1 -- | This module defines the 'Configuration' type, which is just a
2 -- wrapper around all of the configuration options we accept on the
10 import System.Console.CmdArgs.Default ( Default(..) )
12 import qualified OptionalConfiguration as OC (
13 OptionalConfiguration(..),
16 -- | The main configuration data type. This will be passed to most of
17 -- the important functions once it has been created.
22 database :: Maybe String,
25 password :: Maybe String,
27 username :: Maybe String }
30 -- | A Configuration with all of its fields set to their default
32 instance Default Configuration where
42 -- | Merge a 'Configuration' with an 'OptionalConfiguration'. This is
43 -- more or less the Monoid instance for 'OptionalConfiguration', but
44 -- since the two types are different, we have to repeat ourselves.
45 merge_optional :: Configuration
46 -> OC.OptionalConfiguration
48 merge_optional cfg opt_cfg =
50 (merge (both cfg) (OC.both opt_cfg))
51 (OC.merge_maybes (database cfg) (OC.database opt_cfg))
52 (merge (detail cfg) (OC.detail opt_cfg))
53 (OC.merge_maybes (host cfg) (OC.host opt_cfg))
54 (OC.merge_maybes (password cfg) (OC.password opt_cfg))
55 (OC.merge_maybes (port cfg) (OC.port opt_cfg))
56 (OC.merge_maybes (username cfg) (OC.username opt_cfg))
58 -- | If the thing on the right is Just something, return that
59 -- something, otherwise return the thing on the left.
60 merge :: a -> Maybe a -> a