#include <boost/hana/core/when.hpp>
-BOOST_HANA_NAMESPACE_BEGIN
+namespace boost { namespace hana {
//! Filter a monadic structure using a custom predicate.
//! @ingroup group-MonadPlus
//!
constexpr auto operator()(Xs&& xs, Pred&& pred) const;
};
- constexpr filter_t filter{};
+ BOOST_HANA_INLINE_VARIABLE constexpr filter_t filter{};
#endif
-BOOST_HANA_NAMESPACE_END
+}} // end namespace boost::hana
#endif // !BOOST_HANA_FWD_FILTER_HPP