ext-boost/boost/range/detail/has_member_size.hpp

67 lines
1.5 KiB
C++
Raw Normal View History

2014-12-07 19:44:55 +00:00
// Boost.Range library
//
// Copyright Neil Groves 2014.
//
// Use, modification and distribution are subject to 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).
//
// For more information, see http://www.boost.org/libs/range/
//
#ifndef BOOST_RANGE_DETAIL_HAS_MEMBER_SIZE_HPP
#define BOOST_RANGE_DETAIL_HAS_MEMBER_SIZE_HPP
#include <boost/type_traits/is_class.hpp>
#include <boost/type_traits/is_member_function_pointer.hpp>
#include <boost/mpl/and.hpp>
#include <boost/mpl/bool.hpp>
#include <boost/cstdint.hpp>
namespace boost
{
namespace range_detail
{
template<class T>
class has_member_size_impl
{
private:
template<class U, U>
class check
{
};
template<class C>
static boost::uint8_t f(check<std::size_t(C::*)(void) const, &C::size>*);
template<class C>
static boost::uint16_t f(...);
public:
static const bool value =
(sizeof(f<T>(0)) == sizeof(boost::uint8_t));
typedef typename mpl::if_c<
(sizeof(f<T>(0)) == sizeof(boost::uint8_t)),
mpl::true_,
mpl::false_
>::type type;
};
template<class T>
struct has_member_size
{
typedef typename mpl::and_<
typename is_class<T>::type,
typename has_member_size_impl<const T>::type
>::type type;
static const bool value =
is_class<T>::value && has_member_size_impl<const T>::value;
};
} // namespace range_detail
}// namespace boost
#endif // include guard