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6 | <title>Boost.MultiIndex Documentation - Key extraction reference</title> | |
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15 | <h1><img src="../../../../boost.png" alt="boost.png (6897 bytes)" align= | |
16 | "middle" width="277" height="86">Boost.MultiIndex Key extraction reference</h1> | |
17 | ||
18 | <div class="prev_link"><a href="rnd_indices.html"><img src="../prev.gif" alt="random access indices" border="0"><br> | |
19 | Random access indices | |
20 | </a></div> | |
21 | <div class="up_link"><a href="index.html"><img src="../up.gif" alt="Boost.MultiIndex reference" border="0"><br> | |
22 | Boost.MultiIndex reference | |
23 | </a></div> | |
24 | <div class="next_link"><a href="../compiler_specifics.html"><img src="../next.gif" alt="compiler specifics" border="0"><br> | |
25 | Compiler specifics | |
26 | </a></div><br clear="all" style="clear: all;"> | |
27 | ||
28 | <hr> | |
29 | ||
30 | <h2>Contents</h2> | |
31 | ||
32 | <ul> | |
33 | <li><a href="#key_extractors">Key Extractors</a> | |
34 | <ul> | |
35 | <li><a href="#chained_pointers">Chained pointers</a></li> | |
36 | </ul> | |
37 | </li> | |
38 | <li><a href="#synopsis">Header | |
39 | <code>"boost/multi_index/key_extractors.hpp"</code> synopsis</a> | |
40 | </li> | |
41 | <li><a href="#identity_synopsis">Header | |
42 | <code>"boost/multi_index/identity.hpp"</code> synopsis</a> | |
43 | <ul> | |
44 | <li><a href="#identity">Class template <code>identity</code></a></li> | |
45 | </ul> | |
46 | </li> | |
47 | <li><a href="#member_synopsis">Header | |
48 | <code>"boost/multi_index/member.hpp"</code> synopsis</a> | |
49 | <ul> | |
50 | <li><a href="#member">Class template <code>member</code></a></li> | |
51 | <li><a href="#member_offset">Class template <code>member_offset</code></a></li> | |
52 | <li><a href="#boost_multi_index_member">Macro <code>BOOST_MULTI_INDEX_MEMBER</code></a></li> | |
53 | </ul> | |
54 | </li> | |
55 | <li><a href="#mem_fun_synopsis">Header | |
56 | <code>"boost/multi_index/mem_fun.hpp"</code> synopsis</a> | |
57 | <ul> | |
58 | <li><a href="#const_mem_fun">Class template <code>const_mem_fun</code></a></li> | |
59 | <li><a href="#mem_fun">Class template <code>mem_fun</code></a></li> | |
60 | <li><a href="#const_mem_fun_explicit">Class templates <code>const_mem_fun_explicit</code> and <code>mem_fun_explicit</code></a></li> | |
61 | <li><a href="#boost_multi_index_const_mem_fun">Macros <code>BOOST_MULTI_INDEX_CONST_MEM_FUN</code> and <code>BOOST_MULTI_INDEX_MEM_FUN</code></a></li> | |
62 | </ul> | |
63 | </li> | |
64 | <li><a href="#global_fun_synopsis">Header | |
65 | <code>"boost/multi_index/global_fun.hpp"</code> synopsis</a> | |
66 | <ul> | |
67 | <li><a href="#global_fun">Class template <code>global_fun</code></a></li> | |
68 | </ul> | |
69 | </li> | |
70 | <li><a href="#composite_key_synopsis">Header | |
71 | <code>"boost/multi_index/composite_key.hpp"</code> synopsis</a> | |
72 | <ul> | |
73 | <li><a href="#composite_key">Class template <code>composite_key</code></a></li> | |
74 | <li><a href="#composite_key_result">Class template <code>composite_key_result</code></a></li> | |
75 | <li><a href="#ckey_result_equality">Equality</a> | |
76 | <ul> | |
77 | <li><a href="#composite_key_equal_to">Class template <code>composite_key_equal_to</code></a></li> | |
78 | <li><a href="#composite_key_result_equal_to">Class template <code>composite_key_result_equal_to</code></a></li> | |
79 | <li><a href="#equal_to_composite_key_result">Specialization of <code>std::equal_to</code> for <code>composite_key</code> results</a></li> | |
80 | </ul> | |
81 | </li> | |
82 | <li><a href="#ckey_result_comparison">Comparison</a> | |
83 | <ul> | |
84 | <li><a href="#composite_key_compare">Class template <code>composite_key_compare</code></a></li> | |
85 | <li><a href="#composite_key_result_less">Class template <code>composite_key_result_less</code></a></li> | |
86 | <li><a href="#composite_key_result_greater">Class template <code>composite_key_result_greater</code></a></li> | |
87 | <li><a href="#less_composite_key_result">Specialization of <code>std::less</code> for <code>composite_key</code> results</a></li> | |
88 | <li><a href="#greater_composite_key_result">Specialization of <code>std::greater</code> for <code>composite_key</code> results</a></li> | |
89 | </ul> | |
90 | </li> | |
91 | <li><a href="#ckey_result_hashing">Hashing</a> | |
92 | <ul> | |
93 | <li><a href="#composite_key_hash">Class template <code>composite_key_hash</code></a></li> | |
94 | <li><a href="#composite_key_result_hash">Class template <code>composite_key_result_hash</code></a></li> | |
95 | <li><a href="#hash_composite_key_result">Specialization of <code>boost::hash</code> for <code>composite_key</code> results</a></li> | |
96 | </ul> | |
97 | </li> | |
98 | <li><a href="#ckey_result_semantics">Semantics of <code>composite_key_result</code></a></li> | |
99 | </ul> | |
100 | </li> | |
101 | </ul> | |
102 | ||
103 | <h2><a name="key_extractors">Key Extractors</a></h2> | |
104 | ||
105 | <p> | |
106 | Key extraction classes are used by | |
107 | <a href="indices.html#key_based_indices">key-based indices</a> to | |
108 | obtain the indexing keys from the elements of a <code>multi_index_container</code>. | |
109 | A <code>CopyConstructible</code> and <code>CopyAssignable</code> | |
110 | class <code>KeyFromValue</code> is said to be a key extractor from a | |
111 | type <code>Type</code> if | |
112 | <ol> | |
113 | <li>the type <code>KeyFromValue::result_type</code> is defined,</li> | |
114 | <li><code>k1(ca)</code> is defined and returns a value convertible | |
115 | to <code>const KeyFromValue::result_type&</code>,</li> | |
116 | <li>if <code>k2</code> is a copy of <code>k1</code>, <code>k1(ca)</code> is the | |
117 | same value as <code>k2(ca)</code>,</li> | |
118 | </ol> | |
119 | for every <code>k1</code>, <code>k2</code> of type <code>const KeyFromValue</code>, | |
120 | and <code>ca</code> of type <code>const Type&</code>. | |
121 | </p> | |
122 | ||
123 | <p> | |
124 | Additionally, <code>KeyFromValue</code> is a <i>read/write</i> key extractor | |
125 | if the following extra conditions are met: | |
126 | <ol> | |
127 | <li><code>k1(a)</code> is defined and returns a value convertible | |
128 | to <code>KeyFromValue::result_type&</code>,</li> | |
129 | <li><code>const_cast<const KeyFromValue::result_type&>(k1(a))</code> | |
130 | is the same value as | |
131 | <code>k1(const_cast<const Type&>(a))</code>,</li> | |
132 | </ol> | |
133 | for every <code>k1</code> of type <code>const KeyFromValue</code> and | |
134 | <code>a</code> of type <code>Type&</code>. | |
135 | </p> | |
136 | ||
137 | <p> | |
138 | Boost.MultiIndex provides six general-purpose key extractors: | |
139 | <ul> | |
140 | <li><a href="#identity"><code>identity</code></a>,</li> | |
141 | <li><a href="#member"><code>member</code></a>,</li> | |
142 | <li><a href="#const_mem_fun"><code>const_mem_fun</code></a>,</li> | |
143 | <li><a href="#mem_fun"><code>mem_fun</code></a>,</li> | |
144 | <li><a href="#global_fun"><code>global_fun</code></a> and</li> | |
145 | <li><a href="#composite_key"><code>composite_key</code></a>.</li> | |
146 | </ul> | |
147 | </p> | |
148 | ||
149 | <h3><a name="chained_pointers">Chained pointers</a></h3> | |
150 | ||
151 | <p> | |
152 | The key extractors provided by Boost.MultiIndex are templatized according | |
153 | to the type <code>Type</code> and serve to extract keys not only from objects | |
154 | of type <code>Type</code>, but also from reference wrappers provided by | |
155 | <a href="../../../../doc/html/ref.html">Boost.Ref</a> and from <i>chained pointers</i> | |
156 | to <code>Type</code> (or to reference wrappers of <code>Type</code>): a chained pointer | |
157 | is any type <code>P</code> such that, for an object <code>p</code> of type | |
158 | <code>const P</code> | |
159 | <ul> | |
160 | <li><code>*p</code> yields an object of type <code>Type&</code> or | |
161 | <code>boost::reference_wrapper<Type></code>, OR</li> | |
162 | <li><code>*p</code> yields a chained pointer to <code>Type</code>,</li> | |
163 | </ul> | |
164 | that is, chained pointers are arbitrary compositions of pointer-like objects | |
165 | ultimately dereferencing to values of <code>Type&</code> or | |
166 | <code>boost::reference_wrapper<Type></code>. | |
