Rust for JavaScript Developers: Why You Should Learn Rust in 2025

rust
fn main() {
    let name = "World";
    println!("Hello, {}!", name);
}

rust
let x = 5;      // Immutable
// x = 6;       // ❌ Compile error!

let mut y = 5;  // Mutable
y = 6;          // ✅ Works

rust
fn main() {
    let s1 = String::from("hello");
    let s2 = s1;  // s1 is "moved" to s2
    
    // println!("{}", s1);  // ❌ Compile error! s1 is no longer valid
    println!("{}", s2);     // ✅ Works
}

javascript
let s1 = "hello";
let s2 = s1;  // Both s1 and s2 point to the same data
console.log(s1);  // ✅ Works (JavaScript copies references)

rust
fn calculate_length(s: &String) -> usize {
    s.len()
}  // s goes out of scope, but since it's a reference, nothing is dropped

fn main() {
    let s = String::from("hello");
    let len = calculate_length(&s);  // Borrow s
    println!("Length of '{}' is {}", s, len);  // ✅ s is still valid
}

rust
enum Shape {
    Circle(f64),
    Rectangle(f64, f64),
    Triangle(f64, f64, f64),
}

fn area(shape: &Shape) -> f64 {
    match shape {
        Shape::Circle(r) => std::f64::consts::PI * r * r,
        Shape::Rectangle(w, h) => w * h,
        Shape::Triangle(a, b, c) => {
            let s = (a + b + c) / 2.0;
            (s * (s-a) * (s-b) * (s-c)).sqrt()
        }
    }
}

rust
use std::fs;

fn read_file(path: &str) -> Result<String, std::io::Error> {
    fs::read_to_string(path)
}

fn main() {
    match read_file("data.txt") {
        Ok(content) => println!("File: {}", content),
        Err(e) => eprintln!("Error: {}", e),
    }
    
    // Or use the ? operator for concise error propagation
    let content = fs::read_to_string("data.txt")?;
}

bash
# Install Rust
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

# Create a new project
cargo new my-project
cd my-project
cargo run