fair enough, however the intention is to show how one could create rules on Sparrow/Raku, not to show rules ... Maybe I should have mentioned that ...

for example this is more interesting example evaluation of net.ipv4.tcp_synack_retries"

regexp: ^^ "net.ipv4.tcp_synack_retries" \s* "=" \s* (\d+) \s* $$

generator: <<RAKU
!raku
if matched().elems {
  my $v = capture()[];
  say "note: net.ipv4.tcp_synack_retries={$v}";
  if $v >= 3 && $v <= 5 {
     say "assert: 1 net.ipv4.tcp_synack_retries in [3..5] range"
  } else {
     say "assert: 0 net.ipv4.tcp_synack_retries in [3..5] range"
  }
} else {
  say "note: net.ipv4.tcp_synack_retries setting not found"
}
RAKU