Functions with 2+ arguments

[Ondrej Zajicek]

On Tue, Oct 22, 2024 at 09:34:59PM +0200, Pim van Pelt via Bird-users wrote:
> Hoi folks,
> 
> Consider the following two functions in Bird v2.15.1:
> 
> function test_ok(int var1) -> bool
> {
>   if (bgp_large_community ~ [ (50869,1000,var1), (50869,2000,8298) ]) then
> return true;
>   return false;
> }
> 
> function test_nok(int var1; int var2) -> bool
> {
>   if (bgp_large_community ~ [ (50869,1000,var1), (50869,2000,var2*)* ]) then
> return true;
>   return false;
> }
> 
> The first one parses fine, but the second function yields a parse error on
> bird: __filename__:199:66 Expression of type int expected

Hi

Not sure why you get the parse error, when i tried that, function
test_nok() got parsed just fine.

The bigger issue is that neither test_ok() nor test_nok() should parse,
as sets are required to be constants, so only contant expressions
(including constants defined by 'define') should be allowed in them, not
local variables.

The error is properly generated in case of:

function test_nok(int var1; int var2) -> bool
{
        if (bgp_local_pref ~ [ var1, var2 ]) then
                return true;
}

Parse error filter/test.conf, line 1903: Constant name required

But not in more complex expressions like:

function test_nok(int var1; int var2) -> bool
{
        if (bgp_local_pref ~ [ (var1 + 1), (var2 + 1) ]) then
                return true;
}

(or the large community constructor like in your case.)


Just use:

{
	if ((50869,1000,var1) ~ bgp_large_community) ||
	   ((50869,2000,var2) ~ bgp_large_community)
	then return true;
}

-- 
Elen sila lumenn' omentielvo

Ondrej 'Santiago' Zajicek (email: santiago at crfreenet.org)
"To err is human -- to blame it on a computer is even more so."