平方根 (define sqrt-iter (lambda (guess x guess-prev) (if (good-enough? guess guess-prev) guess (sqrt-iter (improve guess x) x guess)))) (define improve (lambda (guess x) (average guess (/ x guess)))) (define average (lambda (x y) (/ (+ x …

Scheme修行20章のインタープリタをまとめて書いてみました。以下です。 ;; utility (define atom? (lambda (x) (and (not (pair? x)) (not (null? x))))) (define add1 (lambda (x) (+ x 1))) (define sub1 (lambda (x) (- x 1))) (define name-of (lambda (…