@findex setup-paragraph-variables (c-)
Also note that since @ccmode{} uses the value of
@code{c-comment-prefix-regexp} to set up several other variables at mode
-initialization, there won't have any effect if you change it inside a
+initialization, there won't be any effect if you just change it inside a
@ccmode{} buffer. You need to call the command
-@code{c-setup-paragraph-variables} to update those other variables with
+@code{c-setup-paragraph-variables} too, to update those other variables with
the new value. That's also the case if you modify this variable in a
mode hook, since @ccmode{} sets up all variables before calling them.
@end defopt
variable@footnote{In versions before 5.26, this variable was called
@code{c-comment-continuation-stars}. As a compatibility measure,
@ccmode{} still uses the value on that variable if it's set.} is used
-then as the comment prefix. It defaults to @samp{* }, which makes a
-comment
+then as the comment prefix. It defaults to @samp{*
+}@footnote{Actually, this default setting of
+@code{c-block-comment-prefix} typically gets overriden by the default
+style @code{gnu}, which sets it to blank. You can see the line
+splitting effect described here by setting a different style,
+e.g. @code{k&r} @xref{Choosing a Style}.}, which makes a comment
@example
/* Got O(n^2) here, which is a Bad Thing. */
@cindex font locking
@comment !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
-@strong{Note:} The font locking in AWK mode is currently not integrated
+@strong{Please note:} The font locking in AWK mode is currently not integrated
with the rest of @ccmode{}, so this section does not apply there.
@xref{AWK Mode Font Locking}, instead.
@vindex tab-always-indent (c-)
@kindex TAB
@cindex literal
-This variable controls how @kbd{TAB} (@code{c-indent-command}) operates.
-When it is @code{t}, @kbd{TAB} always indents the current line. When it
-is @code{nil}, the line is indented only if point is at the left margin,
-or on or before the first non-whitespace character on the line,
-otherwise some whitespace is inserted. If this variable is the symbol
-@code{other}, then some whitespace is inserted only within strings and
-comments (literals), and inside preprocessor directives, but the line is
+This variable controls how @kbd{TAB} (@code{c-indent-command})
+operates. When it is @code{t}, @kbd{TAB} always indents the current
+line. When it is @code{nil}, the line is indented only if point is at
+the left margin, or on or before the first non-whitespace character on
+the line, otherwise some whitespace is inserted. If this variable is
+some other value (not @code{nil} or @code{t}), then some whitespace is
+inserted only within strings and comments (literals), but the line is
always reindented.
@end defopt
@comment !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
@node Adding Styles, File Styles, Choosing a Style, Styles
@comment node-name, next, previous, up
-@subsection Adding Styles
+@subsection Adding and Amending Styles
@comment !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
If none of the built-in styles is appropriate, you'll probably want to
-add a new @dfn{style definition}. Styles are kept in the
-@code{c-style-alist} variable, but you should never modify this
-variable directly. Instead, @ccmode{} provides the function
-@code{c-add-style} that you can use to easily add new styles or change
-existing styles:
+create a new @dfn{style definition}, possibly based on an existing
+style. To do this, put the new style's settings into a list with the
+following format - the list can then be passed as an argument to the
+function @code{c-add-style}:
+
+@cindex style definition
+@defvr {List} style definition
+([@var{base-style}] [(@var{variable} . @var{value}) @dots{}])
+
+Optional @var{base-style}, if present, must be a string which is the
+name of the @dfn{base style} from which this style inherits. At most
+one @var{base-style} is allowed in a style definition. If
+@var{base-style} is not specified, the style inherits from a table of
+default values@footnote{This table is stored internally in the
+variable c-fallback-style. It is computed during the initialisation
+of @ccmode{} from the factory defaults of the style variables and any
+global values they may have been given since starting Emacs.} instead.
+All styles eventually inherit from this internal table. Style loops
+generate errors. The list of pre-existing styles can be seen in
+@ref{Built-in Styles}.
+
+The dotted pairs (@var{variable} . @var{value}) each consist of a
+variable and the value it is to be set to when the style is later
+activated.@footnote{In certain circumstances, this value can get
+overridden by another value.} The variable can be either a @ccmode{}
+style variable or an arbitrary Emacs variable. In the latter case, it
+is @emph{not} made buffer local by the @ccmode{} style system.
