On Aug 1, 2010, at 8:05 PM, Todd O'Bryan wrote: > In a language with typing and > overloading, you could define two distance functions, one that takes > two posns and another that takes four numbers, and I think this would > be the most natural way to write distance.
Like this: (define distance (case-lambda ((p q) (distance (posn-x p) (posn-x q) (posn-y p) (posn-y q))) ((x0 y0 x1 y1) (sqrt (+ (sqr (- x0 y0)) (sqr (- x1 y1))))))) (distance (posn 3 4) (posn 0 0)) _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
