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gyehoek-hs/src/Gyehoek/CPS/Convert.hs
T
2026-07-11 16:25:58 -06:00

64 lines
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Haskell

{-# LANGUAGE OverloadedLists #-}
module Gyehoek.CPS.Convert
( convert
, convertProgram
) where
import Gyehoek.CPS.Syntax
import Gyehoek.Scheme.Syntax qualified as Scm
import Gyehoek.GenSym
import Data.List.NonEmpty (NonEmpty((:|)))
import Effectful
import Control.Monad.Cont qualified as Cont
import Control.Lens
import qualified Data.List.NonEmpty as NE
-- 뻘짓이어라
telescope
:: Traversable t
=> (a -> (b -> r) -> r)
-> t a -> (t b -> r) -> r
telescope f = Cont.runCont . traverse (Cont.cont . f)
convert
:: forall es. (GenSym :> es)
=> Scm.Exp -> (Val -> Eff es Exp) -> Eff es Exp
convert (Scm.ExpVar x) k = k $ ValVar x
convert (Scm.ExpLit l) k = k $ ValLit l
convert (Scm.ExpPrim p) k =
telescope (convert @es) p \p' -> do
r <- gensym' "r"
ExpPrim p' [r] <$> k (ValVar r)
convert (Scm.ExpLambda xs e) k = do
f <- gensym' "λ-body"
ktail <- gensym' "λ-tail"
m <- convert e $ \e' ->
pure $ ExpContinue ktail [e']
ExpLet [(f, MkLambda xs ktail m)] <$> k (ValVar f)
convert (Scm.ExpApply f xs) k =
telescope (convert @es) (f:|xs) \(f':|xs') -> do
r <- gensym' "r"
x <- gensym' "x"
m <- k (ValVar x)
pure $ ExpFix [(r, MkKappa [x] m)] $ ExpApply f' (xs' ++ [ValVar r])
convert (Scm.ExpBegin xs) k = _
convert (Scm.ExpIf c t f) k =
convert c \c' ->
ExpIf c' <$> convert t k <*> convert f k
convert _ k = _
convertProgram :: forall es. (GenSym :> es) => Scm.Program -> Eff es Program
convertProgram p =
MkProgram <$> telescope (convert @es) (p ^.. each . _Left) \exps ->
pure . Halt1 $ case NE.nonEmpty exps of
Nothing -> ValLit Void
Just es -> NE.last es