Discussion on: Reason(React) Best Practices - Part 3

[Florian Hammerschmidt]

So bs.unwrap does unfortunately not work with @bs.obj. This means it also does not work with [@react.component] either, which uses @bs.obj internally, if you stumbled over that.

It works perfectly in the source code of the example which does not use @bs.obj.

If you are on BuckleScript 7.1 or higher, there is an alternative, though: [@unboxed]:

For instance if you take the callbackOrButtons from above:

type button;

module CallbackOrButtons = {
    [@unboxed] 
    type t =
        | Any('a): t;

    let makeCallback: (. string => unit) => t = (. s) => Any(s);
    let makeButtons: array(button) => t = i => Any(i);
};

/* The Obj.magic is only for demonstration purposes, 
   I did not want to type out the button type. */
let buttons = CallbackOrButtons.makeButtons([|"<Button/>"->Obj.magic|])
let callback = CallbackOrButtons.makeCallback(. a => Js.log(a))

then you would call ~callbackOrButtons=buttons or ~callbackOrButtons=callback in the binding from the article.

[hodatorabi]

Thank you, I will definitely try this.