update :: (ByteArrayAccess message, HashAlgorithm a)
       => Context a  -- ^ Current HMAC context
       -> message    -- ^ Message to append to the MAC
       -> Context a  -- ^ Updated HMAC context
update (Context octx ictx) msg =
    Context octx (hashUpdate ictx msg)
update :: (ByteArrayAccess message, HashAlgorithm a)
       => Context a  -- ^ Current HMAC context
       -> message    -- ^ Message to append to the MAC
       -> Context a
update (Context octx ictx) msg =
    Context octx (hashUpdate ictx msg)
update (Context octx ictx) msg =
    Context octx (hashUpdate ictx msg)