167 | <p> | |
168 | ||
169 | <h2><a name="synopsis">Header | |
170 | <a href="../../../../boost/multi_index/key_extractors.hpp"> | |
171 | <code>"boost/multi_index/key_extractors.hpp"</code></a> synopsis</a> | |
172 | </h2> | |
173 | ||
174 | <blockquote><pre> | |
175 | <span class=preprocessor>#include</span> <span class=special><</span><span class=identifier>boost</span><span class=special>/</span><span class=identifier>multi_index</span><span class=special>/</span><span class=identifier>identity</span><span class=special>.</span><span class=identifier>hpp</span><span class=special>></span> | |
176 | <span class=preprocessor>#include</span> <span class=special><</span><span class=identifier>boost</span><span class=special>/</span><span class=identifier>multi_index</span><span class=special>/</span><span class=identifier>member</span><span class=special>.</span><span class=identifier>hpp</span><span class=special>></span> | |
177 | <span class=preprocessor>#include</span> <span class=special><</span><span class=identifier>boost</span><span class=special>/</span><span class=identifier>multi_index</span><span class=special>/</span><span class=identifier>mem_fun</span><span class=special>.</span><span class=identifier>hpp</span><span class=special>></span> | |
178 | <span class=preprocessor>#include</span> <span class=special><</span><span class=identifier>boost</span><span class=special>/</span><span class=identifier>multi_index</span><span class=special>/</span><span class=identifier>global_fun</span><span class=special>.</span><span class=identifier>hpp</span><span class=special>></span> | |
179 | <span class=preprocessor>#include</span> <span class=special><</span><span class=identifier>boost</span><span class=special>/</span><span class=identifier>multi_index</span><span class=special>/</span><span class=identifier>composite_key</span><span class=special>.</span><span class=identifier>hpp</span><span class=special>></span> | |
180 | </pre></blockquote> | |
181 | ||
182 | <p> | |
183 | This header includes all the key extractors provided by Boost.MultiIndex. | |
184 | </p> | |
185 | ||
186 | <h2> | |
187 | <a name="identity_synopsis">Header | |
188 | <a href="../../../../boost/multi_index/identity.hpp"> | |
189 | <code>"boost/multi_index/identity.hpp"</code></a> synopsis</a></h2> | |
190 | ||
191 | <blockquote><pre> | |
192 | <span class=keyword>namespace</span> <span class=identifier>boost</span><span class=special>{</span> | |
193 | ||
194 | <span class=keyword>namespace</span> <span class=identifier>multi_index</span><span class=special>{</span> | |
195 | ||
196 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>T</span><span class=special>></span> <span class=keyword>struct</span> <span class=identifier>identity</span><span class=special>;</span> | |
197 | ||
198 | <span class=special>}</span> <span class=comment>// namespace boost::multi_index</span> | |
199 | ||
200 | <span class=special>}</span> <span class=comment>// namespace boost</span> | |
201 | </pre></blockquote> | |
202 | ||
203 | <h3><a name="identity">Class template <code>identity</code></a></h3> | |
204 | ||
205 | <p> | |
206 | <code>identity</code> is a <a href="#key_extractors"><code>Key Extractor</code></a> | |
207 | that acts as a do-nothing identity functor. | |
208 | </p> | |
209 | ||
210 | <blockquote><pre> | |
211 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Type</span><span class=special>></span> | |
212 | <span class=keyword>struct</span> <span class=identifier>identity</span> | |
213 | <span class=special>{</span> | |
214 | <span class=keyword>typedef</span> <span class=identifier>Type</span> <span class=identifier>result_type</span><span class=special>;</span> | |
215 | ||
216 | <span class=comment>// only provided if const ChainedPtr& is not convertible to const Type&</span> | |
217 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>ChainedPtr</span><span class=special>></span> <span class=identifier>Type</span><span class=special>&</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>ChainedPtr</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
218 | ||
219 | <span class=keyword>const</span> <span class=identifier>Type</span><span class=special>&</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>Type</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
220 | <span class=identifier>Type</span><span class=special>&</span> <span class=keyword>operator</span><span class=special>()(</span><span class=identifier>Type</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> <span class=comment>// only provided if Type is non-const | |
221 | ||
222 | // only provided if Type is non-const</span> | |
223 | <span class=keyword>const</span> <span class=identifier>Type</span><span class=special>&</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span><span class=keyword>const</span> <span class=identifier>Type</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
224 | ||
225 | <span class=comment>// only provided if Type is const</span> | |
226 | <span class=identifier>Type</span><span class=special>&</span> <span class=keyword>operator</span><span class=special>()(</span> | |
227 | <span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>remove_const</span><span class=special><</span><span class=identifier>Type</span><span class=special>>::</span><span class=identifier>type</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
228 | ||
229 | <span class=identifier>Type</span><span class=special>&</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span><span class=identifier>Type</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
230 | <span class=special>};</span> | |
231 | </pre></blockquote> | |
232 | ||
233 | <p> | |
234 | <code>identity<Type></code> is a model of: | |
235 | <ul> | |
236 | <li>read/write <a href="#key_extractors"><code>Key Extractor</code></a> | |
237 | from <code>Type</code>,</li> | |
238 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
239 | from <code>reference_wrapper<const Type></code>,</li> | |
240 | <li>read/write <a href="#key_extractors"><code>Key Extractor</code></a> | |
241 | from <code>reference_wrapper<Type></code>,</li> | |
242 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
243 | from any <a href="#chained_pointers">chained pointer</a> to | |
244 | <code>const Type</code>,</li> | |
245 | <li>read/write <a href="#key_extractors"><code>Key Extractor</code></a> | |
246 | from any <a href="#chained_pointers">chained pointer</a> | |
247 | to <code>Type</code>.</li> | |
248 | </ul> | |
249 | </p> | |
250 | ||
251 | <h4><code>identity</code> members</h4> | |
252 | ||
253 | <code>template<typename ChainedPtr> Type& operator()(const ChainedPtr& x)const;</code> | |
254 | ||
255 | <blockquote> | |
256 | <b>Requires:</b> <code>ChainedPtr</code> is a <a href="#chained_pointers">chained pointer</a> | |
257 | type to <code>Type</code>.<br> | |
258 | <b>Returns:</b> a reference to the object chained-pointed to by <code>x</code>. | |
259 | </blockquote> | |
260 | ||
261 | <code>const Type& operator()(const Type& x)const;</code> | |
262 | ||
263 | <blockquote> | |
264 | <b>Returns:</b> <code>x</code>. | |
265 | </blockquote> | |
266 | ||
267 | <code>Type& operator()(Type& x)const;</code> | |
268 | ||
269 | <blockquote> | |
270 | <b>Returns:</b> <code>x</code>. | |
271 | </blockquote> | |
272 | ||
273 | <code>const Type& operator()(const reference_wrapper<const Type>& x)const;</code> | |
274 | <blockquote> | |
275 | <b>Returns:</b> <code>x.get()</code>. | |
276 | </blockquote> | |
277 | ||
278 | <code>Type& operator()(const reference_wrapper<typename remove_const<Type>::type>& x)const;</code> | |
279 | <blockquote> | |
280 | <b>Returns:</b> <code>x.get()</code>. | |
281 | </blockquote> | |
282 | ||
283 | <code>Type& operator()(const reference_wrapper<Type>& x)const;</code> | |
284 | <blockquote> | |
285 | <b>Returns:</b> <code>x.get()</code>. | |
286 | </blockquote> | |
287 | ||
288 | ||
289 | <h2> | |
290 | <a name="member_synopsis">Header | |
291 | <a href="../../../../boost/multi_index/member.hpp"> | |
292 | <code>"boost/multi_index/member.hpp"</code></a> synopsis</a></h2> | |
293 | ||
294 | <blockquote><pre> | |
295 | <span class=keyword>namespace</span> <span class=identifier>boost</span><span class=special>{</span> | |
296 | ||
297 | <span class=keyword>namespace</span> <span class=identifier>multi_index</span><span class=special>{</span> | |
