asSequence

import java.util.Optional
import kotlin.jvm.optionals.*

fun main() { 
   //sampleStart 
   val maybeItsAnAnimal = Optional.of("Anonymous Capybara")
val animals = maybeItsAnAnimal.asSequence()
println(animals.joinToString()) // Anonymous Capybara

val maybeItIsNot = Optional.empty<String>()
println(maybeItIsNot.asSequence().joinToString()) // 
   //sampleEnd
}