50 lines
1.2 KiB
C++
50 lines
1.2 KiB
C++
|
/*!
|
||
|
|
@file
|
||
|
|
Forward declares `boost::hana::reverse`.
|
||
|
|
|
||
|
|
@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_REVERSE_HPP
|
||
|
|
#define BOOST_HANA_FWD_REVERSE_HPP
|
||
|
|
|
||
|
|
#include <boost/hana/config.hpp>
|
||
|
|
#include <boost/hana/core/when.hpp>
|
||
|
|
|
||
|
|
|
||
|
|
BOOST_HANA_NAMESPACE_BEGIN
|
||
|
|
//! Reverse a sequence.
|
||
|
|
//! @ingroup group-Sequence
|
||
|
|
//!
|
||
|
|
//! Specifically, `reverse(xs)` is a new sequence containing the same
|
||
|
|
//! elements as `xs`, except in reverse order.
|
||
|
|
//!
|
||
|
|
//!
|
||
|
|
//! @param xs
|
||
|
|
//! The sequence to reverse.
|
||
|
|
//!
|
||
|
|
//!
|
||
|
|
//! Example
|
||
|
|
//! -------
|
||
|
|
//! @include example/reverse.cpp
|
||
|
|
#ifdef BOOST_HANA_DOXYGEN_INVOKED
|
||
|
|
constexpr auto reverse = [](auto&& xs) {
|
||
|
|
return tag-dispatched;
|
||
|
|
};
|
||
|
|
#else
|
||
|
|
template <typename S, typename = void>
|
||
|
|
struct reverse_impl : reverse_impl<S, when<true>> { };
|
||
|
|
|
||
|
|
struct reverse_t {
|
||
|
|
template <typename Xs>
|
||
|
|
constexpr auto operator()(Xs&& xs) const;
|
||
|
|
};
|
||
|
|
|
||
|
|
constexpr reverse_t reverse{};
|
||
|
|
#endif
|
||
|
|
BOOST_HANA_NAMESPACE_END
|
||
|
|
|
||
|
|
#endif // !BOOST_HANA_FWD_REVERSE_HPP
|