298 | ||
299 | <span class=keyword>template</span><span class=special><</span><span class=keyword>class</span> <span class=identifier>Class</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Type</span><span class=special>,</span><span class=identifier>Type</span> <span class=identifier>Class</span><span class=special>::*</span><span class=identifier>PtrToMember</span><span class=special>></span> | |
300 | <span class=keyword>struct</span> <span class=identifier>member</span><span class=special>;</span> | |
301 | ||
302 | <span class=keyword>template</span><span class=special><</span><span class=keyword>class</span> <span class=identifier>Class</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Type</span><span class=special>,</span><span class=identifier>std</span><span class=special>::</span><span class=identifier>size_t</span> <span class=identifier>OffsetOfMember</span><span class=special>></span> | |
303 | <span class=keyword>struct</span> <span class=identifier>member_offset</span><span class=special>;</span> <span class=comment><b>// deprecated</b></span> | |
304 | ||
305 | <span class=preprocessor>#define</span> <span class=identifier>BOOST_MULTI_INDEX_MEMBER</span><span class=special>(</span><span class=identifier>Class</span><span class=special>,</span><span class=identifier>Type</span><span class=special>,</span><span class=identifier>MemberName</span><span class=special>)</span> <b>implementation defined</b> | |
306 | ||
307 | <span class=special>}</span> <span class=comment>// namespace boost::multi_index</span> | |
308 | ||
309 | <span class=special>}</span> <span class=comment>// namespace boost</span> | |
310 | </pre></blockquote> | |
311 | ||
312 | <h3><a name="member">Class template <code>member</code></a></h3> | |
313 | ||
314 | <p> | |
315 | <code>member</code> is a <a href="#key_extractors"><code>Key Extractor</code></a> | |
316 | aimed at accessing a given member of a class. | |
317 | </p> | |
318 | ||
319 | <blockquote><pre> | |
320 | <span class=keyword>template</span><span class=special><</span><span class=keyword>class</span> <span class=identifier>Class</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Type</span><span class=special>,</span><span class=identifier>Type</span> <span class=identifier>Class</span><span class=special>::*</span><span class=identifier>PtrToMember</span><span class=special>></span> | |
321 | <span class=keyword>struct</span> <span class=identifier>member</span> | |
322 | <span class=special>{</span> | |
323 | <span class=keyword>typedef</span> <span class=identifier>Type</span> <span class=identifier>result_type</span><span class=special>;</span> | |
324 | ||
325 | <span class=comment>// only provided if const ChainedPtr& is not convertible to const Class&</span> | |
326 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>ChainedPtr</span><span class=special>></span> <span class=identifier>Type</span><span class=special>&</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>ChainedPtr</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
327 | ||
328 | <span class=keyword>const</span> <span class=identifier>Type</span><span class=special>&</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>Class</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
329 | <span class=identifier>Type</span><span class=special>&</span> <span class=keyword>operator</span><span class=special>()(</span><span class=identifier>Class</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> <span class=comment>// only provided if Type is non-const</span> | |
330 | <span class=keyword>const</span> <span class=identifier>Type</span><span class=special>&</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span><span class=keyword>const</span> <span class=identifier>Class</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
331 | <span class=identifier>Type</span><span class=special>&</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span><span class=identifier>Class</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
332 | <span class=special>};</span> | |
333 | </pre></blockquote> | |
334 | ||
335 | <p> | |
336 | The <code>PtrToMember</code> template argument specifies the particular | |
337 | <code>Type Class::*</code> pointer to the member to be extracted. | |
338 | <code>member<Class,Type,PtrToMember></code> is a model of: | |
339 | <ul> | |
340 | <li>read/write <a href="#key_extractors"><code>Key Extractor</code></a> | |
341 | from <code>Class</code>,</li> | |
342 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
343 | from <code>reference_wrapper<const Class></code>,</li> | |
344 | <li>read/write <a href="#key_extractors"><code>Key Extractor</code></a> | |
345 | from <code>reference_wrapper<Class></code>,</li> | |
346 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
347 | from any <a href="#chained_pointers">chained pointer</a> | |
348 | to <code>const Class</code>,</li> | |
349 | <li>read/write <a href="#key_extractors"><code>Key Extractor</code></a> | |
350 | from any <a href="#chained_pointers">chained pointer</a> | |
351 | to <code>Class</code>.</li> | |
352 | </ul> | |
353 | </p> | |
354 | ||
355 | <h4><code>member</code> members</h4> | |
356 | ||
357 | <code>template<typename ChainedPtr> Type& operator()(const ChainedPtr& x)const;</code> | |
358 | ||
359 | <blockquote> | |
360 | <b>Requires:</b> <code>ChainedPtr</code> is a <a href="#chained_pointers">chained pointer</a> | |
361 | type to <code>Type</code>.<br> | |
362 | <b>Returns:</b> a reference to the object chained-pointed to by <code>x</code>. | |
363 | </blockquote> | |
364 | ||
365 | <code>const Type& operator()(const Class& x)const;</code> | |
366 | ||
367 | <blockquote> | |
368 | <b>Returns:</b> <code>x.*PtrToMember</code>. | |
369 | </blockquote> | |
370 | ||
371 | <code>Type& operator()(Class& x)const;</code> | |
372 | ||
373 | <blockquote> | |
374 | <b>Returns:</b> <code>x.*PtrToMember</code>. | |
375 | </blockquote> | |
376 | ||
377 | <code>const Type& operator()(const reference_wrapper<const Class>& x)const;</code> | |
378 | ||
379 | <blockquote> | |
380 | <b>Returns:</b> <code>x.get().*PtrToMember</code>. | |
381 | </blockquote> | |
382 | ||
383 | <code>Type& operator()(const reference_wrapper<Class>& x)const;</code> | |
384 | ||
385 | <blockquote> | |
386 | <b>Returns:</b> <code>x.get().*PtrToMember</code>. | |
387 | </blockquote> | |
388 | ||
389 | <h3><a name="member_offset">Class template <code>member_offset</code></a></h3> | |
390 | ||
391 | <p> | |
392 | <code>member_offset</code> was designed to overcome limitations of some legacy | |
393 | compilers and its use is currently deprecated. Refer to a | |
394 | <a href="http://www.boost.org/doc/libs/1_54_0/libs/multi_index/doc/reference/key_extraction.html#member_offset">former version</a> | |
395 | of Boost.MultiIndex for further information. | |
396 | </p> | |
397 | ||
398 | <h3><a name="boost_multi_index_member">Macro <code>BOOST_MULTI_INDEX_MEMBER</code></a></h3> | |
399 | ||
400 | <blockquote><pre> | |
401 | <span class=identifier>BOOST_MULTI_INDEX_MEMBER</span><span class=special>(</span><span class=identifier>Class</span><span class=special>,</span><span class=identifier>Type</span><span class=special>,</span><span class=identifier>MemberName</span><span class=special>)</span> | |
402 | </pre></blockquote> | |
403 | ||
404 | <p> | |
405 | This macro was designed as a portability mechanism for legacy compilers where <code>member</code> | |
406 | could not be supported. | |
407 | As such it is no longer needed in modern environments, though some users might still prefer it | |
408 | to plain <code>member</code> because it provides a slightly more concise syntax. | |
409 | </p> | |
410 | ||
411 | <h2> | |
412 | <a name="mem_fun_synopsis">Header | |
413 | <a href="../../../../boost/multi_index/mem_fun.hpp"> | |
414 | <code>"boost/multi_index/mem_fun.hpp"</code></a> synopsis</a></h2> | |
415 | ||
416 | <blockquote><pre> | |
417 | <span class=keyword>namespace</span> <span class=identifier>boost</span><span class=special>{</span> | |
418 | ||
419 | <span class=keyword>namespace</span> <span class=identifier>multi_index</span><span class=special>{</span> | |
420 | ||
