iostreams/detail/forward.hpp

0001 // (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
0002 // (C) Copyright 2003-2007 Jonathan Turkanis
0003 // Distributed under the Boost Software License, Version 1.0. (See accompanying
0004 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
0005
0006 // See http://www.boost.org/libs/iostreams for documentation.
0007
0008 #ifndef BOOST_IOSTREAMS_DETAIL_FORWARD_HPP_INCLUDED
0009 #define BOOST_IOSTREAMS_DETAIL_FORWARD_HPP_INCLUDED
0010
0011 #if defined(_MSC_VER)
0012 # pragma once
0013 #endif
0014
0015 #include <boost/config.hpp> // BOOST_MSVC, BOOST_NO_SFINAE
0016 #include <boost/detail/workaround.hpp>
0017 #include <boost/iostreams/detail/config/limits.hpp>
0018 #include <boost/iostreams/detail/push_params.hpp>
0019 #include <boost/preprocessor/arithmetic/dec.hpp>
0020 #include <boost/preprocessor/arithmetic/inc.hpp>
0021 #include <boost/preprocessor/punctuation/comma_if.hpp>
0022 #include <boost/preprocessor/repetition/enum_binary_params.hpp>
0023 #include <boost/preprocessor/repetition/enum_params.hpp>
0024 #include <boost/preprocessor/repetition/repeat_from_to.hpp>
0025 #include <boost/preprocessor/tuple/elem.hpp>
0026 #include <boost/type_traits/is_same.hpp>
0027
0028 //------Macros for defining forwarding constructors and open overloads--------//
0029
0030 //
0031 // Macro: BOOST_IOSTREAMS_FORWARD(class, impl, device, params, args)
0032 // Description: Defines constructors and overloads of 'open' which construct
0033 //      a device using the specified argument list and pass it to the specified
0034 //      helper function
0035 //   class - The class name
0036 //   impl - The helper function
0037 //   device - The device type
0038 //   params - The list of formal parameters trailing the device parameter in
0039 //     the helper function's signature
0040 //   params - The list of arguments passed to the helper function, following the
0041 //     device argument
0042 //
0043 #define BOOST_IOSTREAMS_FORWARD(class, impl, device, params, args) \
0044     class(const device& t params()) \
0045     { this->impl(::boost::iostreams::detail::wrap(t) args()); } \
0046     class(device& t params()) \
0047     { this->impl(::boost::iostreams::detail::wrap(t) args()); } \
0048     class(const ::boost::reference_wrapper<device>& ref params()) \
0049     { this->impl(ref args()); } \
0050     void open(const device& t params()) \
0051     { this->impl(::boost::iostreams::detail::wrap(t) args()); } \
0052     void open(device& t params()) \
0053     { this->impl(::boost::iostreams::detail::wrap(t) args()); } \
0054     void open(const ::boost::reference_wrapper<device>& ref params()) \
0055     { this->impl(ref args()); } \
0056     BOOST_PP_REPEAT_FROM_TO( \
0057         1, BOOST_PP_INC(BOOST_IOSTREAMS_MAX_FORWARDING_ARITY), \
0058         BOOST_IOSTREAMS_FORWARDING_CTOR, (class, impl, device) \
