Fix issue with dynamic codegen of first.aps - Alternative approach

[amir734jj]

Alternative approach to #154

Final output

  def c_item_first(anode : T_Item) : T_SymbolLattice = {
    var collection : T_SymbolLattice = t_SymbolLattice.v_none();
    for (anchor <- t_Result.t_Item.nodes) anchor match {
      case p_terminal(v_self,v_s) => {
        if (anode eq v_self) collection = t_SymbolLattice.v_combine(collection,t_SymbolLattice.v_single(v_s));
      }
      case _ => {}
    }
    for (anchor <- t_Result.t_Item.nodes) anchor match {
      case p_nonterminal(v_self,v_s) => {
        t_DeclarationTable.v_select(v_firstTable,v_s) match {
          case t_DeclarationTable.p_table_entry(_,v_0,v_item_first_objs) => {
            if (anode eq v_self) collection = t_SymbolLattice.v_combine(collection,v_item_first_objs);
          }
          case _ => {
          }
        }
      }
      case _ => {}
    }
    return collection;
  }