comparison DEPENDENCIES/generic/include/boost/intrusive/sgtree.hpp @ 16:2665513ce2d3

Add boost headers

+/////////////////////////////////////////////////////////////////////////////
+//
+// (C) Copyright Ion Gaztanaga 2007-2013
+//
+// 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/intrusive for documentation.
+//
+/////////////////////////////////////////////////////////////////////////////
+//
+// The option that yields to non-floating point 1/sqrt(2) alpha is taken
+// from the scapegoat tree implementation of the PSPP library.
+//
+/////////////////////////////////////////////////////////////////////////////
+
+#ifndef BOOST_INTRUSIVE_SGTREE_HPP
+#define BOOST_INTRUSIVE_SGTREE_HPP
+
+#include <boost/intrusive/detail/config_begin.hpp>
+#include <algorithm>
+#include <cstddef>
+#include <functional>
+#include <iterator>
+#include <utility>
+#include <cmath>
+#include <cstddef>
+#include <boost/intrusive/detail/assert.hpp>
+#include <boost/static_assert.hpp>
+#include <boost/intrusive/intrusive_fwd.hpp>
+#include <boost/intrusive/bs_set_hook.hpp>
+#include <boost/intrusive/bstree.hpp>
+#include <boost/intrusive/detail/tree_node.hpp>
+#include <boost/intrusive/detail/ebo_functor_holder.hpp>
+#include <boost/intrusive/pointer_traits.hpp>
+#include <boost/intrusive/detail/mpl.hpp>
+#include <boost/intrusive/detail/utilities.hpp>
+#include <boost/intrusive/options.hpp>
+#include <boost/intrusive/sgtree_algorithms.hpp>
+#include <boost/intrusive/link_mode.hpp>
+#include <boost/move/move.hpp>
+
+namespace boost {
+namespace intrusive {
+
+/// @cond
+
+namespace detail{
+
+//! Returns floor(log2(n)/log2(sqrt(2))) -> floor(2*log2(n))
+//! Undefined if N is 0.
+//!
+//! This function does not use float point operations.
+inline std::size_t calculate_h_sqrt2 (std::size_t n)
+{
+   std::size_t f_log2 = detail::floor_log2(n);
+   return (2*f_log2) + (n >= detail::sqrt2_pow_2xplus1 (f_log2));
+}
+
+struct h_alpha_sqrt2_t
+{
+   h_alpha_sqrt2_t(void){}
+   std::size_t operator()(std::size_t n) const
+   {  return calculate_h_sqrt2(n);  }
+};
+
+struct alpha_0_75_by_max_size_t
+{
+   alpha_0_75_by_max_size_t(void){}
+
+   std::size_t operator()(std::size_t max_tree_size) const
+   {
+      const std::size_t max_tree_size_limit = ((~std::size_t(0))/std::size_t(3));
+      return max_tree_size > max_tree_size_limit ? max_tree_size/4*3 : max_tree_size*3/4;
+   }
+};
+
+struct h_alpha_t
+{
+   explicit h_alpha_t(float inv_minus_logalpha)
+      :  inv_minus_logalpha_(inv_minus_logalpha)
+   {}
+
+   std::size_t operator()(std::size_t n) const
+   {
+      //Returns floor(log2(1/alpha(n))) ->
+      // floor(log2(n)/log(1/alpha)) ->
+      // floor(log2(n)/(-log2(alpha)))
+      //return static_cast<std::size_t>(std::log(float(n))*inv_minus_logalpha_);
+      return static_cast<std::size_t>(detail::fast_log2(float(n))*inv_minus_logalpha_);
+   }
+
+   private:
+   //Since the function will be repeatedly called
+   //precalculate constant data to avoid repeated
+   //calls to log and division.
+   //This will store 1/(-std::log2(alpha_))
+   float inv_minus_logalpha_;
+};
+
+struct alpha_by_max_size_t
+{
+   explicit alpha_by_max_size_t(float alpha)
+      :  alpha_(alpha)
+   {}
+
+   float operator()(std::size_t max_tree_size) const
+   {  return float(max_tree_size)*alpha_;   }
+
+   private:
+   float alpha_;
+};
+
+template<bool Activate, class SizeType>
+struct alpha_holder
+{
+   typedef boost::intrusive::detail::h_alpha_t           h_alpha_t;
+   typedef boost::intrusive::detail::alpha_by_max_size_t multiply_by_alpha_t;
+
+   alpha_holder() : max_tree_size_(0)
+   {  set_alpha(0.7f);   }
+
+   float get_alpha() const
+   {  return alpha_;  }
+
+   void set_alpha(float alpha)
+   {
+      alpha_ = alpha;
+      inv_minus_logalpha_ = 1/(-detail::fast_log2(alpha));
+   }
+
+   h_alpha_t get_h_alpha_t() const
+   {  return h_alpha_t(/*alpha_, */inv_minus_logalpha_);  }
+
+   multiply_by_alpha_t get_multiply_by_alpha_t() const
+   {  return multiply_by_alpha_t(alpha_);  }
+
+   protected:
+   float alpha_;
+   float inv_minus_logalpha_;
+   SizeType max_tree_size_;
+};
+
+template<class SizeType>
+struct alpha_holder<false, SizeType>
+{
+   //This specialization uses alpha = 1/sqrt(2)
+   //without using floating point operations
+   //Downside: alpha CAN't be changed.