421 | <span class=keyword>template</span><span class=special><</span><span class=keyword>class</span> <span class=identifier>Class</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Type</span><span class=special>,</span><span class=identifier>Type</span> <span class=special>(</span><span class=identifier>Class</span><span class=special>::*</span><span class=identifier>PtrToMemberFunction</span><span class=special>)()</span><span class=keyword>const</span><span class=special>></span> | |
422 | <span class=keyword>struct</span> <span class=identifier>const_mem_fun</span><span class=special>;</span> | |
423 | ||
424 | <span class=keyword>template</span><span class=special><</span><span class=keyword>class</span> <span class=identifier>Class</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Type</span><span class=special>,</span><span class=identifier>Type</span> <span class=special>(</span><span class=identifier>Class</span><span class=special>::*</span><span class=identifier>PtrToMemberFunction</span><span class=special>)()></span> | |
425 | <span class=keyword>struct</span> <span class=identifier>mem_fun</span><span class=special>;</span> | |
426 | ||
427 | <span class=keyword>template</span><span class=special><</span> | |
428 | <span class=keyword>class</span> <span class=identifier>Class</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Type</span><span class=special>,</span> | |
429 | <span class=keyword>typename</span> <span class=identifier>PtrToMemberFunctionType</span><span class=special>,</span><span class=identifier>PtrToMemberFunctionType</span> <span class=identifier>PtrToMemberFunction</span> | |
430 | <span class=special>></span> | |
431 | <span class=keyword>struct</span> <span class=identifier>const_mem_fun_explicit</span><span class=special>;</span> <span class=comment><b>// deprecated</b></span> | |
432 | ||
433 | <span class=keyword>template</span><span class=special><</span> | |
434 | <span class=keyword>class</span> <span class=identifier>Class</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Type</span><span class=special>,</span> | |
435 | <span class=keyword>typename</span> <span class=identifier>PtrToMemberFunctionType</span><span class=special>,</span><span class=identifier>PtrToMemberFunctionType</span> <span class=identifier>PtrToMemberFunction</span> | |
436 | <span class=special>></span> | |
437 | <span class=keyword>struct</span> <span class=identifier>mem_fun_explicit</span><span class=special>;</span> <span class=comment><b>// deprecated</b></span> | |
438 | ||
439 | <span class=preprocessor>#define</span> <span class=identifier>BOOST_MULTI_INDEX_CONST_MEM_FUN</span><span class=special>(</span><span class=identifier>Class</span><span class=special>,</span><span class=identifier>Type</span><span class=special>,</span><span class=identifier>MemberFunName</span><span class=special>)</span> <span class=special>\</span> | |
440 | <b>implementation defined</b> | |
441 | <span class=preprocessor>#define</span> <span class=identifier>BOOST_MULTI_INDEX_MEM_FUN</span><span class=special>(</span><span class=identifier>Class</span><span class=special>,</span><span class=identifier>Type</span><span class=special>,</span><span class=identifier>MemberFunName</span><span class=special>)</span> <span class=special>\</span> | |
442 | <b>implementation defined</b> | |
443 | ||
444 | <span class=special>}</span> <span class=comment>// namespace boost::multi_index</span> | |
445 | ||
446 | <span class=special>}</span> <span class=comment>// namespace boost</span> | |
447 | </pre></blockquote> | |
448 | ||
449 | <h3><a name="const_mem_fun">Class template <code>const_mem_fun</code></a></h3> | |
450 | ||
451 | <p> | |
452 | <code>const_mem_fun</code> is a <a href="#key_extractors"><code>Key Extractor</code></a> | |
453 | returning as key the result of invoking a given constant member function of a class. | |
454 | </p> | |
455 | ||
456 | <blockquote><pre> | |
457 | <span class=keyword>template</span><span class=special><</span><span class=keyword>class</span> <span class=identifier>Class</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Type</span><span class=special>,</span><span class=identifier>Type</span> <span class=special>(</span><span class=identifier>Class</span><span class=special>::*</span><span class=identifier>PtrToMemberFunction</span><span class=special>)()</span><span class=keyword>const</span><span class=special>></span> | |
458 | <span class=keyword>struct</span> <span class=identifier>const_mem_fun</span> | |
459 | <span class=special>{</span> | |
460 | <span class=keyword>typedef</span> <span class=keyword>typename</span> <span class=identifier>remove_reference</span><span class=special><</span><span class=identifier>Type</span><span class=special>>::</span><span class=identifier>type</span> <span class=identifier>result_type</span><span class=special>;</span> | |
461 | ||
462 | <span class=comment>// only provided if const ChainedPtr& is not convertible to const Class&</span> | |
463 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>ChainedPtr</span><span class=special>></span> <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>ChainedPtr</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
464 | ||
465 | <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>Class</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
466 | <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span><span class=keyword>const</span> <span class=identifier>Class</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
467 | <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span><span class=identifier>Class</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
468 | <span class=special>};</span> | |
469 | </pre></blockquote> | |
470 | ||
471 | <p> | |
472 | The <code>PtrToMemberFunction</code> template argument specifies the particular | |
473 | <code>Type (Class::*PtrToMemberFunction)()const</code> pointer to the constant | |
474 | member function used in the extraction. | |
475 | <code>const_mem_fun<Class,Type,PtrToMemberFunction></code> is a model of: | |
476 | <ul> | |
477 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
478 | from <code>Class</code>,</li> | |
479 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
480 | from <code>reference_wrapper<const Class></code>,</li> | |
481 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
482 | from <code>reference_wrapper<Class></code>,</li> | |
483 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
484 | from any <a href="#chained_pointers">chained pointer</a> | |
485 | to <code>const Class</code>,</li> | |
486 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
487 | from any <a href="#chained_pointers">chained pointer</a> | |
488 | to <code>Class</code>.</li> | |
489 | </ul> | |
490 | </p> | |
491 | ||
492 | <h4><code>const_mem_fun</code> members</h4> | |
493 | ||
494 | <code>template<typename ChainedPtr> Type operator()(const ChainedPtr& x)const;</code> | |
495 | ||
496 | <blockquote> | |
497 | <b>Requires:</b> <code>ChainedPtr</code> is a <a href="#chained_pointers">chained pointer</a> | |
498 | type to <code>Type</code>.<br> | |
499 | <b>Returns:</b> <code>(y.*PtrToMemberFunction)()</code>, where <code>y</code> is the | |
500 | object chained-pointed to by <code>x</code>. | |
501 | </blockquote> | |
502 | ||
503 | <code>Type operator()(const Class& x)const;</code> | |
504 | ||
505 | <blockquote> | |
506 | <b>Returns:</b> <code>(x.*PtrToMemberFunction)()</code>. | |
507 | </blockquote> | |
508 | ||
509 | <code>Type operator()(const reference_wrapper<const Class>& x)const;</code> | |
510 | ||
511 | <blockquote> | |
512 | <b>Returns:</b> <code>(x.get().*PtrToMemberFunction)()</code>. | |
513 | </blockquote> | |
514 | ||
515 | <code>Type operator()(const reference_wrapper<Class>& x)const;</code> | |
516 | ||
517 | <blockquote> | |
518 | <b>Returns:</b> <code>(x.get().*PtrToMemberFunction)()</code>. | |
519 | </blockquote> | |
520 | ||
521 | <h3><a name="mem_fun">Class template <code>mem_fun</code></a></h3> | |
522 | ||
523 | <p> | |
524 | <code>mem_fun</code> is a <a href="#key_extractors"><code>Key Extractor</code></a> | |
525 | returning as key the result of invoking a given member function of a class. | |
526 | </p> | |
527 | ||
528 | <blockquote><pre> | |
