WebAssembly (WASM) for High Performance Apps · Pelajaran

Interop JS yang Efisien dengan `wasm-bindgen`

Kuasai `wasm-bindgen` untuk bertukar struktur data kompleks dengan lancar dan berinteraksi antara WASM Rust dan JavaScript.

Interop JS yang Efisien dengan `wasm-bindgen` adalah pelajaran WebAssembly (WASM) for High Performance Apps gratis di CoddyKit. Ini adalah pelajaran 3 dari 4. Kamu bisa membaca pelajaran lengkapnya di bawah secara gratis — lalu praktikkan langsung di browser dengan editor kode bawaan dan tutor AI 24/7. Ini adalah bagian dari jalur belajar WebAssembly (WASM) for High Performance Apps, dan progresmu tersinkronisasi di web dan aplikasi CoddyKit. Kursus WebAssembly (WASM) for High Performance Apps mencakup 4 pelajaran total.

Bagian dari pelajaran ini belum diterjemahkan dan ditampilkan dalam bahasa Inggris.

Unlocking Complex Interop

Welcome to the final lesson on building high-performance WASM with Rust! So far, you've learned to set up Rust for WASM and write basic functions.

But what about exchanging complex data like strings, objects, or arrays? This is where wasm-bindgen comes in. It's a Rust tool that simplifies interaction between Rust and JavaScript.

What is `wasm-bindgen`?

wasm-bindgen is a utility that helps you create JavaScript bindings for Rust WebAssembly modules. It handles the low-level details of passing data types between the two languages.

Automates FFI: It automatically generates JavaScript glue code and Rust FFI (Foreign Function Interface) declarations.
Rich Type Support: It allows you to pass more complex types like String, JavaScript objects, and even DOM elements directly.
Improved Developer Experience: It makes your Rust WASM modules feel more like native JavaScript modules.

Setting Up for `wasm-bindgen`

To use wasm-bindgen, you need to add it as a dependency in your Cargo.toml. You'll also use the wasm-pack tool, which leverages wasm-bindgen to build your WASM module.

Add this to your Cargo.toml:

[dependencies]
wasm-bindgen = "0.2"

Then, mark your functions with #[wasm_bindgen].

Exporting Basic Functions

Let's start with a simple function. The #[wasm_bindgen] attribute makes a Rust function available to JavaScript.

Try running this example. The add_numbers function is exposed, and run_add_example demonstrates calling it.

use wasm_bindgen::prelude::*;

#[wasm_bindgen]
pub fn add_numbers(a: u32, b: u32) -> u32 {
    a + b
}

// This function serves as a runnable entry point for demonstration.
#[wasm_bindgen]
pub fn run_add_example() -> u32 {
    add_numbers(10, 5)
}

Passing Strings to Rust

One of wasm-bindgen's great features is how it handles strings. You can pass a JavaScript string directly to a Rust function expecting &str or String.

Here, the greet function takes a string argument from JavaScript.

use wasm_bindgen::prelude::*;

#[wasm_bindgen]
pub fn greet(name: &str) -> String {
    format!("Hello, {}!", name)
}

#[wasm_bindgen]
pub fn run_greet_example() -> String {
    greet("CoddyKit User")
}

Returning Strings from Rust

Similarly, Rust functions returning a String will automatically be converted into a JavaScript string. This makes working with text across the boundary very natural.

The get_message function returns a Rust String.

use wasm_bindgen::prelude::*;

#[wasm_bindgen]
pub fn get_message() -> String {
    String::from("This message came from Rust!")
}

#[wasm_bindgen]
pub fn run_get_message_example() -> String {
    get_message()
}

Exporting Structs as JS Classes

wasm-bindgen can also expose Rust structs as JavaScript classes. This allows you to create and manipulate Rust objects directly from JavaScript.

The User struct below becomes a class in JavaScript, complete with a constructor.

use wasm_bindgen::prelude::*;

#[wasm_bindgen]
pub struct User {
    name: String,
    age: u8,
}

#[wasm_bindgen]
impl User {
    #[wasm_bindgen(constructor)]
    pub fn new(name: String, age: u8) -> User {
        User { name, age }
    }
}

#[wasm_bindgen]
pub fn create_user_example() -> User {
    User::new("Alice".to_string(), 30)
}

Adding Methods to JS Classes

Once a Rust struct is exposed as a JavaScript class, you can add methods to its impl block. These methods will be callable directly on the JavaScript object.

