Kotlin

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Overview

Kotlin for Server Side

Kotlin for Android

Kotlin for JavaScript

Kotlin for Native

What's New in 1.1

What's New in 1.2

What's New in 1.3

Getting Started

Coding Conventions

Basics

Packages and Imports

Returns and Jumps

Classes and Objects

Classes and Inheritance

Properties and Fields

Visibility Modifiers

Delegated Properties

Functions and Lambdas

Inline Functions

Collections

Collections Overview

Constructing Collections

Ranges and Progressions

Operations Overview

Transformations

Plus and Minus Operators

Retrieving Collection Parts

Retrieving Single Elements

Aggregate Operations

Collection Write Operations

List Specific Operations

Set Specific Operations

Map Specific Operations

Multiplatform Programming

Platform-Specific Declarations

Building with Gradle

Other

Destructuring Declarations

Type Checks and Casts

This expressions

Operator overloading

Scope Functions

Type-Safe Builders

Experimental API Markers

Core Libraries

Standard Library

Reference

Keywords and Operators

Java Interop

Calling Java from Kotlin

Calling Kotlin from Java

JavaScript

Calling JavaScript from Kotlin

Calling Kotlin from JavaScript

JavaScript Modules

JavaScript Reflection

Native

Kotlin Libraries

Platform Libraries

Objective-C and Swift Interop

CocoaPods Integration

Coroutines

Coroutines Guide

Cancellation and Timeouts

Composing Suspending Functions

Coroutine Context and Dispatchers

Exception Handling

Select Expression

Shared Mutable State and Concurrency

Tools

Documenting Kotlin Code

Kotlin and OSGi

Compiler plugins

Coding Conventions

Evolution

Kotlin Evolution

Stability of different components

Compatibility Guide for Kotlin 1.3

FAQ

Comparison to Java

kotlin-stdlib / kotlinx.cinterop / optional

optional

Native

1.3

fun optional(): Nothing

Licensed under the Apache 2 license

Kotlin Trademark is protected under the Kotlin Foundation

Press kit

Sponsored and developed by JetBrains

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