is a list of symbols, each
-describing one case for possible deletion of a newline. Here are the
-meaningful symbols, and their meanings:
-
-@table @code
-@item brace-catch-brace
-Clean up @samp{@} catch (@var{condition}) @{} constructs by placing the
-entire construct on a single line. The clean-up occurs when you type
-the @samp{@{}, if there is nothing between the braces aside from
-@code{catch} and @var{condition}.
-
-@item brace-else-brace
-Clean up @samp{@} else @{} constructs by placing the entire construct on
-a single line. The clean-up occurs when you type the @samp{@{} after
-the @code{else}, but only if there is nothing but white space between
-the braces and the @code{else}.
-
-@item brace-elseif-brace
-Clean up @samp{@} else if (@dots{}) @{} constructs by placing the entire
-construct on a single line. The clean-up occurs when you type the
-@samp{@{}, if there is nothing but white space between the @samp{@}} and
-@samp{@{} aside from the keywords and the @code{if}-condition.
-
-@item empty-defun-braces
-Clean up empty defun braces by placing the braces on the same
-line. Clean-up occurs when you type the closing brace.
-
-@item defun-close-semi
-Clean up the semicolon after a @code{struct} or similar type
-declaration, by placing the semicolon on the same line as the closing
-brace. Clean-up occurs when you type the semicolon.
-
-@item list-close-comma
-Clean up commas following braces in array and aggregate
-initializers. Clean-up occurs when you type the comma.
-
-@item scope-operator
-Clean up double colons which may designate a C++ scope operator, by
-placing the colons together. Clean-up occurs when you type the second
-colon, but only when the two colons are separated by nothing but
-whitespace.
-@end table
+ Usually the CC Mode style configures the exact circumstances in
+which Emacs inserts auto-newlines. You can also configure this
+directly. @xref{Custom Auto-newlines,,, ccmode, The CC Mode Manual}.
@node Hungry Delete
@subsection Hungry Delete Feature in C
+@cindex hungry deletion (C Mode)
- When the @dfn{hungry-delete} feature is enabled (indicated by
-@samp{/h} or @samp{/ah} in the mode line after the mode name), a single
-@key{DEL} command deletes all preceding whitespace, not just one space.
-To turn this feature on or off, use @kbd{C-c C-d}:
+ If you want to delete an entire block of whitespace at point, you
+can use @dfn{hungry deletion}. This deletes all the contiguous
+whitespace either before point or after point in a single operation.
+@dfn{Whitespace} here includes tabs and newlines, but not comments or
+preprocessor commands.
@table @kbd
+@item C-c C-@key{DEL}
+@itemx C-c @key{DEL}
+@findex c-hungry-backspace
+@kindex C-c C-@key{DEL} (C Mode)
+@kindex C-c @key{DEL} (C Mode)
+@code{c-hungry-backspace}---Delete the entire block of whitespace
+preceding point.
+
@item C-c C-d
-@kindex C-c C-d @r{(C mode)}
-@findex c-toggle-hungry-state
-Toggle the hungry-delete feature (@code{c-toggle-hungry-state}). With a
-prefix argument, this command turns the hungry-delete feature on if the
-argument is positive, and off if it is negative.
+@itemx C-c C-@key{DELETE}
+@itemx C-c @key{DELETE}
+@findex c-hungry-delete-forward
+@kindex C-c C-d (C Mode)
+@kindex C-c C-@key{DELETE} (C Mode)
+@kindex C-c @key{DELETE} (C Mode)
+@code{c-hungry-delete-forward}---Delete the entire block of whitespace
+following point.
+@end table
-@item C-c C-t
-@kindex C-c C-t @r{(C mode)}
-@findex c-toggle-auto-hungry-state
-Toggle the auto-newline and hungry-delete features, both at once
-(@code{c-toggle-auto-hungry-state}).
+ As an alternative to the above commands, you can enable @dfn{hungry
+delete mode}. When this feature is enabled (indicated by @samp{/h} in
+the mode line after the mode name), a single @key{DEL} deletes all
+preceding whitespace, not just one space, and a single @kbd{C-c C-d}
+(but @emph{not} plain @key{DELETE}) deletes all following whitespace.