+   typedef boost::intrusive::detail::h_alpha_sqrt2_t           h_alpha_t;
+   typedef boost::intrusive::detail::alpha_0_75_by_max_size_t  multiply_by_alpha_t;
+
+   float get_alpha() const
+   {  return 0.70710677f;  }
+
+   void set_alpha(float)
+   {  //alpha CAN't be changed.
+      BOOST_INTRUSIVE_INVARIANT_ASSERT(0);
+   }
+
+   h_alpha_t get_h_alpha_t() const
+   {  return h_alpha_t();  }
+
+   multiply_by_alpha_t get_multiply_by_alpha_t() const
+   {  return multiply_by_alpha_t();  }
+
+   SizeType max_tree_size_;
+};
+
+}  //namespace detail{
+
+struct sgtree_defaults
+{
+   typedef detail::default_bstree_hook proto_value_traits;
+   static const bool constant_time_size = true;
+   typedef std::size_t size_type;
+   typedef void compare;
+   static const bool floating_point = true;
+};
+
+/// @endcond
+
+//! The class template sgtree is an intrusive scapegoat tree container, that
+//! is used to construct intrusive sg_set and sg_multiset containers.
+//! The no-throw guarantee holds only, if the value_compare object
+//! doesn't throw.
+//!
+//! The template parameter \c T is the type to be managed by the container.
+//! The user can specify additional options and if no options are provided
+//! default options are used.
+//!
+//! The container supports the following options:
+//! \c base_hook<>/member_hook<>/value_traits<>,
+//! \c floating_point<>, \c size_type<> and
+//! \c compare<>.
+#if defined(BOOST_INTRUSIVE_DOXYGEN_INVOKED)
+template<class T, class ...Options>
+#else
+template<class ValueTraits, class VoidOrKeyComp, class SizeType, bool FloatingPoint>
+#endif
+class sgtree_impl
+   /// @cond
+   :  public bstree_impl<ValueTraits, VoidOrKeyComp, SizeType, true, SgTreeAlgorithms>
+   ,  public detail::alpha_holder<FloatingPoint, SizeType>
+   /// @endcond
+{
+   public:
+   typedef ValueTraits                                               value_traits;
+   /// @cond
+   typedef bstree_impl< ValueTraits, VoidOrKeyComp, SizeType
+                      , true, SgTreeAlgorithms>                      tree_type;
+   typedef tree_type                                                 implementation_defined;
+   typedef typename tree_type::real_value_traits                     real_value_traits;
+
+   /// @endcond
+
+   typedef typename implementation_defined::pointer                  pointer;
+   typedef typename implementation_defined::const_pointer            const_pointer;
+   typedef typename implementation_defined::value_type               value_type;
+   typedef typename implementation_defined::key_type                 key_type;
+   typedef typename implementation_defined::reference                reference;
+   typedef typename implementation_defined::const_reference          const_reference;
+   typedef typename implementation_defined::difference_type          difference_type;
+   typedef typename implementation_defined::size_type                size_type;
+   typedef typename implementation_defined::value_compare            value_compare;
+   typedef typename implementation_defined::key_compare              key_compare;
+   typedef typename implementation_defined::iterator                 iterator;
+   typedef typename implementation_defined::const_iterator           const_iterator;
+   typedef typename implementation_defined::reverse_iterator         reverse_iterator;
+   typedef typename implementation_defined::const_reverse_iterator   const_reverse_iterator;
+   typedef typename implementation_defined::node_traits              node_traits;
+   typedef typename implementation_defined::node                     node;
+   typedef typename implementation_defined::node_ptr                 node_ptr;
+   typedef typename implementation_defined::const_node_ptr           const_node_ptr;
+   typedef BOOST_INTRUSIVE_IMPDEF(sgtree_algorithms<node_traits>)    node_algorithms;
+
+   static const bool constant_time_size      = implementation_defined::constant_time_size;
+   static const bool floating_point          = FloatingPoint;
+   static const bool stateful_value_traits   = implementation_defined::stateful_value_traits;
+
+   /// @cond
+   private:
+
+   //noncopyable
+   typedef detail::alpha_holder<FloatingPoint, SizeType>    alpha_traits;
+   typedef typename alpha_traits::h_alpha_t                 h_alpha_t;
+   typedef typename alpha_traits::multiply_by_alpha_t       multiply_by_alpha_t;
+
+   BOOST_MOVABLE_BUT_NOT_COPYABLE(sgtree_impl)
+   BOOST_STATIC_ASSERT(((int)real_value_traits::link_mode != (int)auto_unlink));
+
+   enum { safemode_or_autounlink  =
+            (int)real_value_traits::link_mode == (int)auto_unlink   ||
+            (int)real_value_traits::link_mode == (int)safe_link     };
