58 lines
1.0 KiB
C++
58 lines
1.0 KiB
C++
//
|
|
// cpp03/query_free.cpp
|
|
// ~~~~~~~~~~~~~~~~~~~~
|
|
//
|
|
// Copyright (c) 2003-2021 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/query.hpp>
|
|
#include <cassert>
|
|
|
|
struct prop
|
|
{
|
|
};
|
|
|
|
struct object
|
|
{
|
|
friend int query(const object&, prop) { return 123; }
|
|
};
|
|
|
|
namespace boost {
|
|
namespace asio {
|
|
|
|
template<>
|
|
struct is_applicable_property<object, prop>
|
|
{
|
|
static const bool value = true;
|
|
};
|
|
|
|
namespace traits {
|
|
|
|
template<>
|
|
struct query_free<object, prop>
|
|
{
|
|
static const bool is_valid = true;
|
|
static const bool is_noexcept = true;
|
|
typedef int result_type;
|
|
};
|
|
|
|
} // namespace traits
|
|
} // namespace asio
|
|
} // namespace boost
|
|
|
|
int main()
|
|
{
|
|
object o1 = {};
|
|
int result1 = boost::asio::query(o1, prop());
|
|
assert(result1 == 123);
|
|
(void)result1;
|
|
|
|
const object o2 = {};
|
|
int result2 = boost::asio::query(o2, prop());
|
|
assert(result2 == 123);
|
|
(void)result2;
|
|
}
|