(* File GRPRN.RF *)

(* Project: GR *)

fun print_set (s, tks) =
  let fun print_set_rest [] = ()
        | print_set_rest (s1::rest) =
            (output(s, s1);
             if null rest then ()
             else
              (output(s, " | "); print_set_rest rest))
      fun print_set_loop rest =
            case rest
              of s1::s2::s3::s4::s5::rest' =>
                   (output(s, s1); output(s, " | ");
                    output(s, s2); output(s, " | ");
                    output(s, s3); output(s, " | ");
                    output(s, s4); output(s, " | ");
                    output(s, s5);
                    if null rest' then ()
                    else
                      (output(s, " |\n  ");
                       print_set_loop rest'))
               | _ =>
                   print_set_rest rest
  in output(s, "("); print_set_loop tks; output(s, ")") end;

fun print_grammar (s, Grammar (tokens, rules)) =
  let fun print_rhs [] =
            output(s, "/* empty */")
        | print_rhs rhs =
            foreach
              (fn (N n) => (output(s, n); output(s, " "))
                | (T t) => (output(s, t); output(s, " ")))
              rhs
      fun print_rhss (p, []) =
            output(s, "        ;\n\n")
        | print_rhss (p, (Rhs rhs)::rest) =
            (output(s, "        "); output(s, p); output(s, "   ");
             print_rhs rhs; output(s, "\n"); print_rhss ("|", rest))
      fun print_rules (s, rules) =
            (foreach
               (fn Group (n, rhss) =>
                 (output(s, n); output(s, "\n"); print_rhss (":", rhss)))
               rules;
             output(s, "\n"))
  in output(s, "%token\n"); print_set(s, tokens);
     output(s, "\n%%\n\n"); print_rules(s, rules)
  end;