x3/directive/raw.hpp

0001 /*=============================================================================
0002     Copyright (c) 2014 Joel de Guzman
0003
0004     Distributed under the Boost Software License, Version 1.0. (See accompanying
0005     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0006 =============================================================================*/
0007 #ifndef BOOST_SPIRIT_X3_DIRECTIVE_RAW_HPP
0008 #define BOOST_SPIRIT_X3_DIRECTIVE_RAW_HPP
0009
0010 #include <boost/spirit/home/x3/core/skip_over.hpp>
0011 #include <boost/spirit/home/x3/core/parser.hpp>
0012 #include <boost/spirit/home/x3/support/traits/move_to.hpp>
0013 #include <boost/spirit/home/x3/support/traits/pseudo_attribute.hpp>
0014 #include <boost/range/iterator_range_core.hpp>
0015
0016 namespace boost { namespace spirit { namespace x3
0017 {
0018     // this is a pseudo attribute type indicating that the parser wants the
0019     // iterator range pointing to the [first, last) matching characters from
0020     // the input iterators.
0021     struct raw_attribute_type {};
0022
0023     template <typename Subject>
0024     struct raw_directive : unary_parser<Subject, raw_directive<Subject>>
0025     {
0026         typedef unary_parser<Subject, raw_directive<Subject> > base_type;
0027         typedef raw_attribute_type attribute_type;
0028         static bool const handles_container = true;
0029         typedef Subject subject_type;
0030
0031         constexpr raw_directive(Subject const& subject)
0032           : base_type(subject) {}
0033
0034         template <typename Iterator, typename Context
0035             , typename RContext, typename Attribute>
0036         bool parse(Iterator& first, Iterator const& last
0037           , Context const& context, RContext& rcontext, Attribute& attr) const
0038         {
0039             x3::skip_over(first, last, context);
0040             Iterator i = first;
0041             if (this->subject.parse(i, last, context, rcontext, unused))
0042             {
0043                 traits::move_to(first, i, attr);
0044                 first = i;
0045                 return true;
0046             }
0047             return false;
0048         }
0049
0050         template <typename Iterator, typename Context, typename RContext>
0051         bool parse(Iterator& first, Iterator const& last
0052           , Context const& context, RContext& rcontext, unused_type) const
0053         {
0054             return this->subject.parse(first, last, context, rcontext, unused);
0055         }
0056     };
0057
0058     struct raw_gen
0059     {
0060         template <typename Subject>
0061         constexpr raw_directive<typename extension::as_parser<Subject>::value_type>
0062         operator[](Subject const& subject) const
0063         {
0064             return { as_parser(subject) };
0065         }
0066     };
0067
0068     constexpr auto raw = raw_gen{};
0069
0070     namespace traits
0071     {
0072         template <typename Context, typename Iterator>
0073         struct pseudo_attribute<Context, raw_attribute_type, Iterator>
0074         {
0075             using attribute_type = raw_attribute_type;
0076             using type = boost::iterator_range<Iterator>;
0077
0078             static type call(Iterator& first, Iterator const& last, attribute_type)
0079             {
0080                 return { first, last };
0081             }
0082         };
0083     }
0084 }}}
0085
0086 #endif