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//
// cpp14/can_prefer_member_require.cpp
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2025 Christopher M. Kohlhoff (chris at kohlhoff dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#include <boost/asio/prefer.hpp>
#include <cassert>
template <int>
struct prop
{
template <typename> static constexpr bool is_applicable_property_v = true;
static constexpr bool is_preferable = true;
};
template <int>
struct object
{
template <int N>
constexpr object<N> require(prop<N>) const
{
return object<N>();
}
};
int main()
{
static_assert(boost::asio::can_prefer_v<object<1>, prop<2>>, "");
static_assert(boost::asio::can_prefer_v<object<1>, prop<2>, prop<3>>, "");
static_assert(boost::asio::can_prefer_v<object<1>, prop<2>, prop<3>, prop<4>>, "");
static_assert(boost::asio::can_prefer_v<const object<1>, prop<2>>, "");
static_assert(boost::asio::can_prefer_v<const object<1>, prop<2>, prop<3>>, "");
static_assert(boost::asio::can_prefer_v<const object<1>, prop<2>, prop<3>, prop<4>>, "");
}
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