bs-result

Monadic interface for Belt.Result

This implementation is inspired by JavaScript Fantasy Land and closely follows the Funfix.org Either implementation.

Installation

Install the bs-result package.
```
yarn add bs-result
```

Add bs-result to your bsconfig.json

{
  "dependencies": [
    "bs-result"
  ]
}

Usage

Basic

let r =
  Result.return(20)
  |> Result.map(x => x + 20)
  |> Result.flatMap(x => Result.return(x + 2))
  |> Result.getOrElse(-1);
Js.log2("Result: ", r);

[@@@ocaml.ppx.context { cookies = [] }]
let r =
  (((Result.return 20) |> (Result.map (fun x  -> x + 20))) |>
     (Result.flatMap (fun x  -> Result.return (x + 2))))
    |> (Result.getOrElse (-1))
let _ = Js.log2 (("Result: ")[@reason.raw_literal "Result: "]) r

Integrations

Belt.Result

let r =
  Belt.Result.Ok(x => x + 10)
  |> Result.ap(Result.return(20))
  |> Belt.Result.map(_, x => x + 10)
  |> Result.flatMap(x => Belt.Result.Ok(x + 2))
  |> Belt.Result.getWithDefault(_, -1);
Js.log2("Result: ", r);

[@@@ocaml.ppx.context { cookies = [] }]
let r =
  (((((Belt.Result.Ok ((fun x  -> x + 10)))[@explicit_arity ]) |>
       (Result.ap (Result.return 20)))
      |> (fun __x  -> Belt.Result.map __x (fun x  -> x + 10)))
     |>
     (Result.flatMap
        (fun x  -> ((Belt.Result.Ok ((x + 2)))[@explicit_arity ]))))
    |> (fun __x  -> Belt.Result.getWithDefault __x (-1))
let _ = Js.log2 (("Result: ")[@reason.raw_literal "Result: "]) r

Js.Promise

  Js.Promise.resolve(20)
  |> Js.Promise.then_(x => Result.Promise.return(x))
  |> Result.Promise.flatMap(x => Result.return(x + 10))
  |> Result.Promise.map(x => x + 10)
  |> Result.Promise.andThen(x =>
       x + 2 |> Result.return |> Js.Promise.resolve
     )
  |> Result.Promise.unsafeResolve
  |> Js.Promise.then_(result => {
       Js.log2("Result: ", result);
       Js.Promise.resolve();
     })

[@@@ocaml.ppx.context { cookies = [] }]
let _ =
  ((((((Js.Promise.resolve 20) |>
         (Js.Promise.then_ (fun x  -> Result.Promise.return x)))
        |> (Result.Promise.flatMap (fun x  -> Result.return (x + 10))))
       |> (Result.Promise.map (fun x  -> x + 10)))
      |>
      (Result.Promise.andThen
         (fun x  -> ((x + 2) |> Result.return) |> Js.Promise.resolve)))
     |> Result.Promise.unsafeResolve)
    |>
    (Js.Promise.then_
       (fun result  ->
          Js.log2 (("Result: ")[@reason.raw_literal "Result: "]) result;
          Js.Promise.resolve ()))

Full API Docs

TODO

[ ] Integration with reason-future.
[ ] Comonad implementation - functions are mis-named.