Null Safety · 5.4
guard
All lessons are open — jump whenever you need.
guard checks a condition and exits the function if it fails:
fn process(name: str?) -> str {
guard name != nil else {
return "Name required"
}
let present_name = name ?? ""
return "Hello, {present_name}!"
}Goal: Implement validate_age that returns "Adult" or "Minor" using guard.
lesson-5-4.zolo
Program output
Run the code to see the output