Kotlin Tutorials

Kotlin Set drop()
Syntax & Examples

Set.drop() extension function

The drop() extension function for sets in Kotlin returns a list containing all elements of the set except the first n elements.

Syntax of Set.drop()

The syntax of Set.drop() extension function is:

fun <T> Set<T>.drop(n: Int): List<T>

This drop() extension function of Set returns a list containing all elements except the first n elements.

Parameters

ParameterOptional/RequiredDescription
nrequiredThe number of elements to drop from the beginning of the set.

Return Type

Set.drop() returns value of type List.


✐ Examples

1 Using drop() to skip the first 2 elements of a set

In Kotlin, we can use the drop() function to get a list of elements from a set, excluding the first 2 elements.

For example,

  1. Create a set of integers.
  2. Use the drop() function to skip the first 2 elements.
  3. Print the resulting list to the console using the println function.

Kotlin Program

fun main(args: Array<String>) {
    val numbers = setOf(1, 2, 3, 4, 5)
    val droppedNumbers = numbers.drop(2)
    println("Elements after dropping the first 2: $droppedNumbers")
}

Output

Elements after dropping the first 2: [3, 4, 5]

2 Using drop() with a set of strings

In Kotlin, we can use the drop() function to get a list of elements from a set of strings, excluding the first 3 elements.

For example,

  1. Create a set of strings.
  2. Use the drop() function to skip the first 3 elements.
  3. Print the resulting list to the console using the println function.

Kotlin Program

fun main(args: Array<String>) {
    val fruits = setOf("apple", "banana", "cherry", "date", "elderberry")
    val droppedFruits = fruits.drop(3)
    println("Elements after dropping the first 3: $droppedFruits")
}

Output

Elements after dropping the first 3: [date, elderberry]

3 Using drop() with an empty set

In Kotlin, we can use the drop() function on an empty set, which will return an empty list regardless of the number of elements to drop.

For example,

  1. Create an empty set of integers.
  2. Use the drop() function to skip the first 2 elements.
  3. Print the resulting list to the console using the println function.

Kotlin Program

fun main(args: Array<String>) {
    val emptySet = emptySet<Int>()
    val droppedElements = emptySet.drop(2)
    println("Elements after dropping the first 2 in empty set: $droppedElements")
}

Output

Elements after dropping the first 2 in empty set: []

Summary

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