+
+   /// @endcond
+
+   public:
+
+   typedef BOOST_INTRUSIVE_IMPDEF(typename node_algorithms::insert_commit_data) insert_commit_data;
+
+   //! @copydoc ::boost::intrusive::bstree::bstree(const value_compare &,const value_traits &)
+   explicit sgtree_impl( const value_compare &cmp = value_compare()
+                       , const value_traits &v_traits = value_traits())
+      :  tree_type(cmp, v_traits)
+   {}
+
+   //! @copydoc ::boost::intrusive::bstree::bstree(bool,Iterator,Iterator,const value_compare &,const value_traits &)
+   template<class Iterator>
+   sgtree_impl( bool unique, Iterator b, Iterator e
+              , const value_compare &cmp     = value_compare()
+              , const value_traits &v_traits = value_traits())
+      : tree_type(cmp, v_traits)
+   {
+      if(unique)
+         this->insert_unique(b, e);
+      else
+         this->insert_equal(b, e);
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::bstree(bstree &&)
+   sgtree_impl(BOOST_RV_REF(sgtree_impl) x)
+      :  tree_type(::boost::move(static_cast<tree_type&>(x))), alpha_traits(x.get_alpha_traits())
+   {  std::swap(this->get_alpha_traits(), x.get_alpha_traits());   }
+
+   //! @copydoc ::boost::intrusive::bstree::operator=(bstree &&)
+   sgtree_impl& operator=(BOOST_RV_REF(sgtree_impl) x)
+   {
+      this->get_alpha_traits() = x.get_alpha_traits();
+      return static_cast<sgtree_impl&>(tree_type::operator=(::boost::move(static_cast<tree_type&>(x))));
+   }
+
+   /// @cond
+   private:
+
+   const alpha_traits &get_alpha_traits() const
+   {  return *this;  }
+
+   alpha_traits &get_alpha_traits()
+   {  return *this;  }
+
+   h_alpha_t get_h_alpha_func() const
+   {  return this->get_alpha_traits().get_h_alpha_t();  }
+
+   multiply_by_alpha_t get_alpha_by_max_size_func() const
+   {  return this->get_alpha_traits().get_multiply_by_alpha_t(); }
+
+   /// @endcond
+
+   public:
+
+   #ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED
+   //! @copydoc ::boost::intrusive::bstree::~bstree()
+   ~sgtree_impl();
+
+   //! @copydoc ::boost::intrusive::bstree::begin()
+   iterator begin();
+
+   //! @copydoc ::boost::intrusive::bstree::begin()const
+   const_iterator begin() const;
+
+   //! @copydoc ::boost::intrusive::bstree::cbegin()const
+   const_iterator cbegin() const;
+
+   //! @copydoc ::boost::intrusive::bstree::end()
+   iterator end();
+
+   //! @copydoc ::boost::intrusive::bstree::end()const
+   const_iterator end() const;
+
+   //! @copydoc ::boost::intrusive::bstree::cend()const
+   const_iterator cend() const;
+
+   //! @copydoc ::boost::intrusive::bstree::rbegin()
+   reverse_iterator rbegin();
+
+   //! @copydoc ::boost::intrusive::bstree::rbegin()const
+   const_reverse_iterator rbegin() const;
+
+   //! @copydoc ::boost::intrusive::bstree::crbegin()const
+   const_reverse_iterator crbegin() const;
+
+   //! @copydoc ::boost::intrusive::bstree::rend()
+   reverse_iterator rend();
+
+   //! @copydoc ::boost::intrusive::bstree::rend()const
+   const_reverse_iterator rend() const;
+
+   //! @copydoc ::boost::intrusive::bstree::crend()const
+   const_reverse_iterator crend() const;
+
+   //! @copydoc ::boost::intrusive::bstree::container_from_end_iterator(iterator)
+   static sgtree_impl &container_from_end_iterator(iterator end_iterator);
+
+   //! @copydoc ::boost::intrusive::bstree::container_from_end_iterator(const_iterator)
+   static const sgtree_impl &container_from_end_iterator(const_iterator end_iterator);
+
+   //! @copydoc ::boost::intrusive::bstree::container_from_iterator(iterator)
+   static sgtree_impl &container_from_iterator(iterator it);
+
+   //! @copydoc ::boost::intrusive::bstree::container_from_iterator(const_iterator)
+   static const sgtree_impl &container_from_iterator(const_iterator it);
+
+   //! @copydoc ::boost::intrusive::bstree::key_comp()const
+   key_compare key_comp() const;
+
+   //! @copydoc ::boost::intrusive::bstree::value_comp()const
+   value_compare value_comp() const;
+
+   //! @copydoc ::boost::intrusive::bstree::empty()const
+   bool empty() const;
+
+   //! @copydoc ::boost::intrusive::bstree::size()const
+   size_type size() const;
+
+   #endif   //#ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED
+
+   //! @copydoc ::boost::intrusive::bstree::swap
+   void swap(sgtree_impl& other)
+   {
+      //This can throw
+      using std::swap;
+      this->tree_type::swap(static_cast<tree_type&>(other));
+      swap(this->get_alpha_traits(), other.get_alpha_traits());
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::clone_from
+   //! Additional notes: it also copies the alpha factor from the source container.
