boost/type_traits/detail/detector.hpp
/*
Copyright 2017-2018 Glen Joseph Fernandes
(glenjofe@gmail.com)
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_TT_DETAIL_DETECTOR_HPP_INCLUDED
#define BOOST_TT_DETAIL_DETECTOR_HPP_INCLUDED
#include <boost/type_traits/integral_constant.hpp>
#include <boost/type_traits/make_void.hpp>
namespace boost {
namespace detail {
template<class T>
using detector_t = typename boost::make_void<T>::type;
template<class Default, class, template<class...> class, class...>
struct detector {
using value_t = boost::false_type;
using type = Default;
};
template<class Default, template<class...> class Op, class... Args>
struct detector<Default, detector_t<Op<Args...> >, Op, Args...> {
using value_t = boost::true_type;
using type = Op<Args...>;
};
} /* detail */
} /* boost */
#endif