template<
      typename SourceTag
    , typename TargetTag
    >
struct[numeric\_cast](./numeric-cast.html);

#include <[boost/mpl/numeric\_cast.hpp](../../../../boost/mpl/numeric_cast.hpp)>

typedef[apply\_wrap](./apply-wrap.html)2<[numeric\_cast](./numeric-cast.html)<x_tag,y_tag>,x >::type r;

struct complex_tag :[int\_](./int.html)<10> {};

template< typename Re, typename Im > struct complex
{
    typedef complex_tag tag;
    typedef complex type;
    typedef Re real;
    typedef Im imag;
};

template< typename C > struct real : C::real {};
template< typename C > struct imag : C::imag {};

namespace boost { namespace mpl {

template<> struct[numeric\_cast](./numeric-cast.html)< integral_c_tag,complex_tag >
{
    template< typename N > struct[apply](./apply.html): complex< N,[integral\_c](./integral-c.html)< typename N::[value\_type](./value-type.html), 0 > >
    {
    };
};

template<>
struct plus_impl< complex_tag,complex_tag >
{
    template< typename N1, typename N2 > struct[apply](./apply.html): complex<[plus](./plus.html)< typename N1::real, typename N2::real >
            ,[plus](./plus.html)< typename N1::imag, typename N2::imag >
            >
    {
    };
};

}}

typedef[int\_](./int.html)<2> i;
typedef complex<[int\_](./int.html)<5>,[int\_](./int.html)<-1> > c1;
typedef complex<[int\_](./int.html)<-5>,[int\_](./int.html)<1> > c2;

typedef[plus](./plus.html)<c1,i> r4;[BOOST\_MPL\_ASSERT\_RELATION](./assert-relation.html)( real<r4>::value, ==, 7 );[BOOST\_MPL\_ASSERT\_RELATION](./assert-relation.html)( imag<r4>::value, ==, -1 );

typedef[plus](./plus.html)<i,c2> r5;[BOOST\_MPL\_ASSERT\_RELATION](./assert-relation.html)( real<r5>::value, ==, -3 );[BOOST\_MPL\_ASSERT\_RELATION](./assert-relation.html)( imag<r5>::value, ==, 1 );