// Check that the first class of the Cd_graph is a construction class
*operation* int check_first_class()
  *init* (@ 1 @)

  *traverse* *from*    Cd_graph
             *to-stop* Adjacency_Nlist

  *wrapper* Cd_graph
    *prefix* (@ cout << endl
                     << "Checking that the first production is an" << endl
                     << "\tunparameterized construction production ..."
                     << endl;
              @)

  *wrapper* Adjacency_Nlist
    *prefix* (@ Adjacency_list_iterator next_Adjacency(*this);
                if (!next_Adjacency()->check_first_class1())
                  return_val = 0;
              @)

// If a repetition or alternation class can be reached from this adjacency
// class then the first class is not a construction class.
*operation* int check_first_class1()
  *init* (@ 1 @)

  *traverse* *from*      Adjacency
             *to-stop*   {Repetit_n, Alternat_ns}

  *wrapper* {Repetit_n, Alternat_ns}
    *prefix* (@ return_val = 0; 
              @)
  
  *wrapper* Adjacency
    *suffix* (@ if (this->get_parameters() != NULL) return_val = 0;
                if (return_val == 0) {
                  cout << endl 
                       << "The first production of your class dictionary has to"
                       << endl
                       << "be an unparameterized production. Your first production"
                       << endl;
                  this->g_print();
                  cout << "  is not an unparameterized construction production."
                       << endl
                       << "Add for example" << endl
                       << "\t\tExample = <example> ";
                  this->get_source()->g_print();
                  if (this->get_parameters() != NULL) {
                    cout << "(";
                    this->get_parameters()->g_print();
                    cout << ")";
                  }
                  cout << " ." << endl << "as your first production." << endl;
                }
              @)