svoid gazelle_dropMatchedDefaultRules(L<GazelleTree> l, O... _) {
  L<GazelleTree> defaults = [GazelleTree t : l | cic(t.ruleComments(), "default")];
  if (nempty(defaults) && l(defaults) < l(l)) {
    if (boolPar debug(_)) {
      print("Removing default rules:");
      printIndentLines(defaults);
      print("Because there are also:");
      printIndentLines(listMinusSet(l, defaults));
    }
    l.removeAll(defaults);
  }
}