Files
rlp/src/Misc/Lift1.hs
crumbtoo d3bcbf9624 things
2024-02-22 14:05:29 -07:00

42 lines
1.2 KiB
Haskell

{-# LANGUAGE TemplateHaskell #-}
module Misc.Lift1
( Lift1(..)
, liftCon, liftCon2, liftCon3
, Lift(..)
)
where
--------------------------------------------------------------------------------
import Language.Haskell.TH hiding (Type, Name)
import Language.Haskell.TH.Syntax hiding (Type, Name)
import Language.Haskell.TH.Syntax qualified as TH
import Language.Haskell.TH.Quote
import Data.Kind qualified
import GHC.Generics
import Data.Fix
--------------------------------------------------------------------------------
class Lift1 (f :: Data.Kind.Type -> Data.Kind.Type) where
lift1 :: (Quote m, Lift t) => f t -> m Exp
liftCon :: Quote m => TH.Name -> m Exp -> m Exp
liftCon n = fmap (AppE (ConE n))
liftCon2 :: Quote m => TH.Name -> m Exp -> m Exp -> m Exp
liftCon2 n a b = do
a' <- a
b' <- b
pure $ ConE n `AppE` a' `AppE` b'
liftCon3 :: Quote m => TH.Name -> m Exp -> m Exp -> m Exp -> m Exp
liftCon3 n a b c = do
a' <- a
b' <- b
c' <- c
pure $ ConE n `AppE` a' `AppE` b' `AppE` c'
instance Lift1 f => Lift (Fix f) where
lift (Fix f) = AppE (ConE 'Fix) <$> lift1 f