Add SCons configure checks
[senf.git] / boost_ext / boost / multi_index / detail / duplicates_iterator.hpp
diff --git a/boost_ext/boost/multi_index/detail/duplicates_iterator.hpp b/boost_ext/boost/multi_index/detail/duplicates_iterator.hpp
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+/* Copyright 2003-2006 Joaquín M López Muñoz.
+ * Distributed under 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)
+ *
+ * See http://www.boost.org/libs/multi_index for library home page.
+ */
+
+#ifndef BOOST_MULTI_INDEX_DETAIL_DUPLICATES_ITERATOR_HPP
+#define BOOST_MULTI_INDEX_DETAIL_DUPLICATES_ITERATOR_HPP
+
+#if defined(_MSC_VER)&&(_MSC_VER>=1200)
+#pragma once
+#endif
+
+#include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
+#include <cstddef>
+#include <iterator>
+
+namespace boost{
+
+namespace multi_index{
+
+namespace detail{
+
+/* duplicates_operator is given a range of ordered elements and
+ * passes only over those which are duplicated.
+ */
+
+template<typename Node,typename Predicate>
+class duplicates_iterator
+{
+public:
+  typedef typename Node::value_type        value_type;
+  typedef std::ptrdiff_t                   difference_type;
+  typedef const typename Node::value_type* pointer;
+  typedef const typename Node::value_type& reference;
+  typedef std::forward_iterator_tag        iterator_category;
+
+  duplicates_iterator(Node* node_,Node* end_,Predicate pred_):
+    node(node_),begin_chunk(0),end(end_),pred(pred_)
+  {
+    advance();
+  }
+
+  duplicates_iterator(Node* end_,Predicate pred_):
+    node(end_),begin_chunk(end_),end(end_),pred(pred_)
+  {
+  }
+
+  reference operator*()const
+  {
+    return node->value();
+  }
+
+  pointer operator->()const
+  {
+    return &node->value();
+  }
+
+  duplicates_iterator& operator++()
+  {
+    Node::increment(node);
+    sync();
+    return *this;
+  }
+
+  duplicates_iterator operator++(int)
+  {
+    duplicates_iterator tmp(*this);
+    ++(*this);
+    return tmp;
+  }
+
+  Node* get_node()const{return node;}
+
+private:
+  void sync()
+  {
+    if(node!=end&&pred(begin_chunk->value(),node->value()))advance();
+  }
+
+  void advance()
+  {
+    for(Node* node2=node;node!=end;node=node2){
+      Node::increment(node2);
+      if(node2!=end&&!pred(node->value(),node2->value()))break;
+    }
+    begin_chunk=node;
+  }
+
+  Node*     node;
+  Node*     begin_chunk;
+  Node*     end;
+  Predicate pred;
+};
+
+template<typename Node,typename Predicate>
+bool operator==(
+  const duplicates_iterator<Node,Predicate>& x,
+  const duplicates_iterator<Node,Predicate>& y)
+{
+  return x.get_node()==y.get_node();
+}
+
+template<typename Node,typename Predicate>
+bool operator!=(
+  const duplicates_iterator<Node,Predicate>& x,
+  const duplicates_iterator<Node,Predicate>& y)
+{
+  return !(x==y);
+}
+
+} /* namespace multi_index::detail */
+
+} /* namespace multi_index */
+
+} /* namespace boost */
+
+#endif