[Openmcl-devel] mop issue

marco mb at bese.it
Sat Oct 2 06:41:19 PDT 2004

i originally thought this was a miss understanding on my part, but
sbcl and cmucl both deal with this code without a hitch.

(in-package :common-lisp-user)

(defclass kclass (standard-class)

(defmethod mopp:validate-superclass ((sub kclass) (super standard-class))

(defclass super ()
  (:metaclass kclass))

(defmethod mopp:compute-class-precedence-list ((class kclass))
  (let ((cpl (call-next-method))
        (super-cpl (mopp:class-precedence-list (find-class 'super))))
    (if (member (find-class 'super) cpl)
        (append (remove-if (lambda (class) (member class super-cpl)) cpl)

(defclass foo ()
  (:metaclass kclass))

(defclass bar (foo)
  (:metaclass kclass))

when attempting to define the BAR class i get an "Inconsistent
superclasses for #<KCLASS BAR>" error. i think the issue in in 
ccl::compute-cpl, but my understanding of the MOP (and in particular
openmcl's implementation) is way to weak to figure out what's wrong.

Ring the bells that still can ring.
Forget your perfect offering.
There is a crack in everything.
That's how the light gets in.
     -Leonard Cohen

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