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filterIndexedTo

Platform and version requirements: JVM (1.0), JS (1.0), Native (1.0)
inline fun <T, C : MutableCollection<in T>> Array<out T>.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, T) -> Boolean
): C
inline fun <C : MutableCollection<in Byte>> ByteArray.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, Byte) -> Boolean
): C
inline fun <C : MutableCollection<in Short>> ShortArray.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, Short) -> Boolean
): C
inline fun <C : MutableCollection<in Int>> IntArray.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, Int) -> Boolean
): C
inline fun <C : MutableCollection<in Long>> LongArray.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, Long) -> Boolean
): C
inline fun <C : MutableCollection<in Float>> FloatArray.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, Float) -> Boolean
): C
inline fun <C : MutableCollection<in Double>> DoubleArray.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, Double) -> Boolean
): C
inline fun <C : MutableCollection<in Boolean>> BooleanArray.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, Boolean) -> Boolean
): C
inline fun <C : MutableCollection<in Char>> CharArray.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, Char) -> Boolean
): C
inline fun <T, C : MutableCollection<in T>> Iterable<T>.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, T) -> Boolean
): C
@ExperimentalUnsignedTypes inline fun <C : MutableCollection<in UInt>> UIntArray.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, UInt) -> Boolean
): C
@ExperimentalUnsignedTypes inline fun <C : MutableCollection<in ULong>> ULongArray.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, ULong) -> Boolean
): C
@ExperimentalUnsignedTypes inline fun <C : MutableCollection<in UByte>> UByteArray.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, UByte) -> Boolean
): C
@ExperimentalUnsignedTypes inline fun <C : MutableCollection<in UShort>> UShortArray.filterIndexedTo(
    destination: C, 
    predicate: (index: Int, UShort) -> Boolean
): C

Appends all elements matching the given predicate to the given destination.

import kotlin.test.*

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

println(numbersOnSameIndexAsValue) // []

numbers.filterIndexedTo(numbersOnSameIndexAsValue) { 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.

© 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.collections/filter-indexed-to.html