{-# LANGUAGE GHC2024, TemplateHaskell, DerivingStrategies #-}

module INTx where

import GHC.TypeLits (Nat, KnownNat)
import qualified Language.Haskell.TH              as TH

-- | ABI integer value types, where @s@ is for signess and @n@ is the multiple of 8 bits
newtype INTx (s :: Bool) (n :: Nat) = INT Integer deriving newtype (Eq, Ord, Enum)

-- | A constraint that restricts what Nat values are valid for 'INTx'.
class KnownNat n => ValidINTn n

-- | A top-level splice that declares all the valid INTx n values.
flip foldMap [1..32] $ \i -> [d| instance ValidINTn $(TH.litT (TH.numTyLit i)) |]