import kotlin.test.*

fun main() { 
   //sampleStart 
   val empty = emptyList<Any>()
println("empty.isNotEmpty() is ${empty.isNotEmpty()}") // false

val collection = listOf('a', 'b', 'c')
println("collection.isNotEmpty() is ${collection.isNotEmpty()}") // true 
   //sampleEnd
}
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val empty = emptyList<Any>()
println("empty.isNotEmpty() is ${empty.isNotEmpty()}") // false
val collection = listOf('a', 'b', 'c')
println("collection.isNotEmpty() is ${collection.isNotEmpty()}") // true 
Open in Playground →
Target: JVMRunning on v.2.1.20

inline fun <K, V> Map<out K, V>.isNotEmpty(): Boolean(source)

Returns true if this map is not empty.

Since Kotlin

1.0

Samples

import kotlin.test.*
import java.util.*

fun main() { 
   //sampleStart 
   fun totalValue(statisticsMap: Map<String, Int>): String =
    when {
        statisticsMap.isNotEmpty() -> {
            val total = statisticsMap.values.sum()
            "Total: [$total]"
        }
        else -> "<No values>"
    }

val emptyStats: Map<String, Int> = mapOf()
println(totalValue(emptyStats)) // <No values>

val stats: Map<String, Int> = mapOf("Store #1" to 1247, "Store #2" to 540)
println(totalValue(stats)) // Total: [1787] 
   //sampleEnd
}
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fun totalValue(statisticsMap: Map<String, Int>): String =
    when {
        statisticsMap.isNotEmpty() -> {
            val total = statisticsMap.values.sum()
            "Total: [$total]"
        }
        else -> "<No values>"
    }
val emptyStats: Map<String, Int> = mapOf()
println(totalValue(emptyStats)) // <No values>
val stats: Map<String, Int> = mapOf("Store #1" to 1247, "Store #2" to 540)
println(totalValue(stats)) // Total: [1787] 
Open in Playground →
Target: JVMRunning on v.2.1.20

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