Kotlin quiz

Test your Kotlin knowledge with a free interactive quiz — 50 questions with answers and explanations. No signup needed to play.

What is the difference between `==` and `===` in Kotlin?

1. What is the difference between `==` and `===` in Kotlin?
2. What does the Elvis operator `?:` do?
3. Why does this fail to compile: `var name: String = null`?
4. What does this return: `listOf(1, 2, 3).map { it * 2 }`?
5. What does the safe-call operator `?.` do?
6. Which loop iterates over a range of integers `1..10`?
7. What does `object MyService { … }` declare?
8. What is the difference between `List` and `MutableList`?
9. What does the `lazy` delegate do?
10. Are `String` template expressions evaluated at compile time?
11. What is the difference between `let` and `apply` scope functions?
12. What is the difference between `val` and `var` in Kotlin?

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