typedef tr1::unordered_map hashmap;
typedef map hashmap;

map<string, string>
map<string, int>
map <string, map<string,int>> ..etc

template <typename Key, typename T>
struct hashmap {
    typedef std::unordered_map<Key, T> type;
    // or
    //typedef std::map<Key, T> type;
};

hashmap<int, float>::type some_map;

template <typename T1, typename T2>
struct hashmap
{
    typedef std::map<T1, T2> type;
};

#ifdef HAVE_TR1
#include <tr1/unordered_map>
#define HASH_MAP std::tr1::unordered_map
#else
#include <map>
#define HASH_MAP std::map
#endif