let explore_caves = || { let secret_caves_found = vec::new(); while !secret_caves_found.contains(&"top_secret_cave") { secret_caves_found.push(explore_next_cave()); if secret_caves_found.last().unwrap() == &"top_secret_cave" { println!("congratulations! you've discovered the top secret cave. please omit this location in your preadmission questionnaires to keep it a secret. ready to commence once more on a new adventure?"); } } };