Hands-on practice for this lecture. Work through the exercises and quizzes to reinforce what you've learned.
Exercise 1 of 1
See how three boolean flags can reach impossible combinations, and how a discriminated union makes those combinations unrepresentable.
Current state
Click Lookup (Error), then immediately click Lookup (Success). Watch how isError stays true during the loading phase. Or click Force Impossible State — the type system cannot stop it.