Kotlin v1.4.21
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Overview
Kotlin for Server Side
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Coroutines
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What's New
Kotlin plugin 2020.3
Kotlin 1.4.20
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Kotlin Roadmap
Getting Started
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Functions and Lambdas
Functions
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Collections
Collections Overview
Constructing Collections
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Operations Overview
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Plus and Minus Operators
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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
Kotlin Multiplatform
Create a multiplatform library
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Publish a multiplatform library
Build final native binaries
Supported platforms
Multiplatform Gradle DSL Reference
Migrating to Kotlin 1.4
More Language Constructs
Destructuring Declarations
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This expressions
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Standard Library
kotlin.test
Reference
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Java Interop
Calling Java from Kotlin
Calling Kotlin from Java
JavaScript
Setting Up a Project
Dynamic Type
Calling JavaScript from Kotlin
Calling Kotlin from JavaScript
JavaScript Modules
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Generating External Declarations with Dukat
Native
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Evolution
Kotlin Evolution
Stability of Kotlin components
Compatibility Guide for Kotlin 1.3
Compatibility Guide for Kotlin 1.4
FAQ
FAQ
Comparison to Java
kotlin-stdlib / org.w3c.fetch / Headers / has

has

JS
1.1
fun has(name: String): Boolean
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Kotlin™ is protected under the Kotlin Foundation and licensed under the Apache 2 license. Supported and developed by JetBrains
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