Null Safety · 5.1
Optional Types
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In Zolo, nil can only be assigned to optional types (T?):
let name: str? = "Alice"
let empty: str? = nil
// ?? provides a default value
let result = empty ?? "unknown"
print(result) // unknownGoal: Use ?? to print the user's name or "Anonymous" if it is nil.
lesson-5-1.zolo
Program output
Run the code to see the output