fsfw/contrib/fsfw_contrib/etl-20.39.4/include/etl/flat_multimap.h

///\file

/******************************************************************************
The MIT License(MIT)

Embedded Template Library.
https://github.com/ETLCPP/etl
https://www.etlcpp.com

Copyright(c) 2015 John Wellbelove

Permission is hereby granted, free of charge, to any person obtaining a copy
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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******************************************************************************/

#ifndef ETL_FLAT_MULTMAP_INCLUDED
#define ETL_FLAT_MULTMAP_INCLUDED

#include "platform.h"
#include "reference_flat_multimap.h"
#include "pool.h"
#include "utility.h"
#include "placement_new.h"
#include "nth_type.h"
#include "type_traits.h"
#include "initializer_list.h"

#include "private/comparator_is_transparent.h"

//*****************************************************************************
///\defgroup flat_multimap flat_multimap
/// A flat_multimap with the capacity defined at compile time.
/// Has insertion of O(N) and find of O(logN)
/// Duplicate entries and not allowed.
///\ingroup containers
//*****************************************************************************

namespace etl
{
  //***************************************************************************
  /// The base class for specifically sized flat_multimaps.
  /// Can be used as a reference type for all flat_multimaps containing a specific type.
  ///\ingroup flat_multimap
  //***************************************************************************
  template <typename TKey, typename TMapped, typename TKeyCompare = etl::less<TKey> >
  class iflat_multimap : public etl::ireference_flat_multimap<TKey, TMapped, TKeyCompare>
  {
  public:

    typedef ETL_OR_STD::pair<const TKey, TMapped> value_type;

  private:

    typedef etl::ireference_flat_multimap<TKey, TMapped, TKeyCompare> refmap_t;
    typedef typename refmap_t::lookup_t lookup_t;
    typedef etl::ipool         storage_t;

  public:

    typedef TKey              key_type;
    typedef TMapped           mapped_type;
    typedef TKeyCompare       key_compare;
    typedef value_type&       reference;
    typedef const value_type& const_reference;
#if ETL_USING_CPP11
    typedef value_type&&      rvalue_reference;
#endif
    typedef value_type*       pointer;
    typedef const value_type* const_pointer;
    typedef size_t            size_type;

    typedef const key_type&   const_key_reference;
#if ETL_USING_CPP11
    typedef key_type&&        rvalue_key_reference;
#endif

    typedef typename refmap_t::iterator       iterator;
    typedef typename refmap_t::const_iterator const_iterator;

    typedef ETL_OR_STD::reverse_iterator<iterator>       reverse_iterator;
    typedef ETL_OR_STD::reverse_iterator<const_iterator> const_reverse_iterator;
    typedef typename etl::iterator_traits<iterator>::difference_type difference_type;

  private:

    //*********************************************************************
    /// How to compare elements and keys.
    //*********************************************************************
    class compare
    {
    public:

      bool operator ()(const value_type& element, key_type key) const
      {
        return comp(element.first, key);
      }

      bool operator ()(key_type key, const value_type& element) const
      {
        return comp(key, element.first);
      }

      key_compare comp;
    };

  public:

    //*********************************************************************
    /// Returns an iterator to the beginning of the flat_multimap.
    ///\return An iterator to the beginning of the flat_multimap.
    //*********************************************************************
    iterator begin()
    {
      return refmap_t::begin();
    }

    //*********************************************************************
    /// Returns a const_iterator to the beginning of the flat_multimap.
    ///\return A const iterator to the beginning of the flat_multimap.
    //*********************************************************************
    const_iterator begin() const
    {
      return refmap_t::begin();
    }

    //*********************************************************************
    /// Returns an iterator to the end of the flat_multimap.
    ///\return An iterator to the end of the flat_multimap.
    //*********************************************************************
    iterator end()
    {
      return refmap_t::end();
    }

    //*********************************************************************
    /// Returns a const_iterator to the end of the flat_multimap.
    ///\return A const iterator to the end of the flat_multimap.
    //*********************************************************************
    const_iterator end() const
    {
      return refmap_t::end();
    }

