1
2// Copyright 2005-2009 Daniel James.
3// Distributed under the Boost Software License, Version 1.0. (See accompanying
4// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
5
6// Based on Peter Dimov's proposal
7// http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2005/n1756.pdf
8// issue 6.18.
9
10// This implements the extensions to the standard.
11// It's undocumented, so you shouldn't use it....
12
13#if !defined(BOOST_FUNCTIONAL_HASH_EXTENSIONS_HPP)
14#define BOOST_FUNCTIONAL_HASH_EXTENSIONS_HPP
15
16#include <boost/config.hpp>
17#if defined(BOOST_HAS_PRAGMA_ONCE)
18#pragma once
19#endif
20
21#include <boost/functional/hash/hash.hpp>
22#include <boost/detail/container_fwd.hpp>
23#include <boost/utility/enable_if.hpp>
24#include <boost/static_assert.hpp>
25#include <boost/preprocessor/repetition/repeat_from_to.hpp>
26#include <boost/preprocessor/repetition/enum_params.hpp>
27
28#if !defined(BOOST_NO_CXX11_HDR_ARRAY)
29# include <array>
30#endif
31
32#if !defined(BOOST_NO_CXX11_HDR_TUPLE)
33# include <tuple>
34#endif
35
36#if !defined(BOOST_NO_CXX11_HDR_MEMORY)
37# include <memory>
38#endif
39
40#if defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
41#include <boost/type_traits/is_array.hpp>
42#endif
43
44namespace boost
45{
46 template <class A, class B>
47 std::size_t hash_value(std::pair<A, B> const&);
48 template <class T, class A>
49 std::size_t hash_value(std::vector<T, A> const&);
50 template <class T, class A>
51 std::size_t hash_value(std::list<T, A> const& v);
52 template <class T, class A>
53 std::size_t hash_value(std::deque<T, A> const& v);
54 template <class K, class C, class A>
55 std::size_t hash_value(std::set<K, C, A> const& v);
56 template <class K, class C, class A>
57 std::size_t hash_value(std::multiset<K, C, A> const& v);
58 template <class K, class T, class C, class A>
59 std::size_t hash_value(std::map<K, T, C, A> const& v);
60 template <class K, class T, class C, class A>
61 std::size_t hash_value(std::multimap<K, T, C, A> const& v);
62
63 template <class T>
64 std::size_t hash_value(std::complex<T> const&);
65
66 template <class A, class B>
67 std::size_t hash_value(std::pair<A, B> const& v)
68 {
69 std::size_t seed = 0;
70 boost::hash_combine(seed, v.first);
71 boost::hash_combine(seed, v.second);
72 return seed;
73 }
74
75 template <class T, class A>
76 std::size_t hash_value(std::vector<T, A> const& v)
77 {
78 return boost::hash_range(v.begin(), v.end());
79 }
80
81 template <class T, class A>
82 std::size_t hash_value(std::list<T, A> const& v)
83 {
84 return boost::hash_range(v.begin(), v.end());
85 }
86
87 template <class T, class A>
88 std::size_t hash_value(std::deque<T, A> const& v)
89 {
90 return boost::hash_range(v.begin(), v.end());
91 }
92
93 template <class K, class C, class A>
94 std::size_t hash_value(std::set<K, C, A> const& v)
95 {
96 return boost::hash_range(v.begin(), v.end());
97 }
98
99 template <class K, class C, class A>
100 std::size_t hash_value(std::multiset<K, C, A> const& v)
101 {
102 return boost::hash_range(v.begin(), v.end());
103 }
104
105 template <class K, class T, class C, class A>
106 std::size_t hash_value(std::map<K, T, C, A> const& v)
107 {
108 return boost::hash_range(v.begin(), v.end());
109 }
110
111 template <class K, class T, class C, class A>
112 std::size_t hash_value(std::multimap<K, T, C, A> const& v)
113 {
114 return boost::hash_range(v.begin(), v.end());
115 }
116
117 template <class T>
118 std::size_t hash_value(std::complex<T> const& v)
119 {
120 boost::hash<T> hasher;
121 std::size_t seed = hasher(v.imag());
122 seed ^= hasher(v.real()) + (seed<<6) + (seed>>2);
123 return seed;
124 }
125
126#if !defined(BOOST_NO_CXX11_HDR_ARRAY)
127 template <class T, std::size_t N>
128 std::size_t hash_value(std::array<T, N> const& v)
129 {
130 return boost::hash_range(v.begin(), v.end());
131 }
132#endif
133
134#if !defined(BOOST_NO_CXX11_HDR_TUPLE)
135 namespace hash_detail {
136 template <std::size_t I, typename T>
137 inline typename boost::enable_if_c<(I == std::tuple_size<T>::value),
138 void>::type
139 hash_combine_tuple(std::size_t&, T const&)
140 {
141 }
142
