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maxBy

Platform and version requirements: JVM (1.0), JS (1.0), Native (1.0)
inline fun <T, R : Comparable<R>> Sequence<T>.maxBy(
    selector: (T) -> R
): T?

Returns the first element yielding the largest 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 nameToAge = listOf("Alice" to 42, "Bob" to 28, "Carol" to 51)
val oldestPerson = nameToAge.maxBy { it.second }
println(oldestPerson) // (Carol, 51)

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

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Licensed under the Apache License, Version 2.0.
https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.sequences/max-by.html