https://github.com/benadamstyles/bs-fluture

Reason bindings for Fluture.js
https://github.com/benadamstyles/bs-fluture

Last synced: 4 days ago
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Reason bindings for Fluture.js

• Host: GitHub
• URL: https://github.com/benadamstyles/bs-fluture
• Owner: benadamstyles
• Created: 2018-11-27T15:21:44.000Z (about 6 years ago)
• Default Branch: master
• Last Pushed: 2023-04-04T00:00:03.000Z (over 1 year ago)
• Last Synced: 2024-12-03T15:46:28.363Z (20 days ago)
• Language: Reason
• Homepage: https://www.npmjs.com/package/bs-fluture
• Size: 1.74 MB
• Stars: 11
• Watchers: 2
• Forks: 2
• Open Issues: 8
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md

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README

        
# Fluture for ReScript / ReasonML / BuckleScript

[ReasonML](https://reasonml.github.io/) bindings for [Fluture](https://github.com/fluture-js/Fluture).

> **NOTE:** v1+ of `bs-fluture` is only compatible with v12+ of Fluture (see v12's [Breaking Changes document](https://gist.github.com/Avaq/ee2c6c819db4c37258e9a226e6380a38#functions-use-simple-currying) for more details).

> If you are using v11 of Fluture or lower, you must use v0.x of `bs-fluture`.

This library of bindings does not currently cover 100% of the Fluture API, although it does cover the vast majority of the commonly-used API, especially for the ReScript/ReasonML context. Please file an issue if one of the bindings is missing, wrong or it isn't working for you in general.

## Justification

Futures give the following benefits over Promises:

- Futures are lazy, rather than eager. Creating a future doesn't actually perform the async task – that only happens when you consume the future with e.g. `fork()`. Promises, on the other hand, perform their async task as soon as they are created. If you want a Promise that you can pass around without actually running it, you have to wrap it in a function, introducing more boilerplate.

- Cancellation is a built-in feature of futures.

- Unlike Promises (even in Reason!), Futures explicitly type their error states.

## Installation

```sh

npm install --save bs-fluture

```

Then add bs-fluture to bs-dependencies in your `bsconfig.json`:

```json

{

  "bs-dependencies": ["bs-fluture"]

}

```

## Usage

```reason

let future =

  Fluture.make((reject, resolve) => {

    let timeoutId =

      Js.Global.setTimeout(

        () =>

          if (Random.bool()) {

            resolve("success");

          } else {

            reject("error");

          },

        30,

      );

    /** EITHER return a wrapped cancellation function ... */

    Fluture.Cancel(() => Js.Global.clearTimeout(timeoutId));

    /** ... OR return NoCancel if there is no way to clean up. */

    Fluture.NoCancel;

  });

let cancelFuture =

  future

  |> Fluture.fork(error => Js.Console.error(error), response => Js.log(response));

/**

 * Due to runtime type-checking in Fluture,

 * the cancellation function must be explicitly uncurried.

 */

cancelFuture(.);

```

## let-anything

This package is compatible with [let-anything](https://github.com/jaredly/let-anything) – use it like this:

```reason

let getDefaultUsername = (futureEmail: Fluture.t(Js.Exn.t, string)) => {

  let%Fluture email = futureEmail;

  let name = Js.String.split(email, "@")[0];

  Fluture.resolve(name);

};

```