where
import qualified Data.Configurator as DC
-import qualified Data.Configurator.Types as DCT
+
import Data.Data (Data)
import Data.Maybe (fromMaybe)
import Data.Monoid (Monoid(..))
import Data.Typeable (Typeable)
+import Usernames
+
+
-- | The same as Cfg, except everything is optional. It's easy to
-- merge two of these by simply dropping the Nothings in favor of
-- the Justs. The 'usernames' are left un-maybed so that cmdargs
from_address :: Maybe String,
to_address :: Maybe String,
verbose :: Maybe Bool,
- usernames :: [String] }
+ usernames :: Usernames }
deriving (Show, Data, Typeable)
instance Monoid OptionalCfg where
Nothing
Nothing
Nothing
- []
+ (Usernames [])
cfg1 `mappend` cfg2 =
OptionalCfg
(merge (from_address cfg1) (from_address cfg2))
(merge (to_address cfg1) (to_address cfg2))
(merge (verbose cfg1) (verbose cfg2))
- (usernames cfg2) -- Use only the usernames from cfg2
+ all_usernames
where
merge :: (Maybe a) -> (Maybe a) -> (Maybe a)
merge Nothing Nothing = Nothing
merge Nothing (Just x) = Just x
merge (Just _) (Just y) = Just y
-
-instance DCT.Configured [String] where
- convert (DCT.List xs) =
- mapM convert_string xs
- where
- convert_string :: DCT.Value -> Maybe String
- convert_string = DCT.convert
-
- convert _ = Nothing
+ -- Use only the latter usernames if there are any.
+ all_usernames =
+ usernames $ if (null (get_usernames (usernames cfg2)))
+ then cfg1
+ else cfg2
from_rc :: IO OptionalCfg
from_rc = do
cfg_from_address
cfg_to_address
cfg_verbose
- (fromMaybe [] cfg_usernames)
+ (fromMaybe (Usernames []) cfg_usernames)