Syntax:
(setf (slot-value-using-class (class standard-class) object (slot standard-effective-slot-defintion)) new-value)
Description:
This is a method on the generic function (setf slot-value-using-class).
This method implements the full behavior of this generic function for slots with allocation :instance and :class. If the supplied slot has an allocation other than :instance or :class an error is signaled.
Overriding this method is permitted, but may require overriding other methods in the standard implementation of the slot access protocol.