anchor.diff:        (dolist (filename filenames)
   	(handler-case (delete-file directory filename)
   	  (error (e) (push filename deletions-to-retry))))
  -      deletions-to-retry)))
  +      (reverse deletions-to-retry))))
       
   (defmethod read-deletable-files ((self index-writer))
     (with-slots (directory) self
  
positive.code: 				   :term-index-interval term-index-interval)))
        (when (= (size segment-infos) 1)
  	(let ((s-reader (get-segment-reader (segment-info segment-infos 0))))
  	  (add-segment merger s-reader)
  	  (push segments-to-delete s-reader)))
        (dolist (reader readers)
  	(add-segment merger reader))
  
negative.code: 		 (dotimes (i file-count)
  		   (push (read-string input) filenames)))
  	    (close input))
  	  (reverse filenames)))))
  
  (defmethod write-deletable-files ((self index-writer) filenames)
    (with-slots (directory) self
      (let ((output (create-output directory "deleteable.new")))
        (unwind-protect
  	   (progn
  	     (write-int output (length filenames))
  	     (dolist (filename filenames)
  	       (write-string output filename)))
  	(close output)))
      (rename-file directory "deleteable.new" "deletable")))
  