Kotlin Kotlin Functions and Lambdas

Question 1

What is a higher-order function in Kotlin?

Accepted Answer

A function that takes or returns another function

Answer

A higher-order function is one that accepts functions as parameters or returns a function as its result.

Question 2

What does the `it` keyword represent inside a Kotlin lambda?

Accepted Answer

The implicit single parameter of the lambda

Answer

When a lambda has exactly one parameter, Kotlin allows omitting the parameter declaration and referring to it as `it`.

Question 3

Which Kotlin keyword is used to mark a function as inline?

Accepted Answer

inline

Answer

The `inline` modifier tells the Kotlin compiler to substitute the function body at the call site, reducing lambda overhead.

Question 4

What is a lambda expression in Kotlin?

Accepted Answer

An anonymous function defined with curly braces

Answer

A lambda in Kotlin is an anonymous function literal enclosed in curly braces, which can be passed as a value.

Question 5

How do you pass a trailing lambda in Kotlin?

Accepted Answer

Place it outside the parentheses after the function call

Answer

Kotlin allows moving the last lambda argument outside the parentheses, a convention called trailing lambda syntax.

Kotlin Practice Test