minByOrNull
Returns the first element yielding the smallest value of the given function or null if there are no elements.
The operation is terminal.
import kotlin.test.*
fun main(args: Array<String>) {
//sampleStart
val list = listOf("abcd", "abc", "ab", "abcde")
val shortestString = list.minByOrNull { it.length }
println(shortestString) // ab
val emptyList = emptyList<String>()
val emptyMin = emptyList.minByOrNull { it.length }
println(emptyMin) // null
//sampleEnd
}