use std::io;

    let cfg = read_config("/home/frank/.tn").expect("could not generate config");

    if let Ok(cfg) = read_config("/home/frank/.tn") {
        println!("WORKING");
        println!("{:?}", cfg);
    } else {
        println!("not working properly");
    }

    println!("{:?}", cfg);

    // other variant would be with functional programming using closures and unwrap_or_else

fn read_config(cfgfile: &str) -> Result<Config, &'static str> {

fn read_config(cfgfile: &str) -> Result<Config, io::Error> {
    // XXX: read config and potentially retrun io::Error