]>
Commit | Line | Data |
---|---|---|
7c673cae FG |
1 | // Copyright (C) 2007 Peder Holt |
2 | ||
3 | // Use, modification and distribution is subject to the Boost Software | |
4 | // License, Version 1.0. (http://www.boost.org/LICENSE_1_0.txt) | |
5 | ||
6 | #ifndef BOOST_TYPEOF_MSVC_TYPEOF_IMPL_HPP_INCLUDED | |
7 | # define BOOST_TYPEOF_MSVC_TYPEOF_IMPL_HPP_INCLUDED | |
8 | ||
9 | # include <boost/config.hpp> | |
10 | # include <boost/detail/workaround.hpp> | |
11 | # include <boost/mpl/int.hpp> | |
12 | ||
13 | namespace boost | |
14 | { | |
15 | namespace type_of | |
16 | { | |
17 | ||
18 | template<int N> struct encode_counter : encode_counter<N - 1> {}; | |
19 | template<> struct encode_counter<0> {}; | |
20 | ||
21 | char (*encode_index(...))[1]; | |
22 | ||
23 | # define BOOST_TYPEOF_INDEX(T) (sizeof(*boost::type_of::encode_index((boost::type_of::encode_counter<1000>*)0))) | |
24 | # define BOOST_TYPEOF_NEXT_INDEX(next) friend char (*encode_index(encode_counter<next>*))[next]; | |
25 | ||
26 | ||
27 | //Typeof code | |
28 | ||
29 | template<typename ID> | |
30 | struct msvc_extract_type | |
31 | { | |
32 | struct id2type; | |
33 | }; | |
34 | ||
35 | template<typename T, typename ID> | |
36 | struct msvc_register_type : msvc_extract_type<ID> | |
37 | { | |
38 | typedef msvc_extract_type<ID> base_type; | |
39 | struct base_type::id2type // This uses nice VC6.5 and VC7.1 bugfeature, also works for Digital Mars | |
40 | { | |
41 | typedef T type; | |
42 | }; | |
43 | }; | |
44 | ||
45 | ||
46 | template<int ID> | |
47 | struct msvc_typeid_wrapper { | |
48 | typedef typename msvc_extract_type<mpl::int_<ID> >::id2type id2type; | |
49 | typedef typename id2type::type type; | |
50 | }; | |
51 | ||
52 | //Tie it all together | |
53 | template<typename T> | |
54 | struct encode_type | |
55 | { | |
56 | //Get the next available compile time constants index | |
57 | BOOST_STATIC_CONSTANT(unsigned,value=BOOST_TYPEOF_INDEX(T)); | |
58 | //Instantiate the template | |
59 | typedef typename msvc_register_type<T,mpl::int_<value> >::id2type type; | |
60 | //Set the next compile time constants index | |
61 | BOOST_STATIC_CONSTANT(unsigned,next=value+1); | |
62 | //Increment the compile time constant (only needed when extensions are not active | |
63 | BOOST_TYPEOF_NEXT_INDEX(next); | |
64 | }; | |
65 | ||
66 | template<class T> | |
67 | struct sizer | |
68 | { | |
69 | typedef char(*type)[encode_type<T>::value]; | |
70 | }; | |
71 | ||
72 | template<typename T> | |
73 | typename sizer<T>::type encode_start(T const&); | |
74 | ||
75 | template<typename Organizer, typename T> | |
76 | msvc_register_type<T,Organizer> typeof_register_type(const T&,Organizer* =0); | |
77 | ||
78 | # define BOOST_TYPEOF(expr) \ | |
79 | boost::type_of::msvc_typeid_wrapper<sizeof(*boost::type_of::encode_start(expr))>::type | |
80 | ||
81 | # define BOOST_TYPEOF_TPL(expr) typename BOOST_TYPEOF(expr) | |
82 | ||
83 | # define BOOST_TYPEOF_NESTED_TYPEDEF_TPL(name,expr) \ | |
84 | struct name {\ | |
85 | BOOST_STATIC_CONSTANT(int,_typeof_register_value=sizeof(boost::type_of::typeof_register_type<name>(expr)));\ | |
86 | typedef typename boost::type_of::msvc_extract_type<name>::id2type id2type;\ | |
87 | typedef typename id2type::type type;\ | |
88 | }; | |
89 | ||
90 | # define BOOST_TYPEOF_NESTED_TYPEDEF(name,expr) \ | |
91 | struct name {\ | |
92 | BOOST_STATIC_CONSTANT(int,_typeof_register_value=sizeof(boost::type_of::typeof_register_type<name>(expr)));\ | |
93 | typedef boost::type_of::msvc_extract_type<name>::id2type id2type;\ | |
94 | typedef id2type::type type;\ | |
95 | }; | |
96 | ||
97 | } | |
98 | } | |
99 | ||
100 | #endif//BOOST_TYPEOF_MSVC_TYPEOF_IMPL_HPP_INCLUDED |