#### 3.4.3 Specialized Lambda Lists

A specialized lambda list is used to specialize a method for a particular signature and to describe how arguments matching that signature are received by the method. The defined names in Figure 3–15 use specialized lambda lists in some way; see the dictionary entry for each for information about how.

      defmethod  defgeneric

      Figure 3–15: Standardized Operators that use Specialized Lambda Lists

A specialized lambda list can contain the lambda list keywords shown in Figure 3–16.

      &allow-other-keys  &key       &rest
      &aux               &optional

      Figure 3–16: Lambda List Keywords used by Specialized Lambda Lists

A specialized lambda list is syntactically the same as an ordinary lambda list except that each required parameter may optionally be associated with a class or object for which that parameter is specialized.

lambda-list ::=({var | (var [specializer])}* `[`&optional {var | (var [init-form [supplied-p-parameter]])}*`]` `[`&rest var`]` `[`&key {var | ({var | (keyword-name var)} [init-form [supplied-p-parameter]])}* [`&allow-other-keys`]`]` `[`&aux {var | (var [init-form])}*`]`)