[racket] [typed racket] typing monads

Hi,

Is there a way to type a monad?

For example in OCaml:

module type MonadRequirements = sig
    type ‘a t
    val bind : ‘a t -> (‘a -> ‘b t) -> ‘b t
    val return : ‘a -> ‘a t
end;;

In Typed Racket we can use a polymorphic struct to have the parametrization by 'a and 'b, but is it possible to specify the abstract type constructor t?

Thanks,

-- Éric