//----------------------------------------------------------------------------- // boost mpl/example/inherit_linearly.cpp source file // See http://www.boost.org for updates, documentation, and revision history. //----------------------------------------------------------------------------- // // Copyright (c) 2002 // Aleksey Gurtovoy // // Permission to use, copy, modify, distribute and sell this software // and its documentation for any purpose is hereby granted without fee, // provided that the above copyright notice appears in all copies and // that both the copyright notice and this permission notice appear in // supporting documentation. No representations are made about the // suitability of this software for any purpose. It is provided "as is" // without express or implied warranty. #include "boost/mpl/inherit_linearly.hpp" #include "boost/mpl/int_c.hpp" #include "boost/mpl/list.hpp" #include namespace mpl = boost::mpl; using namespace mpl::placeholder; template< typename Base, typename T > struct tuple_part : Base { typedef tuple_part type; // note the typedef typedef typename Base::index::next index; friend T& field(tuple_part& t, index) { return t.field_; } T field_; }; struct empty_tuple { typedef mpl::int_c<-1> index; }; typedef mpl::inherit_linearly< mpl::list , tuple_part<_,_> , empty_tuple >::type my_tuple; int main() { my_tuple t; field(t, mpl::int_c<0>()) = -1; field(t, mpl::int_c<1>()) = "text"; field(t, mpl::int_c<2>()) = false; std::cout << field(t, mpl::int_c<0>()) << '\n' << field(t, mpl::int_c<1>()) << '\n' << field(t, mpl::int_c<2>()) << '\n' ; return 0; }