PF Select specific IP addresses from interface

Hi there,

I'm writing the /etc/pf.conf rules for my machine with both IPv4 and IPv6. My public interface has two IPs (inet and inet6).

ifconfig output:
en0: flags=...
    ether xx:...:xx
    inet6 xx:ADDRESS_0:xx%en0 prefixlen 64 scopeid 0x1
    inet 00.ADDRESS_0.00 netmask ...
    inet6 xx:ADDRESS_1:xx prefixlen 64
    inet 00.ADDRESS_1.00 netmask ...
    status: active

Now, [FONT=Courier New]address 0[/FONT] is the public IPv4 and [FONT=Courier New]address 1[/FONT] is the public IPv6. There is a way to easily select only those addresses in pf.conf()?

Since this machine is provisioned in a cloud (Digital Ocean, for reference) I cannot change the interface settings and I'm trying to avoid to manually write the addresses in the rules.

I'm aware of using [FONT=Courier New]:0[/FONT], yet this select the "wrong" inet6 address. So far the best I can do is to use all of them with the following macro:

ext_if = "en0"
public_ip = "{" $ext_if "}"

That's working, yet is not optimal.

Thank you very much.