Chris@101: /* Copyright 2003-2013 Joaquin M Lopez Munoz.
Chris@16:  * Distributed under the Boost Software License, Version 1.0.
Chris@16:  * (See accompanying file LICENSE_1_0.txt or copy at
Chris@16:  * http://www.boost.org/LICENSE_1_0.txt)
Chris@16:  *
Chris@16:  * See http://www.boost.org/libs/multi_index for library home page.
Chris@16:  */
Chris@16: 
Chris@16: #ifndef BOOST_MULTI_INDEX_DETAIL_DUPLICATES_ITERATOR_HPP
Chris@16: #define BOOST_MULTI_INDEX_DETAIL_DUPLICATES_ITERATOR_HPP
Chris@16: 
Chris@101: #if defined(_MSC_VER)
Chris@16: #pragma once
Chris@16: #endif
Chris@16: 
Chris@16: #include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
Chris@16: #include <cstddef>
Chris@16: #include <iterator>
Chris@16: 
Chris@16: namespace boost{
Chris@16: 
Chris@16: namespace multi_index{
Chris@16: 
Chris@16: namespace detail{
Chris@16: 
Chris@16: /* duplicates_operator is given a range of ordered elements and
Chris@16:  * passes only over those which are duplicated.
Chris@16:  */
Chris@16: 
Chris@16: template<typename Node,typename Predicate>
Chris@16: class duplicates_iterator
Chris@16: {
Chris@16: public:
Chris@16:   typedef typename Node::value_type        value_type;
Chris@16:   typedef std::ptrdiff_t                   difference_type;
Chris@16:   typedef const typename Node::value_type* pointer;
Chris@16:   typedef const typename Node::value_type& reference;
Chris@16:   typedef std::forward_iterator_tag        iterator_category;
Chris@16: 
Chris@16:   duplicates_iterator(Node* node_,Node* end_,Predicate pred_):
Chris@16:     node(node_),begin_chunk(0),end(end_),pred(pred_)
Chris@16:   {
Chris@16:     advance();
Chris@16:   }
Chris@16: 
Chris@16:   duplicates_iterator(Node* end_,Predicate pred_):
Chris@16:     node(end_),begin_chunk(end_),end(end_),pred(pred_)
Chris@16:   {
Chris@16:   }
Chris@16: 
Chris@16:   reference operator*()const
Chris@16:   {
Chris@16:     return node->value();
Chris@16:   }
Chris@16: 
Chris@16:   pointer operator->()const
Chris@16:   {
Chris@16:     return &node->value();
Chris@16:   }
Chris@16: 
Chris@16:   duplicates_iterator& operator++()
Chris@16:   {
Chris@16:     Node::increment(node);
Chris@16:     sync();
Chris@16:     return *this;
Chris@16:   }
Chris@16: 
Chris@16:   duplicates_iterator operator++(int)
Chris@16:   {
Chris@16:     duplicates_iterator tmp(*this);
Chris@16:     ++(*this);
Chris@16:     return tmp;
Chris@16:   }
Chris@16: 
Chris@16:   Node* get_node()const{return node;}
Chris@16: 
Chris@16: private:
Chris@16:   void sync()
Chris@16:   {
Chris@16:     if(node!=end&&pred(begin_chunk->value(),node->value()))advance();
Chris@16:   }
Chris@16: 
Chris@16:   void advance()
Chris@16:   {
Chris@16:     for(Node* node2=node;node!=end;node=node2){
Chris@16:       Node::increment(node2);
Chris@16:       if(node2!=end&&!pred(node->value(),node2->value()))break;
Chris@16:     }
Chris@16:     begin_chunk=node;
Chris@16:   }
Chris@16: 
Chris@16:   Node*     node;
Chris@16:   Node*     begin_chunk;
Chris@16:   Node*     end;
Chris@16:   Predicate pred;
Chris@16: };
Chris@16: 
Chris@16: template<typename Node,typename Predicate>
Chris@16: bool operator==(
Chris@16:   const duplicates_iterator<Node,Predicate>& x,
Chris@16:   const duplicates_iterator<Node,Predicate>& y)
Chris@16: {
Chris@16:   return x.get_node()==y.get_node();
Chris@16: }
Chris@16: 
Chris@16: template<typename Node,typename Predicate>
Chris@16: bool operator!=(
Chris@16:   const duplicates_iterator<Node,Predicate>& x,
Chris@16:   const duplicates_iterator<Node,Predicate>& y)
Chris@16: {
Chris@16:   return !(x==y);
Chris@16: }
Chris@16: 
Chris@16: } /* namespace multi_index::detail */
Chris@16: 
Chris@16: } /* namespace multi_index */
Chris@16: 
Chris@16: } /* namespace boost */
Chris@16: 
Chris@16: #endif