-- | Specify a function to show the default value for an option.
showDefaultWith :: (a -> String) -> Mod f a
showDefaultWith s = Mod id (DefaultProp Nothing (Just s)) id
showDefaultWith :: (a -> String) -> Mod f a
showDefaultWith s = Mod id (DefaultProp Nothing (Just s)) id
showDefaultWith s = Mod id (DefaultProp Nothing (Just s)) id