평가기는 지역 초기화를 명시적인 형태로 바꿀 수 있다.

(begin
  (define body
    '((define (even-step value)
        (if (= value 0)
            #t
            (odd-step (- value 1))))
      (define (odd-step value)
        (if (= value 0)
            #f
            (even-step (- value 1))))
      (list (even-step n) (odd-step n))))
  (define (definition? expression)
    (and (pair? expression)
         (eq? (car expression) 'define)))
  (define (take-definitions expressions)
    (if (and (pair? expressions)
             (definition? (car expressions)))
        (cons (car expressions)
              (take-definitions (cdr expressions)))
        '()))
  (define (drop-definitions expressions)
    (if (and (pair? expressions)
             (definition? (car expressions)))
        (drop-definitions (cdr expressions))
        expressions))
  (define (definition-name definition)
    (if (symbol? (cadr definition))
        (cadr definition)
        (car (cadr definition))))
  (define (definition-value definition)
    (if (symbol? (cadr definition))
        (caddr definition)
        (cons 'lambda
              (cons (cdr (cadr definition))
                    (cddr definition)))))
  (define (make-binding definition)
    (list (definition-name definition)
          (list 'quote '*unassigned*)))
  (define (make-assignment definition)
    (list 'set!
          (definition-name definition)
          (definition-value definition)))
  (define (scan-out-defines expressions)
    (let ((definitions (take-definitions expressions))
          (remaining (drop-definitions expressions)))
      (if (null? definitions)
          expressions
          (list
            (cons 'let
                  (cons (map make-binding definitions)
                        (append (map make-assignment definitions)
                                remaining)))))))
  (car (scan-out-defines body)))