529 | <span class=keyword>template</span><span class=special><</span><span class=keyword>class</span> <span class=identifier>Class</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Type</span><span class=special>,</span><span class=identifier>Type</span> <span class=special>(</span><span class=identifier>Class</span><span class=special>::*</span><span class=identifier>PtrToMemberFunction</span><span class=special>)()></span> | |
530 | <span class=keyword>struct</span> <span class=identifier>mem_fun</span> | |
531 | <span class=special>{</span> | |
532 | <span class=keyword>typedef</span> <span class=keyword>typename</span> <span class=identifier>remove_reference</span><span class=special><</span><span class=identifier>Type</span><span class=special>>::</span><span class=identifier>type</span> <span class=identifier>result_type</span><span class=special>;</span> | |
533 | ||
534 | <span class=comment>// only provided if ChainedPtr& is not convertible to Class&</span> | |
535 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>ChainedPtr</span><span class=special>></span> <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>ChainedPtr</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
536 | ||
537 | <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=identifier>Class</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
538 | <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span><span class=identifier>Class</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
539 | <span class=special>};</span> | |
540 | </pre></blockquote> | |
541 | ||
542 | <p> | |
543 | The <code>PtrToMemberFunction</code> template argument specifies the particular | |
544 | <code>Type (Class::*PtrToMemberFunction)()</code> pointer to the member | |
545 | function used in the extraction. | |
546 | <code>mem_fun<Class,Type,PtrToMemberFunction></code> is a model of: | |
547 | <ul> | |
548 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
549 | from <code>reference_wrapper<Class></code>,</li> | |
550 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
551 | from any <a href="#chained_pointers">chained pointer</a> | |
552 | to <code>Class</code>.</li> | |
553 | </ul> | |
554 | </p> | |
555 | ||
556 | <h4><code>mem_fun</code> members</h4> | |
557 | ||
558 | <code>template<typename ChainedPtr> Type operator()(const ChainedPtr& x)const;</code> | |
559 | ||
560 | <blockquote> | |
561 | <b>Requires:</b> <code>ChainedPtr</code> is a <a href="#chained_pointers">chained pointer</a> | |
562 | type to <code>Type</code>.<br> | |
563 | <b>Returns:</b> <code>(y.*PtrToMemberFunction)()</code>, where <code>y</code> is the | |
564 | object chained-pointed to by <code>x</code>. | |
565 | </blockquote> | |
566 | ||
567 | <code>Type operator()(Class& x)const;</code> | |
568 | ||
569 | <blockquote> | |
570 | <b>Returns:</b> <code>(x.*PtrToMemberFunction)()</code>. | |
571 | </blockquote> | |
572 | ||
573 | <code>Type operator()(const reference_wrapper<Class>& x)const;</code> | |
574 | ||
575 | <blockquote> | |
576 | <b>Returns:</b> <code>(x.get().*PtrToMemberFunction)()</code>. | |
577 | </blockquote> | |
578 | ||
579 | <h3><a name="const_mem_fun_explicit">Class templates <code>const_mem_fun_explicit</code> and <code>mem_fun_explicit</code></a></h3> | |
580 | ||
581 | <p> | |
582 | These extractors were provided as a workaround for MSVC++ 6.0 and are now deprecated. | |
583 | Refer to a | |
584 | <a href="http://www.boost.org/doc/libs/1_54_0/libs/multi_index/doc/reference/key_extraction.html#const_mem_fun_explicit">former version</a> | |
585 | of Boost.MultiIndex for further information. | |
586 | </p> | |
587 | ||
588 | <h3><a name="boost_multi_index_const_mem_fun">Macros | |
589 | <code>BOOST_MULTI_INDEX_CONST_MEM_FUN</code> | |
590 | and <code>BOOST_MULTI_INDEX_MEM_FUN</code></a></h3> | |
591 | ||
592 | <blockquote><pre> | |
593 | <span class=identifier>BOOST_MULTI_INDEX_CONST_MEM_FUN</span><span class=special>(</span><span class=identifier>Class</span><span class=special>,</span><span class=identifier>Type</span><span class=special>,</span><span class=identifier>MemberFunName</span><span class=special>)</span> | |
594 | <span class=identifier>BOOST_MULTI_INDEX_MEM_FUN</span><span class=special>(</span><span class=identifier>Class</span><span class=special>,</span><span class=identifier>Type</span><span class=special>,</span><span class=identifier>MemberFunName</span><span class=special>)</span> | |
595 | </pre></blockquote> | |
596 | ||
597 | <p> | |
598 | Portability macros for usage of <code>const_mem_fun</code> and <code>mem_fun</code>. | |
599 | Although no longer needed in modern compilers, some users might still decide to | |
600 | resort to them as they provide a slightly more concise syntax. | |
601 | </p> | |
602 | ||
603 | <h2> | |
604 | <a name="global_fun_synopsis">Header | |
605 | <a href="../../../../boost/multi_index/global_fun.hpp"> | |
606 | <code>"boost/multi_index/global_fun.hpp"</code></a> synopsis</a></h2> | |
607 | ||
608 | <blockquote><pre> | |
609 | <span class=keyword>namespace</span> <span class=identifier>boost</span><span class=special>{</span> | |
610 | ||
611 | <span class=keyword>namespace</span> <span class=identifier>multi_index</span><span class=special>{</span> | |
612 | ||
613 | <span class=keyword>template</span><span class=special><</span><span class=keyword>class</span> <span class=identifier>Value</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Type</span><span class=special>,</span><span class=identifier>Type</span> <span class=special>(*</span><span class=identifier>PtrToFunction</span><span class=special>)(</span><span class=identifier>Value</span><span class=special>)></span> | |
614 | <span class=keyword>struct</span> <span class=identifier>global_fun</span><span class=special>;</span> | |
615 | ||
616 | <span class=special>}</span> <span class=comment>// namespace boost::multi_index</span> | |
617 | ||
618 | <span class=special>}</span> <span class=comment>// namespace boost</span> | |
619 | </pre></blockquote> | |
620 | ||
621 | <h3><a name="global_fun">Class template <code>global_fun</code></a></h3> | |
622 | ||
623 | <p> | |
624 | <code>global_fun</code> is a <a href="#key_extractors"><code>Key Extractor</code></a> | |
625 | based on a given global or static member function accepting the base type as argument | |
626 | and returning the associated key. | |
627 | </p> | |
628 | ||
629 | <blockquote><pre> | |
630 | <span class=keyword>template</span><span class=special><</span><span class=keyword>class</span> <span class=identifier>Value</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Type</span><span class=special>,</span><span class=identifier>Type</span> <span class=special>(*</span><span class=identifier>PtrToFunction</span><span class=special>)(</span><span class=identifier>Value</span><span class=special>)></span> | |
631 | <span class=keyword>struct</span> <span class=identifier>global_fun</span> | |
632 | <span class=special>{</span> | |
633 | <span class=keyword>typedef</span> <span class=keyword>typename</span> <span class=identifier>remove_reference</span><span class=special><</span><span class=identifier>Type</span><span class=special>>::</span><span class=identifier>type</span> <span class=identifier>result_type</span><span class=special>;</span> | |
634 | ||
635 | <span class=comment>// Only provided under the following circumstances: | |
636 | // - If Value is a reference to a constant type, only provided | |
637 | // when const ChainedPtr& is not convertible to Value; | |
638 | // - if Value is a reference to a non-const type, only provided | |
639 | // when ChainedPtr& is not convertible to Value; | |
640 | // - else, only provided when const ChainedPtr& is not | |
641 | // convertible to const Value&.</span> | |
642 | <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>ChainedPtr</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
643 | ||
644 | <span class=comment>// only provided if Value is a reference type</span> | |
645 | <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=identifier>Value</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
646 | ||
647 | <span class=comment>// only provided if Value is not a reference type</span> | |
648 | <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>Value</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
649 | ||
650 | <span class=comment>// only provided if Value is not a reference type</span> | |
651 | <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span><span class=keyword>const</span> <span class=identifier>Value</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