    //*********************************************************************
    /// Returns a const_iterator to the beginning of the flat_multimap.
    ///\return A const iterator to the beginning of the flat_multimap.
    //*********************************************************************
    const_iterator cbegin() const
    {
      return refmap_t::cbegin();
    }

    //*********************************************************************
    /// Returns a const_iterator to the end of the flat_multimap.
    ///\return A const iterator to the end of the flat_multimap.
    //*********************************************************************
    const_iterator cend() const
    {
      return refmap_t::cend();
    }

    //*********************************************************************
    /// Returns an reverse iterator to the reverse beginning of the flat_multimap.
    ///\return Iterator to the reverse beginning of the flat_multimap.
    //*********************************************************************
    reverse_iterator rbegin()
    {
      return refmap_t::rbegin();
    }

    //*********************************************************************
    /// Returns a const reverse iterator to the reverse beginning of the flat_multimap.
    ///\return Const iterator to the reverse beginning of the flat_multimap.
    //*********************************************************************
    const_reverse_iterator rbegin() const
    {
      return refmap_t::rbegin();
    }

    //*********************************************************************
    /// Returns a reverse iterator to the end + 1 of the flat_multimap.
    ///\return Reverse iterator to the end + 1 of the flat_multimap.
    //*********************************************************************
    reverse_iterator rend()
    {
      return refmap_t::rend();
    }

    //*********************************************************************
    /// Returns a const reverse iterator to the end + 1 of the flat_multimap.
    ///\return Const reverse iterator to the end + 1 of the flat_multimap.
    //*********************************************************************
    const_reverse_iterator rend() const
    {
      return refmap_t::rend();
    }

    //*********************************************************************
    /// Returns a const reverse iterator to the reverse beginning of the flat_multimap.
    ///\return Const reverse iterator to the reverse beginning of the flat_multimap.
    //*********************************************************************
    const_reverse_iterator crbegin() const
    {
      return refmap_t::crbegin();
    }

    //*********************************************************************
    /// Returns a const reverse iterator to the end + 1 of the flat_multimap.
    ///\return Const reverse iterator to the end + 1 of the flat_multimap.
    //*********************************************************************
    const_reverse_iterator crend() const
    {
      return refmap_t::crend();
    }

    //*********************************************************************
    /// Assigns values to the flat_multimap.
    /// If asserts or exceptions are enabled, emits flat_multimap_full if the flat_multimap does not have enough free space.
    /// If asserts or exceptions are enabled, emits flat_multimap_iterator if the iterators are reversed.
    ///\param first The iterator to the first element.
    ///\param last  The iterator to the last element + 1.
    //*********************************************************************
    template <typename TIterator>
    void assign(TIterator first, TIterator last)
    {
#if ETL_IS_DEBUG_BUILD
      difference_type d = etl::distance(first, last);
      ETL_ASSERT(d <= difference_type(capacity()), ETL_ERROR(flat_multimap_full));
#endif

      clear();

      while (first != last)
      {
        insert(*first);
        ++first;
      }
    }

    //*********************************************************************
    /// Inserts a value to the flat_multimap.
    /// If asserts or exceptions are enabled, emits flat_multimap_full if the flat_multimap is already full.
    ///\param value    The value to insert.
    //*********************************************************************
    ETL_OR_STD::pair<iterator, bool> insert(const value_type& value)
    {
      ETL_ASSERT(!refmap_t::full(), ETL_ERROR(flat_multimap_full));

      ETL_OR_STD::pair<iterator, bool> result(end(), false);

      iterator i_element = upper_bound(value.first);

      value_type* pvalue = storage.allocate<value_type>();
      ::new (pvalue) value_type(value);
      ETL_INCREMENT_DEBUG_COUNT;
      result = refmap_t::insert_at(i_element, *pvalue);

      return result;
    }

#if ETL_USING_CPP11
    //*********************************************************************
    /// Inserts a value to the flat_multimap.
    /// If asserts or exceptions are enabled, emits flat_multimap_full if the flat_multimap is already full.
    ///\param value    The value to insert.
    //*********************************************************************
    ETL_OR_STD::pair<iterator, bool> insert(rvalue_reference value)
    {
      ETL_ASSERT(!refmap_t::full(), ETL_ERROR(flat_multimap_full));

