boost/type_traits/is_union.hpp
// (C) Copyright Dave Abrahams, Steve Cleary, Beman Dawes, Howard
// Hinnant & John Maddock 2000.
// 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).
//
// See http://www.boost.org/libs/type_traits for most recent version including documentation.
#ifndef BOOST_TT_IS_UNION_HPP_INCLUDED
#define BOOST_TT_IS_UNION_HPP_INCLUDED
#include <boost/type_traits/remove_cv.hpp>
#include <boost/type_traits/config.hpp>
#include <boost/type_traits/intrinsics.hpp>
// should be the last #include
#include <boost/type_traits/detail/bool_trait_def.hpp>
namespace boost {
namespace detail {
#ifndef __GNUC__
template <typename T> struct is_union_impl
{
typedef typename remove_cv<T>::type cvt;
#ifdef BOOST_IS_UNION
BOOST_STATIC_CONSTANT(bool, value = BOOST_IS_UNION(cvt));
#else
BOOST_STATIC_CONSTANT(bool, value = false);
#endif
};
#else
//
// using remove_cv here generates a whole load of needless
// warnings with gcc, since it doesn't do any good with gcc
// in any case (at least at present), just remove it:
//
template <typename T> struct is_union_impl
{
#ifdef BOOST_IS_UNION
BOOST_STATIC_CONSTANT(bool, value = BOOST_IS_UNION(T));
#else
BOOST_STATIC_CONSTANT(bool, value = false);
#endif
};
#endif
} // namespace detail
BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_union,T,::boost::detail::is_union_impl<T>::value)
} // namespace boost
#include <boost/type_traits/detail/bool_trait_undef.hpp>
#endif // BOOST_TT_IS_UNION_HPP_INCLUDED