+
+@table @kbd
+@item M-x c-toggle-hungry-state
+@findex c-toggle-hungry-state
+Toggle the hungry-delete feature
+(@code{c-toggle-hungry-state})@footnote{This command had the binding
+@kbd{C-c C-d} in earlier versions of Emacs. @kbd{C-c C-d} is now
+bound to @code{c-hungry-delete-forward}.}. With a prefix argument,
+this command turns the hungry-delete feature on if the argument is
+positive, and off if it is negative.
@end table
@vindex c-hungry-delete-key
@subsection Other Commands for C Mode
@table @kbd
+@item C-c C-w
+@itemx M-x c-subword-mode
+@findex c-subword-mode
+Enable (or disable) @dfn{subword mode}. In subword mode, Emacs's word
+commands then recognize upper case letters in
+@samp{StudlyCapsIdentifiers} as word boundaries. This is indicated by
+the flag @samp{/w} on the mode line after the mode name
+(e.g. @samp{C/law}). You can even use @kbd{M-x c-subword-mode} in
+non-CC Mode buffers.
+
+In the GNU project, we recommend using underscores to separate words
+within an identifier in C or C++, rather than using case distinctions.
+
+@item M-x c-context-line-break
+@findex c-context-line-break
+This command inserts a line break and indents the new line in a manner
+appropriate to the context. In normal code, it does the work of
+@kbd{C-j} (@code{newline-and-indent}), in a C preprocessor line it
+additionally inserts a @samp{\} at the line break, and within comments
+it's like @kbd{M-j} (@code{c-indent-new-comment-line}).
+
+@code{c-context-line-break} isn't bound to a key by default, but it
+needs a binding to be useful. The following code will bind it to
+@kbd{C-j}. We use @code{c-initialization-hook} here to make sure
+the keymap is loaded before we try to change it.
+
+@example
+(defun my-bind-clb ()
+ (define-key c-mode-base-map "\C-j" 'c-context-line-break))
+(add-hook 'c-initialization-hook 'my-bind-clb)
+@end example
+
@item C-M-h
Put mark at the end of a function definition, and put point at the
beginning (@code{c-mark-function}).
@findex c-show-syntactic-information
@kindex C-c C-s @r{(C mode)}
Display the syntactic information about the current source line
-(@code{c-show-syntactic-information}). This is the information that
-directs how the line is indented.
+(@code{c-show-syntactic-information}). This information directs how
+the line is indented.
@item M-x cwarn-mode
@itemx M-x global-cwarn-mode
@findex cwarn-mode
@findex global-cwarn-mode
+@vindex global-cwarn-mode
@cindex CWarn mode
@cindex suspicious constructions in C, C++
CWarn minor mode highlights certain suspicious C and C++ constructions:
names.
@end table
-@node Comments in C
-@subsection Comments in C Modes
-
- C mode and related modes use a number of variables for controlling
-comment format.
-
-@table @code
-@item c-comment-only-line-offset
-@vindex c-comment-only-line-offset
-Extra offset for line which contains only the start of a comment. It
-can be either an integer or a cons cell of the form
-@code{(@var{non-anchored-offset} . @var{anchored-offset})}, where
-@var{non-anchored-offset} is the amount of offset given to
-non-column-zero anchored comment-only lines, and @var{anchored-offset}
-is the amount of offset to give column-zero anchored comment-only lines.
-Just an integer as value is equivalent to @code{(@var{val} . 0)}.
-
-@item c-comment-start-regexp
-@vindex c-comment-start-regexp
-This buffer-local variable specifies how to recognize the start of a comment.
-
-@item c-hanging-comment-ender-p
-@vindex c-hanging-comment-ender-p
-If this variable is @code{nil}, @code{c-fill-paragraph} leaves the
-comment terminator of a block comment on a line by itself. The default
-value is @code{t}, which puts the comment-end delimiter @samp{*/} at the
-end of the last line of the comment text.
-
-@item c-hanging-comment-starter-p
-@vindex c-hanging-comment-starter-p
-If this variable is @code{nil}, @code{c-fill-paragraph} leaves the
-starting delimiter of a block comment on a line by itself. The default
-value is @code{t}, which puts the comment-start delimiter @samp{/*} at
-the beginning of the first line of the comment text.
