Kotlin Kotlin Functional Programming

Question 1

What is a lambda expression in Kotlin?

Accepted Answer

An anonymous function literal that can be stored in a variable or passed as an argument

Answer

A lambda in Kotlin is an anonymous function literal enclosed in `{}` that can be passed as a value or stored in a variable.

Question 2

What does `it` refer to inside a Kotlin lambda?

Accepted Answer

The implicit single parameter of the lambda

Answer

When a lambda has exactly one parameter, Kotlin allows you to omit the parameter declaration and refer to it as `it`.

Question 3

What is a higher-order function in Kotlin?

Accepted Answer

A function that takes functions as parameters or returns a function

Answer

A higher-order function in Kotlin takes one or more functions as arguments or returns a function as its result.

Question 4

What is function composition in Kotlin?

Accepted Answer

Combining two functions into a new function where one's output is the other's input

Answer

Function composition creates a new function by chaining two functions so the output of the first becomes the input of the second.

Question 5

What does the `let` scope function do in Kotlin?

Accepted Answer

Calls a lambda with the object as its argument and returns the lambda result

Answer

`let` calls the lambda block with the receiver object as the argument (`it`) and returns the result of the lambda.

Kotlin Practice Test