#ifndef BOOST_METAPARSE_V1_CPP11_NTH_OF_C_HPP #define BOOST_METAPARSE_V1_CPP11_NTH_OF_C_HPP // Copyright Abel Sinkovics (abel@sinkovics.hu) 2017. // Distributed under the Boost Software License, Version 1.0. // (See accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt) #include <boost/metaparse/v1/cpp11/impl/nth_of_c.hpp> #include <boost/metaparse/v1/fail.hpp> #include <boost/metaparse/v1/error/index_out_of_range.hpp> #include <type_traits> namespace boost { namespace metaparse { namespace v1 { template <int N, class... Ps> struct nth_of_c { typedef nth_of_c type; template <class S, class Pos> struct apply : std::conditional< (0 <= N && N < sizeof...(Ps)), impl::nth_of_c<N, S, Pos, Ps...>, typename fail<error::index_out_of_range<0, sizeof...(Ps) - 1, N>> ::template apply<S, Pos> >::type {}; }; template <int N> struct nth_of_c<N> : fail<error::index_out_of_range<0, -1, N>> {}; } } } #endif