+   template <class Cloner, class Disposer>
+   void clone_from(const sgtree_impl &src, Cloner cloner, Disposer disposer)
+   {
+      this->tree_type::clone_from(src, cloner, disposer);
+      this->get_alpha_traits() = src.get_alpha_traits();
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::insert_equal(reference)
+   iterator insert_equal(reference value)
+   {
+      detail::key_nodeptr_comp<value_compare, real_value_traits>
+         key_node_comp(this->value_comp(), &this->get_real_value_traits());
+      node_ptr to_insert(this->get_real_value_traits().to_node_ptr(value));
+      if(safemode_or_autounlink)
+         BOOST_INTRUSIVE_SAFE_HOOK_DEFAULT_ASSERT(node_algorithms::unique(to_insert));
+      std::size_t max_tree_size = (std::size_t)this->max_tree_size_;
+      node_ptr p = node_algorithms::insert_equal_upper_bound
+         (this->tree_type::header_ptr(), to_insert, key_node_comp
+         , (size_type)this->size(), this->get_h_alpha_func(), max_tree_size);
+      this->tree_type::sz_traits().increment();
+      this->max_tree_size_ = (size_type)max_tree_size;
+      return iterator(p, this->real_value_traits_ptr());
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::insert_equal(const_iterator,reference)
+   iterator insert_equal(const_iterator hint, reference value)
+   {
+      detail::key_nodeptr_comp<value_compare, real_value_traits>
+         key_node_comp(this->value_comp(), &this->get_real_value_traits());
+      node_ptr to_insert(this->get_real_value_traits().to_node_ptr(value));
+      if(safemode_or_autounlink)
+         BOOST_INTRUSIVE_SAFE_HOOK_DEFAULT_ASSERT(node_algorithms::unique(to_insert));
+      std::size_t max_tree_size = (std::size_t)this->max_tree_size_;
+      node_ptr p = node_algorithms::insert_equal
+         (this->tree_type::header_ptr(), hint.pointed_node(), to_insert, key_node_comp
+         , (std::size_t)this->size(), this->get_h_alpha_func(), max_tree_size);
+      this->tree_type::sz_traits().increment();
+      this->max_tree_size_ = (size_type)max_tree_size;
+      return iterator(p, this->real_value_traits_ptr());
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::insert_equal(Iterator,Iterator)
+   template<class Iterator>
+   void insert_equal(Iterator b, Iterator e)
+   {
+      iterator iend(this->end());
+      for (; b != e; ++b)
+         this->insert_equal(iend, *b);
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::insert_unique(reference)
+   std::pair<iterator, bool> insert_unique(reference value)
+   {
+      insert_commit_data commit_data;
+      std::pair<iterator, bool> ret = insert_unique_check(value, this->value_comp(), commit_data);
+      if(!ret.second)
+         return ret;
+      return std::pair<iterator, bool> (insert_unique_commit(value, commit_data), true);
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::insert_unique(const_iterator,reference)
+   iterator insert_unique(const_iterator hint, reference value)
+   {
+      insert_commit_data commit_data;
+      std::pair<iterator, bool> ret = insert_unique_check(hint, value, this->value_comp(), commit_data);
+      if(!ret.second)
+         return ret.first;
+      return insert_unique_commit(value, commit_data);
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::insert_unique_check(const KeyType&,KeyValueCompare,insert_commit_data&)
+   template<class KeyType, class KeyValueCompare>
+   std::pair<iterator, bool> insert_unique_check
+      (const KeyType &key, KeyValueCompare key_value_comp, insert_commit_data &commit_data)
+   {
+      detail::key_nodeptr_comp<KeyValueCompare, real_value_traits>
+         comp(key_value_comp, &this->get_real_value_traits());
+      std::pair<node_ptr, bool> ret =
+         (node_algorithms::insert_unique_check
+            (this->tree_type::header_ptr(), key, comp, commit_data));
+      return std::pair<iterator, bool>(iterator(ret.first, this->real_value_traits_ptr()), ret.second);
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::insert_unique_check(const_iterator,const KeyType&,KeyValueCompare,insert_commit_data&)
+   template<class KeyType, class KeyValueCompare>
+   std::pair<iterator, bool> insert_unique_check
+      (const_iterator hint, const KeyType &key
+      ,KeyValueCompare key_value_comp, insert_commit_data &commit_data)
+   {
+      detail::key_nodeptr_comp<KeyValueCompare, real_value_traits>
+         comp(key_value_comp, &this->get_real_value_traits());
+      std::pair<node_ptr, bool> ret =
+         (node_algorithms::insert_unique_check
+            (this->tree_type::header_ptr(), hint.pointed_node(), key, comp, commit_data));
