{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE FlexibleContexts #-}
{-# OPTIONS -fno-warn-orphans #-}
module Database.HDBC.SqlValueExtra () where
import Data.Convertible (Convertible(safeConvert), ConvertResult)
import Data.Int (Int8, Int16, Int32)
import Database.HDBC (SqlValue)
safeConvertFromIntegral32 :: Integral a => a -> ConvertResult SqlValue
safeConvertFromIntegral32 i =
safeConvert (fromIntegral i :: Int32)
safeConvertToIntegral32 :: Convertible Int32 a => SqlValue -> ConvertResult a
safeConvertToIntegral32 v =
safeConvert =<< (safeConvert v :: ConvertResult Int32)
instance Convertible Int8 SqlValue where
safeConvert = safeConvertFromIntegral32
instance Convertible SqlValue Int8 where
safeConvert = safeConvertToIntegral32
instance Convertible Int16 SqlValue where
safeConvert = safeConvertFromIntegral32
instance Convertible SqlValue Int16 where
safeConvert = safeConvertToIntegral32