HKDClash.hs

{-# LANGUAGE FlexibleInstances #-}
module HKDClash where

import Clash.Prelude
import Data.Functor.Identity

type family HKD f a where
  HKD Identity a = a
  HKD f        a = f a

data Person' f = Person
  { pName :: HKD f Bool
  , pAge  :: HKD f Int
  }

type Person = Person' Identity

instance Bundle (Person' Identity) where
  type Unbundled dom (Person' Identity) = Person' (Signal dom)
  bundle (Person a b) = Person <$> a <*> b
  unbundle p          = Person (pName <$> p) (pAge <$> p)

topEntity
  :: SystemClockReset
  => Signal System Person
  -> Signal System Person
topEntity p =
  let Person a b = unbundle p
      b' = register 0 (b + 1)
  in  bundle (Person a b')