      ETL_OR_STD::pair<iterator, bool> result(end(), false);

      iterator i_element = upper_bound(value.first);

      value_type* pvalue = storage.allocate<value_type>();
      ::new (pvalue) value_type(etl::move(value));
      ETL_INCREMENT_DEBUG_COUNT;
      result = refmap_t::insert_at(i_element, *pvalue);

      return result;
    }
#endif

    //*********************************************************************
    /// Inserts a value to the flat_multimap.
    /// If asserts or exceptions are enabled, emits flat_multimap_full if the flat_multimap_full is already full.
    ///\param position The position to insert at.
    ///\param value    The value to insert.
    //*********************************************************************
    iterator insert(const_iterator /*position*/, const value_type& value)
    {
      return insert(value).first;
    }

#if ETL_USING_CPP11
    //*********************************************************************
    /// Moves a value to the flat_multimap.
    /// If asserts or exceptions are enabled, emits flat_multimap_full if the flat_multimap_full is already full.
    ///\param position The position to insert at.
    ///\param value    The value to insert.
    //*********************************************************************
    iterator insert(const_iterator /*position*/, rvalue_reference value)
    {
      return insert(etl::move(value)).first;
    }
#endif

    //*********************************************************************
    /// Inserts a range of values to the flat_multimap.
    /// If asserts or exceptions are enabled, emits flat_multimap_full if the flat_multimap does not have enough free space.
    ///\param position The position to insert at.
    ///\param first    The first element to add.
    ///\param last     The last + 1 element to add.
    //*********************************************************************
    template <class TIterator>
    void insert(TIterator first, TIterator last)
    {
      while (first != last)
      {
        insert(*first);
        ++first;
      }
    }

    //*************************************************************************
    /// Emplaces a value to the map.
    //*************************************************************************
    ETL_OR_STD::pair<iterator, bool> emplace(const value_type& value)
    {
      return insert(value);
    }

    //*************************************************************************
    /// Emplaces a value to the map.
    //*************************************************************************
    ETL_OR_STD::pair<iterator, bool> emplace(const key_type& key, const mapped_type& mapped)
    {
      ETL_ASSERT(!full(), ETL_ERROR(flat_multimap_full));

      // Create it.
      value_type* pvalue = storage.allocate<value_type>();
      ::new ((void*)etl::addressof(pvalue->first)) key_type(key);
      ::new ((void*)etl::addressof(pvalue->second)) mapped_type(mapped);
      iterator i_element = upper_bound(key);
      ETL_INCREMENT_DEBUG_COUNT;

      return refmap_t::insert_at(i_element, *pvalue);
    }

#if ETL_USING_CPP11 && ETL_NOT_USING_STLPORT
    //*************************************************************************
    /// Emplaces a value to the map.
    //*************************************************************************
    template <typename ... Args>
    ETL_OR_STD::pair<iterator, bool> emplace(const key_type& key, Args && ... args)
    {
      ETL_ASSERT(!full(), ETL_ERROR(flat_multimap_full));

      // Create it.
      value_type* pvalue = storage.allocate<value_type>();
      ::new ((void*)etl::addressof(pvalue->first)) key_type(key);
      ::new ((void*)etl::addressof(pvalue->second)) mapped_type(etl::forward<Args>(args)...);
      iterator i_element = upper_bound(key);
      ETL_INCREMENT_DEBUG_COUNT;

      return refmap_t::insert_at(i_element, *pvalue);
    }

#else
    //*************************************************************************
    /// Emplaces a value to the map.
    //*************************************************************************
    template <typename T1>
    ETL_OR_STD::pair<iterator, bool> emplace(const key_type& key, const T1& value1)
    {
      ETL_ASSERT(!full(), ETL_ERROR(flat_multimap_full));

