@@ -41,8 +41,11 @@ import qualified Data.Text.Lazy as Lazy ( Text )
4141import Data.Time.Clock ( DiffTime, NominalDiffTime )
4242
4343
44+-- | The class of 'DBType's that form a semigroup. This class is purely a Rel8
45+-- concept, and exists to mirror the 'Semigroup' class.
4446type DBSemigroup :: Type -> Constraint
4547class DBType a => DBSemigroup a where
48+ -- | An associative operation.
4649 (<>.) :: Expr a -> Expr a -> Expr a
4750 infixr 6 <>.
4851