EVOLUTION-MANAGER

Edit File: perfect_fwd.hpp

/* Copyright 2006-2014 Joaquin M Lopez Munoz. * 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/flyweight for library home page. */ #ifndef BOOST_FLYWEIGHT_DETAIL_PERFECT_FWD_HPP #define BOOST_FLYWEIGHT_DETAIL_PERFECT_FWD_HPP #if defined(_MSC_VER) #pragma once #endif /* C++03-compatible implementation of perfect forwarding. * Usage: * * # define NAME ... * # define BODY(args) {...BOOST_FLYWEIGHT_FORWARD(args)...} * BOOST_FLYWEIGHT_PERFECT_FWD(name,body) * * where NAME includes the return type and qualifiers (if any) and BODY(args) * is expected to fo the forwarding through BOOST_FLYWEIGHT_FORWARD(args). * * In compilers capable of perfect forwarding, the real thing is provided * (just one variadic args overload is generated). Otherwise the machinery * generates n+1 overloads, if rvalue refs are supported, or else 2^(n+1)-1 * overloads accepting any combination of lvalue refs and const lvalue refs, * up to BOOST_FLYWEIGHT_LIMIT_PERFECT_FWD_ARGS args. * * BOOST_FLYWEIGHT_PERFECT_FWD_WITH_ARGS(name,body) is a variation omitting the * overloads with zero args --when perfect forwarding is available, this second * macro is exactly the same as the original. */ #include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */ #include <boost/preprocessor/cat.hpp> #include <boost/preprocessor/repetition/enum.hpp> #include <boost/preprocessor/repetition/enum_params.hpp> #include <boost/preprocessor/seq/seq.hpp> #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) #include <utility> #endif #define BOOST_FLYWEIGHT_FORWARD_FORWARD_AUX(z,n,_) \ std::forward<BOOST_PP_CAT(T,n)>(BOOST_PP_CAT(t,n)) #define BOOST_FLYWEIGHT_FORWARD_FORWARD(n) \ BOOST_PP_ENUM(n,BOOST_FLYWEIGHT_FORWARD_FORWARD_AUX,~) #define BOOST_FLYWEIGHT_FORWARD_ENUM(n) BOOST_PP_ENUM_PARAMS(n,t) #define BOOST_FLYWEIGHT_FORWARD_PASS(arg) arg #define BOOST_FLYWEIGHT_FORWARD(args)\ BOOST_PP_CAT(BOOST_FLYWEIGHT_FORWARD_,BOOST_PP_SEQ_HEAD(args))( \ BOOST_PP_SEQ_HEAD(BOOST_PP_SEQ_TAIL(args))) #if defined(BOOST_NO_CXX11_RVALUE_REFERENCES)||\ defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) #if !defined(BOOST_FLYWEIGHT_LIMIT_PERFECT_FWD_ARGS) #define BOOST_FLYWEIGHT_LIMIT_PERFECT_FWD_ARGS 5 #endif #if BOOST_FLYWEIGHT_LIMIT_PERFECT_FWD_ARGS<0 #error BOOST_FLYWEIGHT_LIMIT_PERFECT_FWD_ARGS must be >=0 #endif #if BOOST_FLYWEIGHT_LIMIT_PERFECT_FWD_ARGS<=5 #include <boost/flyweight/detail/pp_perfect_fwd.hpp> #else #include <boost/flyweight/detail/dyn_perfect_fwd.hpp> #endif #else /* real perfect forwarding */ #define BOOST_FLYWEIGHT_PERFECT_FWD(name,body) \ template<typename... Args>name(Args&&... args) \ body((PASS)(std::forward<Args>(args)...)) #define BOOST_FLYWEIGHT_PERFECT_FWD_WITH_ARGS \ BOOST_FLYWEIGHT_PERFECT_FWD #endif #endif