[racket] syntax, differently

Right. But we don't let students do that! We don't even let them use
". rest" arguments for gosh sake! :-)

Todd

On Sun, Aug 1, 2010 at 10:46 PM, Matthias Felleisen
<matthias at ccs.neu.edu> wrote:
>
> 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))
>
>
>