+      return std::pair<iterator, bool>(iterator(ret.first, this->real_value_traits_ptr()), ret.second);
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::insert_unique_commit
+   iterator insert_unique_commit(reference value, const insert_commit_data &commit_data)
+   {
+      node_ptr to_insert(this->get_real_value_traits().to_node_ptr(value));
+      if(safemode_or_autounlink)
+         BOOST_INTRUSIVE_SAFE_HOOK_DEFAULT_ASSERT(node_algorithms::unique(to_insert));
+      std::size_t max_tree_size = (std::size_t)this->max_tree_size_;
+      node_algorithms::insert_unique_commit
+         ( this->tree_type::header_ptr(), to_insert, commit_data
+         , (std::size_t)this->size(), this->get_h_alpha_func(), max_tree_size);
+      this->tree_type::sz_traits().increment();
+      this->max_tree_size_ = (size_type)max_tree_size;
+      return iterator(to_insert, this->real_value_traits_ptr());
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::insert_unique(Iterator,Iterator)
+   template<class Iterator>
+   void insert_unique(Iterator b, Iterator e)
+   {
+      if(this->empty()){
+         iterator iend(this->end());
+         for (; b != e; ++b)
+            this->insert_unique(iend, *b);
+      }
+      else{
+         for (; b != e; ++b)
+            this->insert_unique(*b);
+      }
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::insert_before
+   iterator insert_before(const_iterator pos, reference value)
+   {
+      node_ptr to_insert(this->get_real_value_traits().to_node_ptr(value));
+      if(safemode_or_autounlink)
+         BOOST_INTRUSIVE_SAFE_HOOK_DEFAULT_ASSERT(node_algorithms::unique(to_insert));
+      std::size_t max_tree_size = (std::size_t)this->max_tree_size_;
+      node_ptr p = node_algorithms::insert_before
+         ( this->tree_type::header_ptr(), pos.pointed_node(), to_insert
+         , (size_type)this->size(), this->get_h_alpha_func(), max_tree_size);
+      this->tree_type::sz_traits().increment();
+      this->max_tree_size_ = (size_type)max_tree_size;
+      return iterator(p, this->real_value_traits_ptr());
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::push_back
+   void push_back(reference value)
+   {
+      node_ptr to_insert(this->get_real_value_traits().to_node_ptr(value));
+      if(safemode_or_autounlink)
+         BOOST_INTRUSIVE_SAFE_HOOK_DEFAULT_ASSERT(node_algorithms::unique(to_insert));
+      std::size_t max_tree_size = (std::size_t)this->max_tree_size_;
+      node_algorithms::push_back
+         ( this->tree_type::header_ptr(), to_insert
+         , (size_type)this->size(), this->get_h_alpha_func(), max_tree_size);
+      this->tree_type::sz_traits().increment();
+      this->max_tree_size_ = (size_type)max_tree_size;
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::push_front
+   void push_front(reference value)
+   {
+      node_ptr to_insert(this->get_real_value_traits().to_node_ptr(value));
+      if(safemode_or_autounlink)
+         BOOST_INTRUSIVE_SAFE_HOOK_DEFAULT_ASSERT(node_algorithms::unique(to_insert));
+      std::size_t max_tree_size = (std::size_t)this->max_tree_size_;
+      node_algorithms::push_front
+         ( this->tree_type::header_ptr(), to_insert
+         , (size_type)this->size(), this->get_h_alpha_func(), max_tree_size);
+      this->tree_type::sz_traits().increment();
+      this->max_tree_size_ = (size_type)max_tree_size;
+   }
+
+
+   //! @copydoc ::boost::intrusive::bstree::erase(const_iterator)
+   iterator erase(const_iterator i)
+   {
+      const_iterator ret(i);
+      ++ret;
+      node_ptr to_erase(i.pointed_node());
+      if(safemode_or_autounlink)
+         BOOST_INTRUSIVE_SAFE_HOOK_DEFAULT_ASSERT(!node_algorithms::unique(to_erase));
+      std::size_t max_tree_size = this->max_tree_size_;
+      node_algorithms::erase
+         ( this->tree_type::header_ptr(), to_erase, (std::size_t)this->size()
+         , max_tree_size, this->get_alpha_by_max_size_func());
+      this->max_tree_size_ = (size_type)max_tree_size;
+      this->tree_type::sz_traits().decrement();
+      if(safemode_or_autounlink)
+         node_algorithms::init(to_erase);
+      return ret.unconst();
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::erase(const_iterator,const_iterator)
+   iterator erase(const_iterator b, const_iterator e)
+   {  size_type n;   return private_erase(b, e, n);   }
+
+   //! @copydoc ::boost::intrusive::bstree::erase(const_reference)
+   size_type erase(const_reference value)
+   {  return this->erase(value, this->value_comp());   }
+
