ToStringy.hs

{-# LANGUAGE
    FlexibleContexts
  , FlexibleInstances
  , MultiParamTypeClasses
  , TypeSynonymInstances
  #-}
module ToStringy (ToStringy (..), fromStringy) where

import Data.String
import qualified Data.ByteString           as SB
import qualified Data.ByteString.Lazy      as LB
import qualified Data.ByteString.Lazy.UTF8 as LBU
import qualified Data.ByteString.UTF8      as SBU
import qualified Data.Text                 as ST
import qualified Data.Text.Encoding        as STE
import qualified Data.Text.Lazy            as LT
import qualified Data.Text.Lazy.Encoding   as LTE

class ToStringy a b where
  toStringy :: a -> b

instance ToStringy LB.ByteString LT.Text       where toStringy = LTE.decodeUtf8
instance ToStringy LB.ByteString SB.ByteString where toStringy = LB.toStrict
instance ToStringy LB.ByteString ST.Text       where toStringy = LT.toStrict . LTE.decodeUtf8
instance ToStringy LB.ByteString String        where toStringy = LBU.toString
instance ToStringy LT.Text       LB.ByteString where toStringy = LTE.encodeUtf8
instance ToStringy LT.Text       SB.ByteString where toStringy = LB.toStrict . LTE.encodeUtf8
instance ToStringy LT.Text       ST.Text       where toStringy = LT.toStrict
instance ToStringy LT.Text       String        where toStringy = LT.unpack
instance ToStringy SB.ByteString LB.ByteString where toStringy = LB.fromStrict
instance ToStringy SB.ByteString LT.Text       where toStringy = LTE.decodeUtf8 . LB.fromStrict
instance ToStringy SB.ByteString ST.Text       where toStringy = STE.decodeUtf8
instance ToStringy SB.ByteString String        where toStringy = SBU.toString
instance ToStringy ST.Text       LB.ByteString where toStringy = LTE.encodeUtf8 . LT.fromStrict
instance ToStringy ST.Text       LT.Text       where toStringy = LT.fromStrict
instance ToStringy ST.Text       SB.ByteString where toStringy = STE.encodeUtf8
instance ToStringy ST.Text       String        where toStringy = ST.unpack
instance ToStringy String        LB.ByteString where toStringy = LBU.fromString
instance ToStringy String        LT.Text       where toStringy = LT.pack
instance ToStringy String        SB.ByteString where toStringy = SBU.fromString
instance ToStringy String        ST.Text       where toStringy = ST.pack

fromStringy :: (ToStringy a String, IsString b) => a -> b
fromStringy = fromString . toStringy