--- Return true if the first argument (a CIDR range) contains the
--- second (another CIDR range). There are a lot of ways we can be fed
--- junk here. For lack of a better alternative, just return False when
--- we are given nonsense.
-contains :: Cidr -> Cidr -> Bool
-contains Cidr.None _ = False
-contains _ Cidr.None = False
-contains (Cidr _ Maskbits.None) _ = False
-contains (Cidr IPv4Address.None _) _ = False
-contains _ (Cidr _ Maskbits.None) = False
-contains _ (Cidr IPv4Address.None _) = False
-
--- If the number of bits in the network part of the first address is
--- larger than the number of bits in the second, there is no way that
--- the first range can contain the second. For, if the number of
--- network bits is larger, then the number of host bits must be
--- smaller, and if cidr1 has fewer hosts than cidr2, cidr1 most
--- certainly does not contain cidr2.
+-- | Return true if the first argument (a CIDR range) contains the
+-- second (another CIDR range). There are a lot of ways we can be
+-- fed junk here. For lack of a better alternative, just return
+-- False when we are given nonsense.