Kotlin List asSequence()
Syntax & Examples

Syntax of List.asSequence()

The syntax of List.asSequence() extension function is:

fun <T> Iterable<T>.asSequence(): Sequence<T>

This asSequence() extension function of List creates a Sequence instance that wraps the original collection returning its elements when being iterated.

✐ Examples

1 Example

In this example,

We create a list named list1 containing integers from 1 to 5.
We use the asSequence() function to convert list1 into a sequence and store it in sequence.
We convert the sequence back to a list using toList() and print it.
The output is the same as list1, which is [1, 2, 3, 4, 5].

Kotlin Program

fun main(args: Array<String>) {
    val list1 = listOf(1, 2, 3, 4, 5);
    val sequence = list1.asSequence();
    println(sequence.toList());
}

Output

[1, 2, 3, 4, 5]

2 Example

In this example,

We create a list named list2 containing characters 'a' to 'e'.
We use the asSequence() function to convert list2 into a sequence and store it in sequence.
We convert the sequence back to a list using toList() and print it.
The output is the same as list2, which is ['a', 'b', 'c', 'd', 'e'].

Kotlin Program

fun main(args: Array<String>) {
    val list2 = listOf('a', 'b', 'c', 'd', 'e');
    val sequence = list2.asSequence();
    println(sequence.toList());
}

Output

[a, b, c, d, e]

3 Example

In this example,

We create a list named list3 containing strings "apple", "banana", and "cherry".
We use the asSequence() function to convert list3 into a sequence and store it in sequence.
We convert the sequence back to a list using toList() and print it.
The output is the same as list3, which is ["apple", "banana", "cherry"].

Kotlin Program

fun main(args: Array<String>) {
    val list3 = listOf("apple", "banana", "cherry");
    val sequence = list3.asSequence();
    println(sequence.toList());
}

Output

[apple, banana, cherry]

Summary

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