Innovative Kotlin Test - 78+ MCQs: Kotlin test: Evaluate Your Programming Skills with Kotlin Questions and Answers

1. How do you declare an array in Kotlin?

val myArray = array()

array myArray[]

val myArray = Array()

val myArray = arrayOf()

2. How do you declare an infix function in Kotlin?

fun infix myFunction() {}

fun myFunction() infix {}

infix fun myFunction() {}

myFunction() infix fun {}

3. In Kotlin, what is the 'elvis operator' used for?

To concatenate strings

To handle null values

To create conditional expressions

To define class inheritance

4. What is the purpose of the 'first' function in Kotlin?

To specify the first element of a collection

To apply a function to the first element of a collection

To retrieve the first element that matches a predicate

To create a new collection with the first element

5. In Kotlin, how do you create a secondary constructor?

constructor secondary() {}

class Secondary { constructor() }

class MyClass { secondary constructor() {} }

fun secondary() MyClass {}

6. What is the purpose of the 'sealed class' in Kotlin?

To restrict the inheritance of a class hierarchy

To declare a class with restricted access modifiers

To define a class with a limited number of instances

To create a class with private constructors

7. How do you define a class with a private constructor in Kotlin?

class MyClass { private constructor() }

class MyClass(private constructor()) {}

class MyClass private constructor() {}

class MyClass(private constructor) {}

8. What is the purpose of the 'reduce' function in Kotlin?

To reduce the size of a collection

To combine elements of a collection into a single result

To apply a function to each element of a collection

To remove null values from a collection

9. How do you declare a top-level function in Kotlin?

function myFunction() {}

fun myFunction() {}

top fun myFunction() {}

fun: myFunction() {}

10. How do you define a function in Kotlin?

function myFunction() {}

fun myFunction() {}

define myFunction() {}

fun: myFunction() {}

11. In Kotlin, what is the 'getter' keyword used for?

To specify the visibility modifier

To define the getter function for a property

To declare external declarations for platform-specific code

To create a lazy property

12. In Kotlin, what is the purpose of the 'let' extension function?

To create an extension function for nullable types

To handle program initialization

To apply a function to the result of a nullable expression

To define a lambda expression

13. How do you declare a nullable variable in Kotlin?

var x: Int = null

var x: Int? = null

val x: Int? = 0

val x: Int = null

14. In Kotlin, what is the purpose of the 'sequence' function?

To define a sequence of elements

To create an iterable collection

To handle program initialization

To apply a function to each element of a collection

15. What is the purpose of the 'noinline' modifier in Kotlin?

To prevent inlining of a function

To mark a function as non-nullable

To enforce immutability for a variable

To specify the return type of a function

16. What is the purpose of the 'by lazy' keyword in Kotlin?

To specify lazy loading for classes

To create a lazy property that is computed the first time it is accessed

To declare external declarations for platform-specific code

To define the priority of operators

17. How do you declare a package in Kotlin?

package com.example.myPackage

com.example.myPackage

declare package com.example.myPackage

package: com.example.myPackage

18. In Kotlin, what is the purpose of the 'step' parameter in a range?

To define the range size

To specify the range increment

To determine the range start

To calculate the range average

19. In Kotlin, what is the purpose of the 'by lazy' delegate?

To create a lazy-loaded variable

To delegate property initialization to another class

To implement lazy loading for functions

To define a variable with delayed initialization

20. How do you declare an enum class in Kotlin?

enum class MyEnum {}

class enum MyEnum {}

enum MyEnum : class {}

class MyEnum : enum {}

21. How does Kotlin handle null safety?

By allowing null values for all variables

By using the 'nullable' keyword

By introducing the 'null' type

By making nullable and non-nullable types explicit

22. What is the purpose of the 'forEach' function in Kotlin?

To iterate over a range of values

To perform a case-insensitive comparison

To iterate over elements of a collection

To apply a function to each element of a collection

23. In Kotlin, what is the 'operator overloading' feature used for?

To overload the '+' operator for custom classes

To define the priority of operators

To mark a class as an operator

To handle program initialization

24. In Kotlin, what is the 'typealias' keyword used for?

To define a type alias for a class

To specify the data type of a variable

To create a shortcut for a longer type

To declare a type with aliasing behavior

25. What is the default visibility modifier in Kotlin?

