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Вопрос 15

A variable a refers to an array. Variable b is assigned a, with no new array created. What is a === b?

  1. false because arrays are mutable
  2. undefined because arrays lack equality
  3. true because both refer to one objectПравильный ответ
  4. true only when the array is empty

Объяснение

Both variables refer to the same array object, so strict equality produces true. Equal-looking but separately created arrays would fail this test because object strict equality depends on shared identity.

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Вопрос 15: A variable a refers to an array. Variable b is assigned a,… · JavaScript Fundamentals · Questena