+@end defvr
+
+Two variables are treated specially in the dotted pair list:
+
+@table @code
+@item c-offsets-alist
+The value is in turn a dotted list on the form
+
+(@var{syntactic-symbol} . @var{offset})
+
+as described in @ref{Customizing Indentation}. These are passed to
+@code{c-set-offset} so there is no need to set every syntactic symbol in
+your style, only those that are different from the inherited style.
+
+@item c-special-indent-hook
+The value is added to @code{c-special-indent-hook} using
+@code{add-hook}, so any functions already on it are kept. If the value
+is a list, each element of the list is added with @code{add-hook}.
+@end table
+
+Styles are kept in the @code{c-style-alist} variable, but you
+should never modify this variable directly. Instead, @ccmode{}
+provides the function @code{c-add-style} for this purpose.
@defun c-add-style stylename description &optional set-p
@findex add-style (c-)
-Add or update a style. If @var{stylename} is not already in
-@code{c-style-alist} then a new style according to @var{description}
-is added, otherwise the existing style is changed. If the optional
-@var{set-p} is non-@code{nil} then the new style is applied to the
-current buffer as well.
-
-@comment TBD: The next paragraph is bogus. I really need to better
-@comment document adding styles, including setting up inherited styles.
+Add or update a style called @var{stylename}, a string.
+@var{description} is the new style definition in the form described
+above. If @var{stylename} already exists in @code{c-style-alist} then
+it is replaced by @var{description}. (Note, this replacement is
+total. The old style is @emph{not} merged into the new one.)
+Otherwise, a new style is added. If the optional @var{set-p} is
+non-@code{nil} then the new style is applied to the current buffer as
+well.
The sample @file{.emacs} file provides a concrete example of how a new
style can be added and automatically set. @xref{Sample .emacs File}.
Lines continuing the header of a lambda function, i.e., between the
@code{lambda} keyword and the function body. Only used in Pike mode.
@item inexpr-statement
-A statement block inside an expression. The gcc C extension of this is
-recognized. It's also used for the special functions that takes a
-statement block as an argument in Pike.
+A statement block inside an expression. The gcc C and C++ extension for
+this is recognized. It's also used for the special functions that take
+a statement block as an argument in Pike.
@item inexpr-class
A class definition inside an expression. This is used for anonymous
classes in Java. It's also used for anonymous array initializers in
@code{inexpr-class}.
There are a few occasions where a statement block may be used inside an
-expression. One is in C code using the gcc extension for this, e.g:
+expression. One is in C or C++ code using the gcc extension for this,
+e.g:
@example
1: int res = (@{
value is an association list that for each language mode specifies the
value to give to @code{require-final-newline} at mode initialization;
see that variable for details about the value. If a language isn't
-present on the association list, CC Mode won't set
+present on the association list, CC Mode won't touch
@code{require-final-newline} in buffers for that language.
The default is to set @code{require-final-newline} to @code{t} in the
(somewhat cryptic) error message.}. If you are using the standalone
@ccmode{} distribution, try recompiling it according to the instructions
in the @file{README} file.
+
+@item
+@cindex open paren in column zero
+@emph{I have an open paren character at column zero inside a comment or
+multiline string literal, and it causes the fontification and/or
+indentation to go haywire. What gives?}
+
+It's due to the ad-hoc rule in (X)Emacs that such open parens always
+start defuns (which translates to functions, classes, namespaces or any
+other top-level block constructs in the @ccmode{} languages).
+@xref{Left Margin Paren,,, emacs, The Emacs Editor}, for details
+(@xref{Defuns,,, emacs, The Emacs Editor}, in the Emacs 20 manual).
+
+This heuristic is built into the core syntax analysis routines in
+(X)Emacs, so it's not really a @ccmode{} issue. However, in Emacs 21.4
+it has become possible to turn it off@footnote{Using the variable
+@code{open-paren-in-column-0-is-defun-start}.} and @ccmode{} does so
+there since it got its own system to keep track of blocks.
+
@end itemize