text: /*
   *
   * Copyright (c) 2003
   * John Maddock
   *
   * Use, modification and distribution are subject to the 
   * Boost Software License, Version 1.0. (See accompanying file 
   * LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   *
   */
  
   /*
    *   LOCATION:    see http://www.boost.org for most recent version.
    *   FILE         regex_iterator.hpp
    *   VERSION      see <boost/version.hpp>
    *   DESCRIPTION: Provides regex_iterator implementation.
    */
  
  #ifndef BOOST_REGEX_V4_REGEX_ITERATOR_HPP
  #define BOOST_REGEX_V4_REGEX_ITERATOR_HPP
  
  #include <boost/shared_ptr.hpp>
  
  namespace boost{
  
  #ifdef BOOST_MSVC
  #pragma warning(push)
  #pragma warning(disable: 4103)
  #endif
  #ifdef BOOST_HAS_ABI_HEADERS
  #  include BOOST_ABI_PREFIX
  #endif
  #ifdef BOOST_MSVC
  #pragma warning(pop)
  #endif
  
  template <class BidirectionalIterator, 
            class charT,
            class traits>
  class regex_iterator_implementation 
  {
     typedef basic_regex<charT, traits> regex_type;
  
     match_results<BidirectionalIterator> what;  // current match
     BidirectionalIterator                base;  // start of sequence
     BidirectionalIterator                end;   // end of sequence
     const regex_type                     re;   // the expression
     match_flag_type                      flags; // flags for matching
  
  public:
     regex_iterator_implementation(const regex_type* p, BidirectionalIterator last, match_flag_type f)
        : base(), end(last), re(*p), flags(f){}
     bool init(BidirectionalIterator first)
     {
        base = first;
        return regex_search(first, end, what, re, flags);
     }
     bool compare(const regex_iterator_implementation& that)
     {
        if(this == &that) return true;
        return (&re.get_data() == &that.re.get_data()) && (end == that.end) && (flags == that.flags) && (what[0].first == that.what[0].first) && (what[0].second == that.what[0].second);
     }
     const match_results<BidirectionalIterator>& get()
     { return what; }
     bool next()
     {
        //if(what.prefix().first != what[0].second)
        //   flags |= match_prev_avail;
        BidirectionalIterator next_start = what[0].second;
        match_flag_type f(flags);
        if(!what.length())
           f |= regex_constants::match_not_initial_null;
        //if(base != next_start)
        //   f |= regex_constants::match_not_bob;
        bool result = regex_search(next_start, end, what, re, f, base);
        if(result)
           what.set_base(base);
        return result;
     }
  private:
     regex_iterator_implementation& operator=(const regex_iterator_implementation&);
  };
  
  template <class BidirectionalIterator, 
            class charT = BOOST_DEDUCED_TYPENAME re_detail::regex_iterator_traits<BidirectionalIterator>::value_type,
            class traits = regex_traits<charT> >
  class regex_iterator 
  #ifndef BOOST_NO_STD_ITERATOR
     : public std::iterator<
           std::forward_iterator_tag, 
           match_results<BidirectionalIterator>,
           typename re_detail::regex_iterator_traits<BidirectionalIterator>::difference_type,
           const match_results<BidirectionalIterator>*,
           const match_results<BidirectionalIterator>& >         
  #endif
  {
  private:
     typedef regex_iterator_implementation<BidirectionalIterator, charT, traits> impl;
     typedef shared_ptr<impl> pimpl;
  public:
     typedef          basic_regex<charT, traits>                   regex_type;
     typedef          match_results<BidirectionalIterator>                    value_type;
     typedef typename re_detail::regex_iterator_traits<BidirectionalIterator>::difference_type 
                                                                              difference_type;
     typedef          const value_type*                                       pointer;
     typedef          const value_type&                                       reference; 
     typedef          std::forward_iterator_tag                               iterator_category;
     
     regex_iterator(){}
     regex_iterator(BidirectionalIterator a, BidirectionalIterator b, 
                    const regex_type& re, 
                    match_flag_type m = match_default)
                    : pdata(new impl(&re, b, m))
     {
        if(!pdata->init(a))
        {
           pdata.reset();
        }
     }
     regex_iterator(const regex_iterator& that)
        : pdata(that.pdata) {}
     regex_iterator& operator=(const regex_iterator& that)
     {
        pdata = that.pdata;
        return *this;
     }
     bool operator==(const regex_iterator& that)const
     { 
        if((pdata.get() == 0) || (that.pdata.get() == 0))
           return pdata.get() == that.pdata.get();
        return pdata->compare(*(that.pdata.get())); 
     }
     bool operator!=(const regex_iterator& that)const
     { return !(*this == that); }
     const value_type& operator*()const
     { return pdata->get(); }
     const value_type* operator->()const
     { return &(pdata->get()); }
     regex_iterator& operator++()
     {
        cow();
        if(0 == pdata->next())
        {
           pdata.reset();
        }
        return *this;
     }
     regex_iterator operator++(int)
     {
        regex_iterator result(*this);
        ++(*this);
        return result;
     }
  private:
  
     pimpl pdata;
  
     void cow()
     {
        // copy-on-write
        if(pdata.get() && !pdata.unique())
        {
           pdata.reset(new impl(*(pdata.get())));
        }
     }
  };
  
  typedef regex_iterator<const char*> cregex_iterator;
  typedef regex_iterator<std::string::const_iterator> sregex_iterator;
  #ifndef BOOST_NO_WREGEX
  typedef regex_iterator<const wchar_t*> wcregex_iterator;
  typedef regex_iterator<std::wstring::const_iterator> wsregex_iterator;
  #endif
  
  // make_regex_iterator:
  template <class charT, class traits>
  inline regex_iterator<const charT*, charT, traits> make_regex_iterator(const charT* p, const basic_regex<charT, traits>& e, regex_constants::match_flag_type m = regex_constants::match_default)
  {
     return regex_iterator<const charT*, charT, traits>(p, p+traits::length(p), e, m);
  }
  template <class charT, class traits, class ST, class SA>
  inline regex_iterator<typename std::basic_string<charT, ST, SA>::const_iterator, charT, traits> make_regex_iterator(const std::basic_string<charT, ST, SA>& p, const basic_regex<charT, traits>& e, regex_constants::match_flag_type m = regex_constants::match_default)
  {
     return regex_iterator<typename std::basic_string<charT, ST, SA>::const_iterator, charT, traits>(p.begin(), p.end(), e, m);
  }
  
  #ifdef BOOST_MSVC
  #pragma warning(push)
  #pragma warning(disable: 4103)
  #endif
  #ifdef BOOST_HAS_ABI_HEADERS
  #  include BOOST_ABI_SUFFIX
  #endif
  #ifdef BOOST_MSVC
  #pragma warning(pop)
  #endif
  
  } // namespace boost
  
  #endif // BOOST_REGEX_V4_REGEX_ITERATOR_HPP
  
  