anchor.diff:    (with-accessors ((mux mux-of) (fds fds-of)
                      (timeouts timeouts-of)) event-base
       (let ((deletion-list ())
  -          (fd-events (harvest-events mux timeout)))
  +          (fd-events (harvest-events mux (or timeout *default-event-loop-timeout*))))
         (dolist (ev fd-events)
           (destructuring-bind (fd ev-types) ev
             (let ((fd-entry (fd-entry-of event-base fd)))
  
positive.code: 
  
  (defgeneric exit-event-loop (event-base &key delay)
    (:method ((event-base event-base) &key delay)
      (setf (main-timeout-of event-base)
            (add-timeout event-base
                         #'(lambda (fd event-type)
  
negative.code: 
           (queue-sort timeouts #'< #'event-abs-timeout)
  
           :when (or only-once exit-p
                     (and exit-when-empty (event-base-empty-p event-base)))
           :do (loop-finish)))))
  
  
  