/*! @file Forward declares `boost::hana::symmetric_difference`. Copyright Louis Dionne 2013-2022 Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) */ #ifndef BOOST_HANA_FWD_SYMMETRIC_DIFFERENCE_HPP #define BOOST_HANA_FWD_SYMMETRIC_DIFFERENCE_HPP #include <boost/hana/config.hpp> #include <boost/hana/core/when.hpp> namespace boost { namespace hana { // Note: This function is documented per datatype/concept only. //! @cond template <typename S, typename = void> struct symmetric_difference_impl : symmetric_difference_impl<S, when<true>> { }; //! @endcond struct symmetric_difference_t { template <typename Xs, typename Ys> constexpr auto operator()(Xs&&, Ys&&) const; }; BOOST_HANA_INLINE_VARIABLE constexpr symmetric_difference_t symmetric_difference{}; }} // end namespace boost::hana #endif // !BOOST_HANA_FWD_SYMMETRIC_DIFFERENCE_HPP