I would like to use raku’s comb function with a regex from a grammar instead of a stand alone regex. For example in the following code, which parses journalctl logs from stdin, I would like to replace the &h in MAIN with something like &Journalctl::full_log

role Log {
  token preamble { ... };
  token message { [^<preamble>]* };
  regex full_log { <preamble> <message> };
}

grammar Journalctl does Log {
  token date { S+sdd:dd:dd };
  token hostname { [^s]+ };
  token ctl_unit { [^[]+ };
  token pid { d+ };
  regex preamble { <date> 's' <hostname> <ctrl_unit> '[' <pid> ']' ':' }
}

sub MAIN( ) {
  my regex h { h. };
  for $*IN.comb(&h) -> $wof {  # FIXME
    say $wof;
  }
}

Here are some example journalctl logs for reference:

Jun 25 14:45:54 cpu-hostname systemd-timesyncd[725]: Initial synchronization to time server 185.125.190.56:123 (ntp.ubuntu.com).
Jun 25 14:45:54 cpu-hostname systemd-resolved[722]: Clock change detected. Flushing caches.