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//
// cpp11/can_prefer_not_preferable_member_prefer.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
{
static constexpr bool is_preferable = false;
};
template <int>
struct object
{
template <int N>
constexpr object<N> prefer(prop<N>) const
{
return object<N>();
}
};
namespace boost {
namespace asio {
template<int N, int M>
struct is_applicable_property<object<N>, prop<M> >
{
static constexpr bool value = true;
};
} // namespace asio
} // namespace boost
int main()
{
static_assert(!boost::asio::can_prefer<object<1>, prop<2>>::value, "");
static_assert(!boost::asio::can_prefer<object<1>, prop<2>, prop<3>>::value, "");
static_assert(!boost::asio::can_prefer<object<1>, prop<2>, prop<3>, prop<4>>::value, "");
static_assert(!boost::asio::can_prefer<const object<1>, prop<2>>::value, "");
static_assert(!boost::asio::can_prefer<const object<1>, prop<2>, prop<3>>::value, "");
static_assert(!boost::asio::can_prefer<const object<1>, prop<2>, prop<3>, prop<4>>::value, "");
}
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