anchor.diff:          (kill-ring-nth n)))
   
   (defmacro with-kill (() &body body)
  -  `(unless *kill-disable-p*
  +  `(progn
        (when-interrupted-flag :kill
                               (setq *kill-new-flag* t))
        ,@body))
  
positive.code: 
  (defvar *kill-new-flag* t)
  (defvar *kill-before-p* nil)
  (defvar *kill-disable-p* nil)
  
  (defun kill-append (lines before-p)
    (setf (car *kill-ring*)
  
negative.code:           *kill-ring-max*
            *kill-new-flag*
            *kill-before-p*
            kill-append
            kill-push
            yank
  