text: #include "doc_list_index.hpp"
  #include <iostream>
  #include <fstream>
  
  using namespace std;
  using namespace sdsl;
  
  using idx_type = IDX_TYPE;
  
  int main(int argc, char* argv[])
  {
      if (argc < 2) {
          cout << "Usage: " << argv[0] << " index_file [html_file]" << endl;
          return 1;
      }
      string index_file = string(argv[1]);
      idx_type idx;
  
      if (!load_from_file(idx, index_file)) {
          std::cerr << "Could not load index file" << std::endl;
          return 1;
      }
      if (argc > 2) {
          ofstream out(argv[2]);
          write_structure<HTML_FORMAT>(idx, out);
      } else {
          cout<<"# index_file = "<<index_file<<endl;
          cout << "# size = " << size_in_bytes(idx) << endl;
      }
  }
  