| ////////////////////////////////////////////////////////////////////////////// |
| // |
| // (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_MOVE_TRAITS_HPP |
| #define BOOST_MOVE_MOVE_TRAITS_HPP |
| |
| #include <boost/move/detail/config_begin.hpp> |
| #include <boost/type_traits/has_trivial_destructor.hpp> |
| #include <boost/type_traits/is_nothrow_move_constructible.hpp> |
| #include <boost/type_traits/is_nothrow_move_assignable.hpp> |
| #include <boost/type_traits/is_copy_constructible.hpp> |
| #include <boost/move/detail/meta_utils.hpp> |
| |
| #ifndef BOOST_NO_CXX11_RVALUE_REFERENCES |
| #include <boost/move/core.hpp> |
| #endif |
| |
| namespace boost { |
| |
| //! If this trait yields to true |
| //! (<i>has_trivial_destructor_after_move <T>::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::has_trivial_destructor<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::is_nothrow_move_constructible<T>::value && |
| boost::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 = boost::is_nothrow_move_constructible<T>::value || |
| has_nothrow_move<T>::value || |
| !boost::is_copy_constructible<T>::value; |
| }; |
| |
| } //move_detail { |
| } //namespace boost { |
| |
| #include <boost/move/detail/config_end.hpp> |
| |
| #endif //#ifndef BOOST_MOVE_MOVE_TRAITS_HPP |