flatMap

@JvmName(name = "flatMapIterable")

fun <T, R> Sequence<T>.flatMap(transform: (T) -> Iterable<R>): Sequence<R>

Returns a single sequence of all elements from results of transform function being invoked on each element of original sequence.

The operation is intermediate and stateless.

Since Kotlin

1.4

Samples

import samples.*
import kotlin.test.*
fun main() { 
   //sampleStart 
   val list = listOf("123", "45")
assertPrints(list.flatMap { it.toList() }, "[1, 2, 3, 4, 5]") 
   //sampleEnd
}

fun <T, R> Sequence<T>.flatMap(transform: (T) -> Sequence<R>): Sequence<R>

Returns a single sequence of all elements from results of transform function being invoked on each element of original sequence.

The operation is intermediate and stateless.

Samples

import samples.*
import kotlin.test.*
fun main() { 
   //sampleStart 
   val list = listOf("123", "45")
assertPrints(list.flatMap { it.toList() }, "[1, 2, 3, 4, 5]") 
   //sampleEnd
}