I am new user of Boost, I tried to use boost::variant first, but in comparison to boost::any performance of boost::variant appears to be around 4 times slower, so settled for boost::any. Also boost::any has cleaner interface but I don't know how to query current type information for boost::any ? My code looks like following map<unsigned int, boost::any> result_table; result_table[1] = 543.434; vector<int> vec; .. Some vec population code; result_table[2] = vec; Now I need to develop a stringify function for result_table; I can fetch the results back as boost::any value = result_table[2]; But I need to know the type of value, so that I can treat it accordingly to stringify; I know there exists type_traits, but very limited examples of type_traits is provided on Boost documentation and particularly, I am clueless about how to use type_traits in above context to find out what is the current type returned by result_table[int] Also I want to know if Boost has any Hash map implementation that can be superior in performance compare to regular std::map ?? Thanks, Piyush