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Diffstat (limited to 'boost/hana/fwd/less_equal.hpp')
-rw-r--r-- | boost/hana/fwd/less_equal.hpp | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/boost/hana/fwd/less_equal.hpp b/boost/hana/fwd/less_equal.hpp new file mode 100644 index 0000000000..9de3d6b779 --- /dev/null +++ b/boost/hana/fwd/less_equal.hpp @@ -0,0 +1,54 @@ +/*! +@file +Forward declares `boost::hana::less_equal`. + +@copyright Louis Dionne 2013-2016 +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_LESS_EQUAL_HPP +#define BOOST_HANA_FWD_LESS_EQUAL_HPP + +#include <boost/hana/config.hpp> +#include <boost/hana/core/when.hpp> +#include <boost/hana/detail/nested_than_fwd.hpp> + + +BOOST_HANA_NAMESPACE_BEGIN + //! Returns a `Logical` representing whether `x` is less than or + //! equal to `y`. + //! @ingroup group-Orderable + //! + //! + //! Signature + //! --------- + //! Given a Logical `Bool` and two Orderables `A` and `B` with a common + //! embedding, the signature is + //! @f$ \mathrm{less\_equal} : A \times B \to Bool @f$. + //! + //! @param x, y + //! Two objects to compare. + //! + //! + //! Example + //! ------- + //! @include example/less_equal.cpp +#ifdef BOOST_HANA_DOXYGEN_INVOKED + constexpr auto less_equal = [](auto&& x, auto&& y) { + return tag-dispatched; + }; +#else + template <typename T, typename U, typename = void> + struct less_equal_impl : less_equal_impl<T, U, when<true>> { }; + + struct less_equal_t : detail::nested_than<less_equal_t> { + template <typename X, typename Y> + constexpr auto operator()(X&& x, Y&& y) const; + }; + + constexpr less_equal_t less_equal{}; +#endif +BOOST_HANA_NAMESPACE_END + +#endif // !BOOST_HANA_FWD_LESS_EQUAL_HPP |