type_map.cpp

#include <typeinfo>
#include <map>

struct A{};
struct B{};

struct type_info_cmp{
    bool operator ()(const std::type_info *lhs, const std::type_info *rhs) const{
        return lhs->before(*rhs) != 0;
    }
};

int main(){
    A a;
    B b;
    std::map<const std::type_info*, std::string, type_info_cmp> map;
    map[&typeid(a)] = "A";
    map[&typeid(b)] = "B";

    return 0;
}