kotlin-stdlib/kotlin.collections/HashSet/add

add

expect open override fun add(element: E): Boolean(source)

Adds the specified element to the set.

Since Kotlin

1.0

Return

true if the element has been added, false if the element is already contained in the set.

Samples

import kotlin.math.*
import kotlin.test.*

fun main() { 
   //sampleStart 
   val set = mutableSetOf('a', 'b', 'c')
// Sets do not support duplicates, so there is no way to add yet another 'c'
println("set.add('c') is ${set.add('c')}") // false
println(set) // [a, b, c] 
   //sampleEnd
}
actual open override fun add(element: E): Boolean(source)

Adds the specified element to the collection.

Since Kotlin

1.1

Return

true if the element has been added, false if the collection does not support duplicates and the element is already contained in the collection.

Samples

import kotlin.math.*
import kotlin.test.*

fun main() { 
   //sampleStart 
   val set = mutableSetOf('a', 'b', 'c')
// Sets do not support duplicates, so there is no way to add yet another 'c'
println("set.add('c') is ${set.add('c')}") // false
println(set) // [a, b, c] 
   //sampleEnd
}
import kotlin.math.*
import kotlin.test.*

fun main() { 
   //sampleStart 
   val list = mutableListOf('a', 'b', 'c')
println("list.add('c') is ${list.add('c')}") // true
println(list) // [a, b, c, c] 
   //sampleEnd
}
actual open override fun add(element: E): Boolean(source)

Adds the specified element to the set.

Since Kotlin

1.3

Return

true if the element has been added, false if the element is already contained in the set.

Samples

import kotlin.math.*
import kotlin.test.*

fun main() { 
   //sampleStart 
   val set = mutableSetOf('a', 'b', 'c')
// Sets do not support duplicates, so there is no way to add yet another 'c'
println("set.add('c') is ${set.add('c')}") // false
println(set) // [a, b, c] 
   //sampleEnd
}
actual open override fun add(element: E): Boolean(source)

Adds the specified element to the set.

Since Kotlin

1.8

Return

true if the element has been added, false if the element is already contained in the set.

Samples

import kotlin.math.*
import kotlin.test.*

fun main() { 
   //sampleStart 
   val set = mutableSetOf('a', 'b', 'c')
// Sets do not support duplicates, so there is no way to add yet another 'c'
println("set.add('c') is ${set.add('c')}") // false
println(set) // [a, b, c] 
   //sampleEnd
}
actual open override fun add(element: E): Boolean(source)

Adds the specified element to the set.

Since Kotlin

1.8

Return

true if the element has been added, false if the element is already contained in the set.

Samples

import kotlin.math.*
import kotlin.test.*

fun main() { 
   //sampleStart 
   val set = mutableSetOf('a', 'b', 'c')
// Sets do not support duplicates, so there is no way to add yet another 'c'
println("set.add('c') is ${set.add('c')}") // false
println(set) // [a, b, c] 
   //sampleEnd
}