Simplify block/wall destruction

This uses a right fold, so might be slower than a strict left fold

src/Dodge/Update/WallDamage.hs

@@ -13,14 +13,23 @@ import Dodge.Zoning.Base
 import Geometry.Data
 import qualified IntMapHelp as IM
 
+--updateWallDamages :: World -> World
+--updateWallDamages w =
+--    let (is, w') = IM.foldlWithKey' f (mempty, w) (w ^. cWorld . lWorld . wallDamages)
+--     in updateEdgesWall is w' & cWorld . lWorld . wallDamages .~ IM.empty
+--  where
+--    f isw k dams = fromMaybe isw $ do
+--        wl <- isw ^? _2 . cWorld . lWorld . walls . ix k
+--        return $ foldl' (flip (`damageWall` wl)) isw dams
+
 updateWallDamages :: World -> World
-updateWallDamages w =
-    let (is, w') = IM.foldlWithKey' f (mempty, w) (w ^. cWorld . lWorld . wallDamages)
-     in updateEdgesWall is w' & cWorld . lWorld . wallDamages .~ IM.empty
+updateWallDamages w = set (cWorld . lWorld . wallDamages) mempty
+    . uncurry updateEdgesWall $ foldrM f w 
+    (IM.toList $ w ^. cWorld . lWorld . wallDamages)
   where
-    f isw k dams = fromMaybe isw $ do
-        wl <- isw ^? _2 . cWorld . lWorld . walls . ix k
-        return $ foldl' (flip (`damageWall` wl)) isw dams
+    f (k,dams) w' = fromMaybe (mempty,w') $ do
+        wl <- w' ^? cWorld . lWorld . walls . ix k
+        return $ foldrM (damageWall wl) w' dams
 
 updateEdgesWall :: S.Set Int2 -> World -> World
 updateEdgesWall is w =