如果我在253行寫成這樣 main :: IO () main = do initCapturing xmonad $ defaultConfig { borderWidth = 3 } xmonad defaults borderWidth = 3會生效。 xmonad.errors 除了上面的,又多出一條 xmonad.hs:263:12: Warning: In the use of ‘defaultConfig’ (imported from XMonad, but defined in XMonad.Config): Deprecated: "Use def (from Data.Default, and re-exported by XMonad and XMonad.Config) instead."