      // Create it.
      value_type* pvalue = storage.allocate<value_type>();
      ::new ((void*)etl::addressof(pvalue->first)) key_type(key);
      ::new ((void*)etl::addressof(pvalue->second)) mapped_type(value1);
      iterator i_element = upper_bound(key);
      ETL_INCREMENT_DEBUG_COUNT;

      return refmap_t::insert_at(i_element, *pvalue);
    }

    //*************************************************************************
    /// Emplaces a value to the map.
    //*************************************************************************
    template <typename T1, typename T2>
    ETL_OR_STD::pair<iterator, bool> emplace(const key_type& key, const T1& value1, const T2& value2)
    {
      ETL_ASSERT(!full(), ETL_ERROR(flat_multimap_full));

      // Create it.
      value_type* pvalue = storage.allocate<value_type>();
      ::new ((void*)etl::addressof(pvalue->first)) key_type(key);
      ::new ((void*)etl::addressof(pvalue->second)) mapped_type(value1, value2);
      iterator i_element = upper_bound(key);
      ETL_INCREMENT_DEBUG_COUNT;

      return refmap_t::insert_at(i_element, *pvalue);
    }

    //*************************************************************************
    /// Emplaces a value to the map.
    //*************************************************************************
    template <typename T1, typename T2, typename T3>
    ETL_OR_STD::pair<iterator, bool> emplace(const key_type& key, const T1& value1, const T2& value2, const T3& value3)
    {
      ETL_ASSERT(!full(), ETL_ERROR(flat_multimap_full));

      // Create it.
      value_type* pvalue = storage.allocate<value_type>();
      ::new ((void*)etl::addressof(pvalue->first)) key_type(key);
      ::new ((void*)etl::addressof(pvalue->second)) mapped_type(value1, value2, value3);
      iterator i_element = upper_bound(key);
      ETL_INCREMENT_DEBUG_COUNT;

      return refmap_t::insert_at(i_element, *pvalue);
    }

    //*************************************************************************
    /// Emplaces a value to the map.
    //*************************************************************************
    template <typename T1, typename T2, typename T3, typename T4>
    ETL_OR_STD::pair<iterator, bool> emplace(const key_type& key, const T1& value1, const T2& value2, const T3& value3, const T4& value4)
    {
      ETL_ASSERT(!full(), ETL_ERROR(flat_multimap_full));

      // Create it.
      value_type* pvalue = storage.allocate<value_type>();
      ::new ((void*)etl::addressof(pvalue->first)) key_type(key);
      ::new ((void*)etl::addressof(pvalue->second)) mapped_type(value1, value2, value3, value4);
      iterator i_element = upper_bound(key);
      ETL_INCREMENT_DEBUG_COUNT;

      return refmap_t::insert_at(i_element, *pvalue);
    }

#endif

    //*********************************************************************
    /// Erases an element.
    ///\param key The key to erase.
    ///\return The number of elements erased. 0 or 1.
    //*********************************************************************
    size_t erase(const_key_reference key)
    {
      ETL_OR_STD::pair<iterator, iterator> range = equal_range(key);

      if (range.first == end())
      {
        return 0;
      }
      else
      {
        size_t d = etl::distance(range.first, range.second);
        erase(range.first, range.second);
        return d;
      }
    }

#if ETL_USING_CPP11
    //*********************************************************************
    template <typename K, typename KC = TKeyCompare, etl::enable_if_t<comparator_is_transparent<KC>::value, int> = 0>
    size_t erase(K&& key)
    {
      ETL_OR_STD::pair<iterator, iterator> range = equal_range(etl::forward<K>(key));

      if (range.first == end())
      {
        return 0;
      }
      else
      {
        size_t d = etl::distance(range.first, range.second);
        erase(range.first, range.second);
        return d;
      }
    }
#endif

    //*********************************************************************
    /// Erases an element.
    ///\param i_element Iterator to the element.
    //*********************************************************************
    iterator erase(iterator i_element)
    {
      i_element->~value_type();
      storage.release(etl::addressof(*i_element));
      ETL_DECREMENT_DEBUG_COUNT;
      return refmap_t::erase(i_element);
    }

