Chapter 1, Getting Started with Kotlin

Question 1

What's the difference between var and val in Kotlin?


The val keyword declares an immutable value that cannot be modified once assigned. The var keyword declares a mutable variable that can be assigned multiple times.

Question 2

How do you extend a class in Kotlin?


To extend a class, you can specify its name and constructor after a semicolon. If it's a regular class, it must be declared open for your code to be able to extend it.

Question 3

How do you add functionality to a final class?


To add functionality to a class that we cannot inherit from, we can use an extension function. The extension function will have access only to the class itself and to its public ...

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