kotlin-stdlib / kotlin.collections / withDefault

withDefault

Common
JVM
JS
Native
1.0
fun <K, V> Map<K, V>.withDefault(
    defaultValue: (key: K) -> V
): Map<K, V>

Returns a wrapper of this read-only map, having the implicit default value provided with the specified function defaultValue.

This implicit default value is used when the original map doesn't contain a value for the key specified and a value is obtained with Map.getValue function, for example when properties are delegated to the map.

When this map already has an implicit default value provided with a former call to withDefault, it is being replaced by this call.

Common
JVM
JS
Native
1.0
@JvmName("withDefaultMutable") fun <K, V> MutableMap<K, V>.withDefault(
    defaultValue: (key: K) -> V
): MutableMap<K, V>

Returns a wrapper of this mutable map, having the implicit default value provided with the specified function defaultValue.

This implicit default value is used when the original map doesn't contain a value for the key specified and a value is obtained with Map.getValue function, for example when properties are delegated to the map.

When this map already has an implicit default value provided with a former call to withDefault, it is being replaced by this call.