2012/3/14 Ray Racine <[email protected]>: > I could use an assist on getting the following to type check.
The program below works. I made two changes. 1. You added `All' in the type parameter list for `struct:'. You don't need that there, and instead it was adding a third type parameter to `Cvt'. 2. There's some problem with inference and struct accessors, which makes the use of `ann' below required. I've filed that as bug 12631, and hope to fix it soon. #lang typed/racket/base (struct: (T0 T1) Cvt ([cvt : (T0 -> T1)])) (: cvt-apply (All (T0 T1) (T0 (Cvt T0 T1) -> T1))) (define (cvt-apply value cvt) ((ann (Cvt-cvt cvt) (T0 -> T1)) value)) (: ItoS-Convert (Cvt Integer String)) (define ItoS-Convert (Cvt (λ: ((x : Integer)) "Hello"))) (: ItoS (Integer -> String)) (define (ItoS int) (cvt-apply int ItoS-Convert)) -- sam th [email protected] ____________________ Racket Users list: http://lists.racket-lang.org/users
