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:   "Returns OBJECT or fleeces it."
    (cond ((eq object t)
           =t=)
          ((not (sheep-p object))
           (or (find-boxed-object object)
               (values (box-object object) t)))
          (t
  
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)
  