{IPv4(127, 0, 0, 1), true, false},
	{IPv4(240, 0, 0, 1), true, false},
	{IPv6unspecified, false, true},
	{IPv6loopback, false, true},
	{IPv6interfacelocalallnodes, false, true},
	{IPv6linklocalallnodes, false, true},
	{IPv6linklocalallrouters, false, true},
	{ParseIP("ff05::a:b:c:d"), false, true},
	{ParseIP("fe80::1:2:3:4"), false, true},
	{ParseIP("2001:db8::123:12:1"), false, true},
}

pkg net/netip, func AddrFrom4([4]uint8) Addr
pkg net/netip, func AddrFromSlice([]uint8) (Addr, bool)
pkg net/netip, func AddrPortFrom(Addr, uint16) AddrPort
pkg net/netip, func IPv4Unspecified() Addr
pkg net/netip, func IPv6LinkLocalAllNodes() Addr
pkg net/netip, func IPv6Unspecified() Addr
pkg net/netip, func MustParseAddr(string) Addr
pkg net/netip, func MustParseAddrPort(string) AddrPort
pkg net/netip, func MustParsePrefix(string) Prefix

	IPv6loopback               = IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}
	IPv6interfacelocalallnodes = IP{0xff, 0x01, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x01}
	IPv6linklocalallnodes      = IP{0xff, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x01}
	IPv6linklocalallrouters    = IP{0xff, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x02}
)

// See the Addr type's field docs.
var (
	z0    unique.Handle[addrDetail]
	z4    = unique.Make(addrDetail{})
	z6noz = unique.Make(addrDetail{IsV6: true})
)

// IPv6LinkLocalAllNodes returns the IPv6 link-local all nodes multicast
// address ff02::1.
func IPv6LinkLocalAllNodes() Addr { return AddrFrom16([16]byte{0: 0xff, 1: 0x02, 15: 0x01}) }

// IPv6LinkLocalAllRouters returns the IPv6 link-local all routers multicast
// address ff02::2.