*operation* void check_meta()
  *traverse*
    *from* Meta_def *to* Meta_macro_def
*wrapper* Meta_macro_def
*prefix*
(@
    ///////////////////////////////////////////////////////////////////////////
    // there is no need to check class and relation variables
    // the algorithm goes like this:
    //    first : find all the meta variables which contain no use
    //            of meta variables
    //    second: substitute with the variables found above
    //            if there is no progress and there is still more than one
    //            left, it is an error.
    ////////////////////////////////////////////////////////////////////////////

    static Meta_macro_def * final_madef = new Meta_macro_def();
    static Meta_def * final_meta = new Meta_def();
    final_meta->set_meta_def(final_madef);

    if ((this->get_class_sets() == NULL) && (this->get_dirs() == NULL))
       return;

    Class_set_def_Amplist * final_csets = NULL;
    Dir_meta_def_Amplist  * final_dirs  = NULL;

    if (this->get_class_sets() != NULL)
       final_csets = new Class_set_def_Amplist();

    if (this->get_dirs() != NULL)
       final_dirs = new Dir_meta_def_Amplist();

    final_madef->set_class_sets(final_csets);
    final_madef->set_dirs(final_dirs);

    int progress = 0;

    while (1)
    {
        progress = 0;
        if (this->get_class_sets() != NULL)
        {
           Class_set_def_Amplist * t = new Class_set_def_Amplist();
           Class_set_def_list_iterator next(*this->get_class_sets());
           Class_set_def * each;
           while (each = next())
           {
              int c = 0;
              each->no_meta_vars_in_cset(c);
              if (!c)
              {
                 final_csets->append(each);
                 progress = 1;
              } else
                t->append(each);
           }
           if (t->list_length() == 0)
           {
             delete t;
             t = NULL;
           }
           delete this->rset_class_sets(t);
        }

        if (this->get_dirs() != NULL)
        {
           Dir_meta_def_Amplist * t = new Dir_meta_def_Amplist();
           Dir_meta_def_list_iterator next(*this->get_dirs());
           Dir_meta_def * each;
           while (each = next())
           {
              int c = 0;
              each->no_meta_vars_in_dir(c);
              if (!c)
              {
                 final_dirs->append(each);
                 progress = 1;
              } else
                 t->append(each);
           }
           if (t->list_length() == 0)
           {
               delete t;
               t = NULL;
           }
           delete this->rset_dirs(t);
        }  

      /////////////////////////////////////////////////////////////////
      // try to reduce meta variables
      /////////////////////////////////////////////////////////////////
      if (this->get_class_sets() != NULL)
      {
         this->get_class_sets()->check_meta_csets(final_meta);
         this->get_class_sets()->check_meta_cdirs(final_meta);
      }
      if (this->get_dirs() != NULL)
      {
         this->get_dirs()->check_meta_dsets(final_meta);
         this->get_dirs()->check_meta_ddirs(final_meta);
      }
      if (progress == 0)
         break;
    }

    if ((this->get_class_sets() == NULL) && (this->get_dirs() == NULL))
    {
       this->set_class_sets(final_csets);
       this->set_dirs(final_dirs);
       return;
    }

    cout << toolname
         << ": illegal meta definitions : there is no way to futher reduce the meta definitions.\n"
         << " there may be some undefined meta variables or recursive definitions." << endl;

    if (this->get_class_sets() != NULL)
    {
       cout << "*class-set*" << endl;
       this->get_class_sets()->g_print(cout);
       cout << endl;
    }
    if (this->get_dirs() != NULL)
    {
       cout << "*dir*" << endl;
       this->get_dirs()->g_print(cout);
       cout << endl;
    }
    exit(-1);
@)

*operation* void check_meta_csets(Meta_def * finalmeta)
  *traverse*
    *from* Class_set_def_Amplist *to* Class_set_def
*wrapper* Class_set_def
*prefix*
(@
    Vertex_selector * reduced = NULL;
    this->get_class_set()->check_meta_sets(finalmeta,reduced);
    if (reduced)
       this->rset_class_set((Vertex_selector*)reduced->g_copy())->g_delete();
@)

*operation* void check_meta_dsets(Meta_def * finalmeta)
  *traverse*
    *from* Dir_meta_def_Amplist *to* Dir_meta_def
*wrapper* Dir_meta_def
*prefix*
(@
    Vertex_selector * reduced = NULL;
    this->get_pde()->check_meta_sets(finalmeta,reduced);
@)

*operation* void check_meta_sets(Meta_def * finalmeta,Vertex_selector *& reduced)
  *traverse*
    *from* {Class_set_def, Propagation_directive_exp, Require_vertex_selector, Require_meta_edges}
    *to*   {Vertex_set_comp, Class_set_name, Late_selected_terms}
*wrapper* Class_set_name
*prefix*
(@
    DemIdent * n = this->get_name();
    Vertex_selector * r = NULL;
    if ( finalmeta->get_meta_def()->get_class_sets())
         finalmeta->get_meta_def()->get_class_sets()->find_set(r,n);
    if (r != NULL)
       reduced = (Vertex_selector *)r->g_copy();
@)
*wrapper* Vertex_set_comp
*prefix*
(@
    Vertex_selector * reduced_arg1 = NULL;
    this->get_arg1()->check_meta_sets(finalmeta,reduced_arg1);
    if (reduced_arg1)
       this->rset_arg1((Vertex_set*)reduced_arg1->g_copy())->g_delete();

