kotlin-stdlib/kotlin.sequences/lastOrNull

lastOrNull

fun <T> Sequence<T>.lastOrNull(): T?(source)

Returns the last element, or null if the sequence is empty.

The operation is terminal.

Since Kotlin

1.0

Samples

import kotlin.test.*

fun main() { 
   //sampleStart 
   val list = listOf(1, 2, 3, 4)
println(list.last()) // 4
println(list.last { it % 2 == 1 }) // 3
println(list.lastOrNull { it < 0 }) // null
// list.last { it < 0 } // will fail

val emptyList = emptyList<Int>()
println(emptyList.lastOrNull()) // null
// emptyList.last() // will fail 
   //sampleEnd
}
inline fun <T> Sequence<T>.lastOrNull(predicate: (T) -> Boolean): T?(source)

Returns the last element matching the given predicate, or null if no such element was found.

The operation is terminal.

Since Kotlin

1.0

Samples

import kotlin.test.*

fun main() { 
   //sampleStart 
   val list = listOf(1, 2, 3, 4)
println(list.last()) // 4
println(list.last { it % 2 == 1 }) // 3
println(list.lastOrNull { it < 0 }) // null
// list.last { it < 0 } // will fail

val emptyList = emptyList<Int>()
println(emptyList.lastOrNull()) // null
// emptyList.last() // will fail 
   //sampleEnd
}