#include <iostream>

#include <map>
#include <string>

#include <boost/foreach.hpp>
#include <boost/range/adaptor/map.hpp>

using namespace std;
using namespace boost::adaptors;

typedef map<string, string> my_map_t;

my_map_t map_generator() {
  cout << "  Generating map" << endl;
  my_map_t return_value;
  return_value["igor!"] = "james";
  return_value["12345"] = "ABCDE";
  return_value["QWERT"] = "qwert";
  return return_value;
}

void using_temp_ref(const my_map_t &my_map)
{
  BOOST_FOREACH(const string &key, my_map | map_keys) {
    cout << "key = '" << key << "'" << endl;
  }
}

template <typename T>
void using_range_iterator(const boost::iterator_range<T> &keys_range)
{
  BOOST_FOREACH(const string &key, keys_range) {
    cout << "key = '" << key << "'" << endl;
  }
}


int main(int argc, char** argv) {
    cout << "Test #1 (local variable)" << endl;
    my_map_t m = map_generator();
    BOOST_FOREACH(const string &key, m | map_keys) {
      cout << "key = '" << key << "'" << endl;
    }

    cout << "Test #2 (value_type)" << endl;
    BOOST_FOREACH(const my_map_t::value_type& p, map_generator()) {
      cout << "key = '" << p.first << "'" << endl;
    }

    cout << "Test #3 (temp ref)" << endl;
    using_temp_ref(map_generator());

    cout << "Test #4 (range_iterator)" << endl;
    using_range_iterator(map_generator() | map_keys);

    cout << "Test #5 (bug)" << endl;
    BOOST_FOREACH(const string &key, map_generator() | map_keys) {
      cout << "key = '" << key << "'" << endl;
    }

    cout << "Test passed!" << endl;
}