-@end table
-
-@node Fortran
-@section Fortran Mode
-@cindex Fortran mode
-@cindex mode, Fortran
-
- Fortran mode provides special motion commands for Fortran statements and
-subprograms, and indentation commands that understand Fortran conventions
-of nesting, line numbers and continuation statements. Fortran mode has
-its own Auto Fill mode that breaks long lines into proper Fortran
-continuation lines.
-
- Special commands for comments are provided because Fortran comments
-are unlike those of other languages. Built-in abbrevs optionally save
-typing when you insert Fortran keywords.
-
- Use @kbd{M-x fortran-mode} to switch to this major mode. This command
-runs the hook @code{fortran-mode-hook} (@pxref{Hooks}).
-
-@cindex Fortran77 and Fortran90
-@findex f90-mode
-@findex fortran-mode
- Fortan mode is meant for editing Fortran77 ``fixed format'' source
-code. For editing the modern Fortran90 ``free format'' source code,
-use F90 mode (@code{f90-mode}). Emacs normally uses Fortran mode for
-files with extension @samp{.f}, @samp{.F} or @samp{.for}, and F90 mode
-for the extension @samp{.f90}. GNU Fortran supports both kinds of
-format.
-
-@menu
-* Motion: Fortran Motion. Moving point by statements or subprograms.
-* Indent: Fortran Indent. Indentation commands for Fortran.
-* Comments: Fortran Comments. Inserting and aligning comments.
-* Autofill: Fortran Autofill. Auto fill minor mode for Fortran.
-* Columns: Fortran Columns. Measuring columns for valid Fortran.
-* Abbrev: Fortran Abbrev. Built-in abbrevs for Fortran keywords.
-@end menu
-
-@node Fortran Motion
-@subsection Motion Commands
-
- In addition to the normal commands for moving by and operating on
-``defuns'' (Fortran subprograms---functions and subroutines), Fortran
-mode provides special commands to move by statements.
-
-@table @kbd
-@kindex C-c C-n @r{(Fortran mode)}
-@findex fortran-next-statement
-@item C-c C-n
-Move to beginning of current or next statement
-(@code{fortran-next-statement}).
-
-@kindex C-c C-p @r{(Fortran mode)}
-@findex fortran-previous-statement
-@item C-c C-p
-Move to beginning of current or previous statement
-(@code{fortran-previous-statement}).
-@end table
-
-@node Fortran Indent
-@subsection Fortran Indentation
-
- Special commands and features are needed for indenting Fortran code in
-order to make sure various syntactic entities (line numbers, comment line
-indicators and continuation line flags) appear in the columns that are
-required for standard Fortran.
-
-@menu
-* Commands: ForIndent Commands. Commands for indenting and filling Fortran.
-* Contline: ForIndent Cont. How continuation lines indent.
-* Numbers: ForIndent Num. How line numbers auto-indent.
-* Conv: ForIndent Conv. Conventions you must obey to avoid trouble.
-* Vars: ForIndent Vars. Variables controlling Fortran indent style.
-@end menu
-
-@node ForIndent Commands
-@subsubsection Fortran Indentation and Filling Commands
-
-@table @kbd
-@item C-M-j
-Break the current line and set up a continuation line
-(@code{fortran-split-line}).
-@item M-^
-Join this line to the previous line (@code{fortran-join-line}).
-@item C-M-q
-Indent all the lines of the subprogram point is in
-(@code{fortran-indent-subprogram}).
-@item M-q
-Fill a comment block or statement.
-@end table
-
-@kindex C-M-q @r{(Fortran mode)}
-@findex fortran-indent-subprogram
- The key @kbd{C-M-q} runs @code{fortran-indent-subprogram}, a command
-to reindent all the lines of the Fortran subprogram (function or
-subroutine) containing point.
-
-@kindex C-M-j @r{(Fortran mode)}
-@findex fortran-split-line
- The key @kbd{C-M-j} runs @code{fortran-split-line}, which splits
-a line in the appropriate fashion for Fortran. In a non-comment line,
-the second half becomes a continuation line and is indented
-accordingly. In a comment line, both halves become separate comment
-lines.
