Language Upgrades · interview question
What must be true for a class to extend a sealed class and be marked as 'non-sealed'?
Multiple choiceMediumchapter-12-curatedpremiumlanguage-upgradessealed-classes
Answer and explanation
Correct answer
B. It must be listed in the permits clause of the sealed class.
Why
For a class to extend a sealed class and be marked as 'non-sealed', it must first be listed in the sealed class's 'permits' clause. This ensures that the sealed class hierarchy is adhered to, allowing controlled extensions.
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