kotlin-stdlib / kotlin.collections / setValue setValue Common JVM JS Native 1.0 operator fun <V> MutableMap<in String, in V>.setValue( thisRef: Any?, property: KProperty<*>, value: V) Stores the value of the property for the given object in this mutable map. Parameters thisRef - the object for which the value is requested (not used). property - the metadata for the property, used to get the name of property and store the value associated with that name in the map. value - the value to set.