Remove a lot of IO/maybe cruft

src/Dodge/Event/Keyboard.hs

@@ -47,9 +47,9 @@ On release, remove scancode from the 'Set' of pressed keys.
 On press, adds the scancode, and perhaps applies a direct effect:
 see 'handlePressedKeyInGame'.
 -}
-handleKeyboardEvent :: KeyboardEventData -> Universe -> IO (Maybe Universe)
+handleKeyboardEvent :: KeyboardEventData -> Universe -> Universe
 handleKeyboardEvent kev u = case keyboardEventKeyMotion kev of
-    Released -> return . Just $ u & uvWorld . input . pressedKeys . at scode .~ Nothing
+    Released -> u & uvWorld . input . pressedKeys . at scode .~ Nothing
     Pressed ->
         handlePressedKey
             (keyboardEventRepeat kev)
@@ -61,17 +61,17 @@ handleKeyboardEvent kev u = case keyboardEventKeyMotion kev of
         | otherwise = InitialPress
     scode = (keysymScancode . keyboardEventKeysym) kev
 
-handlePressedKey :: Bool -> Scancode -> Universe -> IO (Maybe Universe)
-handlePressedKey True _ u = return $ Just u
+handlePressedKey :: Bool -> Scancode -> Universe -> Universe
+handlePressedKey True _ u = u
 handlePressedKey _ scode u = case scode of
-    ScancodeF5 -> return . Just $ doQuicksave u
-    ScancodeF9 -> return . Just $ loadSaveSlot QuicksaveSlot u
-    ScancodeSemicolon -> return . Just $ gotoTerminal u
+    ScancodeF5 -> doQuicksave u
+    ScancodeF9 -> loadSaveSlot QuicksaveSlot u
+    ScancodeSemicolon -> gotoTerminal u
     _ | null (_uvScreenLayers u) -> case u ^? uvWorld . cWorld . lWorld . hud . hudElement . subInventory of
         Just (DisplayTerminal tmid)
             | inTermFocus (_uvWorld u) ->
-                return $ uvWorld (Just . handlePressedKeyTerminal tmid scode) u
-        _ -> return $ Just u
+                over uvWorld (handlePressedKeyTerminal tmid scode) u
+        _ -> u
     _ -> handlePressedKeyInMenu (head $ _uvScreenLayers u) scode u
 
 handlePressedKeyTerminal :: Int -> Scancode -> World -> World

src/Dodge/Event/Menu.hs

@@ -8,24 +8,23 @@ import Dodge.Data.Universe
 import Dodge.WindowLayout
 import SDL
 
-handlePressedKeyInMenu :: ScreenLayer -> Scancode -> Universe -> IO (Maybe Universe)
+handlePressedKeyInMenu :: ScreenLayer -> Scancode -> Universe -> Universe
 handlePressedKeyInMenu mState scode = case mState of
     OptionScreen{_scOptions = mos, _scDefaultEff = defeff} ->
         optionListToEffects defeff scode mos
     --DisplayScreen{} -> popScreen
 --    WaitScreen{} -> return . Just
-    _ -> return . Just
+    _ -> id
 
 optionListToEffects ::
-    (Universe -> IO (Maybe Universe)) ->
+    (Universe -> Universe) ->
     Scancode ->
     [MenuOption] ->
     Universe ->
-    IO (Maybe Universe)
+    Universe
 optionListToEffects defaulteff sc mops u = case sc of
     ScancodeSpace ->
-        return . Just
-            . (uvScreenLayers . ix 0 . scOptionsOffset %~ (f . (+ mlines)))
+            (uvScreenLayers . ix 0 . scOptionsOffset %~ (f . (+ mlines)))
             $ u
     _ ->
         ( fromMaybe defaulteff
@@ -40,7 +39,7 @@ optionListToEffects defaulteff sc mops u = case sc of
         | otherwise = x
     mlines = availableMenuLines $ _uvConfig u
 
-menuOptionToEffects :: MenuOption -> [(Scancode, Universe -> IO (Maybe Universe))]
+menuOptionToEffects :: MenuOption -> [(Scancode, Universe -> Universe)]
 menuOptionToEffects Toggle{_moKey = k, _moEff = eff} = [(k, eff)]
 menuOptionToEffects InvisibleToggle{_moKey = k, _moEff = eff} = [(k, eff)]
 menuOptionToEffects