namespace boost {
  namespace genetics {
    template<typename WordType, typename ParentType, typename IndexArrayType, 
             typename RleArrayType> 
      class basic_augmented_string;

    typedef basic_augmented_string< uint64_t, dna_string, std::vector< uint32_t >, std::vector< uint32_t > > augmented_string;
    typedef basic_augmented_string< uint64_t, mapped_dna_string, mapped_vector< uint32_t >, mapped_vector< uint32_t > > mapped_augmented_string;
    template<> 
      int get_code<augmented_string >(const augmented_string & str, 
                                      size_t index);
  }
}