1 /*! 2 @file 3 Forward declares `boost::hana::max`. 4 5 @copyright Louis Dionne 2013-2017 6 Distributed under the Boost Software License, Version 1.0. 7 (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) 8 */ 9 10 #ifndef BOOST_HANA_FWD_MAX_HPP 11 #define BOOST_HANA_FWD_MAX_HPP 12 13 #include <boost/hana/config.hpp> 14 #include <boost/hana/core/when.hpp> 15 16 17 BOOST_HANA_NAMESPACE_BEGIN 18 //! Returns the greatest of its arguments according to the `less` ordering. 19 //! @ingroup group-Orderable 20 //! 21 //! 22 //! @todo Can't specify the signature here either. See `min` for details. 23 //! 24 //! Example 25 //! ------- 26 //! @include example/max.cpp 27 #ifdef BOOST_HANA_DOXYGEN_INVOKED 28 constexpr auto max = [](auto&& x, auto&& y) -> decltype(auto) { 29 return tag-dispatched; 30 }; 31 #else 32 template <typename T, typename U, typename = void> 33 struct max_impl : max_impl<T, U, when<true>> { }; 34 35 struct max_t { 36 template <typename X, typename Y> 37 constexpr decltype(auto) operator()(X&& x, Y&& y) const; 38 }; 39 40 constexpr max_t max{}; 41 #endif 42 BOOST_HANA_NAMESPACE_END 43 44 #endif // !BOOST_HANA_FWD_MAX_HPP 45