-
-@kindex M-^ @r{(Fortran mode)}
-@kindex C-c C-d @r{(Fortran mode)}
-@findex fortran-join-line
- @kbd{M-^} or @kbd{C-c C-d} runs the command @code{fortran-join-line},
-which joins a continuation line back to the previous line, roughly as
-the inverse of @code{fortran-split-line}. The point must be on a
-continuation line when this command is invoked.
-
-@kindex M-q @r{(Fortran mode)}
-@kbd{M-q} in Fortran mode fills the comment block or statement that
-point is in. This removes any excess statement continuations.
-
-@node ForIndent Cont
-@subsubsection Continuation Lines
-@cindex Fortran continuation lines
-
-@vindex fortran-continuation-string
- Most modern Fortran compilers allow two ways of writing continuation
-lines. If the first non-space character on a line is in column 5, then
-that line is a continuation of the previous line. We call this
-@dfn{fixed format}. (In GNU Emacs we always count columns from 0.) The
-variable @code{fortran-continuation-string} specifies what character to
-put on column 5. A line that starts with a tab character followed by
-any digit except @samp{0} is also a continuation line. We call this
-style of continuation @dfn{tab format}.
-
-@vindex indent-tabs-mode @r{(Fortran mode)}
- Fortran mode can make either style of continuation line, but you
-must specify which one you prefer. The value of the variable
-@code{indent-tabs-mode} controls the choice: @code{nil} for fixed
-format, and non-@code{nil} for tab format. You can tell which style
-is presently in effect by the presence or absence of the string
-@samp{Tab} in the mode line.
-
- If the text on a line starts with the conventional Fortran
-continuation marker @samp{$}, or if it begins with any non-whitespace
-character in column 5, Fortran mode treats it as a continuation line.
-When you indent a continuation line with @key{TAB}, it converts the line
-to the current continuation style. When you split a Fortran statement
-with @kbd{C-M-j}, the continuation marker on the newline is created
-according to the continuation style.
-
- The setting of continuation style affects several other aspects of
-editing in Fortran mode. In fixed format mode, the minimum column
-number for the body of a statement is 6. Lines inside of Fortran
-blocks that are indented to larger column numbers always use only the
-space character for whitespace. In tab format mode, the minimum
-column number for the statement body is 8, and the whitespace before
-column 8 must always consist of one tab character.
-
-@vindex fortran-tab-mode-default
-@vindex fortran-analyze-depth
- When you enter Fortran mode for an existing file, it tries to deduce the
-proper continuation style automatically from the file contents. The first
-line that begins with either a tab character or six spaces determines the
-choice. The variable @code{fortran-analyze-depth} specifies how many lines
-to consider (at the beginning of the file); if none of those lines
-indicates a style, then the variable @code{fortran-tab-mode-default}
-specifies the style. If it is @code{nil}, that specifies fixed format, and
-non-@code{nil} specifies tab format.
-
-@node ForIndent Num
-@subsubsection Line Numbers
-
- If a number is the first non-whitespace in the line, Fortran
-indentation assumes it is a line number and moves it to columns 0
-through 4. (Columns always count from 0 in GNU Emacs.)
-
-@vindex fortran-line-number-indent
- Line numbers of four digits or less are normally indented one space.
-The variable @code{fortran-line-number-indent} controls this; it
-specifies the maximum indentation a line number can have. Line numbers
-are indented to right-justify them to end in column 4 unless that would
-require more than this maximum indentation. The default value of the
-variable is 1.
-
-@vindex fortran-electric-line-number
- Simply inserting a line number is enough to indent it according to
-these rules. As each digit is inserted, the indentation is recomputed.
-To turn off this feature, set the variable
-@code{fortran-electric-line-number} to @code{nil}. Then inserting line
-numbers is like inserting anything else.
-
-@node ForIndent Conv
-@subsubsection Syntactic Conventions
-
- Fortran mode assumes that you follow certain conventions that simplify
-the task of understanding a Fortran program well enough to indent it
-properly:
-
-@itemize @bullet
-@item
-Two nested @samp{do} loops never share a @samp{continue} statement.
