Variables and Immutability

Snippet

Variables and Immutability

In Rust, variables are immutable by default, meaning their value cannot change once bound. To allow a variable to be updated, you must explicitly use the 'mut' keyword.

snippet.rs
rust
fn main() {
    let x = 5;
    // x = 6; // This would cause a compile error
    let mut y = 10;
    y = 11; // This is allowed
    println!("x: {x}, y: {y}");
}

Breakdown

let x = 5;

Declares an immutable variable x with the value 5.

let mut y = 10;

Declares a mutable variable y, allowing its value to be changed later.

y = 11;

Reassigns a new value to the mutable variable y.

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