minByOrNull

Common
JVM
JS
Native
1.4
inline fun < R : Comparable < R > > CharSequence . minByOrNull (
selector : ( Char ) -> R
) : Char ?

(source)

Returns the first character yielding the smallest value of the given function or null if there are no characters.

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
}