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//
// cpp03/prefer_unsupported.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 const bool is_preferable = true;
};
template <int>
struct object
{
};
namespace boost {
namespace asio {
template<int N, int M>
struct is_applicable_property<object<N>, prop<M> >
{
static const bool value = true;
};
} // namespace asio
} // namespace boost
int main()
{
object<1> o1 = {};
const object<1>& o2 = boost::asio::prefer(o1, prop<1>());
assert(&o1 == &o2);
(void)o2;
const object<1> o3 = {};
const object<1>& o4 = boost::asio::prefer(o3, prop<1>());
assert(&o3 == &o4);
(void)o4;
}
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