maxByOrNull

inline fun <R : Comparable<R>> CharSequence.maxByOrNull(selector: (Char) -> R): Char?

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

Since Kotlin

1.4

Samples

import samples.*
import kotlin.test.*
fun main() { 
   //sampleStart 
   val nameToAge = listOf("Alice" to 42, "Bob" to 28, "Carol" to 51)
val oldestPerson = nameToAge.maxByOrNull { it.second }
assertPrints(oldestPerson, "(Carol, 51)")

val emptyList = emptyList<Pair<String, Int>>()
val emptyMax = emptyList.maxByOrNull { it.second }
assertPrints(emptyMax, "null") 
   //sampleEnd
}