ceph/src/boost/libs/metaparse/include/boost/metaparse/v1/one_char.hpp

   1 #ifndef BOOST_METAPARSE_V1_ONE_CHAR_HPP
   2 #define BOOST_METAPARSE_V1_ONE_CHAR_HPP
   3
   4 // Copyright Abel Sinkovics (abel@sinkovics.hu)  2009 - 2011.
   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/error/unexpected_end_of_input.hpp>
  10 #include <boost/metaparse/v1/next_char.hpp>
  11 #include <boost/metaparse/v1/next_line.hpp>
  12 #include <boost/metaparse/v1/accept.hpp>
  13 #include <boost/metaparse/v1/reject.hpp>
  14 #include <boost/metaparse/v1/get_prev_char.hpp>
  15
  16 #include <boost/mpl/empty.hpp>
  17 #include <boost/mpl/eval_if.hpp>
  18 #include <boost/mpl/front.hpp>
  19 #include <boost/mpl/pop_front.hpp>
  20 #include <boost/mpl/bool.hpp>
  21
  22 namespace boost
  23 {
  24   namespace metaparse
  25   {
  26     namespace v1
  27     {
  28       struct one_char
  29       {
  30       private:
  31         template <class C, class Pos>
  32         struct next_pos :
  33           boost::mpl::eval_if<
  34             boost::mpl::bool_<
  35               C::type::value == '\r'
  36               || (
  37                 C::type::value == '\n'
  38                 && get_prev_char<Pos>::type::value != '\r'
  39               )
  40             >,
  41             next_line<Pos, C>,
  42             next_char<Pos, C>
  43           >
  44         {};
  45
  46         template <class S, class NextPos>
  47         struct unchecked :
  48           accept<
  49             typename boost::mpl::front<S>::type,
  50             boost::mpl::pop_front<S>,
  51             NextPos
  52           >
  53         {};
  54       public:
  55         typedef one_char type;
  56
  57         template <class S, class Pos>
  58         struct apply :
  59           boost::mpl::eval_if<
  60             typename boost::mpl::empty<S>::type,
  61             reject<error::unexpected_end_of_input, Pos>,
  62             unchecked<S, next_pos<boost::mpl::front<S>, Pos> >
  63           >
  64         {};
  65       };
  66     }
  67   }
  68 }
  69
  70 #endif
  71