rescript-bun

Use Bun with ReScript.

Getting started

Template repo to get up and running quickly: https://github.com/zth/rescript-bun-starter

You need to be on ReScript v12 >=12.0.0-alpha.4.

Install rescript-bun:

``bash
npm i rescript-bun@2
`

Include them in your rescript.json:

`json
{
"dependencies": ["rescript-bun"]
}
`

rescript-bun is namespaced, so you'll find all modules listed under the main module RescriptBun.

You're strongly encouraged to open RescriptBun globally, to get the best possible developer experience. You do that by adding this to your rescript.json:

`json
{
"bsc-flags": ["-open RescriptBun", "-open RescriptBun.Globals"]
}
`

> Notice -open RescriptBun.Globals. This will expose all Bun _globals_. This might be a matter of taste, but I recommend opening it to get the best experience.

This will make all of Bun available to you without needing to dip into the RescriptBun module explicitly.

Credits

This lib copies rescript-nodejs for Bun's Node compatible bindings. Shout out to the maintainers of that project!

Examples

Here's a few examples of how it looks. More examples (often inspired by https://bun.sh/guides) can be found in the playground/examples directory in this repo.

$3

To write tests using Bun's built in test runner, just open Test and you'll have everything available to you to write your tests:

`rescript
open Test

describe("Playing around with tests", () => {
test("addition works", () => {
expect(1 + 1)->Expect.toBe(2)
})
})
`

This will make all of Bun's testing utilities available to you in the global scope.

$3

Here's setting up a simple web server.

`rescript
let server = Bun.serve({
fetch: async (request, _server) => {
let userName =
request
->Request.headers
->Headers.get("x-user-name")
->Option.getOr("Unknown user")

Response.make(Hello ${userName}!, ~options={status: 200})
},
})

let port =
server
->Bun.Server.port
->Int.toString

let hostName = server->Bun.Server.hostname

Console.log(Server listening on http://${hostName}:${port}!)
`

$3

`rescript
let password = "super-secure-pa$$word"

let bcryptHash = await Bun.Password.hash(
password,
~algorithm=BCryptAlgorithm({
cost: 4, // number between 4-31
}),
)

let isMatch = await Bun.Password.verify(password, ~hash)
`

$3

`rescript
let router = Bun.FileSystemRouter.make({
style: NextJs,
dir: "./pages",
origin: "https://mydomain.com",
assetPrefix: "_next/static/",
})

let matches = router->Bun.FileSystemRouter.match("/")
`

$3

`rescript
// Rewrite all