Scala Scala Basics and Syntax 3

Question 1

What is the result of `List(1, 2, 3).head` in Scala?

Accepted Answer

1

Answer

The `head` method on a Scala List returns the first element, which is 1 in this case.

Question 2

Which Scala keyword is used to extend a class?

Accepted Answer

extends

Answer

Scala uses the `extends` keyword for class inheritance, allowing a subclass to inherit fields and methods from a parent class.

Question 3

What is the difference between `==` and `eq` in Scala?

Accepted Answer

== checks value equality; eq checks reference equality

Answer

In Scala, `==` performs structural (value) equality while `eq` checks reference identity (same object in memory).

Question 4

How do you create an Array of integers in Scala?

Accepted Answer

Array(1, 2, 3)

Answer

Scala provides the companion object syntax `Array(1, 2, 3)` to create an array using the `apply` factory method.

Question 5

What does `lazy val` do in Scala?

Accepted Answer

Defers evaluation of a value until first access

Answer

`lazy val` in Scala defers the computation of a value until the first time it is accessed, then caches the result.

Scala Practice Test