RowList.purs

module Type.Proxying.RowList
  ( class GenericRLProxying
  , class RLProxying
  , genericRLProxy
  , rlProxy
  ) where

import Data.Generic.Rep
  ( class Generic
  , Constructor(Constructor)
  , NoArguments(NoArguments)
  , to
  )
import Prim.RowList (kind RowList)
import Type.Data.RowList (RLProxy(RLProxy))
import Type.Proxy (Proxy(Proxy))

class
  Generic (f l) rep
  <= GenericRLProxying (rep :: Type) (f :: RowList -> Type) (l :: RowList)
  where
  genericRLProxy :: Proxy rep ->  f l

instance genericRLProxyingConstructor
  :: Generic (f l) (Constructor proxyName NoArguments)
  => GenericRLProxying (Constructor proxyName NoArguments) f l
  where
  genericRLProxy _ = to (Constructor NoArguments)

class RLProxying (f :: RowList -> Type) (l :: RowList) where
  rlProxy :: f l

instance rlProxying_TypeDataRowList_RLProxy :: RLProxying RLProxy l where
  rlProxy = RLProxy

else instance rlProxying_TypeRow_RLProxy :: RLProxying RLProxy l where
  rlProxy = RLProxy

else instance rlProxyingGeneric
  :: Generic (f l) (Constructor proxyName NoArguments)
  => RLProxying f l
  where
  rlProxy = genericRLProxy (Proxy :: Proxy (Constructor proxyName NoArguments))