+   //! @copydoc ::boost::intrusive::bstree::erase(const KeyType&,KeyValueCompare)
+   template<class KeyType, class KeyValueCompare>
+   size_type erase(const KeyType& key, KeyValueCompare comp
+                  /// @cond
+                  , typename detail::enable_if_c<!detail::is_convertible<KeyValueCompare, const_iterator>::value >::type * = 0
+                  /// @endcond
+                  )
+   {
+      std::pair<iterator,iterator> p = this->equal_range(key, comp);
+      size_type n;
+      private_erase(p.first, p.second, n);
+      return n;
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::erase_and_dispose(const_iterator,Disposer)
+   template<class Disposer>
+   iterator erase_and_dispose(const_iterator i, Disposer disposer)
+   {
+      node_ptr to_erase(i.pointed_node());
+      iterator ret(this->erase(i));
+      disposer(this->get_real_value_traits().to_value_ptr(to_erase));
+      return ret;
+   }
+
+   #if !defined(BOOST_INTRUSIVE_DOXYGEN_INVOKED)
+   template<class Disposer>
+   iterator erase_and_dispose(iterator i, Disposer disposer)
+   {  return this->erase_and_dispose(const_iterator(i), disposer);   }
+   #endif
+
+   //! @copydoc ::boost::intrusive::bstree::erase_and_dispose(const_iterator,const_iterator,Disposer)
+   template<class Disposer>
+   iterator erase_and_dispose(const_iterator b, const_iterator e, Disposer disposer)
+   {  size_type n;   return private_erase(b, e, n, disposer);   }
+
+   //! @copydoc ::boost::intrusive::bstree::erase_and_dispose(const_reference, Disposer)
+   template<class Disposer>
+   size_type erase_and_dispose(const_reference value, Disposer disposer)
+   {
+      std::pair<iterator,iterator> p = this->equal_range(value);
+      size_type n;
+      private_erase(p.first, p.second, n, disposer);
+      return n;
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::erase_and_dispose(const KeyType&,KeyValueCompare,Disposer)
+   template<class KeyType, class KeyValueCompare, class Disposer>
+   size_type erase_and_dispose(const KeyType& key, KeyValueCompare comp, Disposer disposer
+                  /// @cond
+                  , typename detail::enable_if_c<!detail::is_convertible<KeyValueCompare, const_iterator>::value >::type * = 0
+                  /// @endcond
+                  )
+   {
+      std::pair<iterator,iterator> p = this->equal_range(key, comp);
+      size_type n;
+      private_erase(p.first, p.second, n, disposer);
+      return n;
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::clear
+   void clear()
+   {
+      tree_type::clear();
+      this->max_tree_size_ = 0;
+   }
+
+   //! @copydoc ::boost::intrusive::bstree::clear_and_dispose
+   template<class Disposer>
+   void clear_and_dispose(Disposer disposer)
+   {
+      tree_type::clear_and_dispose(disposer);
+      this->max_tree_size_ = 0;
+   }
+
+   #ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED
+   //! @copydoc ::boost::intrusive::bstree::count(const_reference)const
+   size_type count(const_reference value) const;
+
+   //! @copydoc ::boost::intrusive::bstree::count(const KeyType&,KeyValueCompare)const
+   template<class KeyType, class KeyValueCompare>
+   size_type count(const KeyType& key, KeyValueCompare comp) const;
+   
+   //! @copydoc ::boost::intrusive::bstree::lower_bound(const_reference)
+   iterator lower_bound(const_reference value);
+   
+   //! @copydoc ::boost::intrusive::bstree::lower_bound(const KeyType&,KeyValueCompare)
+   template<class KeyType, class KeyValueCompare>
+   iterator lower_bound(const KeyType& key, KeyValueCompare comp);
+
+   //! @copydoc ::boost::intrusive::bstree::lower_bound(const_reference)const
+   const_iterator lower_bound(const_reference value) const;
+
+   //! @copydoc ::boost::intrusive::bstree::lower_bound(const KeyType&,KeyValueCompare)const
+   template<class KeyType, class KeyValueCompare>
+   const_iterator lower_bound(const KeyType& key, KeyValueCompare comp) const;
+
+   //! @copydoc ::boost::intrusive::bstree::upper_bound(const_reference)
+   iterator upper_bound(const_reference value);
+
+   //! @copydoc ::boost::intrusive::bstree::upper_bound(const KeyType&,KeyValueCompare)
+   template<class KeyType, class KeyValueCompare>
+   iterator upper_bound(const KeyType& key, KeyValueCompare comp);
+
+   //! @copydoc ::boost::intrusive::bstree::upper_bound(const_reference)const
+   const_iterator upper_bound(const_reference value) const;
+
+   //! @copydoc ::boost::intrusive::bstree::upper_bound(const KeyType&,KeyValueCompare)const
+   template<class KeyType, class KeyValueCompare>
