Kotlin 1.3.70
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Overview
Kotlin for Server Side
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Coroutines
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What's New
What's New in 1.3
What's New in 1.2
What's New in 1.1
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Collections Overview
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Coroutines Guide
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Kotlin Evolution
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Compatibility Guide for Kotlin 1.3
FAQ
FAQ
Comparison to Java
kotlin-stdlib / kotlin.collections / HashMap / keys

keys

Common
Native
1.0
val keys: MutableSet<K>

Returns a MutableSet of all keys in this map.

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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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