Variable shadowing

• let

• We can declare the same variable multiple time using the let keyword.

• The 2nd and subsequent declarations hide (shadow) the previous ones.

• If this happened inside a block then when the shadowing version of the variable goes out of scope the previous value becomes visible again. (Observe, the last line being 6.)

fn main() {
    let x = 5;
    println!("x={x}");

    let x = x + 1;
    println!("x={x}");

    {
        println!("x={x}");
        let x = x * 2;
        println!("x={x}");
    }

    println!("x={x}");
}

x=5
x=6
x=6
x=12
x=6