Can i use it in reasonml?

[useada]

I use it in reasonml, compile with esy/dune, but got some error like this:

`
This is a syntax error.

Note: the location indicated might not be accurate.

error: command failed: 'refmterr' 'dune' 'build' '-p' 'hello-reason'
esy-build-package: exiting with errors above...
error: build failed
building [email protected]
esy: exiting due to errors above
`

my dune file likes this:

(preprocess (pps lwt_ppx ppx_deriving_yojson)) (libraries yojson core ppx_deriving_yojson.runtime)

What am I doing wrong?

[rizo]

You haven't shown the most important part – the syntax error in your source code.

In any case, I created a simple esy+dune project with ppx_deriving_yojson.

package.json:

{
  "name": "issue-89",
  "version": "0.0.0",
  "description": "Yojson ppx",
  "license": "MIT",
  "esy": {
    "build": "refmterr dune build"
  },
  "dependencies": {
    "refmterr": "*",
    "@opam/dune": "*",
    "ocaml": "4.6.x",
    "@esy-ocaml/reason": "*",
    "@opam/ppx_deriving_yojson": "*"
  }
}

---

dune:

(executable
  (public_name Main)
  (preprocess (pps ppx_deriving_yojson))
  (libraries yojson))

---

Main.re:

[@deriving yojson]
type person = {
  name: string,
  age: int
};

let json = person_to_yojson({ name: "Karel", age: 30 });
print_endline(Yojson.Safe.to_string(json));

---

With this you should be able to run esy install; esy build; esy x Main.

Hope this helps.

[roddycx]

What about using BuckleScript? I think that just needs an executable but I'm not sure where to get that.

[roddyyaga]

Update: yes you can use it in BuckleScript; see my fork here.