ceph/src/boost/boost/metaparse/v1/cpp11/sequence.hpp

   1 #ifndef BOOST_METAPARSE_V1_CPP11_SEQUENCE_HPP
   2 #define BOOST_METAPARSE_V1_CPP11_SEQUENCE_HPP
   3
   4 // Copyright Abel Sinkovics (abel@sinkovics.hu)  2018.
   5 // Distributed under the Boost Software License, Version 1.0.
   6 //    (See accompanying file LICENSE_1_0.txt or copy at
   7 //          http://www.boost.org/LICENSE_1_0.txt)
   8
   9 #include <boost/metaparse/v1/cpp11/impl/push_front_result.hpp>
  10
  11 #include <boost/metaparse/v1/get_remaining.hpp>
  12 #include <boost/metaparse/v1/get_position.hpp>
  13 #include <boost/metaparse/v1/is_error.hpp>
  14 #include <boost/metaparse/v1/return_.hpp>
  15 #include <boost/metaparse/v1/transform.hpp>
  16
  17 #include <boost/mpl/eval_if.hpp>
  18 #include <boost/mpl/vector.hpp>
  19
  20 namespace boost
  21 {
  22   namespace metaparse
  23   {
  24     namespace v1
  25     {
  26       template <class... Ps>
  27       struct sequence;
  28
  29       template <>
  30       struct sequence<> : return_<boost::mpl::vector<>> {};
  31
  32       template <class P, class... Ps>
  33       struct sequence<P, Ps...>
  34       {
  35       private:
  36         template <class Res>
  37         struct apply_unchecked :
  38           transform<
  39             sequence<Ps...>,
  40             impl::push_front_result<Res>
  41           >::template apply<
  42             typename get_remaining<Res>::type,
  43             typename get_position<Res>::type
  44           >
  45         {};
  46       public:
  47         typedef sequence type;
  48
  49         template <class S, class Pos>
  50         struct apply :
  51           boost::mpl::eval_if<
  52             typename is_error<typename P::template apply<S, Pos>>::type,
  53             typename P::template apply<S, Pos>,
  54             apply_unchecked<typename P::template apply<S, Pos>>
  55           >
  56         {};
  57       };
  58     }
  59   }
  60 }
  61
  62 #endif