anchor.diff:  
   (defmacro defun/cc (name arguments &body body)
     `(progn
  -     (setf (get ',name 'defun/cc) (make-instance 'closure/cc
  -                                                 :code (walk-form '(lambda ,arguments ,@body) nil nil)
  -                                                 :env nil))
  +     (setf (fdefinition ',name) (make-instance 'closure/cc
  +                                               :code (walk-form '(lambda ,arguments ,@body) nil nil)
  +                                               :env nil))
        (defun ,name ,arguments
          (declare (ignorable ,@(extract-argument-names arguments :allow-specializers nil)))
          (error "Sorry, /CC function are not callable outside of with-call/cc."))))
  
positive.code:      (evaluate-apply/cc (arguments func) '() env k))
      
      ((and (symbolp (operator func))
            (get (operator func) 'defun/cc))
       (evaluate-arguments-then-apply
        (lambda (arguments)
          (apply-lambda/cc (get (operator func) 'defun/cc) arguments k))
        (arguments func) '()
        env))
  
      ((and (symbolp (operator func))
            (get (operator func) 'defmethod/cc))
       (evaluate-arguments-then-apply
        (lambda (arguments)
          (apply-lambda/cc (apply (fdefinition (operator func)) arguments) arguments k))
        (arguments func) '()
        env))
         
  
negative.code:          (primary-value-p (funcall k primary-value))
           (t (funcall k nil)))))))
  
  (defvar *cc-functions* (make-hash-table :test 'eql))
  
  (defun fmkunbound/cc (function-name)
    (remhash function-name *cc-functions*))
  
  (defun fdefinition/cc (function-name)
    (gethash function-name *cc-functions*))
  
  (defun (setf fdefinition/cc) (closure-object function-name)
    (setf (gethash function-name *cc-functions*) closure-object))
  
  ;;;; Implementation
  
  (defun drive-interpreter/cc (code)
  