x3/char/negated_char_parser.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_NEGATED_CHAR_PARSER_APR_16_2006_0906AM)
0008 #define BOOST_SPIRIT_X3_NEGATED_CHAR_PARSER_APR_16_2006_0906AM
0009
0010 #include <boost/spirit/home/x3/support/traits/attribute_of.hpp>
0011 #include <boost/spirit/home/x3/support/traits/has_attribute.hpp>
0012 #include <boost/spirit/home/x3/char/char_parser.hpp>
0013
0014 namespace boost { namespace spirit { namespace x3
0015 {
0016     ///////////////////////////////////////////////////////////////////////////
0017     // negated_char_parser handles ~cp expressions (cp is a char_parser)
0018     ///////////////////////////////////////////////////////////////////////////
0019     template <typename Positive>
0020     struct negated_char_parser :
0021         char_parser<negated_char_parser<Positive>>
0022     {
0023         constexpr negated_char_parser(Positive const& positive)
0024           : positive(positive) {}
0025
0026         template <typename CharParam, typename Context>
0027         bool test(CharParam ch, Context const& context) const
0028         {
0029             return !positive.test(ch, context);
0030         }
0031
0032         Positive positive;
0033     };
0034
0035     template <typename Positive>
0036     constexpr negated_char_parser<Positive>
0037     operator~(char_parser<Positive> const& cp)
0038     {
0039         return { cp.derived() };
0040     }
0041
0042     template <typename Positive>
0043     constexpr Positive const&
0044     operator~(negated_char_parser<Positive> const& cp)
0045     {
0046         return cp.positive;
0047     }
0048 }}}
0049
0050 namespace boost { namespace spirit { namespace x3 { namespace traits
0051 {
0052     template <typename Positive, typename Context>
0053     struct attribute_of<x3::negated_char_parser<Positive>, Context>
0054         : attribute_of<Positive, Context> {};
0055
0056     template <typename Positive, typename Context>
0057     struct has_attribute<x3::negated_char_parser<Positive>, Context>
0058         : has_attribute<Positive, Context> {};
0059 }}}}
0060
0061 #endif