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Kotlin Standard Library
The Kotlin Standard Library provides living essentials for everyday work with Kotlin. These include:
- Higher-order functions implementing idiomatic patterns (let, apply, use, synchronized, etc).
- Extension functions providing querying operations for collections (eager) and sequences (lazy).
- Various utilities for working with strings and char sequences.
- Extensions for JDK classes making it convenient to work with files, IO, and threading.
Packages
kotlin
Core functions and types, available on all supported platforms.
kotlin.annotation
Library support for the Kotlin annotation facility.
kotlin.browser
Access to top-level properties (document
, window
etc.) in the browser environment.
kotlin.collections
Collection types, such as Iterable, Collection, List, Set, Map and related top-level and extension functions.
kotlin.comparisons
Helper functions for creating Comparator instances.
kotlin.concurrent
Utility functions for concurrent programming.
kotlin.contracts
Experimental DSL for declaring custom function contracts.
kotlin.coroutines
Basic primitives for creating and suspending coroutines: Continuation, CoroutineContext interfaces, coroutine creation and suspension top-level functions.
kotlin.coroutines.cancellation
kotlin.coroutines.intrinsics
Low-level building blocks for libraries that provide coroutine-based APIs.
kotlin.dom
Utility functions for working with the browser DOM.
kotlin.enums
kotlin.experimental
Experimental APIs, subject to change in future versions of Kotlin.
kotlin.io
IO API for working with files and streams.
kotlin.io.encoding
kotlin.io.path
Convenient extensions for working with file system using java.nio.file.Path.
kotlin.js
Functions and other APIs specific to the JavaScript platform.
kotlin.jvm
Functions and annotations specific to the Java platform.
kotlin.jvm.optionals
Convenience extension functions for java.util.Optional
to simplify Kotlin-Java interop.
kotlin.math
Mathematical functions and constants.
kotlin.native
kotlin.native.concurrent
kotlin.native.ref
kotlin.native.runtime
kotlin.properties
Standard implementations of delegates for delegated properties and helper functions for implementing custom delegates.
kotlin.random
Provides the default generator of pseudo-random values, the repeatable generator, and a base class for other RNG implementations.
kotlin.ranges
Ranges, Progressions and related top-level and extension functions.
kotlin.reflect
Runtime API for Kotlin reflection
kotlin.reflect.full
Extensions for Kotlin reflection provided by kotlin-reflect
library.
kotlin.reflect.jvm
Runtime API for interoperability between Kotlin reflection and Java reflection provided by kotlin-reflect
library.
kotlin.sequences
Sequence type that represents lazily evaluated collections. Top-level functions for instantiating sequences and extension functions for sequences.
kotlin.streams
Utility functions for working with Java 8 streams.
kotlin.system
System-related utility functions.
kotlin.text
Functions for working with text and regular expressions.
kotlin.time
API for representing Duration values and experimental API for measuring time intervals.
kotlinx.browser
kotlinx.cinterop
kotlinx.cinterop.internal
kotlinx.dom
kotlinx.wasm.jsinterop
org.khronos.webgl
Kotlin JavaScript wrappers for the WebGL API.
org.w3c.css.masking
org.w3c.dom
Kotlin JavaScript wrappers for the DOM API.
org.w3c.dom.clipboard
org.w3c.dom.css
Kotlin JavaScript wrappers for the DOM CSS API.
org.w3c.dom.encryptedmedia
org.w3c.dom.events
Kotlin JavaScript wrappers for the DOM events API.
org.w3c.dom.mediacapture
org.w3c.dom.mediasource
org.w3c.dom.parsing
Kotlin JavaScript wrappers for the DOM parsing API.
org.w3c.dom.pointerevents
org.w3c.dom.svg
Kotlin JavaScript wrappers for the DOM SVG API.
org.w3c.dom.url
Kotlin JavaScript wrappers for the DOM URL API.
org.w3c.fetch
Kotlin JavaScript wrappers for the W3C fetch API.
org.w3c.files
Kotlin JavaScript wrappers for the W3C file API.
org.w3c.notifications
Kotlin JavaScript wrappers for the Web Notifications API.
org.w3c.performance
Kotlin JavaScript wrappers for the Navigation Timing API.
org.w3c.workers
Kotlin JavaScript wrappers for the Web Workers API.
org.w3c.xhr
Kotlin JavaScript wrappers for the XMLHttpRequest API.
Index
All Types© 2010–2023 JetBrains s.r.o. and Kotlin Programming Language contributors
Licensed under the Apache License, Version 2.0.
https://kotlinlang.org/api/latest/jvm/stdlib/index.html