스트링 리스트에서 스트링 찾기(find) with Common Lisp

[파일명:  testStringFindInList.lsp]------------------------------------------------
(defun my-find(arr s)
    (let ((k -1)
          (r -1))
        (loop for i from 0 below (length arr) do
            (setf k (search s (nth i arr)))
            (if k (progn (setf r i) (return i)))
        )
        r
    )
)

(defun printList(arr)
    (format t "[")
    (loop for i from 0 below (1- (length arr)) do
        (format t "~A, " (nth i arr))
    )
    (if (plusp (length arr))
        (format t "~A" (nth (1- (length arr)) arr))
    )
    (format t "]~%")
)

(setf words (list "하나" "둘" "셋" "넷" "다섯" "여섯"))

(format t "list: ")
(printList words)
(setf w (my-find words "셋"))
(if (>= w 0)
    (progn
        (format t "발견!  ~%")
        (format t "Next word of 셋 in list: ~A~%" (nth (1+ w) words))
    )
)

(format t "Sorting...~%")
(sort words #'string<)

(format t "list: ")
(printList words)
(setf w (my-find words "셋"))
(if (>= w 0)
    (progn
        (format t "발견!  ~%")
        (format t "Next word of 셋 in list: ~A~%" (nth (1+ w) words))
    )
)
------------------------------------------------


실행> clisp testStringFindInList.lsp
list: [하나, 둘, 셋, 넷, 다섯, 여섯]
발견!  Next word of 셋 in list: 넷
Sorting...
list: [넷, 다섯, 둘, 셋, 여섯, 하나]
발견!  Next word of 셋 in list: 여섯