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If none of the built-in styles is appropriate, you’ll probably want to
create a new 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 c-add-style
. You can see an example of a style
definition in Sample .emacs File.
([base-style] [(variable . value) …])
Optional base-style, if present, must be a string which is the name of the base style from which this style inherits. At most one base-style is allowed in a style definition. If base-style is not specified, the style inherits from the table of factory default values21 instead. All styles eventually inherit from this internal table. Style loops generate errors. The list of pre-existing styles can be seen in Built-in Styles.
The dotted pairs (variable . value) each consist of a variable and the value it is to be set to when the style is later activated.22 The variable can be either a CC Mode style variable or an arbitrary Emacs variable. In the latter case, it is not made buffer-local by the CC Mode style system.
Two variables are treated specially in the dotted pair list:
c-offsets-alist
The value is in turn a list of dotted pairs of the form
(syntactic-symbol . offset)
as described in c-offsets-alist. These are passed to
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.
c-special-indent-hook
The value is added to c-special-indent-hook
using
add-hook
, so any functions already on it are kept. If the value
is a list, each element of the list is added with add-hook
.
Styles are kept in the c-style-alist
variable, but you
should never modify this variable directly. Instead, CC Mode
provides the function c-add-style
for this purpose.
Add or update a style called stylename, a string.
description is the new style definition in the form described
above. If stylename already exists in c-style-alist
then
it is replaced by description. (Note, this replacement is
total. The old style is not merged into the new one.)
Otherwise, a new style is added.
If the optional set-p is non-nil
then the new style is
applied to the current buffer as well. The use of this facility is
deprecated and it might be removed from CC Mode in a future release.
You should use c-set-style
instead.
The sample .emacs file provides a concrete example of how a new style can be added and automatically set. See Sample .emacs File.
This is the variable that holds the definitions for the styles. It
should not be changed directly; use c-add-style
instead.
This table is stored internally in the variable c-fallback-style.
Note that if the variable has been given a value
by the Customization interface or a setq
at the top level of
your .emacs, this value will override the one the style system
tries to give it. See Config Basics.
Next: Guessing the Style, Previous: Choosing a Style, Up: Styles [Index]