*operation* void bind_pde(Meta_def * finalmeta,Propagation_directive_exp *& pdexp)
  *traverse*
     *from* Propagation_directive_exp *to-stop* {Pde, Dir_name_with_exp}
  *wrapper* Dir_name_with_exp
    *prefix*
    (@
       finalmeta->bind_pde2(this->get_inst(),pdexp);
    @)
  *wrapper* Merge_pde
    *prefix*
    (@
       Propagation_directive_exp * exp1 = NULL;
       Propagation_directive_exp * exp2 = NULL;
       this->get_pde1()->bind_pde(finalmeta,exp1);
       this->get_pde2()->bind_pde(finalmeta,exp2);
       if (exp1 != NULL)
         this->rset_pde1((Propagation_directive_exp *)exp1->g_copy())->g_delete();
       if (exp2 != NULL)
         this->rset_pde2((Propagation_directive_exp *)exp2->g_copy())->g_delete();
    @)
  *wrapper* Join_pde
    *prefix*
    (@
       Propagation_directive_exp * exp1 = NULL;
       Propagation_directive_exp * exp2 = NULL;
       this->get_pde1()->bind_pde(finalmeta,exp1);
       this->get_pde2()->bind_pde(finalmeta,exp2);
       if (exp1 != NULL)
         this->rset_pde1((Propagation_directive_exp *)exp1->g_copy())->g_delete();
       if (exp2 != NULL)
         this->rset_pde2((Propagation_directive_exp *)exp2->g_copy())->g_delete();
    @)

*operation* void bind_pde2(DemIdent *inst_name, Propagation_directive_exp *& pdexp)
  *traverse*
    *from* Meta_def *to* Meta_macro_def
  *wrapper* Meta_macro_def
    *prefix*
    (@
       Propagation_directive_exp * r = NULL;

       if (this->get_dirs() != NULL)
         this->get_dirs()->find_pde(r,inst_name);
      
       if (r != NULL)
         pdexp = (Propagation_directive_exp *)r->g_copy();
       else
         {
           cout << toolname << ": undefined propagation directive expression variable : '"
                << inst_name->get_val() << "' on line " << inst_name->get_line_number() << endl;
           exit(-1);
         }
    @)