std::type_index를 사용하면 타입을 id로 사용한 container를 사용할 수 있습니다.

#include <iostream>
#include <unordered_map>
#include <type_traits>
#include <typeindex>
#include <functional>

using namespace std;

unordered_map<type_index, function<void()>> mapType;

template<typename T>
void WhatIsThis(T) {
	mapType[typeid(T)]();
}
int main() {
	mapType.emplace(typeid(int), []{cout << "this is int" << endl;});
	mapType.emplace(typeid(float), []{cout << "this is float" << endl;});
	mapType.emplace(typeid(double), []{cout << "this is double" << endl;});
	mapType.emplace(typeid(const char*), []{cout << "this is const char*" << endl;});
	
	WhatIsThis(1);
	WhatIsThis(0.5f);
	WhatIsThis(0.5);
	WhatIsThis("Hello world");
	return 0;
}