Looking for ideas on how to do this (or anything v...

# getting-started

[jeff]

Looking for ideas on how to do this (or anything vaguely similar) with less boilerplate:

interface HasName {
  val name: String
  fun copy(name: String = name) // boilerplate (but only once)
}

data class Person(
  override val name: String,
  val age: Int
) : HasName {
  override fun copy(name: String = name) // boilerplate (in everything that extends HasName)
}

// Because I want to do this:
val named: HasName = Person(...)
named.copy(name = "newName")

[Joffrey]

I don't see an implementation for copy anywhere. Is the implementation of that method supposed to be different in different implementations of HasName? What "boilerplate" are you trying to get rid of exactly?

[jeff]

Person already has a copy(name=) by virtue of being a data class. But I need to "re-" define it so that the interface can see it

[jeff]

(I understand why, just looking for other options)

[hfhbd]

I use a sealed interface and a extension fun HasName.copy(...) = with (this) { is Person -> copy(...) }