Bubble sort without side effects (an embarrassingly bad way of doing it)

bubble_sort.lisp

(defun my-bubble (lst)
  (or (not lst)
      (let ((ret nil) (iter nil) (small (reduce (lambda (x y) (min x y)) lst)))
    (dolist (obj lst)
      (if (not (eql obj small))
        (setf iter (cons obj iter))
        (setf ret (append ret (cons obj nil)))))
    (append ret (let ((a (my-bubble iter))) (and (listp a) a))))))
(my-bubble '(1 4 3 8 2 9))