652 | ||
653 | <span class=comment>// only provided if Value is a reference type</span> | |
654 | <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span> | |
655 | <span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span> | |
656 | <span class=identifier>remove_reference</span><span class=special><</span><span class=identifier>Value</span><span class=special>>::</span><span class=identifier>type</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
657 | ||
658 | <span class=comment>// only provided if Value is not a reference type or is | |
659 | // a reference to a constant type</span> | |
660 | <span class=identifier>Type</span> <span class=keyword>operator</span><span class=special>()(</span> | |
661 | <span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span> | |
662 | <span class=keyword>typename</span> <span class=identifier>remove_const</span><span class=special><</span> | |
663 | <span class=keyword>typename</span> <span class=identifier>remove_reference</span><span class=special><</span><span class=identifier>Value</span><span class=special>>::</span><span class=identifier>type</span><span class=special>>::</span><span class=identifier>type</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
664 | <span class=special>};</span> | |
665 | </pre></blockquote> | |
666 | ||
667 | <p> | |
668 | <code>PtrToFunction</code> specifies the particular function used to extract | |
669 | the key of type <code>Type</code> from some <code>BaseType</code>. | |
670 | <code>global_fun</code> supports the following function signatures: | |
671 | <ul> | |
672 | <li><code>Type f(BaseType)</code> (<code>Value</code> is <code>BaseType</code>),</li> | |
673 | <li><code>Type f(const BaseType&)</code> (<code>Value</code> is <code>const BaseType&</code>),</li> | |
674 | <li><code>Type f(BaseType&)</code> (<code>Value</code> is <code>BaseType&</code>).</li> | |
675 | </ul> | |
676 | <code>global_fun<Type,Value,PtrToFunction></code> is a model of: | |
677 | <ul> | |
678 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
679 | from <code>reference_wrapper<BaseType></code>,</li> | |
680 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
681 | from any <a href="#chained_pointers">chained pointer</a> | |
682 | to <code>BaseType</code>.</li> | |
683 | </ul> | |
684 | When <code>Value</code> is <code>BaseType</code> or | |
685 | <code>const BaseType&</code>, | |
686 | <code>global_fun<Type,Value,PtrToFunction></code> is also a model of: | |
687 | <ul> | |
688 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
689 | from <code>BaseType</code>,</li> | |
690 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
691 | from <code>reference_wrapper<const BaseType></code>,</li> | |
692 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
693 | from any <a href="#chained_pointers">chained pointer</a> | |
694 | to <code>const BaseType</code>.</li> | |
695 | </ul> | |
696 | </p> | |
697 | ||
698 | <h4><code>global_fun</code> members</h4> | |
699 | ||
700 | <code>template<typename ChainedPtr> Type operator()(const ChainedPtr& x)const;</code> | |
701 | ||
702 | <blockquote> | |
703 | <b>Requires:</b> <code>ChainedPtr</code> is a <a href="#chained_pointers">chained pointer</a> | |
704 | type to <code>Value</code>.<br> | |
705 | <b>Returns:</b> <code>PtrToFunction)(y)</code>, where <code>y</code> is the | |
706 | object chained-pointed to by <code>x</code>. | |
707 | </blockquote> | |
708 | ||
709 | <code>Type operator()(Value x)const;</code> | |
710 | ||
711 | <blockquote> | |
712 | <b>Returns:</b> <code>PtrToFunction(x)</code>. | |
713 | </blockquote> | |
714 | ||
715 | <code>Type operator()(const Value& x)const;</code> | |
716 | ||
717 | <blockquote> | |
718 | <b>Returns:</b> <code>PtrToFunction(x)</code>. | |
719 | </blockquote> | |
720 | ||
721 | <code>Type operator()(const reference_wrapper<const Value>& x)const;</code> | |
722 | ||
723 | <blockquote> | |
724 | <b>Returns:</b> <code>PtrToFunction(x.get())</code>. | |
725 | </blockquote> | |
726 | ||
727 | <code> | |
728 | Type operator()(<br> | |
729 | const reference_wrapper<remove_reference<Value>::type>& x)const;</code> | |
730 | ||
731 | <blockquote> | |
732 | <b>Returns:</b> <code>PtrToFunction(x.get())</code>. | |
733 | </blockquote> | |
734 | ||
735 | <code>Type operator()(<br> | |
736 | const reference_wrapper<<br> | |
737 | typename remove_const<<br> | |
738 | typename remove_reference<Value>::type>::type>& x)const;</code> | |
739 | ||
740 | <blockquote> | |
741 | <b>Returns:</b> <code>PtrToFunction(x.get())</code>. | |
742 | </blockquote> | |
743 | ||
744 | <h2> | |
745 | <a name="composite_key_synopsis">Header | |
746 | <a href="../../../../boost/multi_index/composite_key.hpp"> | |
747 | <code>"boost/multi_index/composite_key.hpp"</code></a> synopsis</a></h2> | |
748 | ||
749 | <blockquote><pre> | |
750 | <span class=keyword>namespace</span> <span class=identifier>boost</span><span class=special>{</span> | |
751 | ||
752 | <span class=keyword>namespace</span> <span class=identifier>multi_index</span><span class=special>{</span> | |
753 | ||
754 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>KeyFromValue0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>KeyFromValuen</span><span class=special>></span> | |
755 | <span class=keyword>struct</span> <span class=identifier>composite_key</span><span class=special>;</span> | |
756 | ||
757 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
758 | <span class=keyword>struct</span> <span class=identifier>composite_key_result</span><span class=special>;</span> | |
759 | ||
760 | <span class=comment>// comparison operators for composite_key_result:</span> | |
761 | ||
762 | <span class=comment>// <b>OP</b> is any of ==,<,!=,>,>=,<=</span> | |
763 | ||
764 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey1</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey2</span><span class=special>></span> | |
765 | <span class=keyword>bool</span> <span class=keyword>operator</span> <b><i>OP</i></b><span class=special>(</span> | |
766 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey1</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
767 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey2</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>);</span> | |
768 | ||
769 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
770 | <span class=keyword>bool</span> <span class=keyword>operator</span> <b><i>OP</i></b><span class=special>(</span> | |
771 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
772 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>y</span><span class=special>);</span> | |
773 | ||
774 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
775 | <span class=keyword>bool</span> <span class=keyword>operator</span> <b><i>OP</i></b><span class=special>(</span> | |
776 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>x</span><span class=special>,</span> | |
777 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>);</span> | |
778 | ||
779 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>></span> | |
780 | <span class=keyword>bool</span> <span class=keyword>operator</span> <b><i>OP</i></b><span class=special>(</span> | |
781 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
782 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>);</span> | |
783 | ||
784 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
785 | <span class=keyword>bool</span> <span class=keyword>operator</span> <b><i>OP</i></b><span class=special>(</span> | |
786 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
787 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>);</span> | |
788 | ||
789 | <span class=comment>// equality functors:</span> | |
790 | ||
791 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Pred0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Predn</span><span class=special>></span> | |
792 | <span class=keyword>struct</span> <span class=identifier>composite_key_equal_to</span><span class=special>;</span> | |
793 | ||
794 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKeyResult</span><span class=special>></span> | |
795 | <span class=keyword>struct</span> <span class=identifier>composite_key_result_equal_to</span><span class=special>;</span> <span class=comment><b>// deprecated</b></span> | |
