private static boolean unqualified_reference_expression_4_0(PsiBuilder b, int l) {
    if (!recursion_guard_(b, l, "unqualified_reference_expression_4_0")) return false;
    boolean r;
    r = string_literal_tokens(b, l + 1);
    if (!r) r = regex_literal(b, l + 1);
    return r;
  }
private static boolean unqualified_reference_expression_4_0(PsiBuilder b, int l)