49 lines
916 B
C++
49 lines
916 B
C++
//
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// cpp03/prefer_unsupported.cpp
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// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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//
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// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
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//
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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//
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#include <boost/asio/prefer.hpp>
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#include <cassert>
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template <int>
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struct prop
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{
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static const bool is_preferable = true;
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};
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template <int>
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struct object
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{
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};
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namespace boost {
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namespace asio {
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template<int N, int M>
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struct is_applicable_property<object<N>, prop<M> >
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{
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static const bool value = true;
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};
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} // namespace asio
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} // namespace boost
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int main()
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{
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object<1> o1 = {};
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const object<1>& o2 = boost::asio::prefer(o1, prop<1>());
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assert(&o1 == &o2);
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(void)o2;
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const object<1> o3 = {};
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const object<1>& o4 = boost::asio::prefer(o3, prop<1>());
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assert(&o3 == &o4);
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(void)o4;
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}
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