796 | ||
797 | <span class=comment>// comparison functors:</span> | |
798 | ||
799 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Compare0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Comparen</span><span class=special>></span> | |
800 | <span class=keyword>struct</span> <span class=identifier>composite_key_compare</span><span class=special>;</span> | |
801 | ||
802 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKeyResult</span><span class=special>></span> | |
803 | <span class=keyword>struct</span> <span class=identifier>composite_key_result_less</span><span class=special>;</span> <span class=comment><b>// deprecated</b></span> | |
804 | ||
805 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKeyResult</span><span class=special>></span> | |
806 | <span class=keyword>struct</span> <span class=identifier>composite_key_result_greater</span><span class=special>;</span> <span class=comment><b>// deprecated</b></span> | |
807 | ||
808 | <span class=comment>// hash functors:</span> | |
809 | ||
810 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Hash0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Hashn</span><span class=special>></span> | |
811 | <span class=keyword>struct</span> <span class=identifier>composite_key_hash</span><span class=special>;</span> | |
812 | ||
813 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKeyResult</span><span class=special>></span> | |
814 | <span class=keyword>struct</span> <span class=identifier>composite_key_result_hash</span><span class=special>;</span> <span class=comment><b>// deprecated</b></span> | |
815 | ||
816 | <span class=special>}</span> <span class=comment>// namespace boost::multi_index</span> | |
817 | ||
818 | <span class=special>}</span> <span class=comment>// namespace boost</span> | |
819 | ||
820 | <span class=comment>// specializations of external functors for composite_key_result:</span> | |
821 | ||
822 | <span class=keyword>namespace</span> <span class=identifier>std</span><span class=special>{</span> | |
823 | ||
824 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
825 | <span class=keyword>struct</span> <span class=identifier>equal_to</span><span class=special><</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>></span> <span class=special>>;</span> | |
826 | ||
827 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
828 | <span class=keyword>struct</span> <span class=identifier>less</span><span class=special><</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>></span> <span class=special>>;</span> | |
829 | ||
830 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
831 | <span class=keyword>struct</span> <span class=identifier>greater</span><span class=special><</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>></span> <span class=special>>;</span> | |
832 | ||
833 | <span class=special>}</span> <span class=comment>// namespace std</span> | |
834 | ||
835 | <span class=keyword>namespace</span> <span class=identifier>boost</span><span class=special>{</span> | |
836 | ||
837 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
838 | <span class=keyword>struct</span> <span class=identifier>hash</span><span class=special><</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>></span> <span class=special>>;</span> | |
839 | ||
840 | <span class=special>}</span> <span class=comment>// namespace boost</span> | |
841 | </pre></blockquote> | |
842 | ||
843 | <h3><a name="composite_key">Class template <code>composite_key</code></a></h3> | |
844 | ||
845 | <p> | |
846 | <code>composite_key</code> is a <a href="#key_extractors"><code>Key Extractor</code></a> | |
847 | returning the combined value of several key extractors whose type is specified | |
848 | at compile time. The returned object is of type | |
849 | <a href="#composite_key_result"> | |
850 | <code>composite_key_result</code></a><code><composite_key></code>. | |
851 | </p> | |
852 | ||
853 | <blockquote><pre> | |
854 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>KeyFromValue0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>KeyFromValuen</span><span class=special>></span> | |
855 | <span class=keyword>struct</span> <span class=identifier>composite_key</span> | |
856 | <span class=special>{</span> | |
857 | <span class=keyword>typedef</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>KeyFromValue0</span><span class=special>,...,</span><span class=identifier>KeyFromValuen</span><span class=special>></span> <span class=identifier>key_extractor_tuple</span><span class=special>;</span> | |
858 | <span class=keyword>typedef</span> <span class=identifier>Value</span> <span class=identifier>value_type</span><span class=special>;</span> | |
859 | <span class=keyword>typedef</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>composite_key</span><span class=special>></span> <span class=identifier>result_type</span><span class=special>;</span> | |
860 | ||
861 | <span class=identifier>composite_key</span><span class=special>(</span> | |
862 | <span class=keyword>const</span> <span class=identifier>KeyFromValue0</span><span class=special>&</span> <span class=identifier>k0</span><span class=special>=</span><span class=identifier>KeyFromValue0</span><span class=special>(),</span> | |
863 | <span class=special>...</span> | |
864 | <span class=keyword>const</span> <span class=identifier>KeyFromValuen</span><span class=special>&</span> <span class=identifier>kn</span><span class=special>=</span><span class=identifier>KeyFromValuen</span><span class=special>());</span> | |
865 | ||
866 | <span class=identifier>composite_key</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>key_extractor_tuple</span><span class=special>&</span> <span class=identifier>x</span><span class=special>);</span> | |
867 | ||
868 | <span class=keyword>const</span> <span class=identifier>key_extractor_tuple</span><span class=special>&</span> <span class=identifier>key_extractors</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span> | |
869 | <span class=identifier>key_extractor_tuple</span><span class=special>&</span> <span class=identifier>key_extractors</span><span class=special>()</span> | |
870 | ||
871 | <span class=comment>// only provided if const ChainedPtr& is not convertible to const value_type&</span> | |
872 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>ChainedPtr</span><span class=special>></span> | |
873 | <span class=identifier>result_type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>ChainedPtr</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
874 | ||
875 | <span class=identifier>result_type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>value_type</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
876 | <span class=identifier>result_type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span><span class=keyword>const</span> <span class=identifier>value_type</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
877 | <span class=identifier>result_type</span> <span class=keyword>operator</span><span class=special>()(</span><span class=keyword>const</span> <span class=identifier>reference_wrapper</span><span class=special><</span><span class=identifier>value_type</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
878 | <span class=special>};</span> | |
879 | </pre></blockquote> | |
880 | ||
881 | <p> | |
882 | <code>KeyFromValue0</code>, ... , <code>KeyFromValuen</code> are the types of | |
883 | the key extractors combined into the composite key. Each of these types | |
884 | must be a <a href="#key_extractors"><code>Key Extractor</code></a> from | |
885 | <code>Value</code>. At least a key extractor must be provided. The maximum | |
886 | number of key extractors of a <code>composite_key</code> instantiation is | |
887 | implementation defined. <code>composite_key</code> internally stores an | |
888 | object of every constituent key extractor type. | |
889 | <code>composite_key<Value,KeyFromValue0,...,KeyFromValuen></code> is a model | |
890 | of: | |
891 | <ul> | |
892 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
893 | from <code>Value</code>,</li> | |
894 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
895 | from <code>reference_wrapper<const Value></code>,</li> | |
896 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
897 | from <code>reference_wrapper<Value></code>,</li> | |
