QuestenaUn entraînement qui indique quoi revoir ensuite
RechercheCréer un test
Question 68

base.rank is 1, and item inherits from base without defining rank itself. What does Object.hasOwn(item, "rank") return?

  1. 1, because it returns the inherited value
  2. undefined, because it returns the missing own value
  3. true, because inherited properties count as owned
  4. false, because rank is not item's own propertyBonne réponse

Explication

Object.hasOwn examines only properties belonging directly to the supplied object, so an inherited rank does not qualify. A true result based on prototype lookup would describe the in operator instead.

Continuer avec ce test

Commencer l’entraînement
Comprendre ce thème (≈5 min)Retour au test
Question 68: base.rank is 1, and item inherits from base without… · JavaScript Fundamentals · Questena