54 lines
1.5 KiB
C++
54 lines
1.5 KiB
C++
|
/*!
|
||
|
|
@file
|
||
|
|
Forward declares `boost::hana::greater`.
|
||
|
|
|
||
|
|
@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_GREATER_HPP
|
||
|
|
#define BOOST_HANA_FWD_GREATER_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 greater than `y`.
|
||
|
|
//! @ingroup group-Orderable
|
||
|
|
//!
|
||
|
|
//!
|
||
|
|
//! Signature
|
||
|
|
//! ---------
|
||
|
|
//! Given a Logical `Bool` and two Orderables `A` and `B` with a common
|
||
|
|
//! embedding, the signature is
|
||
|
|
//! @f$ \mathrm{greater} : A \times B \to Bool @f$.
|
||
|
|
//!
|
||
|
|
//! @param x, y
|
||
|
|
//! Two objects to compare.
|
||
|
|
//!
|
||
|
|
//!
|
||
|
|
//! Example
|
||
|
|
//! -------
|
||
|
|
//! @include example/greater.cpp
|
||
|
|
#ifdef BOOST_HANA_DOXYGEN_INVOKED
|
||
|
|
constexpr auto greater = [](auto&& x, auto&& y) -> decltype(auto) {
|
||
|
|
return tag-dispatched;
|
||
|
|
};
|
||
|
|
#else
|
||
|
|
template <typename T, typename U, typename = void>
|
||
|
|
struct greater_impl : greater_impl<T, U, when<true>> { };
|
||
|
|
|
||
|
|
struct greater_t : detail::nested_than<greater_t> {
|
||
|
|
template <typename X, typename Y>
|
||
|
|
constexpr decltype(auto) operator()(X&& x, Y&& y) const;
|
||
|
|
};
|
||
|
|
|
||
|
|
constexpr greater_t greater{};
|
||
|
|
#endif
|
||
|
|
BOOST_HANA_NAMESPACE_END
|
||
|
|
|
||
|
|
#endif // !BOOST_HANA_FWD_GREATER_HPP
|