ceph/src/boost/libs/spirit/include/boost/spirit/home/x3/directive/seek.hpp

   1 /*=============================================================================
   2     Copyright (c) 2011 Jamboree
   3     Copyright (c) 2014 Lee Clagett
   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_SEEK_APRIL_13_2014_1920PM)
   9 #define BOOST_SPIRIT_X3_SEEK_APRIL_13_2014_1920PM
  10
  11 #include <boost/spirit/home/x3/core/parser.hpp>
  12
  13 namespace boost { namespace spirit { namespace x3
  14 {
  15     template<typename Subject>
  16     struct seek_directive : unary_parser<Subject, seek_directive<Subject>>
  17     {
  18         typedef unary_parser<Subject, seek_directive<Subject>> base_type;
  19         static bool const is_pass_through_unary = true;
  20         static bool const handles_container = Subject::handles_container;
  21
  22         seek_directive(Subject const& subject) :
  23             base_type(subject) {}
  24
  25         template<typename Iterator, typename Context
  26           , typename RContext, typename Attribute>
  27         bool parse(
  28             Iterator& first, Iterator const& last
  29           , Context const& context, RContext& rcontext, Attribute& attr) const
  30         {
  31             Iterator current(first);
  32             for (/**/; current != last; ++current)
  33             {
  34                 if (this->subject.parse(current, last, context, rcontext, attr))
  35                 {
  36                     first = current;
  37                     return true;
  38                 }
  39             }
  40
  41             // Test for when subjects match on input empty. Example:
  42             //     comment = "//" >> seek[eol | eoi]
  43             if (this->subject.parse(current, last, context, rcontext, attr))
  44             {
  45                 first = current;
  46                 return true;
  47             }
  48
  49             return false;
  50         }
  51     };
  52
  53     struct seek_gen
  54     {
  55         template<typename Subject>
  56         seek_directive<typename extension::as_parser<Subject>::value_type>
  57         operator[](Subject const& subject) const
  58         {
  59             return { as_parser(subject) };
  60         }
  61     };
  62
  63     auto const seek = seek_gen{};
  64 }}}
  65
  66 #endif