// Per RFC 6724 Section 2.2:
//
//   We define the common prefix length CommonPrefixLen(S, D) of a
//   source address S and a destination address D as the length of the
//   longest prefix (looking at the most significant, or leftmost, bits)
//   that the two addresses have in common, up to the length of S's
//   prefix (i.e., the portion of the address not including the
//   interface ID).  For example, CommonPrefixLen(fe80::1, fe80::2) is
//   64.
Per RFC 6724 Section 2.2:
We define the common prefix length CommonPrefixLen(S, D) of a
source address S and a destination address D as the length of the
longest prefix (looking at the most significant, or leftmost, bits)
that the two addresses have in common, up to the length of S's
prefix .
Per RFC 6724 Section 2 . 2 : We define the common prefix length CommonPrefixLen ( S D ) of a source address S and a destination address D as the length of the longest prefix ( looking at the most significant or leftmost bits ) that the two addresses have in common up to the length of S ' s prefix .
fn common_prefix_len<Instant>(
            src: &AddressEntry<Ipv6Addr, Instant, UnicastAddr<Ipv6Addr>>,
            dst: SpecifiedAddr<Ipv6Addr>,
        ) -> u8 {
            core::cmp::min(
                src.addr_sub().addr().common_prefix_len(&dst),
                src.addr_sub().subnet().prefix(),
            )
        }
fn common_prefix_len < Instant > ( src : & AddressEntry < Ipv6Addr , Instant , UnicastAddr < Ipv6Addr > > , dst : SpecifiedAddr < Ipv6Addr > , ) -> u8 { core :: cmp :: min ( src . addr_sub ( ) . addr ( ) . common_prefix_len ( & dst ) , src . addr_sub ( ) . subnet ( ) . prefix ( ) , ) }
Per RFC 6724 Section 2.2:
We define the common prefix length CommonPrefixLen(S, D) of a
source address S and a destination address D as the length of the
longest prefix (looking at the most significant, or leftmost, bits)
that the two addresses have in common, up to the length of S's
prefix (i.e., the portion of the address not including the
interface ID).
Per RFC 6724 Section 2 . 2 : We define the common prefix length CommonPrefixLen ( S D ) of a source address S and a destination address D as the length of the longest prefix ( looking at the most significant or leftmost bits ) that the two addresses have in common up to the length of S ' s prefix ( i . e . the portion of the address not including the interface ID ) .
src
&AddressEntry<Ipv6Addr, Instant, UnicastAddr<Ipv6Addr>>
dst
SpecifiedAddr<Ipv6Addr>