From c495fc064a8e27f8d3f8885a9138c3f4ce288e1c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Madeleine=20Sydney=20=C5=9Alaga?= <msyds@deertopia.net>
Date: Sat, 5 Sep 2026 19:56:10 -0600
Subject: [PATCH] arith prims

---
 src/Gyehoek/CPS/Eval.hs | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/Gyehoek/CPS/Eval.hs b/src/Gyehoek/CPS/Eval.hs
index 1d780d8..f30a3c1 100644
--- a/src/Gyehoek/CPS/Eval.hs
+++ b/src/Gyehoek/CPS/Eval.hs
@@ -211,8 +211,26 @@ eval g dps (ExpLetRec bs e) = do
   traverse_ (uncurry assign) $ zip ls (bs' ^.. each . _2)
   eval g' dps e
 
+eval g dps (ExpPrim p k) = do
+  p' <- evalPrim g =<< traverse (evalVal g) p
+  evalKexp g k >>= \case
+    EProcedure fp -> fp p' dps
+    _ -> wrong [i|prim(#{p})의 계속을 나쁘다|]
+
 eval g dps e = error [i|unimplemented #{e}|]
 
+evalPrim :: Env -> Prim E -> M Answer (List E)
+evalPrim g = \case
+  PrimAdd x y -> arith2 (+) x y
+  PrimMul x y -> arith2 (*) x y
+  PrimSub x y -> arith2 (-) x y
+  PrimDiv x y -> arith2 div x y
+  PrimValues xs -> pure xs
+  p -> wrong [i|prim(#{p})은 벌써 나지 않다|]
+  where
+    arith2 f (EInt x) (EInt y) = pure [EInt $ f x y]
+    arith2 f x y = wrong [i|나쁜 인자: #{x}, #{y}|]
+
 
 
 evalExp :: Jalmot :> es => Exp -> Eff es _