x3/char/char_set.hpp

0001 /*=============================================================================
0002     Copyright (c) 2001-2014 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 #if !defined(BOOST_SPIRIT_X3_CHAR_SET_OCT_12_2014_1051AM)
0008 #define BOOST_SPIRIT_X3_CHAR_SET_OCT_12_2014_1051AM
0009
0010 #include <boost/spirit/home/x3/char/char_parser.hpp>
0011 #include <boost/spirit/home/x3/char/detail/cast_char.hpp>
0012 #include <boost/spirit/home/x3/support/traits/string_traits.hpp>
0013 #include <boost/spirit/home/x3/support/utility/utf8.hpp>
0014 #include <boost/spirit/home/x3/support/no_case.hpp>
0015 #include <boost/spirit/home/support/char_set/basic_chset.hpp>
0016
0017 #include <boost/type_traits/is_same.hpp>
0018
0019 namespace boost { namespace spirit { namespace x3
0020 {
0021     ///////////////////////////////////////////////////////////////////////////
0022     // Parser for a character range
0023     ///////////////////////////////////////////////////////////////////////////
0024     template <typename Encoding, typename Attribute = typename Encoding::char_type>
0025     struct char_range
0026       : char_parser< char_range<Encoding, Attribute> >
0027     {
0028
0029         typedef typename Encoding::char_type char_type;
0030         typedef Encoding encoding;
0031         typedef Attribute attribute_type;
0032         static bool const has_attribute =
0033             !is_same<unused_type, attribute_type>::value;
0034
0035
0036         constexpr char_range(char_type from_, char_type to_)
0037           : from(from_), to(to_) {}
0038
0039         template <typename Char, typename Context>
0040         bool test(Char ch_, Context const& context) const
0041         {
0042
0043             char_type ch = char_type(ch_);  // optimize for token based parsing
0044             return (get_case_compare<encoding>(context)(ch, from) >= 0)
0045                && (get_case_compare<encoding>(context)(ch , to) <= 0);
0046         }
0047
0048         char_type from, to;
0049     };
0050
0051
0052     ///////////////////////////////////////////////////////////////////////////
0053     // Parser for a character set
0054     ///////////////////////////////////////////////////////////////////////////
0055     template <typename Encoding, typename Attribute = typename Encoding::char_type>
0056     struct char_set : char_parser<char_set<Encoding, Attribute>>
0057     {
0058         typedef typename Encoding::char_type char_type;
0059         typedef Encoding encoding;
0060         typedef Attribute attribute_type;
0061         static bool const has_attribute =
0062             !is_same<unused_type, attribute_type>::value;
0063
0064         template <typename String>
0065         char_set(String const& str)
0066         {
0067             using spirit::x3::detail::cast_char;
0068
0069             auto* definition = traits::get_c_string(str);
0070             auto ch = *definition++;
0071             while (ch)
0072             {
0073                 auto next = *definition++;
0074                 if (next == '-')
0075                 {
0076                     next = *definition++;
0077                     if (next == 0)
0078                     {
0079                         chset.set(cast_char<char_type>(ch));
0080                         chset.set('-');
0081                         break;
0082                     }
0083                     chset.set(
0084                         cast_char<char_type>(ch),
0085                         cast_char<char_type>(next)
0086                     );
0087                 }
0088                 else
0089                 {
0090                     chset.set(cast_char<char_type>(ch));
0091                 }
0092                 ch = next;
0093             }
0094         }
0095
0096         template <typename Char, typename Context>
0097         bool test(Char ch_, Context const& context) const
0098         {
0099             return get_case_compare<encoding>(context).in_set(ch_, chset);
0100         }
0101
0102         support::detail::basic_chset<char_type> chset;
0103     };
0104
0105     template <typename Encoding, typename Attribute>
0106     struct get_info<char_set<Encoding, Attribute>>
0107     {
0108         typedef std::string result_type;
0109         std::string operator()(char_set<Encoding, Attribute> const& /* p */) const
0110         {
0111             return "char-set";
0112         }
0113     };
0114
0115     template <typename Encoding, typename Attribute>
0116     struct get_info<char_range<Encoding, Attribute>>
0117     {
0118         typedef std::string result_type;
0119         std::string operator()(char_range<Encoding, Attribute> const& p) const
0120         {
0121             return "char_range \"" + to_utf8(Encoding::toucs4(p.from)) + '-' + to_utf8(Encoding::toucs4(p.to))+ '"';
0122         }
0123     };
0124
0125 }}}
0126
0127 #endif