X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FTSN%2FTeam.hs;h=1fef0a3447a2afaa4bfb579d3434bee10421dc7d;hb=9fd3de070901b5591e90406cced64c633cb9ca95;hp=bb73efcf975cf11c949acd92e04db8296eecdae9;hpb=f1ec53a41f9d1fc0761a92476e20f214b9b75d79;p=dead%2Fhtsn-import.git diff --git a/src/TSN/Team.hs b/src/TSN/Team.hs index bb73efc..1fef0a3 100644 --- a/src/TSN/Team.hs +++ b/src/TSN/Team.hs @@ -1,3 +1,4 @@ +{-# LANGUAGE DeriveGeneric #-} {-# LANGUAGE FlexibleInstances #-} {-# LANGUAGE GADTs #-} {-# LANGUAGE QuasiQuotes #-} @@ -14,6 +15,7 @@ -- module TSN.Team ( HTeam(..), + FromXmlFkTeams(..), Team(..), VTeam(..), -- * WARNING: these are private but exported to silence warnings @@ -22,10 +24,16 @@ where -- System imports import Database.Groundhog () -- Required for some String instance +import Database.Groundhog.Core ( PersistEntity(..) ) import Database.Groundhog.TH ( defaultCodegenConfig, groundhog, mkPersist ) +import qualified GHC.Generics as GHC ( Generic ) + +-- Local imports +import Generics ( Generic(..) ) +import Xml ( Child(..), Db(..) ) -- * Team @@ -44,8 +52,11 @@ data Team = -- don't have them for some teams. name :: Maybe String -- ^ Some teams don't even have names! } - deriving (Eq, Show) + deriving (Eq, GHC.Generic, Show) +-- | Needed for 'Generics.to_tuple'. +-- +instance Generic Team -- * VTeam / HTeam @@ -76,3 +87,20 @@ mkPersist defaultCodegenConfig [groundhog| 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