kotlin-stdlib / kotlin.text / filterIndexed

filterIndexed

Common
JVM
JS
Native
1.0
inline fun CharSequence.filterIndexed(
    predicate: (index: Int, Char) -> Boolean
): CharSequence
(source)

Returns a char sequence containing only those characters from the original char sequence that match 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 a character and the character itself and returns the result of predicate evaluation on the character.

Common
JVM
JS
Native
1.0
inline fun String.filterIndexed(
    predicate: (index: Int, Char) -> Boolean
): String
(source)

Returns a string containing only those characters from the original string that match 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 a character and the character itself and returns the result of predicate evaluation on the character.