Kotlin 1.3.72
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Overview
Kotlin for Server Side
Kotlin for Android
Kotlin for JavaScript
Kotlin for Native
Kotlin for Data Science
Coroutines
Multiplatform
What's New
What's New in 1.3
What's New in 1.2
What's New in 1.1
Getting Started
Basic Syntax
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Coding Conventions
Basics
Basic Types
Packages and Imports
Control Flow
Returns and Jumps
Classes and Objects
Classes and Inheritance
Properties and Fields
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Functions and Lambdas
Functions
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Collections
Collections Overview
Constructing Collections
Iterators
Ranges and Progressions
Sequences
Operations Overview
Transformations
Filtering
Plus and Minus Operators
Grouping
Retrieving Collection Parts
Retrieving Single Elements
Ordering
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Collection Write Operations
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Map Specific Operations
Coroutines
Coroutines Guide
Basics
Cancellation and Timeouts
Composing Suspending Functions
Coroutine Context and Dispatchers
Asynchronous Flow
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Exception Handling and Supervision
Shared Mutable State and Concurrency
Select Expression (experimental)
Multiplatform Programming
Platform-Specific Declarations
Building with Gradle
Multiplatform Gradle DSL Reference
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Destructuring Declarations
Type Checks and Casts
This expressions
Equality
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Scope Functions
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Opt-in Requirements
Core Libraries
Standard Library
kotlin.test
Reference
Keywords and operators
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Java Interop
Calling Java from Kotlin
Calling Kotlin from Java
JavaScript
Setting Up a Project
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Calling JavaScript from Kotlin
Calling Kotlin from JavaScript
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Evolution
Kotlin Evolution
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Compatibility Guide for Kotlin 1.3
FAQ
FAQ
Comparison to Java
kotlin-stdlib / kotlin.collections / Collection / size

size

Common
JVM
JS
Native
1.0
abstract val size: Int

Returns the size of the collection.

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Licensed under the Apache 2 license
Kotlin Trademark is protected under the Kotlin Foundation
Sponsored and developed by JetBrains
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