    //*********************************************************************
    /// Erases an element.
    ///\param i_element Iterator to the element.
    //*********************************************************************
    iterator erase(const_iterator i_element)
    {
      i_element->~value_type();
      storage.release(etl::addressof(*i_element));
      ETL_DECREMENT_DEBUG_COUNT;
      return refmap_t::erase(i_element);
    }

    //*********************************************************************
    /// Erases a range of elements.
    /// The range includes all the elements between first and last, including the
    /// element pointed by first, but not the one pointed by last.
    ///\param first Iterator to the first element.
    ///\param last  Iterator to the last element.
    //*********************************************************************
    iterator erase(const_iterator first, const_iterator last)
    {
      const_iterator itr = first;

      while (itr != last)
      {
        itr->~value_type();
        storage.release(etl::addressof(*itr));
        ++itr;
        ETL_DECREMENT_DEBUG_COUNT;
      }

      return refmap_t::erase(first, last);
    }

    //*************************************************************************
    /// Clears the flat_multimap.
    //*************************************************************************
    void clear()
    {
      if ETL_IF_CONSTEXPR(etl::is_trivially_destructible<value_type>::value)
      {
        storage.release_all();
      }
      else
      {
        iterator itr = begin();

        while (itr != end())
        {
          itr->~value_type();
          storage.release(etl::addressof(*itr));
          ++itr;
        }
      }

      ETL_RESET_DEBUG_COUNT;
      refmap_t::clear();
    }

    //*********************************************************************
    /// Finds an element.
    ///\param key The key to search for.
    ///\return An iterator pointing to the element or end() if not found.
    //*********************************************************************
    iterator find(const_key_reference key)
    {
      return refmap_t::find(key);
    }

#if ETL_USING_CPP11
    //*********************************************************************
    template <typename K, typename KC = TKeyCompare, etl::enable_if_t<comparator_is_transparent<KC>::value, int> = 0>
    iterator find(const K& key)
    {
      return refmap_t::find(key);
    }
#endif

    //*********************************************************************
    /// Finds an element.
    ///\param key The key to search for.
    ///\return An iterator pointing to the element or end() if not found.
    //*********************************************************************
    const_iterator find(const_key_reference key) const
    {
      return refmap_t::find(key);
    }

#if ETL_USING_CPP11
    //*********************************************************************
    template <typename K, typename KC = TKeyCompare, etl::enable_if_t<comparator_is_transparent<KC>::value, int> = 0>
    const_iterator find(const K& key) const
    {
      return refmap_t::find(key);
    }
#endif

    //*********************************************************************
    /// Counts an element.
    ///\param key The key to search for.
    ///\return 1 if the key exists, otherwise 0.
    //*********************************************************************
    size_t count(const_key_reference key) const
    {
      return refmap_t::count(key);
    }

#if ETL_USING_CPP11
    //*********************************************************************
    template <typename K, typename KC = TKeyCompare, etl::enable_if_t<comparator_is_transparent<KC>::value, int> = 0>
    size_t count(const K& key) const
    {
      return refmap_t::count(key);
    }
#endif

    //*********************************************************************
    /// Finds the lower bound of a key
    ///\param key The key to search for.
    ///\return An iterator.
    //*********************************************************************
    iterator lower_bound(const_key_reference key)
    {
      return refmap_t::lower_bound(key);
    }

#if ETL_USING_CPP11
    //*********************************************************************
    template <typename K, typename KC = TKeyCompare, etl::enable_if_t<comparator_is_transparent<KC>::value, int> = 0>
    iterator lower_bound(const K& key)
    {
      return refmap_t::lower_bound(key);
    }
#endif

    //*********************************************************************
    /// Finds the lower bound of a key
    ///\param key The key to search for.
    ///\return An iterator.
    //*********************************************************************
    const_iterator lower_bound(const_key_reference key) const
    {
      return refmap_t::lower_bound(key);
    }

#if ETL_USING_CPP11
    //*********************************************************************
    template <typename K, typename KC = TKeyCompare, etl::enable_if_t<comparator_is_transparent<KC>::value, int> = 0>
    const_iterator lower_bound(const K& key) const
    {
      return refmap_t::lower_bound(key);
    }
#endif

