관리-도구

편집 파일: iterator.hpp

//////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Ion Gaztanaga 2012-2012.
// 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/move for documentation.
//
//////////////////////////////////////////////////////////////////////////////

//! \file

#ifndef BOOST_MOVE_ITERATOR_HPP
#define BOOST_MOVE_ITERATOR_HPP

#ifndef BOOST_CONFIG_HPP
# include <boost/config.hpp>
#endif
#
#if defined(BOOST_HAS_PRAGMA_ONCE)
# pragma once
#endif

#include <boost/move/detail/config_begin.hpp>
#include <boost/move/detail/workaround.hpp> //forceinline
#include <boost/move/detail/iterator_traits.hpp>
#include <boost/move/utility_core.hpp>

namespace boost {

//////////////////////////////////////////////////////////////////////////////
//
//                            move_iterator
//
//////////////////////////////////////////////////////////////////////////////

//! Class template move_iterator is an iterator adaptor with the same behavior
//! as the underlying iterator except that its dereference operator implicitly
//! converts the value returned by the underlying iterator's dereference operator
//! to an rvalue reference. Some generic algorithms can be called with move
//! iterators to replace copying with moving.
template <class It>
class move_iterator
{
 public:
 typedef It iterator_type;
 typedef typename boost::movelib::iterator_traits<iterator_type>::value_type value_type;
 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) || defined(BOOST_MOVE_DOXYGEN_INVOKED)
 typedef value_type && reference;
 #else
 typedef typename ::boost::move_detail::if_
 < ::boost::has_move_emulation_enabled<value_type>
 , ::boost::rv<value_type>&
 , value_type & >::type reference;
 #endif
 typedef It pointer;
 typedef typename boost::movelib::iterator_traits<iterator_type>::difference_type difference_type;
 typedef typename boost::movelib::iterator_traits<iterator_type>::iterator_category iterator_category;

inline move_iterator()
      : m_it()
   {}

inline explicit move_iterator(const It &i)
      :  m_it(i)
   {}

template <class U>
 inline move_iterator(const move_iterator& u)
 : m_it(u.m_it)
 {}

inline reference operator*() const
   {
      #if defined(BOOST_NO_CXX11_RVALUE_REFERENCES) || defined(BOOST_MOVE_OLD_RVALUE_REF_BINDING_RULES)
      return *m_it;
      #else
      return ::boost::move(*m_it);
      #endif
   }

inline pointer   operator->() const
   {  return m_it;   }

inline move_iterator& operator++()
   {  ++m_it; return *this;   }

inline move_iterator<iterator_type> operator++(int)
 { move_iterator<iterator_type> tmp(*this); ++(*this); return tmp; }

inline move_iterator& operator--()
   {  --m_it; return *this;   }

inline move_iterator<iterator_type> operator--(int)
 { move_iterator<iterator_type> tmp(*this); --(*this); return tmp; }

move_iterator<iterator_type> operator+ (difference_type n) const
 { return move_iterator<iterator_type>(m_it + n); }

inline move_iterator& operator+=(difference_type n)
   {  m_it += n; return *this;   }

inline move_iterator<iterator_type> operator- (difference_type n) const
 { return move_iterator<iterator_type>(m_it - n); }

inline move_iterator& operator-=(difference_type n)
   {  m_it -= n; return *this;   }

inline reference operator[](difference_type n) const
   {
      #if defined(BOOST_NO_CXX11_RVALUE_REFERENCES) || defined(BOOST_MOVE_OLD_RVALUE_REF_BINDING_RULES)
      return m_it[n];
      #else
      return ::boost::move(m_it[n]);
      #endif
   }

inline friend bool operator==(const move_iterator& x, const move_iterator& y)
   {  return x.m_it == y.m_it;  }

inline friend bool operator!=(const move_iterator& x, const move_iterator& y)
   {  return x.m_it != y.m_it;  }

inline friend bool operator< (const move_iterator& x, const move_iterator& y)
 { return x.m_it < y.m_it; }

inline friend bool operator<=(const move_iterator& x, const move_iterator& y)
 { return x.m_it <= y.m_it; }

inline friend bool operator> (const move_iterator& x, const move_iterator& y)
   {  return x.m_it > y.m_it;  }

inline friend bool operator>=(const move_iterator& x, const move_iterator& y)
   {  return x.m_it >= y.m_it;  }

inline friend difference_type operator-(const move_iterator& x, const move_iterator& y)
   {  return x.m_it - y.m_it;   }

inline friend move_iterator operator+(difference_type n, const move_iterator& x)
   {  return move_iterator(x.m_it + n);   }

private:
   It m_it;
};

