[xmonad] change Layout to `l' in XConfig?

Hi, Can we use more general type in XConfig definition? $ darcs w XMonad/Core.hs What's new in "XMonad/Core.hs": { hunk ./XMonad/Core.hs 75 - , keys :: XConfig Layout -> M.Map (ButtonMask,KeySym) (X ()) - , mouseBindings :: XConfig Layout -> M.Map (ButtonMask, Button) (Window -> X ()) + , keys :: XConfig l -> M.Map (ButtonMask,KeySym) (X ()) + , mouseBindings :: XConfig l -> M.Map (ButtonMask, Button) (Window -> X ()) } Thanks! -- vvv