flatMap

Common
JVM
JS
Native
1.0
inline fun < R > CharSequence . flatMap (
transform : ( Char ) -> Iterable < R >
) : List < R >

(source)

Returns a single list of all elements yielded from results of transform function being invoked on each character of original char sequence.

import kotlin.test.*

fun main(args: Array<String>) {
//sampleStart
val list = listOf("123", "45")
println(list.flatMap { it.toList() }) // [1, 2, 3, 4, 5]
//sampleEnd
}