Nested filters

[amphineko]

Hello there,

I'm a newbie to BIRD, using BIRD 1.6.3 and setting up my first router.
I have multiple filters which filter different subnets and apply
different attribute modifications.

Currently I put my subnet checks in a function which returns true if a
subnet matches, and invoke the function in a filter like this:

function is_asxxxx() {
    if net ~ [114.51.4.0/24] then return true;
    return false;
}

function is_asyyyy() {
    if net ~ [19.19.81.0/24] then return true;
    return false;
}

filter f_customers {
    if is_asxxxx() then accept;
    if is_asyyyy() then {
        bgp_community.add((114514, 191981));
        accept;
    }
    reject;
}

I'm wondering if I can invoke other filters inside a filter, so the
is_asxxx can also used as an filter. I can't find an example to
achieve this.

Regards,
Naoki Kobayashi