143 template <std::size_t I, typename T>
144 inline typename boost::enable_if_c<(I < std::tuple_size<T>::value),
145 void>::type
146 hash_combine_tuple(std::size_t& seed, T const& v)
147 {
148 boost::hash_combine(seed, std::get<I>(v));
149 boost::hash_detail::hash_combine_tuple<I + 1>(seed, v);
150 }
151
152 template <typename T>
153 inline std::size_t hash_tuple(T const& v)
154 {
155 std::size_t seed = 0;
156 boost::hash_detail::hash_combine_tuple<0>(seed, v);
157 return seed;
158 }
159 }
160
161#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
162 template <typename... T>
163 inline std::size_t hash_value(std::tuple<T...> const& v)
164 {
165 return boost::hash_detail::hash_tuple(v);
166 }
167#else
168
169 inline std::size_t hash_value(std::tuple<> const& v)
170 {
171 return boost::hash_detail::hash_tuple(v);
172 }
173
174# define BOOST_HASH_TUPLE_F(z, n, _) \
175 template< \
176 BOOST_PP_ENUM_PARAMS_Z(z, n, typename A) \
177 > \
178 inline std::size_t hash_value(std::tuple< \
179 BOOST_PP_ENUM_PARAMS_Z(z, n, A) \
180 > const& v) \
181 { \
182 return boost::hash_detail::hash_tuple(v); \
183 }
184
185 BOOST_PP_REPEAT_FROM_TO(1, 11, BOOST_HASH_TUPLE_F, _)
186# undef BOOST_HASH_TUPLE_F
187#endif
188
189#endif
190
191#if !defined(BOOST_NO_CXX11_SMART_PTR)
192 template <typename T>
193 inline std::size_t hash_value(std::shared_ptr<T> const& x) {
194 return boost::hash_value(x.get());
195 }
196
197 template <typename T, typename Deleter>
198 inline std::size_t hash_value(std::unique_ptr<T, Deleter> const& x) {
199 return boost::hash_value(x.get());
200 }
201#endif
202
203 //
204 // call_hash_impl
205 //
206
207 // On compilers without function template ordering, this deals with arrays.
208
209#if defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
210 namespace hash_detail
211 {
212 template <bool IsArray>
213 struct call_hash_impl
214 {
215 template <class T>
216 struct inner
217 {
218 static std::size_t call(T const& v)
219 {
220 using namespace boost;
221 return hash_value(v);
222 }
223 };
224 };
225
226 template <>
227 struct call_hash_impl<true>
228 {
229 template <class Array>
230 struct inner
231 {
232 static std::size_t call(Array const& v)
233 {
234 const int size = sizeof(v) / sizeof(*v);
235 return boost::hash_range(v, v + size);
236 }
237 };
238 };
239
240 template <class T>
241 struct call_hash
242 : public call_hash_impl<boost::is_array<T>::value>
243 ::BOOST_NESTED_TEMPLATE inner<T>
244 {
245 };
246 }
247#endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
248
249 //
250 // boost::hash
251 //
252
253
254#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
255
256 template <class T> struct hash
257 : std::unary_function<T, std::size_t>
258 {
259#if !defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
260 std::size_t operator()(T const& val) const
261 {
262 return hash_value(val);
263 }
264#else
265 std::size_t operator()(T const& val) const
266 {
267 return hash_detail::call_hash<T>::call(val);
268 }
269#endif
270 };
271
272#if BOOST_WORKAROUND(__DMC__, <= 0x848)
273 template <class T, unsigned int n> struct hash<T[n]>
274 : std::unary_function<T[n], std::size_t>
275 {
276 std::size_t operator()(const T* val) const
277 {
278 return boost::hash_range(val, val+n);
279 }
280 };
281#endif
282
283#else // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
284
285 // On compilers without partial specialization, boost::hash<T>
286 // has already been declared to deal with pointers, so just
287 // need to supply the non-pointer version of hash_impl.
288
289 namespace hash_detail
290 {
291 template <bool IsPointer>
292 struct hash_impl;
293
294 template <>
295 struct hash_impl<false>
296 {
297 template <class T>
298 struct inner
299 : std::unary_function<T, std::size_t>
300 {
301#if !defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
302 std::size_t operator()(T const& val) const
303 {
304 return hash_value(val);
305 }
306#else
307 std::size_t operator()(T const& val) const
308 {
309 return hash_detail::call_hash<T>::call(val);
310 }
311#endif
312 };
313 };
314 }
315#endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
316}
317
318#endif
319