orEmpty

Common
JVM
Native
1.0
fun < reified T > Array < out T > ? . orEmpty ( ) : Array < out T >
(Common source) (JVM source) (Native source)
JS
1.1
fun < T > Array < out T > ? . orEmpty ( ) : Array < out T >
(source)

Returns the array if it's not null , or an empty array otherwise.

import kotlin.test.*

fun main(args: Array<String>) {
//sampleStart
val nullArray: Array<Any>? = null
println(nullArray.orEmpty().contentToString()) // []

val array: Array<Char>? = arrayOf('a', 'b', 'c')
println(array.orEmpty().contentToString()) // [a, b, c]
//sampleEnd
}
Common
JVM
JS
Native
1.0
fun < T > Collection < T > ? . orEmpty ( ) : Collection < T >
(source)

Returns this Collection if it's not null and the empty list otherwise.

import kotlin.test.*

fun main(args: Array<String>) {
//sampleStart
val nullCollection: Collection<Any>? = null
println(nullCollection.orEmpty()) // []

val collection: Collection<Char>? = listOf('a', 'b', 'c')
println(collection.orEmpty()) // [a, b, c]
//sampleEnd
}
Common
JVM
JS
Native
1.0
fun < T > List < T > ? . orEmpty ( ) : List < T >
(source)

Returns this List if it's not null and the empty list otherwise.

import kotlin.test.*

fun main(args: Array<String>) {
//sampleStart
val nullList: List<Any>? = null
println(nullList.orEmpty()) // []

val list: List<Char>? = listOf('a', 'b', 'c')
println(list.orEmpty()) // [a, b, c]
//sampleEnd
}
Common
JVM
JS
Native
1.0
fun < K , V > Map < K , V > ? . orEmpty ( ) : Map < K , V >
(source)

Returns the Map if its not null , or the empty Map otherwise.

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

fun main(args: Array<String>) {
//sampleStart
val nullMap: Map<String, Any>? = null
println(nullMap.orEmpty()) // {}

val map: Map<Char, Int>? = mapOf('a' to 1, 'b' to 2, 'c' to 3)
println(map.orEmpty()) // {a=1, b=2, c=3}
//sampleEnd
}
Common
JVM
JS
Native
1.0
fun < T > Set < T > ? . orEmpty ( ) : Set < T >
(source)

Returns this Set if it's not null and the empty set otherwise.