1 | |
2 | #ifndef BOOST_MPL_LOWER_BOUND_HPP_INCLUDED |
3 | #define BOOST_MPL_LOWER_BOUND_HPP_INCLUDED |
4 | |
5 | // Copyright Aleksey Gurtovoy 2001-2004 |
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 | // $Id$ |
14 | // $Date$ |
15 | // $Revision$ |
16 | |
17 | #include <boost/mpl/less.hpp> |
18 | #include <boost/mpl/lambda.hpp> |
19 | #include <boost/mpl/aux_/na_spec.hpp> |
20 | #include <boost/mpl/aux_/config/workaround.hpp> |
21 | |
22 | #if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x610)) |
23 | # define BOOST_MPL_CFG_STRIPPED_DOWN_LOWER_BOUND_IMPL |
24 | #endif |
25 | |
26 | #if !defined(BOOST_MPL_CFG_STRIPPED_DOWN_LOWER_BOUND_IMPL) |
27 | # include <boost/mpl/minus.hpp> |
28 | # include <boost/mpl/divides.hpp> |
29 | # include <boost/mpl/size.hpp> |
30 | # include <boost/mpl/advance.hpp> |
31 | # include <boost/mpl/begin_end.hpp> |
32 | # include <boost/mpl/long.hpp> |
33 | # include <boost/mpl/eval_if.hpp> |
34 | # include <boost/mpl/prior.hpp> |
35 | # include <boost/mpl/deref.hpp> |
36 | # include <boost/mpl/apply.hpp> |
37 | # include <boost/mpl/aux_/value_wknd.hpp> |
38 | #else |
39 | # include <boost/mpl/not.hpp> |
40 | # include <boost/mpl/find.hpp> |
41 | # include <boost/mpl/bind.hpp> |
42 | #endif |
43 | |
44 | #include <boost/config.hpp> |
45 | |
46 | namespace boost { namespace mpl { |
47 | |
48 | #if defined(BOOST_MPL_CFG_STRIPPED_DOWN_LOWER_BOUND_IMPL) |
49 | |
50 | // agurt 23/oct/02: has a wrong complexity etc., but at least it works |
51 | // feel free to contribute a better implementation! |
52 | template< |
53 | typename BOOST_MPL_AUX_NA_PARAM(Sequence) |
54 | , typename BOOST_MPL_AUX_NA_PARAM(T) |
55 | , typename Predicate = less<> |
56 | , typename pred_ = typename lambda<Predicate>::type |
57 | > |
58 | struct lower_bound |
59 | : find_if< Sequence, bind1< not_<>, bind2<pred_,_,T> > > |
60 | { |
61 | }; |
62 | |
63 | #else |
64 | |
65 | namespace aux { |
66 | |
67 | template< |
68 | typename Distance |
69 | , typename Predicate |
70 | , typename T |
71 | , typename DeferredIterator |
72 | > |
73 | struct lower_bound_step_impl; |
74 | |
75 | template< |
76 | typename Distance |
77 | , typename Predicate |
78 | , typename T |
79 | , typename DeferredIterator |
80 | > |
81 | struct lower_bound_step |
82 | { |
83 | typedef typename eval_if< |
84 | Distance |
85 | , lower_bound_step_impl<Distance,Predicate,T,DeferredIterator> |
86 | , DeferredIterator |
87 | >::type type; |
88 | }; |
89 | |
90 | template< |
91 | typename Distance |
92 | , typename Predicate |
93 | , typename T |
94 | , typename DeferredIterator |
95 | > |
96 | struct lower_bound_step_impl |
97 | { |
98 | typedef typename divides< Distance, long_<2> >::type offset_; |
99 | typedef typename DeferredIterator::type iter_; |
100 | typedef typename advance< iter_,offset_ >::type middle_; |
101 | typedef typename apply2< |
102 | Predicate |
103 | , typename deref<middle_>::type |
104 | , T |
105 | >::type cond_; |
106 | |
107 | typedef typename prior< minus< Distance, offset_> >::type step_; |
108 | typedef lower_bound_step< offset_,Predicate,T,DeferredIterator > step_forward_; |
109 | typedef lower_bound_step< step_,Predicate,T,next<middle_> > step_backward_; |
110 | typedef typename eval_if< |
111 | cond_ |
112 | , step_backward_ |
113 | , step_forward_ |
114 | >::type type; |
115 | }; |
116 | |
117 | |
118 | } // namespace aux |
119 | |
120 | template< |
121 | typename BOOST_MPL_AUX_NA_PARAM(Sequence) |
122 | , typename BOOST_MPL_AUX_NA_PARAM(T) |
123 | , typename Predicate = less<> |
124 | > |
125 | struct lower_bound |
126 | { |
127 | private: |
128 | typedef typename lambda<Predicate>::type pred_; |
129 | typedef typename size<Sequence>::type size_; |
130 | |
131 | public: |
132 | typedef typename aux::lower_bound_step< |
133 | size_,pred_,T,begin<Sequence> |
134 | >::type type; |
135 | }; |
136 | |
137 | #endif // BOOST_MPL_CFG_STRIPPED_DOWN_LOWER_BOUND_IMPL |
138 | |
139 | BOOST_MPL_AUX_NA_SPEC(2, lower_bound) |
140 | |
141 | }} |
142 | |
143 | #endif // BOOST_MPL_LOWER_BOUND_HPP_INCLUDED |
144 | |