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filterIndexed

Platform and version requirements: JVM (1.0), JS (1.0), Native (1.0)
fun <T> Sequence<T>.filterIndexed(
    predicate: (index: Int, T) -> Boolean
): Sequence<T>

Returns a sequence containing only elements matching the given predicate.

import kotlin.test.*

fun main(args: Array<String>) {
//sampleStart
val numbers: List<Int> = listOf(0, 1, 2, 3, 4, 8, 6)
val numbersOnSameIndexAsValue = numbers.filterIndexed { index, i -> index == i }

println(numbersOnSameIndexAsValue) // [0, 1, 2, 3, 4, 6]
//sampleEnd
}

Parameters

predicate -

function that takes the index of an element and the element itself and returns the result of predicate evaluation on the element.

The operation is intermediate and stateless.

© 2010–2020 JetBrains s.r.o. and Kotlin Programming Language contributors
Licensed under the Apache License, Version 2.0.
https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.sequences/filter-indexed.html