anchor.diff:  
   ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
   ;;;
  +;;; Class standard-class.
  +;;;
  +;;; Just as with STANDARD-DIRECT-SLOT-DEFININTION, ... 
  +;;; FIXME: explain more.
  +
  +(defparameter *class-standard-class*
  +  (let ((class (allocate-standard-instance nil nil)))
  +    (setf (find-class 'standard-class) class)
  +    class))
  +    
  +;;; REMEMBER: Fill in standard-class. +
  +
  +;;; We cheat by creating a list of descriptions (name and one initarg)
  +;;; of the direct slots that we know we would en up with if we had
  +;;; used the normal machinery to create the class. 
  +
  +(defparameter *standard-class-slots*
  +  '(;; Inherited from standard-object.  This information is what
  +    ;; allows us to update instances when a class changes. 
  +    (%version-information :version-information)
  +    (%name :name)
  +    (%direct-superclasses :direct-superclasses)
  +    (%direct-slots)
  +    (%direct-subclasses)
  +    (%class-precedence-list)
  +    (%effective-slot-definitions)))
  +
  +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  +;;;
  +;;; Function make-instance.  
  +;;;
  +;;; For now, we only need MAKE-INSTANCE to make instances of
  +;;; STANDARD-CLASS, which is fortunate because we don't have the
  +;;; mechanisms in place to implement MAKE-INSTANCE correctly.  So we
  +;;; temporarily define it as an ordinary function, and check that it
  +;;; is only used to define instances of STANDARD-CLASS.
  +
  +(defun make-instance (class-name
  +		      &key
  +			direct-superclasses
  +		      &allow-other-keys)
  +  nil)
  +
  +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  +;;;
   ;;; Functions ensure-class-using-class and ensure-class.  
   
   ;;; Since we don't have generic functions yet, we define
  
positive.code: ;; 				     &allow-other-keys)
  ;;   nil)
  
  (defun ensure-class (name &rest arguments &key &allow-other-keys)
    (unless (symbolp name)
      (error 'class-name-must-be-non-nil-symbol
  	   :name 'ensure-class
  	   :datum name))
  
negative.code: ;;   (initialize-instance-after-standard-class
  ;;    class direct-superclasses direct-slots))
  
  
  ;;; This fact creates a circular dependency in that standard-class
  ;;; is an instance of standard-class, so it must exist before it is
  