file.hs

{-# LANGUAGE GeneralizedNewtypeDeriving #-}
import qualified Data.Binary.Get as G

type BGetM = ReaderT SchemaDef G.Get
newtype BGet t a = BGet (BGetM a)
    deriving (Functor, Applicative, Monad)

class Proto t where
    bGetInt32 :: BGet t Int32

class Serializable a where
    bGet :: Proto t => BGet t a

instance Serializable Int32 where
    bGet = bGetInt32

newtype Modifier = Modifier Int32 deriving Serializable