anchor.diff:    "Finds a previously-boxed object in the boxed object table.
   If ERRORP is T, this signals an error if OBJECT is a sheep, or if OBJECT
   has not already been boxed."
  -  (if (sheep-p object)
  +  (if (sheepp object)
         (if errorp (error "~S seems to already be a sheep." object) nil)
         (multiple-value-bind (sheep hasp)
             (gethash object *boxed-object-table*)
  
positive.code: 
  (defun box-object (object)
    "Wraps OBJECT with a sheep."
    (if (sheep-p object)
        (error "~S seems to already be a sheep." object)
        (setf (gethash object *boxed-object-table*)
              (defclone ((box-type-of object))
                  ((wrapped-object object)) (:nickname object)))))
  
  (defun remove-boxed-object (object)
  
negative.code: 
  (defun box-type-of (x)
    ;; Note: I should really find a way to make this simply use CLOS...
    (if (sheepp x)
        (progn
          (warn "This is already a sheep!")
          x)
  