+   const_iterator upper_bound(const KeyType& key, KeyValueCompare comp) const;
+
+   //! @copydoc ::boost::intrusive::bstree::find(const_reference)
+   iterator find(const_reference value);
+
+   //! @copydoc ::boost::intrusive::bstree::find(const KeyType&,KeyValueCompare)
+   template<class KeyType, class KeyValueCompare>
+   iterator find(const KeyType& key, KeyValueCompare comp);
+
+   //! @copydoc ::boost::intrusive::bstree::find(const_reference)const
+   const_iterator find(const_reference value) const;
+
+   //! @copydoc ::boost::intrusive::bstree::find(const KeyType&,KeyValueCompare)const
+   template<class KeyType, class KeyValueCompare>
+   const_iterator find(const KeyType& key, KeyValueCompare comp) const;
+
+   //! @copydoc ::boost::intrusive::bstree::equal_range(const_reference)
+   std::pair<iterator,iterator> equal_range(const_reference value);
+
+   //! @copydoc ::boost::intrusive::bstree::equal_range(const KeyType&,KeyValueCompare)
+   template<class KeyType, class KeyValueCompare>
+   std::pair<iterator,iterator> equal_range(const KeyType& key, KeyValueCompare comp);
+
+   //! @copydoc ::boost::intrusive::bstree::equal_range(const_reference)const
+   std::pair<const_iterator, const_iterator>
+      equal_range(const_reference value) const;
+
+   //! @copydoc ::boost::intrusive::bstree::equal_range(const KeyType&,KeyValueCompare)const
+   template<class KeyType, class KeyValueCompare>
+   std::pair<const_iterator, const_iterator>
+      equal_range(const KeyType& key, KeyValueCompare comp) const;
+
+   //! @copydoc ::boost::intrusive::bstree::bounded_range(const_reference,const_reference,bool,bool)
+   std::pair<iterator,iterator> bounded_range
+      (const_reference lower_value, const_reference upper_value, bool left_closed, bool right_closed);
+
+   //! @copydoc ::boost::intrusive::bstree::bounded_range(const KeyType&,const KeyType&,KeyValueCompare,bool,bool)
+   template<class KeyType, class KeyValueCompare>
+   std::pair<iterator,iterator> bounded_range
+      (const KeyType& lower_key, const KeyType& upper_key, KeyValueCompare comp, bool left_closed, bool right_closed);
+
+   //! @copydoc ::boost::intrusive::bstree::bounded_range(const_reference,const_reference,bool,bool)const
+   std::pair<const_iterator, const_iterator>
+      bounded_range(const_reference lower_value, const_reference upper_value, bool left_closed, bool right_closed) const;
+
+   //! @copydoc ::boost::intrusive::bstree::bounded_range(const KeyType&,const KeyType&,KeyValueCompare,bool,bool)const
+   template<class KeyType, class KeyValueCompare>
+   std::pair<const_iterator, const_iterator> bounded_range
+         (const KeyType& lower_key, const KeyType& upper_key, KeyValueCompare comp, bool left_closed, bool right_closed) const;
+
+   //! @copydoc ::boost::intrusive::bstree::s_iterator_to(reference)
+   static iterator s_iterator_to(reference value);
+
+   //! @copydoc ::boost::intrusive::bstree::s_iterator_to(const_reference)
+   static const_iterator s_iterator_to(const_reference value);
+
+   //! @copydoc ::boost::intrusive::bstree::iterator_to(reference)
+   iterator iterator_to(reference value);
+
+   //! @copydoc ::boost::intrusive::bstree::iterator_to(const_reference)const
+   const_iterator iterator_to(const_reference value) const;
+
+   //! @copydoc ::boost::intrusive::bstree::init_node(reference)
+   static void init_node(reference value);
+
+   //! @copydoc ::boost::intrusive::bstree::unlink_leftmost_without_rebalance
+   pointer unlink_leftmost_without_rebalance();
+
+   //! @copydoc ::boost::intrusive::bstree::replace_node
+   void replace_node(iterator replace_this, reference with_this);
+
+   //! @copydoc ::boost::intrusive::bstree::remove_node
+   void remove_node(reference value);
+
+   //! @copydoc ::boost::intrusive::bstree::rebalance
+   void rebalance();
+
+   //! @copydoc ::boost::intrusive::bstree::rebalance_subtree
+   iterator rebalance_subtree(iterator root);
+
+   #endif   //#ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED
+
+   //! <b>Returns</b>: The balance factor (alpha) used in this tree
+   //!
+   //! <b>Throws</b>: Nothing.
+   //!
+   //! <b>Complexity</b>: Constant.
+   float balance_factor() const
+   {  return this->get_alpha_traits().get_alpha(); }
+
+   //! <b>Requires</b>: new_alpha must be a value between 0.5 and 1.0
+   //!
+   //! <b>Effects</b>: Establishes a new balance factor (alpha) and rebalances
+   //!   the tree if the new balance factor is stricter (less) than the old factor.
+   //!
+   //! <b>Throws</b>: Nothing.
+   //!
+   //! <b>Complexity</b>: Linear to the elements in the subtree.
