| // Copyright (C) 2007 Peder Holt |
| |
| // Use, modification and distribution is subject to the Boost Software |
| // License, Version 1.0. (http://www.boost.org/LICENSE_1_0.txt) |
| |
| #ifndef BOOST_TYPEOF_MSVC_TYPEOF_IMPL_HPP_INCLUDED |
| # define BOOST_TYPEOF_MSVC_TYPEOF_IMPL_HPP_INCLUDED |
| |
| # include <ndnboost/config.hpp> |
| # include <ndnboost/detail/workaround.hpp> |
| # include <ndnboost/mpl/int.hpp> |
| |
| namespace ndnboost |
| { |
| namespace type_of |
| { |
| |
| template<int N> struct encode_counter : encode_counter<N - 1> {}; |
| template<> struct encode_counter<0> {}; |
| |
| char (*encode_index(...))[1]; |
| |
| # define BOOST_TYPEOF_INDEX(T) (sizeof(*ndnboost::type_of::encode_index((ndnboost::type_of::encode_counter<1000>*)0))) |
| # define BOOST_TYPEOF_NEXT_INDEX(next) friend char (*encode_index(encode_counter<next>*))[next]; |
| |
| |
| //Typeof code |
| |
| template<typename ID> |
| struct msvc_extract_type |
| { |
| struct id2type; |
| }; |
| |
| template<typename T, typename ID> |
| struct msvc_register_type : msvc_extract_type<ID> |
| { |
| typedef msvc_extract_type<ID> base_type; |
| struct base_type::id2type // This uses nice VC6.5 and VC7.1 bugfeature, also works for Digital Mars |
| { |
| typedef T type; |
| }; |
| }; |
| |
| |
| template<int ID> |
| struct msvc_typeid_wrapper { |
| typedef typename msvc_extract_type<mpl::int_<ID> >::id2type id2type; |
| typedef typename id2type::type type; |
| }; |
| |
| //Tie it all together |
| template<typename T> |
| struct encode_type |
| { |
| //Get the next available compile time constants index |
| BOOST_STATIC_CONSTANT(unsigned,value=BOOST_TYPEOF_INDEX(T)); |
| //Instantiate the template |
| typedef typename msvc_register_type<T,mpl::int_<value> >::id2type type; |
| //Set the next compile time constants index |
| BOOST_STATIC_CONSTANT(unsigned,next=value+1); |
| //Increment the compile time constant (only needed when extensions are not active |
| BOOST_TYPEOF_NEXT_INDEX(next); |
| }; |
| |
| template<class T> |
| struct sizer |
| { |
| typedef char(*type)[encode_type<T>::value]; |
| }; |
| |
| template<typename T> |
| typename sizer<T>::type encode_start(T const&); |
| |
| template<typename Organizer, typename T> |
| msvc_register_type<T,Organizer> typeof_register_type(const T&,Organizer* =0); |
| |
| # define BOOST_TYPEOF(expr) \ |
| ndnboost::type_of::msvc_typeid_wrapper<sizeof(*ndnboost::type_of::encode_start(expr))>::type |
| |
| # define BOOST_TYPEOF_TPL(expr) typename BOOST_TYPEOF(expr) |
| |
| # define BOOST_TYPEOF_NESTED_TYPEDEF_TPL(name,expr) \ |
| struct name {\ |
| BOOST_STATIC_CONSTANT(int,_typeof_register_value=sizeof(ndnboost::type_of::typeof_register_type<name>(expr)));\ |
| typedef typename ndnboost::type_of::msvc_extract_type<name>::id2type id2type;\ |
| typedef typename id2type::type type;\ |
| }; |
| |
| # define BOOST_TYPEOF_NESTED_TYPEDEF(name,expr) \ |
| struct name {\ |
| BOOST_STATIC_CONSTANT(int,_typeof_register_value=sizeof(ndnboost::type_of::typeof_register_type<name>(expr)));\ |
| typedef ndnboost::type_of::msvc_extract_type<name>::id2type id2type;\ |
| typedef id2type::type type;\ |
| }; |
| |
| } |
| } |
| |
| #endif//BOOST_TYPEOF_MSVC_TYPEOF_IMPL_HPP_INCLUDED |