63 lines
1.6 KiB
C++
63 lines
1.6 KiB
C++
/*
|
|
* Copyright Andrey Semashev 2007 - 2015.
|
|
* 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 value_extraction_fwd.hpp
|
|
* \author Andrey Semashev
|
|
* \date 01.03.2008
|
|
*
|
|
* The header contains forward declaration of tools for extracting attribute values
|
|
* from the view.
|
|
*/
|
|
|
|
#ifndef BOOST_LOG_ATTRIBUTES_VALUE_EXTRACTION_FWD_HPP_INCLUDED_
|
|
#define BOOST_LOG_ATTRIBUTES_VALUE_EXTRACTION_FWD_HPP_INCLUDED_
|
|
|
|
#include <boost/log/detail/config.hpp>
|
|
#include <boost/log/attributes/fallback_policy_fwd.hpp>
|
|
|
|
#ifdef BOOST_HAS_PRAGMA_ONCE
|
|
#pragma once
|
|
#endif
|
|
|
|
namespace boost {
|
|
|
|
BOOST_LOG_OPEN_NAMESPACE
|
|
|
|
namespace result_of {
|
|
|
|
/*!
|
|
* \brief A metafunction that allows to acquire the result of the value extraction
|
|
*/
|
|
template< typename T, typename DefaultT = T, typename TagT = void >
|
|
struct extract_or_default;
|
|
|
|
/*!
|
|
* \brief A metafunction that allows to acquire the result of the value extraction
|
|
*/
|
|
template< typename T, typename TagT = void >
|
|
struct extract_or_throw;
|
|
|
|
/*!
|
|
* \brief A metafunction that allows to acquire the result of the value extraction
|
|
*/
|
|
template< typename T, typename TagT = void >
|
|
struct extract;
|
|
|
|
} // namespace result_of
|
|
|
|
/*!
|
|
* \brief Generic attribute value extractor
|
|
*/
|
|
template< typename T, typename FallbackPolicyT = fallback_to_none, typename TagT = void >
|
|
class value_extractor;
|
|
|
|
BOOST_LOG_CLOSE_NAMESPACE // namespace log
|
|
|
|
} // namespace boost
|
|
|
|
#endif // BOOST_LOG_ATTRIBUTES_VALUE_EXTRACTION_FWD_HPP_INCLUDED_
|