Request for comments on CLOS code

From: Enrico `Trippo' Porreca (eporreca_at_people.it)
Date: 08/28/04 

Date: Sat, 28 Aug 2004 00:19:51 +0200

The following is one of my first experiments with the Common Lisp Object
System: the implementation of a FIFO queue. I'd like to hear your
comments (of any kind) about my code.

(defclass queue ()
   ((head :initform nil
          :accessor head)
    (tail :initform nil
          :accessor tail)))

(defmethod emptyp ((queue queue))
   (null (head queue)))

(defmethod enqueue (object (queue queue))
   (let ((new-tail (list object)))
     (if (emptyp queue)
         (setf (head queue) new-tail)
         (rplacd (tail queue) new-tail))
     (setf (tail queue) new-tail)))

(defmethod dequeue ((queue queue))
   (pop (head queue)))

Thanks in advance. 

-- 
Enrico `Trippo' Porreca

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