#[derive(Debug)] // 💡 A lint attribute which use to implement `std::fmt::Debug` to Color
struct Color {
    r: u8,
    g: u8,
    b: u8,
}

#[allow(unreachable_code)] // 💡 A lint attribute used to suppress the warning; unreachable statement
fn main() {
    let some_color: Color;

    // some code to get the color. ex
    some_color = Color {r: 255, g: 255, b: 0};

    // if we need to debug in here
    panic!("{:?}", some_color);

    println!(
        "The color = rgb({},{},{})",
        some_color.r, some_color.g, some_color.b
    );
}

// -------------- Compile time error --------------
thread 'main' panicked at 'Color { r: 255, g: 255, b: 0 }', src/main.rs:16:5