読者です 読者をやめる 読者になる 読者になる

Boost.Fusionのメタ関数アルゴリズム

C++

find
(result_of::endが返ってきたら該当なし)

#include <boost/fusion/container/vector.hpp>
#include <boost/fusion/algorithm/query/find.hpp>
#include <boost/type_traits.hpp>
#include <boost/static_assert.hpp>

using namespace boost;
using namespace boost::fusion;

int main()
{
    typedef vector<int, char, double> seq;
    typedef result_of::find<seq, char>::type result;

    BOOST_STATIC_ASSERT((!is_same<result, result_of::end<seq>::type>::value));
}


filter

#include <boost/fusion/container/vector.hpp>
#include <boost/fusion/algorithm/transformation/filter.hpp>
#include <boost/type_traits.hpp>
#include <boost/static_assert.hpp>

using namespace boost;
using namespace boost::fusion;

int main()
{
    typedef vector<int, char, double, int> seq;
    typedef result_of::filter<seq, int>::type result;

    BOOST_STATIC_ASSERT((is_same<result_of::as_vector<result>::type,
                                 vector<int, int> >::value));
}


filter_if

#include <boost/fusion/container/vector.hpp>
#include <boost/fusion/algorithm/transformation/filter_if.hpp>
#include <boost/type_traits.hpp>
#include <boost/static_assert.hpp>

using namespace boost;
using namespace boost::fusion;

int main()
{
    typedef vector<int, char, double, int> seq;
    typedef result_of::filter_if<seq, is_same<mpl::_, int> >::type result;

    BOOST_STATIC_ASSERT((is_same<result_of::as_vector<result>::type,
                                 vector<int, int> >::value));
}


reverse

#include <boost/fusion/container/vector.hpp>
#include <boost/fusion/algorithm/transformation/reverse.hpp>
#include <boost/type_traits.hpp>
#include <boost/static_assert.hpp>

using namespace boost;
using namespace boost::fusion;

int main()
{
    typedef vector<int, char, double> seq;
    typedef result_of::reverse<seq>::type result;

    BOOST_STATIC_ASSERT((is_same<result_of::as_vector<result>::type,
                                 vector<double, char, int> >::value));
}


zip

#include <boost/fusion/container/vector.hpp>
#include <boost/fusion/algorithm/transformation/zip.hpp>
#include <boost/type_traits.hpp>
#include <boost/static_assert.hpp>

using namespace boost;
using namespace boost::fusion;

int main()
{
    typedef vector<int, char> seq1;
    typedef vector<double, long> seq2;

    typedef fusion::result_of::zip<seq1, seq2>::type result;

    BOOST_STATIC_ASSERT((is_same<fusion::result_of::as_vector<result>::type,
                                 vector<vector<int, double>, vector<char, long> > >::value));
}