use std::collections::HashMap;

fn main() {
    let c: &'static str = "C";
    let mut map: HashMap<&'static str, Box<Fn()>> = HashMap::new();
    map.insert("A", Box::new(|| { println!("A") }));
    map.insert("B", Box::new(test));
    map.insert("C", Box::new(|| println!("{}", c)));

    map.get("A").unwrap()();
    map.get("B").unwrap()();
    map.get("C").unwrap()();
}

fn test() {
    println!("B");
}