class-of object → class

object — an object.

class — a class object.

Returns the class of which the object is a direct instance.

(class-of 'fred) → #<BUILT-IN-CLASS SYMBOL 610327300> 
(class-of 2/3) → #<BUILT-IN-CLASS RATIO 610326642> 

(defclass book () ()) → #<STANDARD-CLASS BOOK 33424745> 
(class-of (make-instance 'book)) → #<STANDARD-CLASS BOOK 33424745> 

(defclass novel (book) ()) → #<STANDARD-CLASS NOVEL 33424764> 
(class-of (make-instance 'novel)) → #<STANDARD-CLASS NOVEL 33424764> 

(defstruct kons kar kdr) → KONS 
(class-of (make-kons :kar 3 :kdr 4)) → #<STRUCTURE-CLASS KONS 250020317>

make-instance, type-of