Variables and Mutability in Rust

Snippet

Variables and Mutability in Rust

In Rust, variables are immutable by default, which encourages writing safer code. To make a variable mutable, you must explicitly use the `mut` keyword. This design prevents accidental modifications and makes code behavior easier to reason about.

snippet.rs

rust

fn main() {
    let immutable = 42;
    println!("Immutable: {}", immutable);
 
    let mut mutable_var = 10;
    println!("Before mutation: {}", mutable_var);
 
    mutable_var = 15;
    println!("After mutation: {}", mutable_var);
 
}

Breakdown

let immutable = 42;

Creates an immutable variable. Its value cannot be changed after initialization.

let mut mutable_var = 10;

Creates a mutable variable with `mut`. The value can be reassigned later.

mutable_var = 15;

Successfully reassigns the mutable variable to a new value.

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Variables and Mutability in Rust

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