anchor.diff:  	(open (file-name tree) :direction :io :if-exists :overwrite :if-does-not-exist :create :element-type 'character)))
   
   (defun close-storage-stream (tree)
  +  (finish-output (storage-stream tree))
     (close (storage-stream tree)))
   
   (defmethod prb-open-storage ((tree text-file-red-black-tree))
  
positive.code: 	    (location (leaf tree))))
  
  (defmethod prb-save-root ((tree text-file-red-black-tree) root)
    (close-storage-stream tree)
    (let* ((stream (open-storage-stream tree))
  	 (header (read-stored-object stream))
  	 (backup (read-stored-object stream))
  	 (last-header (last-header tree)))
      (unless (and (equality last-header header)
  
  		 (equality last-header backup))
        (close-storage-stream tree)
        (error 'inconsistent-storage)))
    (let ((header (make-storage-header tree))
  	(stream (open-storage-stream tree)))
      (file-position stream :start)
  
negative.code: 
  (defmacro form (number contents)
    `(make-instance 'storage-form 
  		   :number ,number 
  		   :contents ,contents))
  
  (defclass text-file-red-black-object (persistent-red-black-object)
    ((location :initform (make-instance 'storage-location) :initarg :location :accessor location)))
  