| 1 | /*! |
| 2 | @file |
| 3 | Forward declares `boost::hana::less_equal`. |
| 4 | |
| 5 | Copyright Louis Dionne 2013-2022 |
| 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_LESS_EQUAL_HPP |
| 11 | #define BOOST_HANA_FWD_LESS_EQUAL_HPP |
| 12 | |
| 13 | #include <boost/hana/config.hpp> |
| 14 | #include <boost/hana/core/when.hpp> |
| 15 | #include <boost/hana/detail/nested_than_fwd.hpp> |
| 16 | |
| 17 | |
| 18 | namespace boost { namespace hana { |
| 19 | //! Returns a `Logical` representing whether `x` is less than or |
| 20 | //! equal to `y`. |
| 21 | //! @ingroup group-Orderable |
| 22 | //! |
| 23 | //! |
| 24 | //! Signature |
| 25 | //! --------- |
| 26 | //! Given a Logical `Bool` and two Orderables `A` and `B` with a common |
| 27 | //! embedding, the signature is |
| 28 | //! @f$ \mathrm{less\_equal} : A \times B \to Bool @f$. |
| 29 | //! |
| 30 | //! @param x, y |
| 31 | //! Two objects to compare. |
| 32 | //! |
| 33 | //! |
| 34 | //! Example |
| 35 | //! ------- |
| 36 | //! @include example/less_equal.cpp |
| 37 | #ifdef BOOST_HANA_DOXYGEN_INVOKED |
| 38 | constexpr auto less_equal = [](auto&& x, auto&& y) { |
| 39 | return tag-dispatched; |
| 40 | }; |
| 41 | #else |
| 42 | template <typename T, typename U, typename = void> |
| 43 | struct less_equal_impl : less_equal_impl<T, U, when<true>> { }; |
| 44 | |
| 45 | struct less_equal_t : detail::nested_than<less_equal_t> { |
| 46 | template <typename X, typename Y> |
| 47 | constexpr auto operator()(X&& x, Y&& y) const; |
| 48 | }; |
| 49 | |
| 50 | BOOST_HANA_INLINE_VARIABLE constexpr less_equal_t less_equal{}; |
| 51 | #endif |
| 52 | }} // end namespace boost::hana |
| 53 | |
| 54 | #endif // !BOOST_HANA_FWD_LESS_EQUAL_HPP |
| 55 | |