ceph/src/boost/libs/xpressive/include/boost/xpressive/detail/core/matcher/alternate_matcher.hpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // alternate_matcher.hpp
   3 //
   4 //  Copyright 2008 Eric Niebler. Distributed under the Boost
   5 //  Software License, Version 1.0. (See accompanying file
   6 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   7
   8 #ifndef BOOST_XPRESSIVE_DETAIL_CORE_MATCHER_ALTERNATE_MATCHER_HPP_EAN_10_04_2005
   9 #define BOOST_XPRESSIVE_DETAIL_CORE_MATCHER_ALTERNATE_MATCHER_HPP_EAN_10_04_2005
  10
  11 // MS compatible compilers support #pragma once
  12 #if defined(_MSC_VER)
  13 # pragma once
  14 #endif
  15
  16 #include <boost/version.hpp>
  17 #if BOOST_VERSION <= 103200
  18 // WORKAROUND for Fusion bug in Boost 1.32
  19 namespace boost { namespace fusion
  20 {
  21     namespace detail { struct iterator_root; }
  22     using detail::iterator_root;
  23 }}
  24 #endif
  25
  26 #include <boost/xpressive/detail/detail_fwd.hpp>
  27 #include <boost/xpressive/detail/core/quant_style.hpp>
  28 #include <boost/xpressive/detail/core/state.hpp>
  29 #include <boost/xpressive/detail/dynamic/matchable.hpp>
  30 #include <boost/xpressive/detail/utility/hash_peek_bitset.hpp>
  31 #include <boost/xpressive/detail/utility/algorithm.hpp>
  32 #include <boost/xpressive/detail/utility/any.hpp>
  33
  34 namespace boost { namespace xpressive { namespace detail
  35 {
  36
  37     ///////////////////////////////////////////////////////////////////////////////
  38     // alt_match_pred
  39     //
  40     template<typename BidiIter, typename Next>
  41     struct alt_match_pred
  42     {
  43         alt_match_pred(match_state<BidiIter> &state)
  44           : state_(&state)
  45         {
  46         }
  47
  48         template<typename Xpr>
  49         bool operator ()(Xpr const &xpr) const
  50         {
  51             return xpr.BOOST_NESTED_TEMPLATE push_match<Next>(*this->state_);
  52         }
  53
  54     private:
  55         match_state<BidiIter> *state_;
  56     };
  57
  58     ///////////////////////////////////////////////////////////////////////////////
  59     // alt_match
  60     //
  61     template<typename BidiIter, typename Next>
  62     inline bool alt_match
  63     (
  64         alternates_vector<BidiIter> const &alts, match_state<BidiIter> &state, Next const &
  65     )
  66     {
  67         return detail::any(alts.begin(), alts.end(), alt_match_pred<BidiIter, Next>(state));
  68     }
  69
  70     template<typename Head, typename Tail, typename BidiIter, typename Next>
  71     inline bool alt_match
  72     (
  73         alternates_list<Head, Tail> const &alts, match_state<BidiIter> &state, Next const &
  74     )
  75     {
  76         return fusion::any(alts, alt_match_pred<BidiIter, Next>(state));
  77     }
  78
  79     ///////////////////////////////////////////////////////////////////////////////
  80     // alternate_matcher
  81     template<typename Alternates, typename Traits>
  82     struct alternate_matcher
  83       : quant_style<
  84             Alternates::width != unknown_width::value && Alternates::pure ? quant_fixed_width : quant_variable_width
  85           , Alternates::width
  86           , Alternates::pure
  87         >
  88     {
  89         typedef Alternates alternates_type;
  90         typedef typename Traits::char_type char_type;
  91
  92         Alternates alternates_;
  93         mutable hash_peek_bitset<char_type> bset_;
  94
  95         explicit alternate_matcher(Alternates const &alternates = Alternates())
  96           : alternates_(alternates)
  97           , bset_()
  98         {
  99         }
 100
 101         template<typename BidiIter, typename Next>
 102         bool match(match_state<BidiIter> &state, Next const &next) const
 103         {
 104             if(!state.eos() && !this->can_match_(*state.cur_, traits_cast<Traits>(state)))
 105             {
 106                 return false;
 107             }
 108
 109             return detail::alt_match(this->alternates_, state, next);
 110         }
 111
 112         detail::width get_width() const
 113         {
 114             // Only called when constructing static regexes, and this is a
 115             // set of same-width alternates where the widths are known at compile
 116             // time, as in: sregex rx = +(_ | 'a' | _n);
 117             BOOST_MPL_ASSERT_RELATION(unknown_width::value, !=, Alternates::width);
 118             return Alternates::width;
 119         }
 120
 121     private:
 122         alternate_matcher &operator =(alternate_matcher const &);
 123
 124         bool can_match_(char_type ch, Traits const &tr) const
 125         {
 126             return this->bset_.test(ch, tr);
 127         }
 128     };
 129
 130 }}}
 131
 132 #endif