-
-@item
-Fortran keywords such as @samp{if}, @samp{else}, @samp{then}, @samp{do}
-and others are written without embedded whitespace or line breaks.
-
-Fortran compilers generally ignore whitespace outside of string
-constants, but Fortran mode does not recognize these keywords if they
-are not contiguous. Constructs such as @samp{else if} or @samp{end do}
-are acceptable, but the second word should be on the same line as the
-first and not on a continuation line.
-@end itemize
-
-@noindent
-If you fail to follow these conventions, the indentation commands may
-indent some lines unaesthetically. However, a correct Fortran program
-retains its meaning when reindented even if the conventions are not
-followed.
-
-@node ForIndent Vars
-@subsubsection Variables for Fortran Indentation
-
-@vindex fortran-do-indent
-@vindex fortran-if-indent
-@vindex fortran-structure-indent
-@vindex fortran-continuation-indent
-@vindex fortran-check-all-num@dots{}
-@vindex fortran-minimum-statement-indent@dots{}
- Several additional variables control how Fortran indentation works:
-
-@table @code
-@item fortran-do-indent
-Extra indentation within each level of @samp{do} statement (default 3).
-
-@item fortran-if-indent
-Extra indentation within each level of @samp{if} statement (default 3).
-This value is also used for extra indentation within each level of the
-Fortran 90 @samp{where} statement.
-
-@item fortran-structure-indent
-Extra indentation within each level of @samp{structure}, @samp{union}, or
-@samp{map} statements (default 3).
-
-@item fortran-continuation-indent
-Extra indentation for bodies of continuation lines (default 5).
-
-@item fortran-check-all-num-for-matching-do
-If this is @code{nil}, indentation assumes that each @samp{do} statement
-ends on a @samp{continue} statement. Therefore, when computing
-indentation for a statement other than @samp{continue}, it can save time
-by not checking for a @samp{do} statement ending there. If this is
-non-@code{nil}, indenting any numbered statement must check for a
-@samp{do} that ends there. The default is @code{nil}.
-
-@item fortran-blink-matching-if
-If this is @code{t}, indenting an @samp{endif} statement moves the
-cursor momentarily to the matching @samp{if} statement to show where it
-is. The default is @code{nil}.
-
-@item fortran-minimum-statement-indent-fixed
-Minimum indentation for fortran statements when using fixed format
-continuation line style. Statement bodies are never indented less than
-this much. The default is 6.
-
-@item fortran-minimum-statement-indent-tab
-Minimum indentation for fortran statements for tab format continuation line
-style. Statement bodies are never indented less than this much. The
-default is 8.
-@end table
-
-@node Fortran Comments
-@subsection Fortran Comments
-
- The usual Emacs comment commands assume that a comment can follow a line
-of code. In Fortran, the standard comment syntax requires an entire line
-to be just a comment. Therefore, Fortran mode replaces the standard Emacs
-comment commands and defines some new variables.
-
- Fortran mode can also handle the Fortran90 comment syntax where comments
-start with @samp{!} and can follow other text. Because only some Fortran77
-compilers accept this syntax, Fortran mode will not insert such comments
-unless you have said in advance to do so. To do this, set the variable
-@code{comment-start} to @samp{"!"} (@pxref{Variables}).
-
-@table @kbd
-@item M-;
-Align comment or insert new comment (@code{fortran-comment-indent}).
-
-@item C-x ;
-Applies to nonstandard @samp{!} comments only.
-
-@item C-c ;
-Turn all lines of the region into comments, or (with argument) turn them back
-into real code (@code{fortran-comment-region}).
-@end table
-
- @kbd{M-;} in Fortran mode is redefined as the command
-@code{fortran-comment-indent}. Like the usual @kbd{M-;} command, this
-recognizes any kind of existing comment and aligns its text appropriately;
-if there is no existing comment, a comment is inserted and aligned. But
-inserting and aligning comments are not the same in Fortran mode as in
-other modes.
-
- When a new comment must be inserted, if the current line is blank, a
-full-line comment is inserted. On a non-blank line, a nonstandard @samp{!}
-comment is inserted if you have said you want to use them. Otherwise a
-full-line comment is inserted on a new line before the current line.
