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Features and Types

A feature declaration is a type-level contract: value type, context type, and namespace type are bound together.

Core Shape​

Feature<T, C, M> means:

  • T: value returned by evaluate(...)
  • C: required context type
  • M: owning namespace type

Built-in Feature Value Kinds​

  • boolean<Context>(default = false)
  • string<Context>(default = "...")
  • integer<Context>(default = 0)
  • double<Context>(default = 0.0)
  • enum<MyEnum, Context>(default = MyEnum.X)
  • custom<MyKonstrainedType, Context>(default = MyKonstrainedType(...))

Example​

enum class CheckoutVariant { CLASSIC, SMART }

object AppFeatures : Namespace("app") {
  val darkMode by boolean<Context>(default = false)
  val retryLimit by integer<Context>(default = 3)
  val checkoutVariant by enum<CheckoutVariant, Context>(default = CheckoutVariant.CLASSIC)
}

Trade-off​

You get compile-time guarantees only for declared features. Dynamic feature creation at runtime is intentionally outside this model.

Next Steps​