--
module TSN.Team (
HTeam(..),
+ FromXmlFkTeams(..),
Team(..),
VTeam(..),
-- * WARNING: these are private but exported to silence warnings
-- System imports
import Database.Groundhog () -- Required for some String instance
+import Database.Groundhog.Core ( PersistEntity(..) )
import Database.Groundhog.TH (
defaultCodegenConfig,
groundhog,
mkPersist )
+-- Local imports
+import Xml ( Child(..), Db(..) )
+
-- * Team
type: constraint
fields: [team_id]
|]
+
+
+
+-- | A further refinement of 'FromXmlFk'. These types need not only a
+-- foreign key to a parent in order to make the XML -> DB
+-- conversion, but also two foreign keys to away/home teams (as
+-- represented in "TSN.Team").
+--
+class (Child a, ToDb a) => FromXmlFkTeams a where
+ -- | The function that produces a @Db a@ out of a parent foreign
+ -- key, two team foreign keys, and an @a@. The parameter order makes
+ -- it easier to map this function over a bunch of things.
+ from_xml_fk_teams :: DefaultKey (Parent a)
+ -> DefaultKey Team -- ^ The away team FK
+ -> DefaultKey Team -- ^ The home team FK
+ -> a
+ -> Db a