-
- Nonstandard @samp{!} comments are aligned like comments in other
-languages, but full-line comments are different. In a standard full-line
-comment, the comment delimiter itself must always appear in column zero.
-What can be aligned is the text within the comment. You can choose from
-three styles of alignment by setting the variable
-@code{fortran-comment-indent-style} to one of these values:
-
-@vindex fortran-comment-indent-style
-@vindex fortran-comment-line-extra-indent
-@table @code
-@item fixed
-Align the text at a fixed column, which is the sum of
-@code{fortran-comment-line-extra-indent} and the minimum statement
-indentation. This is the default.
-
-The minimum statement indentation is
-@code{fortran-minimum-statement-indent-fixed} for fixed format
-continuation line style and @code{fortran-minimum-statement-indent-tab}
-for tab format style.
-
-@item relative
-Align the text as if it were a line of code, but with an additional
-@code{fortran-comment-line-extra-indent} columns of indentation.
-
-@item nil
-Don't move text in full-line comments automatically at all.
-@end table
-
-@vindex fortran-comment-indent-char
- In addition, you can specify the character to be used to indent within
-full-line comments by setting the variable
-@code{fortran-comment-indent-char} to the single-character string you want
-to use.
-
-@vindex comment-line-start
-@vindex comment-line-start-skip
- Fortran mode introduces two variables @code{comment-line-start} and
-@code{comment-line-start-skip}, which play for full-line comments the same
-roles played by @code{comment-start} and @code{comment-start-skip} for
-ordinary text-following comments. Normally these are set properly by
-Fortran mode, so you do not need to change them.
-
- The normal Emacs comment command @kbd{C-x ;} has not been redefined. If
-you use @samp{!} comments, this command can be used with them. Otherwise
-it is useless in Fortran mode.
-
-@kindex C-c ; @r{(Fortran mode)}
-@findex fortran-comment-region
-@vindex fortran-comment-region
- The command @kbd{C-c ;} (@code{fortran-comment-region}) turns all the
-lines of the region into comments by inserting the string @samp{C$$$} at
-the front of each one. With a numeric argument, it turns the region
-back into live code by deleting @samp{C$$$} from the front of each line
-in it. The string used for these comments can be controlled by setting
-the variable @code{fortran-comment-region}. Note that here we have an
-example of a command and a variable with the same name; these two uses
-of the name never conflict because in Lisp and in Emacs it is always
-clear from the context which one is meant.
-
-@node Fortran Autofill
-@subsection Fortran Auto Fill Mode
-
- Fortran Auto Fill mode is a minor mode which automatically splits
-Fortran statements as you insert them when they become too wide.
-Splitting a statement involves making continuation lines using
-@code{fortran-continuation-string} (@pxref{ForIndent Cont}). This
-splitting happens when you type @key{SPC}, @key{RET}, or @key{TAB}, and
-also in the Fortran indentation commands.
-
-@findex fortran-auto-fill-mode
- @kbd{M-x fortran-auto-fill-mode} turns Fortran Auto Fill mode on if it
-was off, or off if it was on. This command works the same as @kbd{M-x
-auto-fill-mode} does for normal Auto Fill mode (@pxref{Filling}). A
-positive numeric argument turns Fortran Auto Fill mode on, and a
-negative argument turns it off. You can see when Fortran Auto Fill mode
-is in effect by the presence of the word @samp{Fill} in the mode line,
-inside the parentheses. Fortran Auto Fill mode is a minor mode, turned
-on or off for each buffer individually. @xref{Minor Modes}.
-
-@vindex fortran-break-before-delimiters
- Fortran Auto Fill mode breaks lines at spaces or delimiters when the
-lines get longer than the desired width (the value of @code{fill-column}).
-The delimiters that Fortran Auto Fill mode may break at are @samp{,},
-@samp{'}, @samp{+}, @samp{-}, @samp{/}, @samp{*}, @samp{=}, and @samp{)}.
-The line break comes after the delimiter if the variable
-@code{fortran-break-before-delimiters} is @code{nil}. Otherwise (and by
-default), the break comes before the delimiter.
