(define (point x y) (define (dispatch m) (cond ((eq? m 'getx) x) ((eq? m 'gety) y) ((eq? m 'type) 'point) ((eq? m 'info) (list 'point x y)) (else (display (string-append "point as no method: " (symbol->string m) "\n"))))) dispatch) (define p (point 1 2)) (p 'getx) ; 1 (p 'gety) ; 2 (p 'type) ; point (p 'info) ; (point 1 2) (p 'foo) ; display "point as no method: foo