스트링 벡터에서 스트링 찾기(find) with Common Lisp

[파일명:  testStringFindInVector.lsp]------------------------------------------------
#!/usr/bin/env clisp

;; Filename: testStringFindInVector.lsp
;;
;;            Approximate square roots, cubic roots and n-th roots of a given number.
;;
;; Execute: clisp testStringFindInVector.lsp
;;   Or
;; Execute: ./testStringFindInVector.lsp
;;
;; Date: 2013. 9. 12.

(defun my-exact-find(arr s)
    ; (position s arr))
   (let ((r -1))
        (loop for i from 0 below (length arr) do
            (if (string= s (aref arr i))
         (progn
        (setf r i)
     (return i))))
        r))

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

(setf *words* (vector "하나" "둘" "셋" "넷" "다섯" "여섯"))
(setf where (my-exact-find *words* "셋"))

(format t "vector: ")
(printArray *words*)
; (format t "where = ~A~%" where)
(if (and where (>= where 0))
    (progn
        (format t "발견! ~%")
        (if (< where (length *words*))
            (format t "Next word of 셋 in vector: ~A~%" (aref *words* (+ where 1))))))

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

(setf where (my-exact-find *words* "셋"))
(format t "vector: ")
(printArray *words*)
(if (and where (>= where 0))
    (progn
        (format t "발견! ~%")
        (if (< where (length *words*))
            (format t "Next word of 셋 in vector: ~A~%" (aref *words* (+ where 1))))))

#|
Output:
vector: [하나, 둘, 셋, 넷, 다섯, 여섯]
발견!
Next word of 셋 in vector: 넷
Sorting...
vector: [넷, 다섯, 둘, 셋, 여섯, 하나]
발견!
Next word of 셋 in vector: 여섯
|#
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