-;; (define (kill-asteroids s a)
-;; (define (f1 s1 a)
-;; (cond ((null? a)
-;; (values a #f))
-;; (else
-;; (let ((a1 (car a)))
-;; (cond ((< (distance-between-points (list (assoc-ref s1 'x) (assoc-ref s1 'y))
-;; (list (assoc-ref a1 'x) (assoc-ref a1 'y)))
-;; (assoc-ref a1 'size))
-;; (values (cdr a) #t))
-;; (else
-;; (receive (an k) (f1 s1 (cdr a))
-;; (values (cons a1 an) k))))))))
-
-;; (cond ((null? s)
-;; (values s a))
-;; (else
-;; (let ((s1 (car s)))
-;; (receive (an k) (f1 s1 a)
-;; (cond (k
-;; (kill-asteroids (cdr s) an))
-;; (else
-;; (receive (sn an) (kill-asteroids (cdr s) an)
-;; (values (cons s1 sn) an)))))))))
-