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Kotlin Cheat Sheet
Print-ready cheat sheet for Kotlin, organized for fast lookup, study, and desk-side use
Sample
What's in this cheat sheet
- Basics
- Functions
- Classes
- Null Safety
- Collections
- Coroutines
- Extensions
- Data Classes
- Sealed Classes
- Scope Functions
Hello World
fun main() {
println("Hello, World!")
}
Variables
val name = "Kotlin" // immutable (prefer)
var count = 0 // mutable
val pi: Double = 3.14159 // explicit type
const val MAX = 100 // compile-time constant
Basic Types
Int, Long | 32-bit / 64-bit signed integers |
Double, Float | 64-bit / 32-bit floating point |
Boolean | `true` / `false` |
Char | Single Unicode character |
String | Immutable text, supports templates |
Unit | Equivalent to `void` (single value) |
Nothing | Function never returns (e.g., throws) |
Download the full cheat sheet for all sections, formatted for print
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