ceph/src/boost/boost/spirit/home/classic/core/composite/intersection.hpp

   1 /*=============================================================================
   2     Copyright (c) 1998-2003 Joel de Guzman
   3     Copyright (c) 2001 Daniel Nuffer
   4     Copyright (c) 2002 Hartmut Kaiser
   5     http://spirit.sourceforge.net/
   6
   7   Distributed under the Boost Software License, Version 1.0. (See accompanying
   8   file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   9 =============================================================================*/
  10 #if !defined(BOOST_SPIRIT_INTERSECTION_HPP)
  11 #define BOOST_SPIRIT_INTERSECTION_HPP
  12
  13 #include <boost/spirit/home/classic/namespace.hpp>
  14 #include <boost/spirit/home/classic/core/parser.hpp>
  15 #include <boost/spirit/home/classic/core/primitives/primitives.hpp>
  16 #include <boost/spirit/home/classic/core/composite/composite.hpp>
  17 #include <boost/spirit/home/classic/meta/as_parser.hpp>
  18
  19 namespace boost { namespace spirit {
  20
  21 BOOST_SPIRIT_CLASSIC_NAMESPACE_BEGIN
  22
  23     ///////////////////////////////////////////////////////////////////////////
  24     //
  25     //  intersection class
  26     //
  27     //      Handles expressions of the form:
  28     //
  29     //          a & b
  30     //
  31     //      where a and b are parsers. The expression returns a composite
  32     //      parser that matches a and b. One (not both) of the operands may
  33     //      be a literal char, wchar_t or a primitive string char const*,
  34     //      wchar_t const*.
  35     //
  36     //      The expression is short circuit evaluated. b is never touched
  37     //      when a is returns a no-match.
  38     //
  39     ///////////////////////////////////////////////////////////////////////////
  40     struct intersection_parser_gen;
  41
  42     template <typename A, typename B>
  43     struct intersection
  44     :   public binary<A, B, parser<intersection<A, B> > >
  45     {
  46         typedef intersection<A, B>              self_t;
  47         typedef binary_parser_category          parser_category_t;
  48         typedef intersection_parser_gen         parser_generator_t;
  49         typedef binary<A, B, parser<self_t> >   base_t;
  50
  51         intersection(A const& a, B const& b)
  52         : base_t(a, b) {}
  53
  54         template <typename ScannerT>
  55         typename parser_result<self_t, ScannerT>::type
  56         parse(ScannerT const& scan) const
  57         {
  58             typedef typename parser_result<self_t, ScannerT>::type result_t;
  59             typedef typename ScannerT::iterator_t iterator_t;
  60             iterator_t save = scan.first;
  61             if (result_t hl = this->left().parse(scan))
  62             {
  63                 ScannerT bscan(scan.first, scan.first, scan);
  64                 scan.first = save;
  65                 result_t hr = this->right().parse(bscan);
  66                 if (hl.length() == hr.length())
  67                     return hl;
  68             }
  69
  70             return scan.no_match();
  71         }
  72     };
  73
  74     struct intersection_parser_gen
  75     {
  76         template <typename A, typename B>
  77         struct result
  78         {
  79             typedef
  80                 intersection<
  81                     typename as_parser<A>::type
  82                   , typename as_parser<B>::type
  83                 >
  84             type;
  85         };
  86
  87         template <typename A, typename B>
  88         static intersection<
  89             typename as_parser<A>::type
  90           , typename as_parser<B>::type
  91         >
  92         generate(A const& a, B const& b)
  93         {
  94             return intersection<BOOST_DEDUCED_TYPENAME as_parser<A>::type,
  95                 BOOST_DEDUCED_TYPENAME as_parser<B>::type>
  96                     (as_parser<A>::convert(a), as_parser<B>::convert(b));
  97         }
  98     };
  99
 100     template <typename A, typename B>
 101     intersection<A, B>
 102     operator&(parser<A> const& a, parser<B> const& b);
 103
 104     template <typename A>
 105     intersection<A, chlit<char> >
 106     operator&(parser<A> const& a, char b);
 107
 108     template <typename B>
 109     intersection<chlit<char>, B>
 110     operator&(char a, parser<B> const& b);
 111
 112     template <typename A>
 113     intersection<A, strlit<char const*> >
 114     operator&(parser<A> const& a, char const* b);
 115
 116     template <typename B>
 117     intersection<strlit<char const*>, B>
 118     operator&(char const* a, parser<B> const& b);
 119
 120     template <typename A>
 121     intersection<A, chlit<wchar_t> >
 122     operator&(parser<A> const& a, wchar_t b);
 123
 124     template <typename B>
 125     intersection<chlit<wchar_t>, B>
 126     operator&(wchar_t a, parser<B> const& b);
 127
 128     template <typename A>
 129     intersection<A, strlit<wchar_t const*> >
 130     operator&(parser<A> const& a, wchar_t const* b);
 131
 132     template <typename B>
 133     intersection<strlit<wchar_t const*>, B>
 134     operator&(wchar_t const* a, parser<B> const& b);
 135
 136 BOOST_SPIRIT_CLASSIC_NAMESPACE_END
 137
 138 }} // namespace BOOST_SPIRIT_CLASSIC_NS
 139
 140 #endif
 141
 142 #include <boost/spirit/home/classic/core/composite/impl/intersection.ipp>