-
- By default, Fortran Auto Fill mode is not enabled. If you want this
-feature turned on permanently, add a hook function to
-@code{fortran-mode-hook} to execute @code{(fortran-auto-fill-mode 1)}.
-@xref{Hooks}.
-
-@node Fortran Columns
-@subsection Checking Columns in Fortran
-
-@table @kbd
-@item C-c C-r
-Display a ``column ruler'' momentarily above the current line
-(@code{fortran-column-ruler}).
-@item C-c C-w
-Split the current window horizontally temporarily so that it is 72
-columns wide (@code{fortran-window-create-momentarily}). This may
-help you avoid making lines longer than the 72-character limit that
-some Fortran compilers impose.
-@item C-u C-c C-w
-Split the current window horizontally so that it is 72 columns wide
-(@code{fortran-window-create}). You can then continue editing.
-@item M-x fortran-strip-sequence-nos
-Delete all text in column 72 and beyond.
-@end table
-
-@kindex C-c C-r @r{(Fortran mode)}
-@findex fortran-column-ruler
- The command @kbd{C-c C-r} (@code{fortran-column-ruler}) shows a column
-ruler momentarily above the current line. The comment ruler is two lines
-of text that show you the locations of columns with special significance in
-Fortran programs. Square brackets show the limits of the columns for line
-numbers, and curly brackets show the limits of the columns for the
-statement body. Column numbers appear above them.
-
- Note that the column numbers count from zero, as always in GNU Emacs.
-As a result, the numbers may be one less than those you are familiar
-with; but the positions they indicate in the line are standard for
-Fortran.
-
-@vindex fortran-column-ruler-fixed
-@vindex fortran-column-ruler-tabs
- The text used to display the column ruler depends on the value of
-the variable @code{indent-tabs-mode}. If @code{indent-tabs-mode} is
-@code{nil}, then the value of the variable
-@code{fortran-column-ruler-fixed} is used as the column ruler.
-Otherwise, the variable @code{fortran-column-ruler-tab} is displayed.
-By changing these variables, you can change the column ruler display.
-
-@kindex C-c C-w @r{(Fortran mode)}
-@findex fortran-window-create-momentarily
- @kbd{C-c C-w} (@code{fortran-window-create-momentarily}) temporarily
-splits the current window horizontally, making a window 72 columns
-wide, so you can see which lines that is too long. Type a space to
-restore the normal width.
-
-@kindex C-u C-c C-w @r{(Fortran mode)}
-@findex fortran-window-create
- You can also split the window horizontally and continue editing with
-the split in place. To do this, use @kbd{C-u C-c C-w} (@code{M-x
-fortran-window-create}). By editing in this window you can
-immediately see when you make a line too wide to be correct Fortran.
-
-@findex fortran-strip-sequence-nos
- The command @kbd{M-x fortran-strip-sequence-nos} deletes all text in
-column 72 and beyond, on all lines in the current buffer. This is the
-easiest way to get rid of old sequence numbers.
-
-@node Fortran Abbrev
-@subsection Fortran Keyword Abbrevs
-
- Fortran mode provides many built-in abbrevs for common keywords and
-declarations. These are the same sort of abbrev that you can define
-yourself. To use them, you must turn on Abbrev mode. @xref{Abbrevs}.
-
- The built-in abbrevs are unusual in one way: they all start with a
-semicolon. You cannot normally use semicolon in an abbrev, but Fortran
-mode makes this possible by changing the syntax of semicolon to ``word
-constituent.''
-
- For example, one built-in Fortran abbrev is @samp{;c} for
-@samp{continue}. If you insert @samp{;c} and then insert a punctuation
-character such as a space or a newline, the @samp{;c} expands automatically
-to @samp{continue}, provided Abbrev mode is enabled.@refill
-
- Type @samp{;?} or @samp{;C-h} to display a list of all the built-in
-Fortran abbrevs and what they stand for.
-
@node Asm Mode
@section Asm Mode
The variable @code{asm-comment-char} specifies which character
starts comments in assembler syntax.
+
+@ifnottex
+@include fortran-xtra.texi
+@end ifnottex
+
+@ignore
+ arch-tag: c7ee7409-40a4-45c7-bfb7-ae7f2c74d0c0
+@end ignore