    //*********************************************************************
    /// Finds the upper bound of a key
    ///\param key The key to search for.
    ///\return An iterator.
    //*********************************************************************
    iterator upper_bound(const_key_reference key)
    {
      return refmap_t::upper_bound(key);
    }

#if ETL_USING_CPP11
    //*********************************************************************
    template <typename K, typename KC = TKeyCompare, etl::enable_if_t<comparator_is_transparent<KC>::value, int> = 0>
    iterator upper_bound(const K& key)
    {
      return refmap_t::upper_bound(key);
    }
#endif

    //*********************************************************************
    /// Finds the upper bound of a key
    ///\param key The key to search for.
    ///\return An iterator.
    //*********************************************************************
    const_iterator upper_bound(const_key_reference key) const
    {
      return refmap_t::upper_bound(key);
    }

#if ETL_USING_CPP11
    //*********************************************************************
    template <typename K, typename KC = TKeyCompare, etl::enable_if_t<comparator_is_transparent<KC>::value, int> = 0>
    const_iterator upper_bound(const K& key) const
    {
      return refmap_t::upper_bound(key);
    }
#endif

    //*********************************************************************
    /// Finds the range of equal elements of a key
    ///\param key The key to search for.
    ///\return An iterator pair.
    //*********************************************************************
    ETL_OR_STD::pair<iterator, iterator> equal_range(const_key_reference key)
    {
      return refmap_t::equal_range(key);
    }

#if ETL_USING_CPP11
    //*********************************************************************
    template <typename K, typename KC = TKeyCompare, etl::enable_if_t<comparator_is_transparent<KC>::value, int> = 0>
    ETL_OR_STD::pair<iterator, iterator> equal_range(const K& key)
    {
      return refmap_t::equal_range(key);
    }
#endif

    //*********************************************************************
    /// Finds the range of equal elements of a key
    ///\param key The key to search for.
    ///\return An iterator pair.
    //*********************************************************************
    ETL_OR_STD::pair<const_iterator, const_iterator> equal_range(const_key_reference key) const
    {
      return refmap_t::equal_range(key);
    }

#if ETL_USING_CPP11
    //*********************************************************************
    template <typename K, typename KC = TKeyCompare, etl::enable_if_t<comparator_is_transparent<KC>::value, int> = 0>
    ETL_OR_STD::pair<const_iterator, const_iterator> equal_range(const K& key) const
    {
      return refmap_t::equal_range(key);
    }
#endif

    //*************************************************************************
    /// Check if the map contains the key.
    //*************************************************************************
    bool contains(const_key_reference key) const
    {
      return find(key) != end();
    }

#if ETL_USING_CPP11
    //*************************************************************************
    template <typename K, typename KC = TKeyCompare, etl::enable_if_t<comparator_is_transparent<KC>::value, int> = 0>
    bool contains(const K& k) const
    {
      return find(k) != end();
    }
#endif

    //*************************************************************************
    /// Assignment operator.
    //*************************************************************************
    iflat_multimap& operator = (const iflat_multimap& rhs)
    {
      if (&rhs != this)
      {
        assign(rhs.cbegin(), rhs.cend());
      }

      return *this;
    }

#if ETL_USING_CPP11
    //*************************************************************************
    /// Move assignment operator.
    //*************************************************************************
    iflat_multimap& operator = (iflat_multimap&& rhs)
    {
      move_container(etl::move(rhs));

      return *this;
    }
#endif

    //*************************************************************************
    /// Gets the current size of the flat_multiset.
    ///\return The current size of the flat_multiset.
    //*************************************************************************
    size_type size() const
    {
      return refmap_t::size();
    }

    //*************************************************************************
    /// Checks the 'empty' state of the flat_multiset.
    ///\return <b>true</b> if empty.
    //*************************************************************************
    bool empty() const
    {
      return refmap_t::empty();
    }

    //*************************************************************************
    /// Checks the 'full' state of the flat_multiset.
    ///\return <b>true</b> if full.
    //*************************************************************************
    bool full() const
    {
      return refmap_t::full();
    }

