Kotlin List indices
Syntax & Examples

Syntax of List.indices

The syntax of List.indices extension property is:

val Collection<*>.indices: IntRange

This indices extension property of List returns an IntRange of the valid indices for this collection.

✐ Examples

1 Example

In this example,

We create a list named list1 containing the characters 'a', 'p', 'p', 'l', 'e'.
We access the indices of list1 using the indices property, which returns an IntRange representing the valid indices for the list.
We store the indices in a variable named indices.
Finally, we print the indices to standard output using println.

Kotlin Program

fun main(args: Array<String>) {
    val list1 = listOf(&quot;a&quot;, &quot;p&quot;, &quot;p&quot;, &quot;l&quot;, &quot;e&quot;);
    val indices = list1.indices;
    println(indices);
}

Output

0..4

2 Example

In this example,

We create a list named list1 containing the integers 10, 20, 30.
We access the indices of list1 using the indices property, which returns an IntRange representing the valid indices for the list.
We store the indices in a variable named indices.
Finally, we print the indices to standard output using println.

Kotlin Program

fun main(args: Array<String>) {
    val list1 = listOf(10, 20, 30);
    val indices = list1.indices;
    println(indices);
}

Output

0..2

3 Example

In this example,

We create a list named list1 containing the integers 10, 20, 30.
We create a sub-list of list1 using the subList function, containing elements at indices 1 and 2.
We access the indices of the sub-list using the indices property, which returns an IntRange representing the valid indices for the sub-list.
We store the indices in a variable named indices.
Finally, we print the indices to standard output using println.

Kotlin Program

fun main(args: Array<String>) {
    val list1 = listOf(10, 20, 30);
    val indices = list1.subList(1, 3).indices;
    println(indices);
}

Output

0..1

Summary

In this Kotlin tutorial, we learned about indices extension property of List: the syntax and few working examples with output and detailed explanation for each example.