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module Erebos.UUID (
UUID,
toString, fromString,
toText, fromText,
toASCIIBytes, fromASCIIBytes,
nextRandom,
) where
import Crypto.Random.Entropy
import Data.Bits
import Data.ByteString qualified as BS
import Data.ByteString.Lazy qualified as BSL
import Data.Maybe
import Data.UUID.Types
nextRandom :: IO UUID
nextRandom = do
[ b0, b1, b2, b3, b4, b5, b6, b7, b8, b9, ba, bb, bc, bd, be, bf ]
<- BS.unpack <$> getEntropy 16
let version = 4
b6' = b6 .&. 0x0f .|. (version `shiftL` 4)
b8' = b8 .&. 0x3f .|. 0x80
return $ fromJust $ fromByteString $ BSL.pack [ b0, b1, b2, b3, b4, b5, b6', b7, b8', b9, ba, bb, bc, bd, be, bf ]
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