Let's add a greet method to our User struct.

use wasm_bindgen::prelude::*;

#[wasm_bindgen]
pub struct User {
    name: String,
    age: u8,
}

#[wasm_bindgen]
impl User {
    #[wasm_bindgen(constructor)]
    pub fn new(name: String, age: u8) -> User {
        User { name, age }
    }

    pub fn greet(&self) -> String {
        format!("Hi, my name is {} and I'm {} years old.", self.name, self.age)
    }
}

#[wasm_bindgen]
pub fn run_user_greet_example() -> String {
    let user = User::new("Bob".to_string(), 25);
    user.greet()
}

Passing Rust Vectors to JS

wasm-bindgen can also handle basic collection types like Vec for primitive types. It will convert a Rust Vec into a JavaScript array.

This allows you to pass lists of numbers or strings easily.

use wasm_bindgen::prelude::*;

#[wasm_bindgen]
pub fn process_numbers(numbers: Vec<u32>) -> Vec<u32> {
    numbers.iter().map(|n| n * 2).collect()
}

#[wasm_bindgen]
pub fn run_process_numbers_example() -> Vec<u32> {
    let input = vec![1, 2, 3];
    process_numbers(input)
}

`wasm-bindgen` Interop Check

Which of the following statements about wasm-bindgen are TRUE?

Recap: Mastering Interop

You've now mastered wasm-bindgen, a powerful tool for seamless interaction between Rust and JavaScript in your WebAssembly projects.

It automates binding generation, making your Rust functions and types easily accessible from JS.
It enables the exchange of complex data types like strings, structs (as JS classes), and vectors.
This significantly improves developer experience, letting you write high-performance Rust logic that feels native in a JavaScript environment.

With wasm-bindgen, your Rust WASM modules can become integral, high-performance components of any web application!

Pertanyaan yang Sering Diajukan

Apakah pelajaran “Interop JS yang Efisien dengan `wasm-bindgen`” gratis?

Ya — teks lengkap “Interop JS yang Efisien dengan `wasm-bindgen`” gratis dibaca di sini di web. Untuk praktiknya secara interaktif (editor kode bawaan dan tutor AI 24/7) dan buka sisa kursus WebAssembly (WASM) for High Performance Apps, upgrade ke CoddyKit PRO. Kursus WebAssembly (WASM) for High Performance Apps mencakup 4 pelajaran total.

Apa yang akan aku pelajari di “Interop JS yang Efisien dengan `wasm-bindgen`”?

Kuasai `wasm-bindgen` untuk bertukar struktur data kompleks dengan lancar dan berinteraksi antara WASM Rust dan JavaScript. Kamu berlatih WebAssembly (WASM) for High Performance Apps dengan kode praktik yang langsung kamu jalankan di browser, dan tutor AI 24/7 menjawab pertanyaanmu saat kamu mengerjakan pelajaran ini.

Apakah aku perlu pengalaman untuk memulai WebAssembly (WASM) for High Performance Apps?

Tidak diperlukan pengalaman sebelumnya. WebAssembly (WASM) for High Performance Apps di CoddyKit dirancang untuk pemula hingga pelajar tingkat lanjut, jadi kamu bisa memulai di sini atau dari awal dan belajar sesuai kecepatan kamu sendiri. Ini adalah pelajaran 3 dari 4.

Berapa lama pelajaran “Interop JS yang Efisien dengan `wasm-bindgen`” memakan waktu?

Sebagian besar pelajaran CoddyKit memakan waktu sekitar 5–10 menit. Setiap pelajaran ringkas dan interaktif, jadi kamu membuat kemajuan stabil dan melanjutkan dari tempat kamu tinggalkan di web dan aplikasi.

Bisakah aku menulis dan menjalankan kode dalam pelajaran WebAssembly (WASM) for High Performance Apps ini?

Ya. Setiap pelajaran WebAssembly (WASM) for High Performance Apps menyertakan editor kode bawaan, jadi kamu menulis dan menjalankan kode nyata langsung di browser dan mendapatkan umpan balik AI instan — tidak diperlukan penyiapan lokal.

Semua pelajaran dalam kursus ini

Menyiapkan Rust untuk WebAssembly
Menulis Fungsi Rust untuk WASM
Interop JS yang Efisien dengan `wasm-bindgen`
Penanganan Kesalahan di Seluruh Batas WASM

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