Move wall damages to external position

src/Dodge/Update/WallDamage.hs

@@ -0,0 +1,16 @@
+module Dodge.Update.WallDamage where
+import Dodge.Wall.Damage
+import Dodge.Data
+
+import qualified Data.IntMap.Strict as IM
+import Control.Lens
+import Data.Maybe
+
+updateWallDamages :: World -> World
+updateWallDamages w = w
+    & wallDamages .~ IM.empty
+    & flip (IM.foldrWithKey f) (_wallDamages w)
+  where
+    f k dams w' = fromMaybe w' $ do
+        wl <- w' ^? walls . ix k
+        return $ foldr (flip damageWall wl) w' dams