    //*************************************************************************
    /// Returns the capacity of the flat_multiset.
    ///\return The capacity of the flat_multiset.
    //*************************************************************************
    size_type capacity() const
    {
      return refmap_t::capacity();
    }

    //*************************************************************************
    /// Returns the maximum possible size of the flat_multiset.
    ///\return The maximum size of the flat_multiset.
    //*************************************************************************
    size_type max_size() const
    {
      return refmap_t::max_size();
    }

    //*************************************************************************
    /// Returns the remaining capacity.
    ///\return The remaining capacity.
    //*************************************************************************
    size_t available() const
    {
      return refmap_t::available();
    }

  protected:

    //*********************************************************************
    /// Constructor.
    //*********************************************************************
    iflat_multimap(lookup_t& lookup_, storage_t& storage_)
      : refmap_t(lookup_),
        storage(storage_)
    {
    }

#if ETL_USING_CPP11
    //*************************************************************************
    /// Move a flat_multimap.
    /// Assumes the flat_multimap is initialised and empty.
    //*************************************************************************
    void move_container(iflat_multimap&& rhs)
    {
      if (&rhs != this)
      {
        this->clear();

        etl::iflat_multimap<TKey, TMapped, TKeyCompare>::iterator first = rhs.begin();
        etl::iflat_multimap<TKey, TMapped, TKeyCompare>::iterator last = rhs.end();

        // Move all of the elements.
        while (first != last)
        {
          typename etl::iflat_multimap<TKey, TMapped, TKeyCompare>::iterator temp = first;
          ++temp;

          this->insert(etl::move(*first));
          first = temp;
        }
      }
    }
#endif

  private:

    // Disable copy construction.
    iflat_multimap(const iflat_multimap&);

    storage_t& storage;

    /// Internal debugging.
    ETL_DECLARE_DEBUG_COUNT;

    //*************************************************************************
    /// Destructor.
    //*************************************************************************
#if defined(ETL_POLYMORPHIC_FLAT_MULTIMAP) || defined(ETL_POLYMORPHIC_CONTAINERS)
  public:
    virtual ~iflat_multimap()
    {
    }
#else
  protected:
    ~iflat_multimap()
    {
    }
#endif
  };

  //***************************************************************************
  /// Equal operator.
  ///\param lhs Reference to the first flat_multimap.
  ///\param rhs Reference to the second flat_multimap.
  ///\return <b>true</b> if the arrays are equal, otherwise <b>false</b>
  ///\ingroup flat_multimap
  //***************************************************************************
  template <typename TKey, typename TMapped, typename TKeyCompare>
  bool operator ==(const etl::iflat_multimap<TKey, TMapped, TKeyCompare>& lhs, const etl::iflat_multimap<TKey, TMapped, TKeyCompare>& rhs)
  {
    return (lhs.size() == rhs.size()) && etl::equal(lhs.begin(), lhs.end(), rhs.begin());
  }

  //***************************************************************************
  /// Not equal operator.
  ///\param lhs Reference to the first flat_multimap.
  ///\param rhs Reference to the second flat_multimap.
  ///\return <b>true</b> if the arrays are not equal, otherwise <b>false</b>
  ///\ingroup flat_multimap
  //***************************************************************************
  template <typename TKey, typename TMapped, typename TKeyCompare>
  bool operator !=(const etl::iflat_multimap<TKey, TMapped, TKeyCompare>& lhs, const etl::iflat_multimap<TKey, TMapped, TKeyCompare>& rhs)
  {
    return !(lhs == rhs);
  }

  //***************************************************************************
  /// A flat_multimap implementation that uses a fixed size buffer.
  ///\tparam TKey     The key type.
  ///\tparam TValue   The value type.
  ///\tparam TCompare The type to compare keys. Default = etl::less<TKey>
  ///\tparam MAX_SIZE_ The maximum number of elements that can be stored.
  ///\ingroup flat_multimap
  //***************************************************************************
  template <typename TKey, typename TValue, const size_t MAX_SIZE_, typename TCompare = etl::less<TKey> >
  class flat_multimap : public etl::iflat_multimap<TKey, TValue, TCompare>
  {
  public:

    static ETL_CONSTANT size_t MAX_SIZE = MAX_SIZE_;

