map_example

  auto map = [] (const auto &function, const auto &container )
  {
      auto retval = container;
      retval.clear();
      for (const auto &elem : container)
          retval.push_back(function(elem));
      return retval;
  };

  vector<int> data {1,2,3,4};
  vector<int> map_results = map(double_incr_decor,data);