Example

Import JavaScript things into Rust and export Rust things to JavaScript.

use wasm_bindgen::prelude::*;

// Import the `window.alert` function from the Web.
#[wasm_bindgen]
extern "C" {
    fn alert(s: &str);
}

// Export a `greet` function from Rust to JavaScript, that alerts a
// hello message.
#[wasm_bindgen]
pub fn greet(name: &str) {
    alert(&format!("Hello, {}!", name));
}

Use exported Rust things from JavaScript with ECMAScript modules!

import { greet } from "./hello_world";

greet("World!");

Features

• Lightweight. Only pay for what you use. wasm-bindgen only generates
  bindings and glue for the JavaScript imports you actually use and Rust
  functionality that you export. For example, importing and using the
  document.querySelector method doesn't cause Node.prototype.appendChild or
  window.alert to be included in the bindings as well.

• ECMAScript modules. Just import WebAssembly modules the same way you would
  import JavaScript modules. Future compatible with WebAssembly modules and
  ECMAScript modules integration.

• Designed with the "Web IDL bindings" proposal in mind.
  Eventually, there won't be any JavaScript shims between Rust-generated wasm
  functions and native DOM methods. Because the wasm functions are statically
  type checked, some of those native methods' dynamic type checks should become
  unnecessary, promising to unlock even-faster-than-JavaScript DOM access.

Guide

📚 Read the wasm-bindgen guide here! 📚

You can find general documentation about using Rust and WebAssembly together
here.

API Docs

• wasm-bindgen
• js-sys
• web-sys
• wasm-bindgen-futures

License

This project is licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or
  http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or
  http://opensource.org/licenses/MIT)

at your option.

Contribution

See the "Contributing" section of the guide for information on
hacking on wasm-bindgen!

Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in this project by you, as defined in the Apache-2.0 license,
shall be dual licensed as above, without any additional terms or conditions.