qi/auxiliary/eol.hpp

0001 /*=============================================================================
0002     Copyright (c) 2001-2011 Hartmut Kaiser
0003     Copyright (c) 2001-2011 Joel de Guzman
0004
0005     Distributed under the Boost Software License, Version 1.0. (See accompanying
0006     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0007 ==============================================================================*/
0008 #if !defined(BOOST_SPIRIT_EOL_APRIL_18_2008_0751PM)
0009 #define BOOST_SPIRIT_EOL_APRIL_18_2008_0751PM
0010
0011 #if defined(_MSC_VER)
0012 #pragma once
0013 #endif
0014
0015 #include <boost/mpl/bool.hpp>
0016 #include <boost/spirit/home/qi/domain.hpp>
0017 #include <boost/spirit/home/qi/parser.hpp>
0018 #include <boost/spirit/home/qi/meta_compiler.hpp>
0019 #include <boost/spirit/home/qi/skip_over.hpp>
0020 #include <boost/spirit/home/support/common_terminals.hpp>
0021
0022 namespace boost { namespace spirit
0023 {
0024     ///////////////////////////////////////////////////////////////////////////
0025     // Enablers
0026     ///////////////////////////////////////////////////////////////////////////
0027     template <>
0028     struct use_terminal<qi::domain, tag::eol>       // enables eol
0029       : mpl::true_ {};
0030 }}
0031
0032 namespace boost { namespace spirit { namespace qi
0033 {
0034 #ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
0035     using spirit::eol;
0036 #endif
0037     using spirit::eol_type;
0038
0039     struct eol_parser : primitive_parser<eol_parser>
0040     {
0041         template <typename Context, typename Iterator>
0042         struct attribute
0043         {
0044             typedef unused_type type;
0045         };
0046
0047         template <typename Iterator, typename Context
0048           , typename Skipper, typename Attribute>
0049         bool parse(Iterator& first, Iterator const& last
0050           , Context& /*context*/, Skipper const& skipper
0051           , Attribute& /*attr*/) const
0052         {
0053             qi::skip_over(first, last, skipper);
0054
0055             Iterator it = first;
0056             bool matched = false;
0057             if (it != last && *it == '\r')  // CR
0058             {
0059                 matched = true;
0060                 ++it;
0061             }
0062             if (it != last && *it == '\n')  // LF
0063             {
0064                 matched = true;
0065                 ++it;
0066             }
0067
0068             if (!matched)
0069                 return false;
0070
0071             first = it;
0072             return true;
0073         }
0074
0075         template <typename Context>
0076         info what(Context& /*context*/) const
0077         {
0078             return info("eol");
0079         }
0080     };
0081
0082     ///////////////////////////////////////////////////////////////////////////
0083     // Parser generators: make_xxx function (objects)
0084     ///////////////////////////////////////////////////////////////////////////
0085     template <typename Modifiers>
0086     struct make_primitive<tag::eol, Modifiers>
0087     {
0088         typedef eol_parser result_type;
0089         result_type operator()(unused_type, unused_type) const
0090         {
0091             return result_type();
0092         }
0093     };
0094 }}}
0095
0096 #endif
0097
0098