mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-18 13:42:02 +00:00
75 lines
1.7 KiB
C++
75 lines
1.7 KiB
C++
#ifndef POINTEE_DWA200415_HPP
|
|
# define POINTEE_DWA200415_HPP
|
|
|
|
//
|
|
// Copyright David Abrahams 2004. Use, modification and distribution is
|
|
// 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)
|
|
//
|
|
// typename pointee<P>::type provides the pointee type of P.
|
|
//
|
|
// For example, it is T for T* and X for shared_ptr<X>.
|
|
//
|
|
// http://www.boost.org/libs/iterator/doc/pointee.html
|
|
//
|
|
|
|
# include <boost/detail/is_incrementable.hpp>
|
|
# include <boost/iterator/iterator_traits.hpp>
|
|
# include <boost/type_traits/add_const.hpp>
|
|
# include <boost/type_traits/remove_cv.hpp>
|
|
# include <boost/mpl/if.hpp>
|
|
# include <boost/mpl/eval_if.hpp>
|
|
|
|
namespace boost {
|
|
|
|
namespace detail
|
|
{
|
|
template <class P>
|
|
struct smart_ptr_pointee
|
|
{
|
|
typedef typename P::element_type type;
|
|
};
|
|
|
|
template <class Iterator>
|
|
struct iterator_pointee
|
|
{
|
|
typedef typename iterator_traits<Iterator>::value_type value_type;
|
|
|
|
struct impl
|
|
{
|
|
template <class T>
|
|
static char test(T const&);
|
|
|
|
static char (& test(value_type&) )[2];
|
|
|
|
static Iterator& x;
|
|
};
|
|
|
|
BOOST_STATIC_CONSTANT(bool, is_constant = sizeof(impl::test(*impl::x)) == 1);
|
|
|
|
typedef typename mpl::if_c<
|
|
# if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x551))
|
|
::boost::detail::iterator_pointee<Iterator>::is_constant
|
|
# else
|
|
is_constant
|
|
# endif
|
|
, typename add_const<value_type>::type
|
|
, value_type
|
|
>::type type;
|
|
};
|
|
}
|
|
|
|
template <class P>
|
|
struct pointee
|
|
: mpl::eval_if<
|
|
detail::is_incrementable<P>
|
|
, detail::iterator_pointee<P>
|
|
, detail::smart_ptr_pointee<P>
|
|
>
|
|
{
|
|
};
|
|
|
|
} // namespace boost
|
|
|
|
#endif // POINTEE_DWA200415_HPP
|