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ioocaml

Is there any way to print a module type without using a function in that module?

Let's say I have a module like this:

module type MyModule = 
   sig
      type t
      func1 : ... -> t
   end

(* Implementation *)
module SomeModule : MyModule = 
   struct
      type t = int
      let func1 ... : t =
         (* do something and return type t *)
      end

Now, I called func1 somewhere outside the module and obtained a value with type MyModule.t:

let x = SomeModule.func1 ... in
   print_int x   (* Which doesn't works *)

So I'm wondering is there any way to print x? Thanks for answering!

Solution

  • The short answer is "no". You've specifically made the type t abstract, so there is no way to do anything with values of type t outside SomeModule.

    There are of course sneaky ways to subvert the type system in OCaml (as in every language), but generally speaking you should avoid them like the plague.