boost/xpressive/detail/core/matcher/attr_matcher.hpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // attr_matcher.hpp
   3 //
   4 //  Copyright 2008 Eric Niebler.
   5 //  Copyright 2008 David Jenkins.
   6 //
   7 //  Distributed under the Boost Software License, Version 1.0. (See
   8 //  accompanying file LICENSE_1_0.txt or copy at
   9 //  http://www.boost.org/LICENSE_1_0.txt)
  10
  11 #ifndef BOOST_XPRESSIVE_DETAIL_CORE_MATCHER_ATTR_MATCHER_HPP_EAN_06_09_2007
  12 #define BOOST_XPRESSIVE_DETAIL_CORE_MATCHER_ATTR_MATCHER_HPP_EAN_06_09_2007
  13
  14 // MS compatible compilers support #pragma once
  15 #if defined(_MSC_VER)
  16 # pragma once
  17 #endif
  18
  19 #include <boost/xpressive/detail/detail_fwd.hpp>
  20 #include <boost/xpressive/detail/core/quant_style.hpp>
  21 #include <boost/xpressive/detail/core/state.hpp>
  22 #include <boost/xpressive/detail/utility/symbols.hpp>
  23
  24 namespace boost { namespace xpressive { namespace detail
  25 {
  26
  27     ///////////////////////////////////////////////////////////////////////////////
  28     // char_translate
  29     //
  30     template<typename Traits, bool ICase>
  31     struct char_translate
  32     {
  33         typedef typename Traits::char_type char_type;
  34         Traits const &traits_;
  35
  36         explicit char_translate(Traits const &tr)
  37           : traits_(tr)
  38         {}
  39
  40         char_type operator ()(char_type ch1) const
  41         {
  42             return this->traits_.translate(ch1);
  43         }
  44     private:
  45         char_translate &operator =(char_translate const &);
  46     };
  47
  48     ///////////////////////////////////////////////////////////////////////////////
  49     // char_translate
  50     //
  51     template<typename Traits>
  52     struct char_translate<Traits, true>
  53     {
  54         typedef typename Traits::char_type char_type;
  55         Traits const &traits_;
  56
  57         explicit char_translate(Traits const &tr)
  58           : traits_(tr)
  59         {}
  60
  61         char_type operator ()(char_type ch1) const
  62         {
  63             return this->traits_.translate_nocase(ch1);
  64         }
  65     private:
  66         char_translate &operator =(char_translate const &);
  67     };
  68
  69     ///////////////////////////////////////////////////////////////////////////////
  70     // attr_matcher
  71     //  Note: the Matcher is a std::map
  72     template<typename Matcher, typename Traits, typename ICase>
  73     struct attr_matcher
  74       : quant_style<quant_none, 0, false>
  75     {
  76         typedef typename Matcher::value_type::second_type const* result_type;
  77
  78         attr_matcher(int slot, Matcher const &matcher, Traits const& tr)
  79           : slot_(slot-1)
  80         {
  81             char_translate<Traits, ICase::value> trans(tr);
  82             this->sym_.load(matcher, trans);
  83         }
  84
  85         template<typename BidiIter, typename Next>
  86         bool match(match_state<BidiIter> &state, Next const &next) const
  87         {
  88             BidiIter tmp = state.cur_;
  89             char_translate<Traits, ICase::value> trans(traits_cast<Traits>(state));
  90             result_type const &result = this->sym_(state.cur_, state.end_, trans);
  91             if(result)
  92             {
  93                 void const *old_slot = state.attr_context_.attr_slots_[this->slot_];
  94                 state.attr_context_.attr_slots_[this->slot_] = &*result;
  95                 if(next.match(state))
  96                 {
  97                     return true;
  98                 }
  99                 state.attr_context_.attr_slots_[this->slot_] = old_slot;
 100             }
 101             state.cur_ = tmp;
 102             return false;
 103         }
 104
 105         int slot_;
 106         boost::xpressive::detail::symbols<Matcher> sym_;
 107     };
 108
 109 }}}
 110
 111 #endif