    //*************************************************************************
    /// Constructor.
    //*************************************************************************
    flat_multimap()
      : etl::iflat_multimap<TKey, TValue, TCompare>(lookup, storage)
    {
    }

    //*************************************************************************
    /// Copy constructor.
    //*************************************************************************
    flat_multimap(const flat_multimap& other)
      : etl::iflat_multimap<TKey, TValue, TCompare>(lookup, storage)
    {
      this->assign(other.cbegin(), other.cend());
    }

#if ETL_USING_CPP11
    //*************************************************************************
    /// Move constructor.
    //*************************************************************************
    flat_multimap(flat_multimap&& other)
      : etl::iflat_multimap<TKey, TValue, TCompare>(lookup, storage)
    {
      if (&other != this)
      {
        this->move_container(etl::move(other));
      }
    }
#endif

    //*************************************************************************
    /// Constructor, from an iterator range.
    ///\tparam TIterator The iterator type.
    ///\param first The iterator to the first element.
    ///\param last  The iterator to the last element + 1.
    //*************************************************************************
    template <typename TIterator>
    flat_multimap(TIterator first, TIterator last)
      : etl::iflat_multimap<TKey, TValue, TCompare>(lookup, storage)
    {
      this->assign(first, last);
    }

#if ETL_HAS_INITIALIZER_LIST
    //*************************************************************************
    /// Construct from initializer_list.
    //*************************************************************************
    flat_multimap(std::initializer_list<typename etl::iflat_multimap<TKey, TValue, TCompare>::value_type> init)
      : etl::iflat_multimap<TKey, TValue, TCompare>(lookup, storage)
    {
      this->assign(init.begin(), init.end());
    }
#endif

    //*************************************************************************
    /// Destructor.
    //*************************************************************************
    ~flat_multimap()
    {
      this->clear();
    }

    //*************************************************************************
    /// Assignment operator.
    //*************************************************************************
    flat_multimap& operator = (const flat_multimap& rhs)
    {
      if (&rhs != this)
      {
        this->assign(rhs.cbegin(), rhs.cend());
      }

      return *this;
    }

#if ETL_USING_CPP11
    //*************************************************************************
    /// Move assignment operator.
    //*************************************************************************
    flat_multimap& operator = (flat_multimap&& rhs)
    {
      if (&rhs != this)
      {
        this->move_container(etl::move(rhs));
      }

      return *this;
    }
#endif

  private:

    typedef typename etl::iflat_multimap<TKey, TValue, TCompare>::value_type node_t;

    // The pool of nodes.
    etl::pool<node_t, MAX_SIZE> storage;

    // The vector that stores pointers to the nodes.
    etl::vector<node_t*, MAX_SIZE> lookup;
  };

  template <typename TKey, typename TValue, const size_t MAX_SIZE_, typename TCompare>
  ETL_CONSTANT size_t flat_multimap<TKey, TValue, MAX_SIZE_, TCompare>::MAX_SIZE;

  //*************************************************************************
  /// Template deduction guides.
  //*************************************************************************
#if ETL_USING_CPP17 && ETL_HAS_INITIALIZER_LIST
  template <typename... TPairs>
  flat_multimap(TPairs...) -> flat_multimap<typename etl::nth_type_t<0, TPairs...>::first_type,
                                            typename etl::nth_type_t<0, TPairs...>::second_type,
                                            sizeof...(TPairs)>;
#endif

  //*************************************************************************
  /// Make
  //*************************************************************************
#if ETL_USING_CPP11 && ETL_HAS_INITIALIZER_LIST
  template <typename TKey, typename TMapped, typename TKeyCompare = etl::less<TKey>, typename... TPairs>
  constexpr auto make_flat_multimap(TPairs&&... pairs) -> etl::flat_multimap<TKey, TMapped, sizeof...(TPairs), TKeyCompare>
  {
    return { etl::forward<TPairs>(pairs)... };
  }
#endif
}

#endif