Language Upgrades · interview question

What happens if a new subclass is added to a sealed class hierarchy but is not handled in an existing pattern matching switch expression?

Multiple choiceMediumchapter-12-curatedpremiumlanguage-upgradespattern-matching

The code will not compile due to missing case handling.The code will compile with a warning but run without issue.The code will compile but might throw a runtime exception.The code will compile and automatically handle the new case.

Answer and explanation

Correct answer

A. The code will not compile due to missing case handling.

Why

In a pattern matching switch expression, if all subclasses of a sealed class are not handled, the code will fail to compile, ensuring all cases are considered.

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What happens if a new subclass is added to a sealed class hierarchy but is not handled in an existing pattern matching switch expression?

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