The customization declarations that we will describe in the next few
defgroup, etc.—all accept
keyword arguments (see Constant Variables) for specifying various
information. This section describes keywords that apply to all types
of customization declarations.
All of these keywords, except
:tag, can be used more than once
in a given item. Each use of the keyword has an independent effect.
:tag is an exception because any given item can only
display one name.
When you use
:group in a
defgroup, it makes the new
group a subgroup of group.
If you use this keyword more than once, you can put a single item into
more than one group. Displaying any of those groups will show this
item. Please don't overdo this, since the result would be annoying.
There are several alternatives you can use for link-data:
"(emacs)Top". The link appears as ‘[Manual]’ in the customization buffer and enters the built-in Info reader on info-node.
custom-manualexcept that the link appears in the customization buffer with the Info node name.
find-filewhen the user invokes this link.
describe-functionwhen the user invokes this link.
describe-variablewhen the user invokes this link.
You can specify the text to use in the customization buffer by adding
:tag name after the first element of the link-data;
(info-link :tag "foo" "(emacs)Top") makes a link to
the Emacs manual which appears in the buffer as ‘foo’.
You can use this keyword more than once, to add multiple links.
load, and only if the file is not already loaded.
)when your saved customizations set the value of this item. feature should be a symbol.
The most common reason to use
:require is when a variable enables
a feature such as a minor mode, and just setting the variable won't have
any effect unless the code which implements the mode is loaded.
package should be the official name of the package, as a symbol
MH-E). version should be a string. If the
package package is released as part of Emacs, package and
version should appear in the value of
Packages distributed as part of Emacs that use the
:package-version keyword must also update the
This alist provides a mapping for the versions of Emacs that are associated with versions of a package listed in the
:package-versionkeyword. Its elements are:(package (pversion . eversion)...)
For each package, which is a symbol, there are one or more elements that contain a package version pversion with an associated Emacs version eversion. These versions are strings. For example, the MH-E package updates this alist with the following:(add-to-list 'customize-package-emacs-version-alist '(MH-E ("6.0" . "22.1") ("6.1" . "22.1") ("7.0" . "22.1") ("7.1" . "22.1") ("7.2" . "22.1") ("7.3" . "22.1") ("7.4" . "22.1") ("8.0" . "22.1")))
The value of package needs to be unique and it needs to match the package value appearing in the
:package-versionkeyword. Since the user might see the value in an error message, a good choice is the official name of the package, such as MH-E or Gnus.