0.2.0: Conformance.

Now you can add conformance to the Valueless flavor:

@WithValueless(conformsTo: ["Codable", "CaseIterable"])
indirect enum Unit {
  case ton, kilogram, gram
  case kilometer, meter, decimeter, centimeter
  case currency(code: String)
  case derived(Unit, power: Int)
  case derived(Unit, by: Unit)
  case custom(String)
}

expands to:

enum ValuelessUnit: Codable, CaseIterable {
  case ton, kilogram, gram
  case kilometer, meter, decimeter, centimeter
  case currencyCodeString
  case derivedUnitPowerInt
  case derivedUnitByUnit
  case customString
}