Js.Promise-error-handling.re

Js.Promise-error-handling.re

exception SomeError;
exception JsError(Js.Exn.t);

let makeJsError: unit => Js.Promise.t(unit) = [%bs.raw
  {|() => Promise.reject(new Error("aaaa"))|}
];

let catch_ = (ocamlhandler, jshandler, promise) => {
  let a = e =>
    switch (ocamlhandler(e)) {
    | Some(x) => x
    | None => jshandler(e)
    };

  promise |> Js.Promise.catch(error => a(error));
};

Js.Promise.resolve()
/* |> Js.Promise.then_(() => Js.Promise.reject(SomeError)) */
|> Js.Promise.then_(() => makeJsError())
|> catch_(
     [@bs.open]
     (
       fun
       | SomeError => {
           Js.log("SomeError");
           Js.Promise.resolve();
         }
     ),
     [%bs.raw
       {|
        function(e) {
          console.log(">>>>>>>>>>", e);
        }
      |}
     ],
   );