Свой TypeInfo и регистрация типов

#include <iostream>
#include <string>
#include <functional>
//------------------------------------------------------------------------------
template<typename T>
class TypeInfo
{
    public:
       static const std::string typeName;
       
       using  FromStringFunction= T(*)(const std::string&);
       static const FromStringFunction fromString;
};
//------------------------------------------------------------------------------
#define TI_REGISTER_TYPE(TYPE,TYPE_NAME,FROM_STRING) \
    template<> const std::string TypeInfo<TYPE>::typeName= TYPE_NAME; \
    template<> const TypeInfo<TYPE>::FromStringFunction TypeInfo<TYPE>::fromString= FROM_STRING;
//------------------------------------------------------------------------------
TI_REGISTER_TYPE(int,"int",  [](auto s){ return std::stoi(s); } )
TI_REGISTER_TYPE(std::string, "string", [](auto s){ return s; } )
TI_REGISTER_TYPE(float,"float", [](auto s){ return std::stof(s); } )
//------------------------------------------------------------------------------
#undef TI_REGISTER_TYPE
//------------------------------------------------------------------------------
 
 
int main()
{
    std::cout << TypeInfo<int>().typeName << std::endl;
    std::cout << TypeInfo<std::string>().fromString("123") << std::endl;
    std::cout << TypeInfo<float>().fromString("12.3") << std::endl;
    
    /* Хочеться  иметь следующее: */
    // std::cout << std::boolalpha << TypeInfo<long long>().isRegistred  << std::endl;
 
    return 0;
}

template<typename T>
class Test
{
       static_assert(!TypeInfo<T>().isRegistred,"Недопустимый тип!");
      
      // ...
};

template<typename T>
struct TypeInfo: std::false_type {};
 
#define TI_REGISTER_TYPE(type, from_string_func) \
    template <> struct TypeInfo<type>: std::true_type { \
        template <typename T> type fromString(T &&s) {return (from_string_func)(std::forward<T>(s));} \
        const char * const m_name = #type; \
    }
 
//------------------------------------------------------------------------------
TI_REGISTER_TYPE(int, std::stoi);
TI_REGISTER_TYPE(std::string, [](auto s){ return s; } );
TI_REGISTER_TYPE(float, std::stof);

template <typename T> type fromString(T &&s) 
{
     return (from_string_func)(std::forward<T>(s));
}