boost/python/detail/is_wrapper.hpp
// Copyright David Abrahams 2004. 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)
#ifndef IS_WRAPPER_DWA2004723_HPP
# define IS_WRAPPER_DWA2004723_HPP
# include <boost/python/detail/prefix.hpp>
# include <boost/mpl/bool.hpp>
namespace boost { namespace python {
template <class T> class wrapper;
namespace detail
{
typedef char (&is_not_wrapper)[2];
is_not_wrapper is_wrapper_helper(...);
template <class T>
char is_wrapper_helper(wrapper<T> const volatile*);
// A metafunction returning true iff T is [derived from] wrapper<U>
template <class T>
struct is_wrapper
: mpl::bool_<(sizeof(detail::is_wrapper_helper((T*)0)) == 1)>
{};
}}} // namespace boost::python::detail
#endif // IS_WRAPPER_DWA2004723_HPP