diff --git a/2021/day13.hs b/2021/day13.hs
index 91d01bd..125e579 100644
--- a/2021/day13.hs
+++ b/2021/day13.hs
@@ -14,8 +14,8 @@ parseFold :: String -> Fold
 parseFold s = if axis == "x" then Horizontal (read line) else Vertical (read line) where [axis,line] = splitOn "=" $ last (words s)
 
 fold :: Fold -> Dot -> Dot
-fold fold@(Vertical f)   (x,y) = (x, if y > f then f - (y-f) else y)
-fold fold@(Horizontal f) (x,y) = (if x > f then f - (x-f) else x, y)
+fold (Vertical f)   (x,y) = (x, if y > f then f - (y-f) else y)
+fold (Horizontal f) (x,y) = (if x > f then f - (x-f) else x, y)
 
 main :: IO ()
 main = do