tagXRef :: Records -> Maybe (ByteString, ByteString) 
tagXRef (Fix (TreeF (U (Record t (X (XRef x)))) _)) = Just (t,x)
tagXRef :: Records -> Maybe (ByteString, ByteString)
tagXRef (Fix (TreeF (U (Record t (X (XRef x)))) _)) = Just (t,x)
tagXRef (Fix (TreeF (U (Record t (X (XRef x)))) _)) = Just (t,x)