//is_move_iterator
namespace move_detail {

template <class I>
struct is_move_iterator
{
 static const bool value = false;
};

template <class I>
struct is_move_iterator< ::boost::move_iterator >
{
 static const bool value = true;
};

}  //namespace move_detail {

//!
//! Returns: move_iterator<It>(i).
template<class It>
inline move_iterator<It> make_move_iterator(const It &it)
{ return move_iterator<It>(it); }

//////////////////////////////////////////////////////////////////////////////
//
//                         back_move_insert_iterator
//
//////////////////////////////////////////////////////////////////////////////

//! A move insert iterator that move constructs elements at the
//! back of a container
template <typename C> // C models Container
class back_move_insert_iterator
{
 C* container_m;

public:
   typedef C                           container_type;
   typedef typename C::value_type      value_type;
   typedef typename C::reference       reference;
   typedef typename C::pointer         pointer;
   typedef typename C::difference_type difference_type;
   typedef std::output_iterator_tag    iterator_category;

explicit back_move_insert_iterator(C& x) : container_m(&x) { }

back_move_insert_iterator& operator=(reference x)
   { container_m->push_back(boost::move(x)); return *this; }

back_move_insert_iterator& operator=(BOOST_RV_REF(value_type) x)
   {  reference rx = x; return this->operator=(rx);  }

back_move_insert_iterator& operator*()     { return *this; }
   back_move_insert_iterator& operator++()    { return *this; }
   back_move_insert_iterator& operator++(int) { return *this; }
};

//!
//! Returns: back_move_insert_iterator<C>(x).
template <typename C> // C models Container
inline back_move_insert_iterator<C> back_move_inserter(C& x)
{
 return back_move_insert_iterator<C>(x);
}

//////////////////////////////////////////////////////////////////////////////
//
//                         front_move_insert_iterator
//
//////////////////////////////////////////////////////////////////////////////

//! A move insert iterator that move constructs elements int the
//! front of a container
template <typename C> // C models Container
class front_move_insert_iterator
{
 C* container_m;

explicit front_move_insert_iterator(C& x) : container_m(&x) { }

front_move_insert_iterator& operator=(reference x)
   { container_m->push_front(boost::move(x)); return *this; }

front_move_insert_iterator& operator=(BOOST_RV_REF(value_type) x)
   {  reference rx = x; return this->operator=(rx);  }

front_move_insert_iterator& operator*()     { return *this; }
   front_move_insert_iterator& operator++()    { return *this; }
   front_move_insert_iterator& operator++(int) { return *this; }
};

//!
//! Returns: front_move_insert_iterator<C>(x).
template <typename C> // C models Container
inline front_move_insert_iterator<C> front_move_inserter(C& x)
{
 return front_move_insert_iterator<C>(x);
}

//////////////////////////////////////////////////////////////////////////////
//
// insert_move_iterator
//
//////////////////////////////////////////////////////////////////////////////
template <typename C> // C models Container
class move_insert_iterator
{
 C* container_m;
 typename C::iterator pos_;

explicit move_insert_iterator(C& x, typename C::iterator pos)
      : container_m(&x), pos_(pos)
   {}

move_insert_iterator& operator=(reference x)
   {
      pos_ = container_m->insert(pos_, ::boost::move(x));
      ++pos_;
      return *this;
   }

move_insert_iterator& operator=(BOOST_RV_REF(value_type) x)
   {  reference rx = x; return this->operator=(rx);  }

move_insert_iterator& operator*()     { return *this; }
   move_insert_iterator& operator++()    { return *this; }
   move_insert_iterator& operator++(int) { return *this; }
};

//!
//! Returns: move_insert_iterator<C>(x, it).
template <typename C> // C models Container
inline move_insert_iterator<C> move_inserter(C& x, typename C::iterator it)
{
 return move_insert_iterator<C>(x, it);
}

}  //namespace boost {

#include <boost/move/detail/config_end.hpp>

#endif //#ifndef BOOST_MOVE_ITERATOR_HPP