0059     ) \
0060     BOOST_PP_REPEAT_FROM_TO( \
0061         1, BOOST_PP_INC(BOOST_IOSTREAMS_MAX_FORWARDING_ARITY), \
0062         BOOST_IOSTREAMS_FORWARDING_FN, (class, impl, device) \
0063     ) \
0064     /**/
0065 #define BOOST_IOSTREAMS_FORWARDING_CTOR(z, n, tuple) \
0066     template<BOOST_PP_ENUM_PARAMS_Z(z, n, typename U)> \
0067     BOOST_PP_TUPLE_ELEM(3, 0, tuple) \
0068     (BOOST_PP_ENUM_BINARY_PARAMS_Z(z, n, const U, &u) \
0069       BOOST_IOSTREAMS_DISABLE_IF_SAME(U0, BOOST_PP_TUPLE_ELEM(3, 2, tuple))) \
0070     { this->BOOST_PP_TUPLE_ELEM(3, 1, tuple) \
0071       ( BOOST_PP_TUPLE_ELEM(3, 2, tuple) \
0072         (BOOST_PP_ENUM_PARAMS_Z(z, n, u)) ); } \
0073     template< typename U100 BOOST_PP_COMMA_IF(BOOST_PP_DEC(n)) \
0074               BOOST_PP_ENUM_PARAMS_Z(z, BOOST_PP_DEC(n), typename U) > \
0075     BOOST_PP_TUPLE_ELEM(3, 0, tuple) \
0076     ( U100& u100 BOOST_PP_COMMA_IF(BOOST_PP_DEC(n)) \
0077       BOOST_PP_ENUM_BINARY_PARAMS_Z(z, BOOST_PP_DEC(n), const U, &u) \
0078       BOOST_IOSTREAMS_DISABLE_IF_SAME(U100, BOOST_PP_TUPLE_ELEM(3, 2, tuple))) \
0079     { this->BOOST_PP_TUPLE_ELEM(3, 1, tuple) \
0080       ( BOOST_PP_TUPLE_ELEM(3, 2, tuple) \
0081         ( u100 BOOST_PP_COMMA_IF(BOOST_PP_DEC(n)) \
0082           BOOST_PP_ENUM_PARAMS_Z(z, BOOST_PP_DEC(n), u)) ); } \
0083     /**/
0084 #define BOOST_IOSTREAMS_FORWARDING_FN(z, n, tuple) \
0085     template<BOOST_PP_ENUM_PARAMS_Z(z, n, typename U)> \
0086     void open(BOOST_PP_ENUM_BINARY_PARAMS_Z(z, n, const U, &u) \
0087       BOOST_IOSTREAMS_DISABLE_IF_SAME(U0, BOOST_PP_TUPLE_ELEM(3, 2, tuple))) \
0088     { this->BOOST_PP_TUPLE_ELEM(3, 1, tuple) \
0089       ( BOOST_PP_TUPLE_ELEM(3, 2, tuple) \
0090         (BOOST_PP_ENUM_PARAMS_Z(z, n, u)) ); } \
0091     template< typename U100 BOOST_PP_COMMA_IF(BOOST_PP_DEC(n)) \
0092               BOOST_PP_ENUM_PARAMS_Z(z, BOOST_PP_DEC(n), typename U) > \
0093     void open \
0094     ( U100& u100 BOOST_PP_COMMA_IF(BOOST_PP_DEC(n)) \
0095       BOOST_PP_ENUM_BINARY_PARAMS_Z(z, BOOST_PP_DEC(n), const U, &u) \
0096       BOOST_IOSTREAMS_DISABLE_IF_SAME(U100, BOOST_PP_TUPLE_ELEM(3, 2, tuple))) \
0097     { this->BOOST_PP_TUPLE_ELEM(3, 1, tuple) \
0098       ( u100 BOOST_PP_COMMA_IF(BOOST_PP_DEC(n)) \
0099         BOOST_PP_ENUM_PARAMS_Z(z, BOOST_PP_DEC(n), u) ); } \
0100     /**/
0101
0102 // Disable forwarding constructors if first parameter type is the same
0103 // as the device type
0104 #if !defined(BOOST_NO_SFINAE) && \
0105     !BOOST_WORKAROUND(BOOST_BORLANDC, BOOST_TESTED_AT(0x592))
0106 # define BOOST_IOSTREAMS_DISABLE_IF_SAME(device, param) \
0107     , typename boost::disable_if< boost::is_same<device, param> >::type* = 0 \
0108     /**/
0109 #else
0110 # define BOOST_IOSTREAMS_DISABLE_IF_SAME(device, param)
0111 #endif
0112
0113 #endif // #ifndef BOOST_IOSTREAMS_DETAIL_FORWARD_HPP_INCLUDED