```class NboAdapter( val idAdapter: ColumnAdapter<NboId, String> ... } val nboAdapter...

# getting-started

[ursus]

class NboAdapter(
    val idAdapter: ColumnAdapter<NboId, String>
    ...
}

val nboAdapter = NboAdapter(
	idAdapter = IdColumnAdapter(::NboId), <--------------- do away with ::NboId
    ...
)

class IdColumnAdapter<T : Id>(val factory: (String) -> T) : ColumnAdapter<T, String> {
    override fun decode(databaseValue: String): T = factory(databaseValue)
    override fun encode(value: T): String = value.value
}

interface Id : Comparable<Id> {
    val value: String
    override fun compareTo(other: Id): Int = value.compareTo(other.value)
}

data class NboId(override val value: String) : Id

is there a way to infer the ::NboId constructor? I'm trying maybe with reified but that would require T(value) constructor which is not possible in kotlin/java without reflection, right?

however this does exist

inline fun <reified T : Enum<T>> EnumColumnAdapter(): EnumColumnAdapter<T> {
  return EnumColumnAdapter(enumValues())
}

is that some sort of magic? I thought values was only definied on the concrete enum

[asdf asdf]

It is somewhat magic, as it's implemented as a compiler intrinsic

[asdf asdf]

(jvm implementation:)

[ursus]

okay so I'm out of luck?

[ursus]

or is there a way to help the type inference, to do the ctor

[ursus]

also I'm wondering if I were to not do concrete NboId but turn it around to somethinglike Id<Nbo> , but not sure if that would help yet

[ursus]

well, I know it would, but it has its downsides, so still looking to make the first sample work would be best

[asdf asdf]

I don't believe there is a way to infer a constructor of a reified type unfortunately without reflection

[asdf asdf]

There is a pretty hacky trick like this that could be used, however, its not really recommended as it is unsafe and relies on proper importing

[ursus]

that kinda melts my brain 😄

[ursus]

btw how about value classes, those can have only a single value right? maybe a ctor is accessible there generically?

[asdf asdf]

Don’t think so either unfortunately, at once point was hoping there could be something like a Valued<T> interface that value classes would automatically implement that would allow for generic destructuring of them

[ursus]

EXACTLY, same as the enum magic

[ursus]

Plan B is to run it throught json serializer, kotlinx has a support for value classes but yea thats not great

[ursus]

nevermind, thank you!