This type checks for me: (define-struct: (E) Arrow ([arrow : (E -> (Listof E))]))
(: compose-arrows (All (E) ((Arrow E) (Arrow E) -> (Arrow E)))) (define (compose-arrows a b) (Arrow (lambda: ((e : E)) ((Arrow-arrow a) (car ((Arrow-arrow b) e)))))) On Mon, Jul 5, 2010 at 12:19 PM, Jose A. Ortega Ruiz <[email protected]> wrote: > Is the failure to type check a genuine limitation of the type inference > engine, or is it me expecting too much from type inference in general? > And, is there a more compact way of indicating the type of that lambda? I have found that type inference doesn't work too well in lambdas w/ polymorphism. I don't know the details of the type inference algorithm. N. _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
