Question

I need to store the type of an object in a class.
This would look like:

template<class T>
class box
{
private:

    type_info type;
    T data;
}

The reason why I need to store the type information is complex to explain, anyway I would know if this is possibile in C++.
When i try to compile an instruction like:

type=typeid(data);

I get a syntax error:
No matching for initialization of ‘std::type_info’
So it seems like type_info hasn’t the constructor with no arguments.Is possibile then in some way, to memorize the type of an object into a data?

Answer 1

typeinfo is noncopyable – its constructors and assignment operator are private (in C++11 they are flagged deleted). you’re probably after something along these lines:

template<class T>
class box
{
public:
    box() : data(), type(typeid(data))
    {
    }
private:
    T data;
    const type_info& type;
};