#;6> (define (a* _) (list 1 2 3))
#;7> (a* 1)
(1 2 3)
#;8> (a* 2)
(1 2 3)
#;9> (set-car! (a* 1) 5)
#;10> (a* 1)
(1 2 3)
#;11> (a* 2)
(1 2 3)