小保哥

摘要： 又叫static scope，或直观点叫bag。一个袋子，里面的环境等等都在这个袋子里。(define bank-account (let ((balance 10)) (lambda (n) (set! balance (+ balance n)) balance)))(bank-account 20) ; donating 20 dollars ;Value... 阅读全文

摘要： (define (non-number-value-error x) (display "Value error: ") (display x) (display " is not number.") (newline) 'error)(define (kproduct ls k k-value-error) (let ((break k)) (let loop ((ls ls... 阅读全文

摘要： (define (return x) x)(define (k+ a b k) (k (+ a b)))(define (kfact n k) (if (= n 1) (k 1) (kfact (- n 1) (lambda (x) (k (* n x))))))(kfact 4 (lambda (x) (k+ x 3 return)))=>(kfact 3 (lambda ... 阅读全文