kotlin-stdlib/kotlin.collections/MutableMap/remove

remove

expect abstract fun remove(key: K): V?(source)

Removes the specified key and its corresponding value from this map.

Since Kotlin

1.0

Return

the previous value associated with the key, or null if the key was not present in the map.

Samples

import kotlin.test.*
import java.util.*

fun main() { 
   //sampleStart 
   val map = mutableMapOf(1 to "one", 2 to "two")

assertEquals("one", map.remove(1))
println(map) // {2=two}

// There's no value for key=1 anymore
assertNull(map.remove(1)) 
   //sampleEnd
}
actual abstract fun remove(key: K): V?(source)

Removes the specified key and its corresponding value from this map.

Since Kotlin

1.1

Return

the previous value associated with the key, or null if the key was not present in the map.

Samples

import kotlin.test.*
import java.util.*

fun main() { 
   //sampleStart 
   val map = mutableMapOf(1 to "one", 2 to "two")

assertEquals("one", map.remove(1))
println(map) // {2=two}

// There's no value for key=1 anymore
assertNull(map.remove(1)) 
   //sampleEnd
}
actual abstract fun remove(key: K): V?(source)

Removes the specified key and its corresponding value from this map.

Since Kotlin

1.3

Return

the previous value associated with the key, or null if the key was not present in the map.

Samples

import kotlin.test.*
import java.util.*

fun main() { 
   //sampleStart 
   val map = mutableMapOf(1 to "one", 2 to "two")

assertEquals("one", map.remove(1))
println(map) // {2=two}

// There's no value for key=1 anymore
assertNull(map.remove(1)) 
   //sampleEnd
}
actual abstract fun remove(key: K): V?(source)

Removes the specified key and its corresponding value from this map.

Since Kotlin

1.8

Return

the previous value associated with the key, or null if the key was not present in the map.

Samples

import kotlin.test.*
import java.util.*

fun main() { 
   //sampleStart 
   val map = mutableMapOf(1 to "one", 2 to "two")

assertEquals("one", map.remove(1))
println(map) // {2=two}

// There's no value for key=1 anymore
assertNull(map.remove(1)) 
   //sampleEnd
}
actual abstract fun remove(key: K): V?(source)

Removes the specified key and its corresponding value from this map.

Since Kotlin

1.8

Return

the previous value associated with the key, or null if the key was not present in the map.

Samples

import kotlin.test.*
import java.util.*

fun main() { 
   //sampleStart 
   val map = mutableMapOf(1 to "one", 2 to "two")

assertEquals("one", map.remove(1))
println(map) // {2=two}

// There's no value for key=1 anymore
assertNull(map.remove(1)) 
   //sampleEnd
}