Kotlin Typing Practice

Master Kotlin syntax with real-world code examples. Practice typing Kotlin code to boost your development speed and reduce syntax errors.

Start Kotlin Practice

Why Practice Kotlin Typing?

Null Safety

Master the ? and !! operators, plus the Elvis operator ?:.

Lambdas and Higher-Order Functions

Practice { } lambda syntax and the it keyword.

Data Classes and Sealed Classes

Get familiar with data class and sealed class declarations.

Extension Functions

Smoothly type syntax for adding functions to existing classes.

Common Kotlin Syntax

Practice these common Kotlin syntax patterns for smooth coding:

  • val name: String?
  • data class User(val id: Int)
  • list.filter { it > 0 }
  • fun String.extend()