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Enhancing Fusion and as_vector transform manipulation

I am trying to figure out how to use Fusion, and with this simple example:

#include <boost/fusion/include/is_sequence.hpp>
#include <boost/fusion/include/as_vector.hpp>
#include <boost/fusion/include/make_vector.hpp>
#include <boost/fusion/include/transform.hpp>

template< typename T >
struct S {
    typedef T type;
};

struct S_f {
    template< typename T >
    struct result {
        typedef typename T::type type;
    };
};

int main () {
    using namespace boost;
    typedef fusion::vector<S<int>> from_type;
    BOOST_MPL_ASSERT((fusion::traits::is_sequence< fusion::vector< int > > ));

    typedef fusion::result_of::transform< from_type, S_f >::type to_type;
    BOOST_MPL_ASSERT((fusion::traits::is_sequence< to_type > ));

    typedef fusion::result_of::as_vector< to_type >::type value_type; // error
}

Assertions are passed, but the typedef for value_type does not work with the error below. I could not finance any inconsistencies between code and documents and without any corrections elsewhere in stackoverflow or to raise mailing lists.

AFAICT is the correct code: the result of applying the transformation metafile is transform_view, and transform_view is a sequence, as shown by the transmitting statements. However, applying the as_vector metafile to transform_view fails. What gives?!

. mpl. , MPL SO, , , MPL. , MPL.

clang++ -std=c++1z -c t.cpp
In file included from main.cpp:4:
In file included from /usr/local/include/boost/fusion/include/transform.hpp:11:
In file included from /usr/local/include/boost/fusion/algorithm/transformation/transform.hpp:11:
In file included from /usr/local/include/boost/fusion/view/transform_view/transform_view.hpp:15:
In file included from /usr/local/include/boost/fusion/view/transform_view/transform_view_iterator.hpp:18:
/usr/local/include/boost/fusion/view/transform_view/detail/value_of_impl.hpp:37:74: error: no type named 'type' in 'boost::mpl::apply<boost::fusion::detail::apply_transform_result<S_f>, S<int>, mpl_::na, mpl_::na, mpl_::na, mpl_::na>'
                typedef typename mpl::apply<transform_type, value_type>::type type;
                        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~
/usr/local/include/boost/fusion/iterator/value_of.hpp:52:15: note: in instantiation of template class 'boost::fusion::extension::value_of_impl<boost::fusion::transform_view_iterator_tag>::apply<boost::fusion::transform_view_iterator<boost::fusion::vector_iterator<boost::fusion::vector<S<int>, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_>, 0>, S_f> >' requested here
            : extension::value_of_impl<typename detail::tag_of<Iterator>::type>::
              ^
/usr/local/include/boost/fusion/container/vector/detail/cpp03/preprocessed/as_vector10.hpp:19:49: note: in instantiation of template class 'boost::fusion::result_of::value_of<boost::fusion::transform_view_iterator<boost::fusion::vector_iterator<boost::fusion::vector<S<int>, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_>, 0>, S_f> >' requested here
            typedef typename fusion::result_of::value_of<I0>::type T0;
                                                ^
/usr/local/include/boost/fusion/container/vector/convert.hpp:26:17: note: in instantiation of template class 'boost::fusion::detail::barrier::as_vector<1>::apply<boost::fusion::transform_view_iterator<boost::fusion::vector_iterator<boost::fusion::vector<S<int>, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_>, 0>, S_f> >' requested here
                template apply<typename result_of::begin<Sequence>::type>::type
                ^
main.cpp:26:32: note: in instantiation of template class 'boost::fusion::result_of::as_vector<boost::fusion::transform_view<boost::fusion::vector<S<int>, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_>, S_f, boost::fusion::void_> >' requested here
    typedef fusion::result_of::as_vector< to_type >::type value_type; // error
                               ^
1 error generated.
+4
1

, , , . transform , F . , , , : , . result_of<F(T)>::type .

, transform:

struct S_f {
    template< typename T >
    struct result {
        typedef typename T::type type;
    };
};

. . , Boost.Fusion Boost.MPL . , , transform<> - , . as_vector<>, , , .

, result :

struct S_f {
    template< typename T >
    typename T::type operator()(T );
};

, . .

+5

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