#include <type_traits>
-BOOST_HANA_NAMESPACE_BEGIN
+namespace boost { namespace hana {
//! @cond
template <typename X>
constexpr decltype(auto) negate_t::operator()(X&& x) const {
static constexpr decltype(auto) apply(X&& x)
{ return -static_cast<X&&>(x); }
};
-BOOST_HANA_NAMESPACE_END
+}} // end namespace boost::hana
#endif // !BOOST_HANA_NEGATE_HPP