Merge c:/dyninst/pc_bluegene/dyninst into dyn_pc_integration
[dyninst.git] / external / boost / mpl / aux_ / begin_end_impl.hpp
1
2 #ifndef BOOST_MPL_AUX_BEGIN_END_IMPL_HPP_INCLUDED
3 #define BOOST_MPL_AUX_BEGIN_END_IMPL_HPP_INCLUDED
4
5 // Copyright Aleksey Gurtovoy 2000-2004
6 //
7 // Distributed under the Boost Software License, Version 1.0.
8 // (See accompanying file LICENSE_1_0.txt or copy at 
9 // http://www.boost.org/LICENSE_1_0.txt)
10 //
11 // See http://www.boost.org/libs/mpl for documentation.
12
13 // $Id: begin_end_impl.hpp 49267 2008-10-11 06:19:02Z agurtovoy $
14 // $Date: 2008-10-11 02:19:02 -0400 (Sat, 11 Oct 2008) $
15 // $Revision: 49267 $
16
17 #include <boost/mpl/begin_end_fwd.hpp>
18 #include <boost/mpl/sequence_tag_fwd.hpp>
19 #include <boost/mpl/void.hpp>
20 #include <boost/mpl/eval_if.hpp>
21 #include <boost/mpl/aux_/has_begin.hpp>
22 #include <boost/mpl/aux_/na.hpp>
23 #include <boost/mpl/aux_/traits_lambda_spec.hpp>
24 #include <boost/mpl/aux_/config/eti.hpp>
25
26 namespace boost { namespace mpl {
27
28
29 namespace aux { 
30
31 template< typename Sequence > 
32 struct begin_type 
33
34     typedef typename Sequence::begin type; 
35 };
36 template< typename Sequence > 
37 struct end_type
38
39     typedef typename Sequence::end type; 
40 };
41
42 }
43
44 // default implementation; conrete sequences might override it by 
45 // specializing either the 'begin_impl/end_impl' or the primary 
46 // 'begin/end' templates
47
48 template< typename Tag >
49 struct begin_impl
50 {
51     template< typename Sequence > struct apply
52     {
53         typedef typename eval_if<aux::has_begin<Sequence, true_>,
54                                  aux::begin_type<Sequence>, void_>::type type;
55     };
56 };
57
58 template< typename Tag >
59 struct end_impl
60 {
61     template< typename Sequence > struct apply
62     {
63         typedef typename eval_if<aux::has_begin<Sequence, true_>,
64                                  aux::end_type<Sequence>, void_>::type type;
65     };
66 };
67
68 // specialize 'begin_trait/end_trait' for two pre-defined tags
69
70 #   define AUX778076_IMPL_SPEC(name, tag, result) \
71 template<> \
72 struct name##_impl<tag> \
73 { \
74     template< typename Sequence > struct apply \
75     { \
76         typedef result type; \
77     }; \
78 }; \
79 /**/
80
81 // a sequence with nested 'begin/end' typedefs; just query them
82 AUX778076_IMPL_SPEC(begin, nested_begin_end_tag, typename Sequence::begin)
83 AUX778076_IMPL_SPEC(end, nested_begin_end_tag, typename Sequence::end)
84
85 // if a type 'T' does not contain 'begin/end' or 'tag' members 
86 // and doesn't specialize either 'begin/end' or 'begin_impl/end_impl' 
87 // templates, then we end up here
88 AUX778076_IMPL_SPEC(begin, non_sequence_tag, void_)
89 AUX778076_IMPL_SPEC(end, non_sequence_tag, void_)
90 AUX778076_IMPL_SPEC(begin, na, void_)
91 AUX778076_IMPL_SPEC(end, na, void_)
92
93 #   undef AUX778076_IMPL_SPEC
94
95
96 BOOST_MPL_ALGORITM_TRAITS_LAMBDA_SPEC_IMPL(1,begin_impl)
97 BOOST_MPL_ALGORITM_TRAITS_LAMBDA_SPEC_IMPL(1,end_impl)
98
99 }}
100
101 #endif // BOOST_MPL_AUX_BEGIN_END_IMPL_HPP_INCLUDED