| // Copyright Daniel Wallin, David Abrahams 2005. |
| // 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) |
| |
| #ifndef BOOST_PARAMETER_AUX_YESNO_HPP |
| #define BOOST_PARAMETER_AUX_YESNO_HPP |
| |
| namespace boost { namespace parameter { namespace aux { |
| |
| // types used with the "sizeof trick" to capture the results of |
| // overload resolution at compile-time. |
| typedef char yes_tag; |
| typedef char (&no_tag)[2]; |
| }}} // namespace boost::parameter::aux |
| |
| #include <boost/mpl/bool.hpp> |
| |
| namespace boost { namespace parameter { namespace aux { |
| |
| // mpl::true_ and mpl::false_ are not distinguishable by sizeof(), |
| // so we pass them through these functions to get a type that is. |
| ::boost::parameter::aux::yes_tag to_yesno(::boost::mpl::true_); |
| ::boost::parameter::aux::no_tag to_yesno(::boost::mpl::false_); |
| }}} // namespace boost::parameter::aux |
| |
| #include <boost/parameter/config.hpp> |
| |
| #if defined(BOOST_PARAMETER_CAN_USE_MP11) |
| #include <boost/mp11/integral.hpp> |
| |
| namespace boost { namespace parameter { namespace aux { |
| |
| // mp11::mp_true and mp11::mp_false are not distinguishable by sizeof(), |
| // so we pass them through these functions to get a type that is. |
| ::boost::parameter::aux::yes_tag to_yesno(::boost::mp11::mp_true); |
| ::boost::parameter::aux::no_tag to_yesno(::boost::mp11::mp_false); |
| }}} // namespace boost::parameter::aux |
| |
| #endif // BOOST_PARAMETER_CAN_USE_MP11 |
| #endif // include guard |
| |