kotlin-stdlib/kotlin.collections/MutableMap/remove

remove

@IgnorableReturnValue
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")

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

// There's no value for key=1 anymore
println("map.remove(1) == null is ${map.remove(1) == null}") // true 
   //sampleEnd
}
@IgnorableReturnValue
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")

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

// There's no value for key=1 anymore
println("map.remove(1) == null is ${map.remove(1) == null}") // true 
   //sampleEnd
}
@IgnorableReturnValue
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")

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

// There's no value for key=1 anymore
println("map.remove(1) == null is ${map.remove(1) == null}") // true 
   //sampleEnd
}
@IgnorableReturnValue
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")

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

// There's no value for key=1 anymore
println("map.remove(1) == null is ${map.remove(1) == null}") // true 
   //sampleEnd
}
@IgnorableReturnValue
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")

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

// There's no value for key=1 anymore
println("map.remove(1) == null is ${map.remove(1) == null}") // true 
   //sampleEnd
}