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.");
}