query_static.cpp
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//
// cpp11/query_static.cpp
// ~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2020 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 "asio/query.hpp"
#include <cassert>
struct prop
{
};
struct object
{
};
namespace asio {
template<>
struct is_applicable_property<object, prop>
{
static constexpr bool value = true;
};
namespace traits {
template<>
struct static_query<object, prop>
{
static constexpr bool is_valid = true;
static constexpr bool is_noexcept = true;
typedef int result_type;
static constexpr int value() { return 123; }
};
} // namespace traits
} // namespace asio
int main()
{
object o1 = {};
int result1 = asio::query(o1, prop());
assert(result1 == 123);
(void)result1;
const object o2 = {};
int result2 = asio::query(o2, prop());
assert(result2 == 123);
(void)result2;
constexpr object o3 = {};
constexpr int result3 = asio::query(o3, prop());
assert(result3 == 123);
(void)result3;
}