Um, for this: (module typed typed/racket/base (provide (struct-out Foo)) (struct [A] Foo ([x : A] [y : A]) #:transparent))
(Foo "a" 'b) Should be fine because Foo could be instantiated at the type (U String Symbol). On Jan 29, 2015, at 9:25 PM, Alexis King <lexi.lam...@gmail.com> wrote: > I recently ran into a problem in which opaque types (types imported from > untyped code) cannot by parameterized by Typed Racket. I initially > encountered this problem in my attempt to port 2htdp/image to TR. > > After some further consideration, I’m interested in adding support to make > something like this possible, which would certainly have additional benefits > beyond this specific use-case. I’ve outlined my proposal here: > http://lexi-lambda.github.io/racket-parametric-opaque-types/ > > Any feedback, suggestions, or advice would be appreciated, especially from > those who are familiar with Typed Racket’s internals. > > Thank you, > Alexis > _________________________ > Racket Developers list: > http://lists.racket-lang.org/dev
_________________________ Racket Developers list: http://lists.racket-lang.org/dev