Generics are great but when building code that uses runtime type information the compiler sometimes needs to be told to shut up smile In this case involving enums however I can t get it to do so without using reflection ``` when v is Enum lt gt gt val ev Enum lt gt = v val kc KClass lt Enum lt gt gt = ev javaClass kotlin val ser EnumSerializer lt gt = EnumSerializer kc EnumSerializer class primaryConstructor call kc ``` Does anybody know a combination of casts suppressions magical incantations that could allow the commented out line to work

Generics are great, but when building code that uses runtime type information the compiler sometimes needs to be told to shut up 😄 In this case involving enums, however, I can't get it to do so without using reflection:

when (v) {
            is Enum<*> -> {
                val ev: Enum<*> = v
                val kc: KClass<Enum<*>> = ev.javaClass.kotlin
                val ser: EnumSerializer<*> =
//                        EnumSerializer(kc)
                        EnumSerializer::class.primaryConstructor!!.call(kc)

Does anybody know a combination of casts/suppressions/*/magical incantations that could allow the commented out line to work?

class EnumSerializer<T : Enum<T>>(serializableClass: KClass<T>)

hudsonb

11/30/2018, 1:07 PM

EnumSerializer<Nothing>(kc)

work?

bartvh

11/30/2018, 1:12 PM

EnumSerializer(kc as KClass<Nothing>)

does 🙂

hudsonb

11/30/2018, 1:14 PM

Nice, I had a similar question yesterday and someone pointed out that

Nothing

is great for shutting up the compiler 😆

bartvh

11/30/2018, 1:14 PM

Good to know, I'll try to use that instead of <*> and see what it does

Although I appreciate type-safety (always have, but increasingly so as I get older and more experienced) I think Kotlin should just allow dropping into raw-type mode for cases like this

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