sealed class
Also written: sealed
A class whose subclasses are all known when the code is compiled. Each value is exactly one of that fixed set of kinds, such as a Card, Cash or GiftCard payment, so `when` can be checked for completeness.
Also written: sealed
A class whose subclasses are all known when the code is compiled. Each value is exactly one of that fixed set of kinds, such as a Card, Cash or GiftCard payment, so `when` can be checked for completeness.