}
pub fn run(cfg: Config) -> Result<(), &'static str> {
    Ok(())

use std::io;

fn main() {

fn main() -> Result<(), &'static str> {

    let cfg_str = match env::var("TN_CONFIG") {

    let config_str = match env::var("TN_CONFIG") {

    if let Ok(cfg) = tn::read_config(&cfg_str) {

    // XXX: what's the general lifetime/scope of 'if let created variables'???
    if let Ok(config) = tn::read_config(&config_str) {

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

        println!("{:?}", config);
        // okay to take ownership
        tn::run(config)

        println!("not working properly");

        Err("no config file")