테이블은 레코드를 바꾸고 lookup은 표현을 비공개로 남긴다.

(begin
  (define (make-table) (list '*table*))
  (define (lookup key table)
    (let ((record (assoc key (cdr table))))
      (if record (cdr record) #f)))
  (define (insert! key value table)
    (let ((record (assoc key (cdr table))))
      (if record
          (set-cdr! record value)
          (set-cdr! table
                    (cons (cons key value)
                          (cdr table)))))
    'ok)
  (define table (make-table))
  (insert! 'alpha 4 table)
  (insert! 'beta 5 table)
  (insert! 'alpha 9 table)
  (list (lookup 'alpha table)
        (lookup 'beta table)
        (lookup 'gamma table)
        table))