use std::collections::BTreeMap;

#[derive(Debug)]
struct MenuItem<F: FnOnce()> {
    name: &'static str,
    description: &'static str,
    f: F,
}

fn main() {
    let mut main_menu = BTreeMap::new();
    // how to reference fn show_help() in line below??
    main_menu.insert(
        "h",
        MenuItem {
            name: "help",
            description: "Show help.",
            f: || { /* do things */ },
        },
    );
    main_menu.insert(
        "q",
        MenuItem {
            name: "quit",
            description: "Quit the program.",
            f: || {},
        },
    );

    //dbg!(main_menu);

    show_menu(main);
}

fn menu() {
    // show menu in a loop until a break condition is satisfied...
}

fn show_help() {
    println!("You appear to need help.");
}