Function: custom-add-frequent-value
custom-add-frequent-value is a for custom-add-option,
defined in custom.el.gz.
Signature
(custom-add-frequent-value SYMBOL OPTION)
Documentation
To the variable SYMBOL add OPTION.
If SYMBOL's custom type is a hook, OPTION should be a hook member. If SYMBOL's custom type is an alist, OPTION specifies a symbol to offer to the user as a possible key in the alist. For other custom types, this has no effect.