函式呼叫中的移動

將值傳遞至函式時，該值會指派給函式參數。這麼做會轉移所有權：

fn say_hello(name: String) {
    println!("Hello {name}")
}

fn main() {
    let name = String::from("Alice");
    say_hello(name);
    // say_hello(name);
}