segments->painter return is failing on being passed to paint

[ebellani@…]

;; examples of segments
(define first-segment (make-segment (make-vect 0.0 1.0)

(make-vect 2.0 3.0)))

(define second-segment (make-segment (make-vect 4.0 5.0)

(make-vect 6.0 7.0)))

(paint (segments->painter (list first-segment

second-segment)))

;; fails with:

;; for-each: expects type <proper list> as 2nd argument, given: ({{0.0 . 1.0} 2.0 . 3.0} {{3.0 . 5.0} 6.0 . 7.0}); other arguments were: #<procedure:...t/2/1/prmpnt.scm:115:7>