ceph/src/boost/boost/spirit/home/x3/directive/skip.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2014 Joel de Guzman
   3     Copyright (c) 2013 Agustin Berge
   4
   5     Distributed under the Boost Software License, Version 1.0. (See accompanying
   6     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   7 =============================================================================*/
   8 #if !defined(BOOST_SPIRIT_X3_SKIP_JANUARY_26_2008_0422PM)
   9 #define BOOST_SPIRIT_X3_SKIP_JANUARY_26_2008_0422PM
  10
  11 #include <boost/spirit/home/x3/support/context.hpp>
  12 #include <boost/spirit/home/x3/support/unused.hpp>
  13 #include <boost/spirit/home/x3/core/skip_over.hpp>
  14 #include <boost/spirit/home/x3/core/parser.hpp>
  15 #include <boost/utility/enable_if.hpp>
  16
  17 namespace boost { namespace spirit { namespace x3
  18 {
  19     template <typename Subject>
  20     struct reskip_directive : unary_parser<Subject, reskip_directive<Subject>>
  21     {
  22         typedef unary_parser<Subject, reskip_directive<Subject>> base_type;
  23         static bool const is_pass_through_unary = true;
  24         static bool const handles_container = Subject::handles_container;
  25
  26         constexpr reskip_directive(Subject const& subject)
  27           : base_type(subject) {}
  28
  29         template <typename Iterator, typename Context
  30           , typename RContext, typename Attribute>
  31         typename disable_if<has_skipper<Context>, bool>::type
  32         parse(Iterator& first, Iterator const& last
  33           , Context const& context, RContext& rcontext, Attribute& attr) const
  34         {
  35             auto const& skipper =
  36                 detail::get_unused_skipper(x3::get<skipper_tag>(context));
  37
  38             return this->subject.parse(
  39                 first, last
  40               , make_context<skipper_tag>(skipper, context)
  41               , rcontext
  42               , attr);
  43         }
  44         template <typename Iterator, typename Context
  45           , typename RContext, typename Attribute>
  46         typename enable_if<has_skipper<Context>, bool>::type
  47         parse(Iterator& first, Iterator const& last
  48           , Context const& context, RContext& rcontext, Attribute& attr) const
  49         {
  50             return this->subject.parse(
  51                 first, last
  52               , context
  53               , rcontext
  54               , attr);
  55         }
  56     };
  57
  58     template <typename Subject, typename Skipper>
  59     struct skip_directive : unary_parser<Subject, skip_directive<Subject, Skipper>>
  60     {
  61         typedef unary_parser<Subject, skip_directive<Subject, Skipper>> base_type;
  62         static bool const is_pass_through_unary = true;
  63         static bool const handles_container = Subject::handles_container;
  64
  65         constexpr skip_directive(Subject const& subject, Skipper const& skipper)
  66           : base_type(subject)
  67           , skipper(skipper)
  68         {}
  69
  70         template <typename Iterator, typename Context
  71           , typename RContext, typename Attribute>
  72         bool parse(Iterator& first, Iterator const& last
  73           , Context const& context, RContext& rcontext, Attribute& attr) const
  74         {
  75             return this->subject.parse(
  76                 first, last
  77               , make_context<skipper_tag>(skipper, context)
  78               , rcontext
  79               , attr);
  80         }
  81
  82         Skipper const skipper;
  83     };
  84
  85     struct reskip_gen
  86     {
  87         template <typename Skipper>
  88         struct skip_gen
  89         {
  90             constexpr skip_gen(Skipper const& skipper)
  91               : skipper_(skipper) {}
  92
  93             template <typename Subject>
  94             constexpr skip_directive<typename extension::as_parser<Subject>::value_type, Skipper>
  95             operator[](Subject const& subject) const
  96             {
  97                 return { as_parser(subject), skipper_ };
  98             }
  99
 100             Skipper skipper_;
 101         };
 102
 103         template <typename Skipper>
 104         constexpr skip_gen<Skipper> const operator()(Skipper const& skipper) const
 105         {
 106             return { skipper };
 107         }
 108
 109         template <typename Subject>
 110         constexpr reskip_directive<typename extension::as_parser<Subject>::value_type>
 111         operator[](Subject const& subject) const
 112         {
 113             return { as_parser(subject) };
 114         }
 115     };
 116
 117     constexpr auto skip = reskip_gen{};
 118 }}}
 119
 120 #endif