mirror/example/meta_prog_08.cpp

This example shows the usage of the meta-programming utilities and the intrinsic meta-functions for various meta-objects

Copyright 2008-2011 Matus Chochlik. Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

#include <mirror/mirror.hpp>
#include <type_traits>
#include <iostream>
#include "./classes.hpp"

MIRROR_NAMESPACE_BEGIN

// Helper functor class used by for_each_ii in print_virtual_bases_of
struct name_printer
{
    template <typename IterInfo>
    void operator()(IterInfo) const
    {
        typedef typename IterInfo::type MetaInheritance;
        // print the full name of the current base class
        std::cout << MetaInheritance::base_class::full_name();
        // if this is the last element in the traversal
        // then print the final dot or print a separating comma
        // otherwise
        if(IterInfo::is_last::value)
            std::cout << ".";
        else    std::cout << ", ";
    }
};

template <typename MetaClass>
void print_virtual_bases_of(void)
{
    using namespace mirror;
    std::cout << "Virtual base classes of the '"
        << MetaClass::full_name()
        << "' class: ";
    mp::for_each_ii<
        mp::only_if<
            base_classes<MetaClass>,
            std::is_same<
                inheritance_type<
                    mp::arg<1>
                >,
                spec_virtual_tag
            >
        >
    >(name_printer());
    std::cout << std::endl;
}


MIRROR_NAMESPACE_END


int main(void)
{
    using namespace mirror;
    print_virtual_bases_of<
        reflected<test::A>::type
    >();
    print_virtual_bases_of<
        reflected<test::B>::type
    >();
    print_virtual_bases_of<
        reflected<test::C>::type
    >();
    print_virtual_bases_of<
        reflected<test::D>::type
    >();
    print_virtual_bases_of<
        reflected<test::E>::type
    >();
    print_virtual_bases_of<
        reflected<test::F>::type
    >();
    print_virtual_bases_of<
        reflected<test::G>::type
    >();
    print_virtual_bases_of<
        reflected<test::H>::type
    >();
    //
    return 0;
}

/* Example of output:
Virtual base classes of the 'test::A' class:
Virtual base classes of the 'test::B' class:
Virtual base classes of the 'test::C' class: test::A, test::B.
Virtual base classes of the 'test::D' class: test::A, test::B.
Virtual base classes of the 'test::E' class: test::C, test::D.
Virtual base classes of the 'test::F' class: test::C, test::D.
Virtual base classes of the 'test::G' class:
Virtual base classes of the 'test::H' class:
*/