69 lines
1.4 KiB
C++
69 lines
1.4 KiB
C++
|
/* Copyright 2016-2017 Joaquin M Lopez Munoz.
|
||
|
|
* 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)
|
||
|
|
*
|
||
|
|
* See http://www.boost.org/libs/poly_collection for library home page.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef BOOST_POLY_COLLECTION_DETAIL_IS_FINAL_HPP
|
||
|
|
#define BOOST_POLY_COLLECTION_DETAIL_IS_FINAL_HPP
|
||
|
|
|
||
|
|
#if defined(_MSC_VER)
|
||
|
|
#pragma once
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#include <boost/type_traits/is_final.hpp>
|
||
|
|
#include <type_traits>
|
||
|
|
|
||
|
|
/* technique explained at
|
||
|
|
* http://bannalia.blogspot.com/2016/09/compile-time-checking-existence-of.html
|
||
|
|
*/
|
||
|
|
|
||
|
|
namespace boost{
|
||
|
|
namespace poly_collection{
|
||
|
|
namespace detail{
|
||
|
|
namespace is_final_fallback{
|
||
|
|
|
||
|
|
template<typename T> using is_final=boost::is_final<T>;
|
||
|
|
|
||
|
|
struct hook{};
|
||
|
|
|
||
|
|
}}}}
|
||
|
|
|
||
|
|
namespace std{
|
||
|
|
|
||
|
|
template<>
|
||
|
|
struct is_void< ::boost::poly_collection::detail::is_final_fallback::hook>:
|
||
|
|
std::false_type
|
||
|
|
{
|
||
|
|
template<typename T>
|
||
|
|
static constexpr bool is_final_f()
|
||
|
|
{
|
||
|
|
using namespace ::boost::poly_collection::detail::is_final_fallback;
|
||
|
|
return is_final<T>::value;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
} /* namespace std */
|
||
|
|
|
||
|
|
namespace boost{
|
||
|
|
|
||
|
|
namespace poly_collection{
|
||
|
|
|
||
|
|
namespace detail{
|
||
|
|
|
||
|
|
template<typename T>
|
||
|
|
struct is_final:std::integral_constant<
|
||
|
|
bool,
|
||
|
|
std::is_void<is_final_fallback::hook>::template is_final_f<T>()
|
||
|
|
>{};
|
||
|
|
|
||
|
|
} /* namespace poly_collection::detail */
|
||
|
|
|
||
|
|
} /* namespace poly_collection */
|
||
|
|
|
||
|
|
} /* namespace boost */
|
||
|
|
|
||
|
|
#endif
|