+   void balance_factor(float new_alpha)
+   {
+      BOOST_INTRUSIVE_INVARIANT_ASSERT((new_alpha > 0.5f && new_alpha < 1.0f));
+      if(new_alpha < 0.5f && new_alpha >= 1.0f)  return;
+
+      //The alpha factor CAN't be changed if the fixed, floating operation-less
+      //1/sqrt(2) alpha factor option is activated
+      BOOST_STATIC_ASSERT((floating_point));
+      float old_alpha = this->get_alpha_traits().get_alpha();
+      this->get_alpha_traits().set_alpha(new_alpha);
+
+      if(new_alpha < old_alpha){
+         this->max_tree_size_ = this->size();
+         this->rebalance();
+      }
+   }
+
+   /// @cond
+   private:
+   template<class Disposer>
+   iterator private_erase(const_iterator b, const_iterator e, size_type &n, Disposer disposer)
+   {
+      for(n = 0; b != e; ++n)
+        this->erase_and_dispose(b++, disposer);
+      return b.unconst();
+   }
+
+   iterator private_erase(const_iterator b, const_iterator e, size_type &n)
+   {
+      for(n = 0; b != e; ++n)
+        this->erase(b++);
+      return b.unconst();
+   }
+   /// @endcond
+};
+
+#if defined(BOOST_INTRUSIVE_DOXYGEN_INVOKED)
+
+template<class T, class ...Options>
+bool operator< (const sgtree_impl<T, Options...> &x, const sgtree_impl<T, Options...> &y);
+
+template<class T, class ...Options>
+bool operator==(const sgtree_impl<T, Options...> &x, const sgtree_impl<T, Options...> &y);
+
+template<class T, class ...Options>
+bool operator!= (const sgtree_impl<T, Options...> &x, const sgtree_impl<T, Options...> &y);
+
+template<class T, class ...Options>
+bool operator>(const sgtree_impl<T, Options...> &x, const sgtree_impl<T, Options...> &y);
+
+template<class T, class ...Options>
+bool operator<=(const sgtree_impl<T, Options...> &x, const sgtree_impl<T, Options...> &y);
+
+template<class T, class ...Options>
+bool operator>=(const sgtree_impl<T, Options...> &x, const sgtree_impl<T, Options...> &y);
+
+template<class T, class ...Options>
+void swap(sgtree_impl<T, Options...> &x, sgtree_impl<T, Options...> &y);
+
+#endif   //#if defined(BOOST_INTRUSIVE_DOXYGEN_INVOKED)
+
+//! Helper metafunction to define a \c sgtree that yields to the same type when the
+//! same options (either explicitly or implicitly) are used.
+#if defined(BOOST_INTRUSIVE_DOXYGEN_INVOKED) || defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
+template<class T, class ...Options>
+#else
+template<class T, class O1 = void, class O2 = void
+                , class O3 = void, class O4 = void>
+#endif
+struct make_sgtree
+{
+   /// @cond
+   typedef typename pack_options
+      < sgtree_defaults,
+      #if !defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
+      O1, O2, O3, O4
+      #else
+      Options...
+      #endif
+      >::type packed_options;
+
+   typedef typename detail::get_value_traits
+      <T, typename packed_options::proto_value_traits>::type value_traits;
+
+   typedef sgtree_impl
+         < value_traits
+         , typename packed_options::compare
+         , typename packed_options::size_type
+         , packed_options::floating_point
+         > implementation_defined;
+   /// @endcond
+   typedef implementation_defined type;
+};
+
+
+#ifndef BOOST_INTRUSIVE_DOXYGEN_INVOKED
+
+#if !defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
+template<class T, class O1, class O2, class O3, class O4>
+#else
+template<class T, class ...Options>
+#endif
+class sgtree
+   :  public make_sgtree<T,
+      #if !defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
+      O1, O2, O3, O4
+      #else
+      Options...
+      #endif
+      >::type
+{
+   typedef typename make_sgtree
+      <T,
+      #if !defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
+      O1, O2, O3, O4
+      #else
+      Options...
+      #endif
+      >::type   Base;
+   BOOST_MOVABLE_BUT_NOT_COPYABLE(sgtree)
+
+   public:
+   typedef typename Base::value_compare      value_compare;
+   typedef typename Base::value_traits       value_traits;
+   typedef typename Base::real_value_traits  real_value_traits;
+   typedef typename Base::iterator           iterator;
+   typedef typename Base::const_iterator     const_iterator;
+   typedef typename Base::reverse_iterator           reverse_iterator;
+   typedef typename Base::const_reverse_iterator     const_reverse_iterator;
+
+   //Assert if passed value traits are compatible with the type
+   BOOST_STATIC_ASSERT((detail::is_same<typename real_value_traits::value_type, T>::value));
+
+   explicit sgtree( const value_compare &cmp = value_compare()
+                  , const value_traits &v_traits = value_traits())
+      :  Base(cmp, v_traits)
+   {}
+
+   template<class Iterator>
+   sgtree( bool unique, Iterator b, Iterator e
+         , const value_compare &cmp = value_compare()
+         , const value_traits &v_traits = value_traits())
+      :  Base(unique, b, e, cmp, v_traits)
+   {}
+
+   sgtree(BOOST_RV_REF(sgtree) x)
+      :  Base(::boost::move(static_cast<Base&>(x)))
+   {}
+
+   sgtree& operator=(BOOST_RV_REF(sgtree) x)
+   {  return static_cast<sgtree &>(this->Base::operator=(::boost::move(static_cast<Base&>(x))));  }
+
+   static sgtree &container_from_end_iterator(iterator end_iterator)
+   {  return static_cast<sgtree &>(Base::container_from_end_iterator(end_iterator));   }
+
+   static const sgtree &container_from_end_iterator(const_iterator end_iterator)
+   {  return static_cast<const sgtree &>(Base::container_from_end_iterator(end_iterator));   }
+
+   static sgtree &container_from_iterator(iterator it)
+   {  return static_cast<sgtree &>(Base::container_from_iterator(it));   }
+
+   static const sgtree &container_from_iterator(const_iterator it)
+   {  return static_cast<const sgtree &>(Base::container_from_iterator(it));   }
+};
+
+#endif
+
+} //namespace intrusive
+} //namespace boost
+
+#include <boost/intrusive/detail/config_end.hpp>
+
+#endif //BOOST_INTRUSIVE_SGTREE_HPP