    Vertex_selector * reduced_arg2 = NULL;
    this->get_arg2()->check_meta_sets(finalmeta,reduced_arg2);
    if (reduced_arg2)
       this->rset_arg1((Vertex_set*)reduced_arg2->g_copy())->g_delete();
    reduced = NULL;
@)

*wrapper* Require_vertex_selector
*suffix*
(@
   Vertex_selector * r = NULL;
   this->get_vertices()->check_meta_sets(finalmeta,r);
   if (r)
     this->rset_vertices((Vertex_selector*)r->g_copy())->g_delete();
   reduced = NULL;
@)


*wrapper* Pde
*suffix*
(@
    Vertex_selector * r = NULL;
    this->get_source_port()->check_meta_sets(finalmeta,r);
    if (r)
       this->rset_source_port((Vertex_selector*)r->g_copy())->g_delete();
   reduced = NULL;
@)


*wrapper* Targets
*suffix*
(@
    Vertex_selector * r = NULL;
    this->get_targets()->check_meta_sets(finalmeta,r);
    if (r)
       this->rset_targets((Vertex_selector*)r->g_copy())->g_delete();
   reduced = NULL;
@)

*wrapper* Require_meta_edges
*suffix*
(@
    Vertex_selector * r = NULL;
    this->get_vertices()->check_meta_sets(finalmeta,r);
    if (r)
       this->rset_vertices((Vertex_selector*)r->g_copy())->g_delete();
   reduced = NULL;
@)


*wrapper* Meta_construction_edge
*suffix*
(@
    Vertex_selector * reduced_from = NULL;
    this->get_from()->check_meta_sets(finalmeta,reduced_from);
    if (reduced_from)
       this->rset_from((Vertex_selector*)reduced_from->g_copy())->g_delete();

    Vertex_selector * reduced_to = NULL;
    this->get_to()->check_meta_sets(finalmeta,reduced_to);
    if (reduced_to)
       this->rset_to((Vertex_selector*)reduced_to->g_copy())->g_delete();
@)


*wrapper* Meta_alternation_edge
*suffix*
(@
    Vertex_selector * reduced_from = NULL;
    this->get_from()->check_meta_sets(finalmeta,reduced_from);
    if (reduced_from)
       this->rset_from((Vertex_selector*)reduced_from->g_copy())->g_delete();

    Vertex_selector * reduced_to = NULL;
    this->get_to()->check_meta_sets(finalmeta,reduced_to);
    if (reduced_to)
       this->rset_to((Vertex_selector*)reduced_to->g_copy())->g_delete();
@)


*wrapper* Meta_inheritance_edge
*suffix*
(@
    Vertex_selector * reduced_from = NULL;
    this->get_from()->check_meta_sets(finalmeta,reduced_from);
    if (reduced_from)
       this->rset_from((Vertex_selector*)reduced_from->g_copy())->g_delete();

    Vertex_selector * reduced_to = NULL;
    this->get_to()->check_meta_sets(finalmeta,reduced_to);
    if (reduced_to)
       this->rset_to((Vertex_selector*)reduced_to->g_copy())->g_delete();
@)

*wrapper* Meta_repetition_edge
*suffix*
(@
    Vertex_selector * reduced_from = NULL;
    this->get_from()->check_meta_sets(finalmeta,reduced_from);
    if (reduced_from)
       this->rset_from((Vertex_selector*)reduced_from->g_copy())->g_delete();

    Vertex_selector * reduced_to = NULL;
    this->get_to()->check_meta_sets(finalmeta,reduced_to);
    if (reduced_to)
       this->rset_to((Vertex_selector*)reduced_to->g_copy())->g_delete();
@)


*operation* void check_meta_ddirs(Meta_def * finalmeta)
   *traverse*
      *from* Dir_meta_def_Amplist *to* Dir_meta_def
*wrapper* Dir_meta_def
*suffix*
(@
    Propagation_directive_exp * pdexp = NULL;
    this->get_pde()->bind_pde(finalmeta,pdexp);
    if (pdexp != NULL)
      this->rset_pde((Propagation_directive_exp *)pdexp->g_copy())->g_delete();
@)

*operation* void check_meta_cdirs(Meta_def * finalmeta)
   *traverse*
      *from* Class_set_def_Amplist *to*   Late_selected_terms
*wrapper* Late_selected_terms
*suffix*
(@
    Propagation_directive_exp * pdexp = NULL;
    this->get_pde()->bind_pde(finalmeta,pdexp);
    if (pdexp != NULL)
      this->rset_pde((Propagation_directive_exp *)pdexp->g_copy())->g_delete();
@)