How to: Create Umbrella Type

[SixTsevN]

Hey there,
I was wondering if you know way to create an "umbrella" type/class/struct of existing c++ types or windows types.

Let me explain.
I want to address ~3 different structs with a single pointer and downcast but, they are not a part of the same hierarchy.

Is there a way that I could for example's sake, include a POINT and a RECT under some "umbrella" type so I can go like this:

// Working Variables
//---------------------------------------------------------
Umbrella* pUmbType1(NULL);
Umbrella* pUmbType2(NULL);
POINT     ptExamp = { 0 };
RECT      egRect  = { 0, 0, 0, 0 };

// Typecast POINT and RECT to umbrella pointer
//---------------------------------------------------------
pUmbType1 = (Umbrella*)ptExamp;
pUmbType2 = (Umbrella*)egRect;

I want to do this, so I don't have to duplicate code for each type.

[JLBorges]

If the types under the umbrella form a closed set: http://www.boost.org/doc/libs/1_57_0/doc/html/variant.html

Otherwise: http://www.boost.org/doc/libs/1_57_0/doc/html/any.html

[SixTsevN]

Thank you very much.

[SixTsevN]

ugh...

boost::any doesn't have any pointer or reference typecasts -_-;;

[JLBorges]

Wrap references.

#include <iostream>
#include <boost/any.hpp>
#include <functional>

int main()
{
    int i = 7 ;
    double d = 56.7 ;
    boost::any many[] { std::ref(i), &d } ;

    int& r = boost::any_cast< std::reference_wrapper<int> >( many[0] ) ;
    int* pi = &r ;
    r = 789 ;
    *pi += 32 ;
    std::cout << i << '\n' ;

    double* p = boost::any_cast<double*>( many[1] ) ;
    *p = 0.1 ;
    std::cout << d << '\n' ;
}

http://coliru.stacked-crooked.com/a/fd4709564e41871a