Boost LA

#include <boost/la/sw.hpp>

namespace
boost
    {
    namespace
    la
        {
        struct _x_;
        struct _y_;
        struct _z_;
        struct _w_;
        struct _0_;
        struct _1_;
        
        template <int I1,int I2,...int IN>
        -unspecified-return-type- sw();
        
        template <class A1,class A2,...class AN>
        -unspecified-return-type- sw();
        }
    }