private

protected

internal

public

26. How do you declare a function with an infix notation in Kotlin?

fun add(a: Int, b: Int) = a infixPlus b

fun add(a: Int, b: Int) = a + infix b

infix fun add(a: Int, b: Int) = a + b

fun infix add(a: Int, b: Int) = a + b

27. What is the purpose of the 'expect' keyword in Kotlin?

To define expected behavior for a function

To specify the return type of a function

To declare external declarations for platform-specific code

To create conditional expressions

28. In Kotlin, what is the purpose of the 'inline' modifier for functions?

To specify that a function should be inlined during compilation

To declare a function as internal

To define a function with default parameters

To enforce immutability for a function

29. What is a primary constructor in Kotlin?

The main constructor of a class declared in the class header

A constructor that initializes primary data types

A constructor used for creating secondary instances

A constructor that initializes only nullable variables

30. What is the purpose of the 'apply' function in Kotlin?

To apply mathematical operations

To apply functions to each element of a collection

To configure the properties of an object during its creation

To handle program initialization

31. How do you declare a constant property in a class in Kotlin?

const val myProperty = 10

val constant myProperty = 10

property val myProperty = 10

val myProperty: Constant = 10

32. What is the purpose of the 'by' keyword in Kotlin?

To indicate the inheritance hierarchy

To specify the visibility modifier

To delegate property behavior to another object

To create a bi-directional reference

33. What is the purpose of the 'crossinline' modifier in Kotlin?

To declare external declarations for platform-specific code

To create a cross-platform function

To mark a function as non-nullable

To prevent non-local returns in an inline function

34. What is the purpose of the 'sealed' modifier in Kotlin?

To indicate that a class can be inherited

To restrict the inheritance of a class to its subclasses within the same file

To declare a class as abstract

To create a sealed package

35. In Kotlin, what is the 'invoke' operator used for?

To create an instance of a class

To define the behavior of calling an instance as a function

To specify the return type of a function

To declare external declarations for platform-specific code

36. What is the purpose of the 'operator' keyword in Kotlin?

To define mathematical operations for a class

To declare the priority of operators

To mark a class as an operator

To create conditional expressions

37. What is the purpose of the 'if' expression in Kotlin?

To create loops

To define conditional statements

To handle exceptions

To declare variables

38. In Kotlin, what is the purpose of the 'reified' keyword?

To declare a variable as reified

To create a recursive function

To specify a function as reified

Kotlin does not have a 'reified' keyword

39. What is the syntax for a multiline string in Kotlin?

`This is a multiline string`

'This is a multiline string'

"This is a multiline string"

'''This is a multiline string'''

40. Which collection type is immutable in Kotlin?

List

MutableList

Array

Set

41. What is the 'when' expression used for in Kotlin?

To define switch-case statements

To create conditional expressions

To handle exceptions

To iterate over collections

42. What is the 'by' keyword used for in Kotlin?

To declare a new variable

To indicate that a class can be delegated to another class

To define the inheritance hierarchy

To create a binary operation

43. What is the purpose of the 'let' extension function in Kotlin?

To create a new variable

To apply a function to each element of a collection

To define a scope for the current object

To handle program initialization

44. How does Kotlin handle extension properties?

Kotlin does not support extension properties

By using the 'extension' keyword

By declaring them in a separate extension file

By using the 'property' keyword

45. Which keyword is used to define a constant in Kotlin?

const

val

var

final

46. What is the purpose of the 'when' statement in Kotlin?

To create switch-case statements

To define loops

To handle exceptions

To create conditional expressions

47. In Kotlin, what is the purpose of the 'init' block?

To initialize global variables

To execute code before program execution begins

To handle program termination

To initialize properties of a class

48. What is the purpose of the 'trim' function in Kotlin?

To trim leading and trailing whitespace

To resize a collection

To remove null values from a collection

To handle program termination

49. In Kotlin, how do you create a class with a primary constructor?

class MyClass { constructor() }

class MyClass : constructor() {}

class MyClass constructor() {}

class MyClass() {}

50. Which keyword is used for type casting in Kotlin?

cast

convert

Kotlin MCQ Test 1