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        Metafunction that evaluates to mpl::true_
        if a certain type T is a
        conforming Fusion View, mpl::false_
        otherwise. A view is a specialized sequence that does not actually contain
        data. Views hold sequences which may be other views. In general, views are
        held by other views by value, while non-views are held by other views by
        reference. is_view may be
        specialized to accommodate clients providing Fusion conforming views.
      
namespace traits { template <typename T> struct is_view { typedef unspecified type; }; }
| Parameter | Requirement | Description | 
|---|---|---|
| 
                   | Any type | The type to query. | 
typedef traits::is_view<T>::type c;
Return type: An MPL Boolean Constant.
        Semantics: Metafunction that evaluates to
        mpl::true_ if a certain type T
        is a conforming Fusion view, mpl::false_
        otherwise.
      
#include <boost/fusion/support/is_view.hpp> #include <boost/fusion/include/is_view.hpp>
BOOST_MPL_ASSERT_NOT(( traits::is_view<std::vector<int> > )); BOOST_MPL_ASSERT_NOT(( traits::is_view<int> )); using boost::mpl::_ using boost::is_pointer; typedefvector<int*, char, long*, bool, double> vector_type; typedeffilter_view<vector_type, is_pointer<_> > filter_view_type; BOOST_MPL_ASSERT(( traits::is_view<filter_view_type> ));