Oh never mind I realized it’s expecting a list of predicates, not a predicate that takes a list.
But it would probably be a good thing to make it to accept a predicate too, so that you can do (listof number?). On Apr 4, 2014, at 5:44 PM, Alexander D. Knauth <alexan...@knauth.org> wrote: > I wanted to try it out, but it’s giving me an error about car expecting a > pair: > > . . car: contract violation > expected: pair? > given: #<flat-contract: (listof vector?)> > > #lang racket > > (require (submod def-multi/def-multi multim)) > (require plot/utils) > (require (only-in racket [+ rkt:+])) > (require rackunit) > > (def-multi +) > > (add-multi + '() (lambda () 0)) > (add-multi + (listof number?) (lambda args (apply + args))) > (add-multi + (listof vector?) (lambda args (apply v+ args))) > > (check-equal? (+ 1 2 3) 6) > (check-equal? (+ (vector 1 2 3) > (vector 2 3 4) > (vector 3 4 5)) > (vector 6 9 12)) > > > > On Apr 4, 2014, at 11:23 AM, Patrick Useldinger <uselpa.l...@gmail.com> wrote: > >> On 02/04/2014 20:48, Patrick Useldinger wrote: >> >>> I can share it if you're interested, it's roughly 40 lines of code. >> >> Here's the link: https://github.com/uselpa/def-multi >> >> ____________________ >> Racket Users list: >> http://lists.racket-lang.org/users > ____________________ Racket Users list: http://lists.racket-lang.org/users
