ext-boost/boost/move/iterator.hpp
2014-12-28 01:22:08 -02:00

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//////////////////////////////////////////////////////////////////////////////
//
// (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
#include <boost/move/detail/config_begin.hpp>
#include <boost/move/utility_core.hpp>
#include <iterator> //std::iterator
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 std::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 std::iterator_traits<iterator_type>::difference_type difference_type;
typedef typename std::iterator_traits<iterator_type>::iterator_category iterator_category;
move_iterator()
{}
explicit move_iterator(It i)
: m_it(i)
{}
template <class U>
move_iterator(const move_iterator<U>& u)
: m_it(u.base())
{}
iterator_type base() const
{ return m_it; }
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
}
pointer operator->() const
{ return m_it; }
move_iterator& operator++()
{ ++m_it; return *this; }
move_iterator<iterator_type> operator++(int)
{ move_iterator<iterator_type> tmp(*this); ++(*this); return tmp; }
move_iterator& operator--()
{ --m_it; return *this; }
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); }
move_iterator& operator+=(difference_type n)
{ m_it += n; return *this; }
move_iterator<iterator_type> operator- (difference_type n) const
{ return move_iterator<iterator_type>(m_it - n); }
move_iterator& operator-=(difference_type n)
{ m_it -= n; return *this; }
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
}
friend bool operator==(const move_iterator& x, const move_iterator& y)
{ return x.base() == y.base(); }
friend bool operator!=(const move_iterator& x, const move_iterator& y)
{ return x.base() != y.base(); }
friend bool operator< (const move_iterator& x, const move_iterator& y)
{ return x.base() < y.base(); }
friend bool operator<=(const move_iterator& x, const move_iterator& y)
{ return x.base() <= y.base(); }
friend bool operator> (const move_iterator& x, const move_iterator& y)
{ return x.base() > y.base(); }
friend bool operator>=(const move_iterator& x, const move_iterator& y)
{ return x.base() >= y.base(); }
friend difference_type operator-(const move_iterator& x, const move_iterator& y)
{ return x.base() - y.base(); }
friend move_iterator operator+(difference_type n, const move_iterator& x)
{ return move_iterator(x.base() + 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<I> >
{
static const bool value = true;
};
} //namespace move_detail {
//////////////////////////////////////////////////////////////////////////////
//
// move_iterator
//
//////////////////////////////////////////////////////////////////////////////
//!
//! <b>Returns</b>: 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; }
};
//!
//! <b>Returns</b>: 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;
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 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; }
};
//!
//! <b>Returns</b>: 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_;
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 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; }
};
//!
//! <b>Returns</b>: 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