Specializing.
(values{!value-typespec})
[Reviewer Note by Barmar: Missing &key]
value-typespec ::={typespec}* [&optional {typespec}*] [&rest typespec] [&allow-other-keys]
| typespec | a type specifier. |
This type specifier can be used only as the value-type in a function type specifier or a the special form. It is used to specify individual types when multiple values are involved. The &optional and &rest markers can appear in the value-type list; they indicate the parameter list of a function that, when given to multiple-value-call along with the values, would correctly receive those values.
The symbol * may not be among the value-types.
The symbol values is not valid as a type specifier;
and, specifically, it is not an abbreviation for (values).