unseal :: (Monad cx) => String -> V cx -> cx (V cx)
unseal s (P (S (':':s') v) e) | (s == s') = return (P v e)
unseal :: (Monad cx) => String -> V cx -> cx (V cx)
unseal s (P (S (':':s') v) e) | (s == s') = return (P v e)
unseal s (P (S (':':s') v) e) | (s == s') = return (P v e)