Kotlin: enums with associated values; function inside 'enum entry' gets `unresolved reference` error

I need to create a list of events with a string as name and a list of pairs as properties, some events properties are the static value, some need dynamically changed, so I create specific functions inside the enum entry to update it but complied with error unresolved reference:

Actually, what I want to implement is a list of enums with associated values, something like these articles mentioned:

• KT-4075 Allow setters overloading for properties, or
• Kotlin: single property with multiple setters of different types, or
• Using Kotlin’s sealed class to approximate Swift’s enum with associated data

Because I have more than 100 events, 95% of them are static, only several of them need to be updated during runtime, so sealed class might not suit my situation:

    enum class Event(val eventName: String, vararg eventProperties: Pair<String, String?>) {
        LOGIN_CLICKED("Login", ("View" to "button clicked")),

        LOGIN_SUCCEED("Login", ("Type" to "succeed")),

        LOGIN_ERROR("Login") {
            fun errorMessage(errorMessage: String) {
                eventProperties = listOf("ErrorType" to errorMessage)
            }
        },

        // ... some other events

        LIST_ITEM_CLICKED("LIST") {
            fun listItemName(itemName: String) {
                eventProperties = listOf("View" to itemName)
            }
        };

        var eventProperties: List<Pair<String, String?>>? = listOf(*eventProperties)


// Although this approach can fix my problem, but I don't prefer it,
// because these functions are only meaningful to specific enum item,
// I don't want them be opened to all enum items.
//
//        fun errorMessage(errorMessage: String) {
//            eventProperties = listOf("ErrorType" to errorMessage)
//        }

//        fun listItemName(itemName: String) {
//            eventProperties = listOf("View" to itemName)
//        }
    }

    fun main(args: Array<String>) {

        // unresolved reference
        println(Event.LOGIN_ERROR.eventProperties)
        Event.LOGIN_ERROR.errorMessage("error password")
        println(Event.LOGIN_ERROR.eventProperties)
    }