associative std::tuple container

Is it possible to define (in a simple way, possibly re-using std container) an "associative std::tuple", or said in other words a "variadiac std::map".

Something like this (this interface is just to explain, other possible interfaces are welcome):

AssociativeTuple<std::string> at;  // std:string is the key type
at.insert<float>("my_float", 3.14);
at.insert<int>("my_int", 42);
at.insert<std::string>("my_string", "hello world!");

assert(get(at, "my_float") == 3.14);
assert(get(at, "my_int") == 42);
assert(at["my_string"] == "hello world!");

assert(std::is_same<at.type_of("my_float")::type, float>)

for (auto it : at) { std::cout << it.first << " = " << it.second; }

Other desirable constraints:

• The key and the values (and also their type) are known at run time


• Access performance, get should be fast


• The user don't have to remember the type associated to a key

My real problem is just with value of float/int type (and what I am doing is to store in everything in a std::map<std::string, float> and converting to int when necessary), but a general solution is desirable. In my real case the keys are always std::string.