kotlin-stdlib/kotlin.collections/indices

indices

val <T> Array<out T>.indices: IntRange(source)
val ByteArray.indices: IntRange(source)
val ShortArray.indices: IntRange(source)
val IntArray.indices: IntRange(source)
val LongArray.indices: IntRange(source)
val FloatArray.indices: IntRange(source)
val DoubleArray.indices: IntRange(source)
val BooleanArray.indices: IntRange(source)
val CharArray.indices: IntRange(source)

Returns the range of valid indices for the array.

Since Kotlin

1.0
@ExperimentalUnsignedTypes
val UIntArray.indices: IntRange(source)
@ExperimentalUnsignedTypes
val ULongArray.indices: IntRange(source)
@ExperimentalUnsignedTypes
val UByteArray.indices: IntRange(source)
@ExperimentalUnsignedTypes
val UShortArray.indices: IntRange(source)

Returns the range of valid indices for the array.

Since Kotlin

1.3
val Collection<*>.indices: IntRange(source)

Returns an IntRange of the valid indices for this collection.

Since Kotlin

1.0

Samples

import kotlin.test.*

fun main() { 
   //sampleStart 
   val empty = emptyList<Any>()
println("empty.indices.isEmpty() is ${empty.indices.isEmpty()}") // true
val collection = listOf('a', 'b', 'c')
println(collection.indices) // 0..2 
   //sampleEnd
}