Object-oriented programming · interview question
How would you explain an invariant in object design in an interview?
Multiple choiceHardchapter-3-curatedpremiumoopinvariants-and-validation
Answer and explanation
Correct answer
A. A rule that should always remain true for a valid object
Why
Invariants define what valid state means. Constructors and mutation methods should protect those rules so the object cannot drift into nonsense business data.
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