#!/usr/bin/ruby

#
## https://rosettacode.org/wiki/Menu
#

func menu (prompt, arr) {
    arr.len > 0 || return '';
    loop {
        arr.range.each { |i|
            say "  #{i}: #{arr[i]}";
        };
        var n = Sys.scanln(prompt);
        n ~~ /^[0-9]+\z/ ? n.to_i! : next;
        arr.exists(n) && return arr[n];
    }
}
 
var list = ['fee fie', 'huff and puff', 'mirror mirror', 'tick tock'];
var prompt = 'Please choose an item number: ';
 
var answer = menu(prompt, list);
say "You choose: #{answer}";