Code shared from the Rust Playground

playground.rs

fn main() {

    // Match is an expression as well as a statement. This example shows how
    // a variable is set based on an Option enum.
    // ------------------------------------------
    let msg_option = Some("+++MELON MELON MELON+++");   // Some variant
    let msg_option_empty = None;                        // None variant

    let msg = match msg_option {
        Some(m) => m,   // m is the unwrapped data from the option
        None => "Out of Cheese Error",
    };
    println!("msg = {}", msg);
    
    // As above, but handling the None variant
    let msg_2 = match msg_option_empty {
        Some(m) => m,   // In this case we won't enter this branch
        None => "Out of Cheese Error", // msg_2 set to this value
    };
    println!("msg_2 = {}", msg_2);
}

// Output:
// msg = +++MELON MELON MELON+++
// msg_2 = Out of Cheese Error