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- /*
- * Copyright Andrey Semashev 2018.
- * 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)
- */
- /*!
- * \file allocator_traits.hpp
- * \author Andrey Semashev
- * \date 03.01.2018
- *
- * \brief This header is the Boost.Log library implementation, see the library documentation
- * at http://www.boost.org/doc/libs/release/libs/log/doc/html/index.html.
- */
- #ifndef BOOST_LOG_ALLOCATOR_TRAITS_HPP_INCLUDED_
- #define BOOST_LOG_ALLOCATOR_TRAITS_HPP_INCLUDED_
- #include <memory>
- #include <boost/log/detail/config.hpp>
- #if defined(BOOST_NO_CXX11_ALLOCATOR)
- #include <boost/container/allocator_traits.hpp>
- #endif
- #include <boost/log/detail/header.hpp>
- #ifdef BOOST_HAS_PRAGMA_ONCE
- #pragma once
- #endif
- namespace boost {
- BOOST_LOG_OPEN_NAMESPACE
- namespace aux {
- // A portable name for allocator traits
- #if !defined(BOOST_NO_CXX11_ALLOCATOR)
- using std::allocator_traits;
- #else
- using boost::container::allocator_traits;
- #endif
- /*!
- * \brief A standalone trait to rebind an allocator to another type.
- *
- * The important difference from <tt>std::allocator_traits<Alloc>::rebind_alloc<U></tt> is that this
- * trait does not require template aliases and thus is compatible with C++03. There is
- * <tt>boost::container::allocator_traits<Alloc>::portable_rebind_alloc<U></tt>, but it is not present in <tt>std::allocator_traits</tt>.
- * It will also attempt to instantiate the allocator type to test if it provides the nested <tt>rebind</tt> template. We don't want
- * that to happen because it prohibits using <tt>std::allocator<void></tt> in C++17 and later, which deprecated
- * this allocator specialization. This standalone trait does not use the nested <tt>rebind</tt> template in this case.
- */
- template< typename Allocator, typename U >
- struct rebind_alloc
- {
- #if !defined(BOOST_NO_CXX11_ALLOCATOR)
- typedef typename std::allocator_traits< Allocator >::BOOST_NESTED_TEMPLATE rebind_alloc< U > type;
- #else
- typedef typename boost::container::allocator_traits< Allocator >::BOOST_NESTED_TEMPLATE portable_rebind_alloc< U >::type type;
- #endif
- };
- template< typename U >
- struct rebind_alloc< std::allocator< void >, U >
- {
- typedef std::allocator< U > type;
- };
- } // namespace aux
- BOOST_LOG_CLOSE_NAMESPACE // namespace log
- } // namespace boost
- #include <boost/log/detail/footer.hpp>
- #endif // BOOST_LOG_ALLOCATOR_TRAITS_HPP_INCLUDED_
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