Kotlin 1.3.70
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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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Packages and Imports
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Functions
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Collections
Collections Overview
Constructing Collections
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Operations Overview
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Coroutines
Coroutines Guide
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Select Expression (experimental)
Multiplatform Programming
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Standard Library
kotlin.test
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Java Interop
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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 / HashSet / retainAll

retainAll

Common
1.0
fun retainAll(elements: Collection<E>): Boolean
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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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