Определить функцию для циклического сдвига списка вправо на один элемент

(defun rev (lst r)
  (cond ((null lst) r)
        (t (rev (cdr lst) (cons (car lst) r)))))
 
==> REV
 
(rev '(1 2 3) nil)
==> (3 2 1)
 
(defun lrot (lst a)
  (cond ((null (cdr lst)) (cons (car lst) (rev a nil)))
        (t (lrot (cdr lst) (cons (car lst) a))))) 
 
==> LROT
 
(lrot '(1 2 3 4 5) nil)
==> (5 1 2 3 4)
 
(defun task (lst)
  (lrot lst nil))
 
==> TASK
 
(task '(1 2 3 4 5))
==> (5 1 2 3 4)

(defun shift-right-once
    (w &optional ac &aux (a (car w)) (d (cdr w)))
  (if d (shift-right-once d (cons a ac))
      (cons a (_reverse ac))))
 
(defun _reverse (w &optional ac)
  (if w (_reverse (cdr w) (cons (car w) ac)) ac))
 
> (shift-right-once '(1 2 3 4 5))
(5 1 2 3 4)

(defun shift-right-once
    (w &optional ac &aux (a (car w)) (d (cdr w)))
  (if d (shift-right-once d (cons a ac))
      (cons a (nreverse ac))))
 
> (shift-right-once '(1 2 3 4 5))
(5 1 2 3 4)

(defun shift-left (w n) 
  (append (nthcdr n w) (subseq w 0 n)))
 
> (shift-left '(1 2 3 4 5) 1)
(2 3 4 5 1)

(defun shift-right (w n) 
  (append (last w n) (butlast w n)))
 
> (shift-right '(1 2 3 4 5) 1)
(5 1 2 3 4)

(defun shift-right (w n &aux (m (if (minusp n) 0 n)))
  (append (last w m) (butlast w m)))
 
> (shift-right '(1 2 3 4 5) 1)
(5 1 2 3 4)

(defun shift-right (w n)
  ((lambda (w m) 
     (append (last w m) (butlast w m)))
   w (if (minusp n) 0 n)))
 
> (shift-right '(1 2 3 4 5) 1)
(5 1 2 3 4)

(defun shift-right (w n)
  (let ((m (if (minusp n) 0 n)))
    (append (last w m) (butlast w m))))
 
> (shift-right '(1 2 3 4 5) 1)
(5 1 2 3 4)