How to use call-next-method in initialize-instance with multiple key arguments CLOS

Question

If I have two classes, a class parent and a class child.

(defclass parent ()
    ...)

(defclass child (parent)
    ...)

And I've defined 2 different methods for initialize-instance, but the child one takes another argument, and calls call-next-method

(defmethod initialize-instance :after ((instance parent) &key)
    ...) ; Do things

(defmethod initialize-instance :after ((instance child) &key other-arg)
    ... ; Do things
    (call-next-method))

I get the error

There is no next method for the generic function
#<STANDARD-METHOD COMMON-LISP:INITIALIZE-INSTANCE (93)>
when called from method
#<STANDARD-METHOD COMMON-LISP:INITIALIZE-INSTANCE :AFTER (CHILD) {...}>
with arguments
 ....

Condition of type SB-PCL::NO-NEXT-METHOD-ERROR

Apparently, I can't call the next method with the supplied arguments?

Answer 1

In the standard method combination, which is what you are using, after methods don't have next methods, so call-next-method can't be used within them: rather applicable after methods are all called in most-specific-last order by the method combination. The places you are allowed to use call-next-method are primary and around methods.

Answer 2

Could it be that you're referencing methods not mentioned in your post? The error message mentions an :after method. Perhaps you could start a fresh sbcl instance and recreate the classes and methods there, just to make sure that the same issue persists?

I tried to fill in the blanks in your code like so:

(defclass parent ()
  nil)

(defclass child (parent)
  nil)

(defmethod initialize-instance ((instance parent) &key)
  (format t "~&Init parent."))

(defmethod initialize-instance ((instance child) &key other-arg)
  (format t "Init child with ~a." other-arg)
  (call-next-method))

CL-USER> (make-instance 'parent)
Init parent.
#<PARENT {100390DEE3}>
CL-USER> (make-instance 'child)
Init child with NIL.
Init parent.
#<CHILD {100390AB93}>
CL-USER> (make-instance 'child :other-arg 'foo)
Init child with FOO.
Init parent.
#<CHILD {100396D253}>

The above seems to work in my setup.
Does it work for you?