kotlin-stdlib / kotlin.collections / listOf

listOf

Common

JVM

Native

1.0

fun <T> listOf(vararg elements: T): List<T>

Returns a new read-only list of given elements. The returned list is serializable (JVM).

import kotlin.test.*

fun main(args: Array<String>) {
//sampleStart
val list = listOf('a', 'b', 'c')
println(list.size) // 3
println("list.contains('a') is ${list.contains('a')}") // true
println(list.indexOf('b')) // 1
println(list[2]) // c
//sampleEnd
}

Common

JVM

Native

1.0

fun <T> listOf(): List<T>

Returns an empty read-only list. The returned list is serializable (JVM).

import kotlin.test.*

fun main(args: Array<String>) {
//sampleStart
val list = listOf<String>()
println("list.isEmpty() is ${list.isEmpty()}") // true

// another way to create an empty list,
// type parameter is inferred from the expected type
val other: List<Int> = emptyList()

// Empty lists are equal

println("list == other is ${list == other}") // true
println(list) // []
// list[0] //  will fail
//sampleEnd
}

JVM

1.0

fun <T> listOf(element: T): List<T>

For JVM

Returns an immutable list containing only the specified object element. The returned list is serializable.

import kotlin.test.*

fun main(args: Array<String>) {
//sampleStart
val list = listOf('a')
println(list) // [a]
println(list.size) // 1
//sampleEnd
}

For JS

Returns an immutable list containing only the specified object element.