src/Crypto/Hash/Types/Digest/Read.hs


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{-# OPTIONS_GHC -fno-warn-orphans #-}
{-# LANGUAGE InstanceSigs          #-}
{-# LANGUAGE NoImplicitPrelude     #-}
{-# LANGUAGE PartialTypeSignatures #-}
{-# LANGUAGE ViewPatterns          #-}
module Crypto.Hash.Types.Digest.Read where
import           Rebase.Prelude          hiding (hash)

import           Crypto.Hash
import           Data.ByteArray.Encoding
import qualified Rebase.Data.Text        as Text

instance HashAlgorithm a =>
         Read (Digest a) where
  readsPrec :: Int -> (String -> [(Digest a, String)])
  readsPrec _ (Text.encodeUtf8 . Text.pack -> bytes) =
    toList $ (flip (,) "") <$> (digestFromByteString =<< baseConv bytes)
    where
      baseConv :: ByteString -> Maybe (ByteString)
      baseConv = listToMaybe . toList . convertFromBase Base16