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//////////////////////////////////////////////////////////////////////////////

//

// (C) Copyright Ion Gaztanaga 2009-2012.

// 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_TRAITS_HPP

#define BOOST_MOVE_TRAITS_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>


#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES

#include <boost/move/core.hpp>

#endif

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

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


namespace boost {

//! If this trait yields to true

//! (<i>has_trivial_destructor_after_move &lt;T&gt;::value == true</i>)

//! means that if T is used as argument of a move construction/assignment,

//! there is no need to call T's destructor.

//! This optimization tipically is used to improve containers' performance.

//!

//! By default this trait is true if the type has trivial destructor,

//! every class should specialize this trait if it wants to improve performance

//! when inserted in containers.

template <class T>
struct has_trivial_destructor_after_move
   : ::boost::move_detail::is_trivially_destructible<T>
{};

//! By default this traits returns

//! <pre>boost::is_nothrow_move_constructible<T>::value && boost::is_nothrow_move_assignable<T>::value </pre>.

//! Classes with non-throwing move constructor

//! and assignment can specialize this trait to obtain some performance improvements.

template <class T>
struct has_nothrow_move
{
   static const bool value = boost::move_detail::is_nothrow_move_constructible<T>::value &&
                             boost::move_detail::is_nothrow_move_assignable<T>::value;
};

namespace move_detail {

template <class T>
struct is_nothrow_move_constructible_or_uncopyable
{
   //The standard requires is_nothrow_move_constructible for move_if_noexcept

   //but a user (usually in C++03) might specialize has_nothrow_move which includes it

   static const bool value = is_nothrow_move_constructible<T>::value ||
                             has_nothrow_move<T>::value ||
                            !is_copy_constructible<T>::value;
};

}  //move_detail {

}  //namespace boost {


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


#endif //#ifndef BOOST_MOVE_TRAITS_HPP