(wat-aro)

生きてます

SICP 問題 3.10

(define w1 (make-withdraw 100))
;; E2(balance:100)->E1(initial-amount:100)->global

(w1 50)
;; E3->(amount:50)->E2(balance:50)->E1(initial-amount:100)->global

(define (w2 (make-withdraw 100)))
;; E5(balance:100)->E4(initial-amount:100)->global