898 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
899 | from any <a href="#chained_pointers">chained pointer</a> | |
900 | to <code>const Value</code>,</li> | |
901 | <li><a href="#key_extractors"><code>Key Extractor</code></a> | |
902 | from any <a href="#chained_pointers">chained pointer</a> | |
903 | to <code>Value</code>.</li> | |
904 | </ul> | |
905 | </p> | |
906 | ||
907 | <h4><code>composite_key</code> members</h4> | |
908 | ||
909 | <code>composite_key(<br> | |
910 | const KeyFromValue0& k0=KeyFromValue0(),<br> | |
911 | ...<br> | |
912 | const KeyFromValuen& kn=KeyFromValuen()); | |
913 | </code> | |
914 | ||
915 | <blockquote> | |
916 | <b>Effects:</b> Constructs a <code>composite_key</code> that stores | |
917 | copies of the key extractor objects supplied. | |
918 | </blockquote> | |
919 | ||
920 | <code>composite_key(const key_extractor_tuple& x);</code> | |
921 | ||
922 | <blockquote> | |
923 | <b>Effects:</b> Constructs a <code>composite_key</code> that stores | |
924 | copies of the key extractor objects supplied in <code>x</code>. | |
925 | </blockquote> | |
926 | ||
927 | <code>const key_extractor_tuple& key_extractors()const;</code> | |
928 | ||
929 | <blockquote> | |
930 | <b>Returns:</b> a constant reference to a tuple holding the | |
931 | key extractors internally stored by the <code>composite_key</code>. | |
932 | </blockquote> | |
933 | ||
934 | <code>key_extractor_tuple& key_extractors();</code> | |
935 | ||
936 | <blockquote> | |
937 | <b>Returns:</b> a reference to a tuple holding the | |
938 | key extractors internally stored by the <code>composite_key</code>. | |
939 | </blockquote> | |
940 | ||
941 | <code>template<typename ChainedPtr><br> | |
942 | result_type operator()(const ChainedPtr& x)const;</code> | |
943 | ||
944 | <blockquote> | |
945 | <b>Requires:</b> <code>ChainedPtr</code> is a <a href="#chained_pointers">chained pointer</a> | |
946 | type to <code>result_type</code>.<br> | |
947 | <b>Returns:</b> a <code>result_type</code> object dependent on | |
948 | <code>*this</code> and <code>y</code>, where <code>y</code> is the | |
949 | object chained-pointed to by <code>x</code>. | |
950 | </blockquote> | |
951 | ||
952 | <code>result_type operator()(const value_type& x)const;</code> | |
953 | ||
954 | <blockquote> | |
955 | <b>Returns:</b> a <code>result_type</code> object dependent on | |
956 | <code>*this</code> and <code>x</code>. | |
957 | </blockquote> | |
958 | ||
959 | <code>result_type operator()(const reference_wrapper<const value_type>& x)const;</code> | |
960 | ||
961 | <blockquote> | |
962 | <b>Returns:</b> a <code>result_type</code> object dependent on | |
963 | <code>*this</code> and <code>x.get()</code>. | |
964 | </blockquote> | |
965 | ||
966 | <code>result_type operator()(const reference_wrapper<value_type>& x)const;</code> | |
967 | ||
968 | <blockquote> | |
969 | <b>Returns:</b> a <code>result_type</code> object dependent on | |
970 | <code>*this</code> and <code>x.get()</code>. | |
971 | </blockquote> | |
972 | ||
973 | <h3><a name="composite_key_result">Class template | |
974 | <code>composite_key_result</code></a></h3> | |
975 | ||
976 | <p> | |
977 | This is an opaque type returned by <code>composite_key</code> | |
978 | instantiations as their extracted key. | |
979 | </p> | |
980 | ||
981 | <blockquote><pre> | |
982 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
983 | <span class=keyword>struct</span> <span class=identifier>composite_key_result</span> | |
984 | <span class=special>{</span> | |
985 | <b>no public interface available</b> | |
986 | <span class=special>};</span> | |
987 | ||
988 | <span class=comment>// comparison:</span> | |
989 | ||
990 | <span class=comment>// <b>OP</b> is any of ==,<,!=,>,>=,<=</span> | |
991 | ||
992 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey1</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey2</span><span class=special>></span> | |
993 | <span class=keyword>bool</span> <span class=keyword>operator</span> <b><i>OP</i></b><span class=special>(</span> | |
994 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey1</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
995 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey2</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>);</span> | |
996 | ||
997 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
998 | <span class=keyword>bool</span> <span class=keyword>operator</span> <b><i>OP</i></b><span class=special>(</span> | |
999 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1000 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>y</span><span class=special>);</span> | |
1001 | ||
1002 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1003 | <span class=keyword>bool</span> <span class=keyword>operator</span> <b><i>OP</i></b><span class=special>(</span> | |
1004 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1005 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>);</span> | |
1006 | ||
1007 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>></span> | |
1008 | <span class=keyword>bool</span> <span class=keyword>operator</span> <b><i>OP</i></b><span class=special>(</span> | |
1009 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1010 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>);</span> | |
1011 | ||
1012 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1013 | <span class=keyword>bool</span> <span class=keyword>operator</span> <b><i>OP</i></b><span class=special>(</span> | |
1014 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1015 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>);</span> | |
1016 | </pre></blockquote> | |
1017 | ||
1018 | <code>CompositeKey</code> is the <code>composite_key</code> instantiation to | |
1019 | which the <code>composite_key_result</code> type is associated. Objects of type | |
1020 | <code>composite_key_result</code> returned by a composite key must be always treated | |
1021 | as <i>temporary</i>, i.e. they should not be stored or copied. | |
1022 | <code>composite_key_result</code> is <i>not</i> guaranteed to be | |
1023 | <code>DefaultConstructible</code> or <code>CopyAssignable</code>. | |
1024 | Every object of type <code>composite_key_result<CompositeKey></code> is | |
1025 | internally associated to the <code>CompositeKey</code> from which it is returned | |
1026 | and the object of type <code>CompositeKey::value_type</code> to which the | |
1027 | composite key was applied. | |
1028 | </p> | |
1029 | ||
1030 | <h4><a name="ckey_result_notation">Notation</a></h4> | |
1031 | ||
1032 | <p> | |
1033 | Given an <code>x</code> of type <code>composite_key_result<CompositeKey></code>, | |
1034 | we use the following notation: | |
1035 | <ul> | |
1036 | <li><code>ck(x)</code> is the <code>CompositeKey</code> object associated to | |
1037 | <code>x</code>,</li> | |
1038 | <li><code>v(x)</code> is the object of type <code>CompositeKey::value_type</code> | |
1039 | associated to <code>x</code>,</li> | |
1040 | <li><code>k<sub>i</sub>(x) = ck(x).key_extractors().get<i>()</code>, | |
1041 | that is, is the <code>i</code>-th key extractor of <code>ck(x)</code>,</li> | |
1042 | <li><code>x<sub>i</sub> = k<sub>i</sub>(x)(v(x))</code>, that is, the | |
1043 | key extracted from <code>v(x)</code> by the <code>i</code>-th key extractor,</li> | |
1044 | <li><code>length(x)</code> is the number of key extractors of <code>ck(x)</code>.</li> | |
1045 | </ul> | |
1046 | Also, if <code>y</code> is an <code>std::tuple</code> or <code>boost::tuple</code> of values, we define: | |
1047 | <ul> | |
1048 | <li><code>y<sub>i</sub>=get<i>(y)</code>,</li> | |
1049 | <li><code>length(y)</code> is the number of elements of <code>y</code>.</li> | |
1050 | </ul> | |
1051 | </p> | |
1052 | ||
1053 | <h4>Comparison operators</h4> | |
1054 | ||
1055 | <code>template<typename CompositeKey1,typename CompositeKey2><br> | |
1056 | bool operator==(<br> | |
1057 | const composite_key_result<CompositeKey1>& x,<br> | |
1058 | const composite_key_result<CompositeKey2>& y);<br> | |
1059 | template<typename CompositeKey,typename... Values><br> | |
1060 | bool operator==(<br> | |
1061 | const composite_key_result<CompositeKey>& x,<br> | |
1062 | const std::tuple<Values...>& y);<br> | |
1063 | template<typename CompositeKey,typename... Values><br> | |
1064 | bool operator==(<br> | |
1065 | const std::tuple<Values...>& x,<br> | |
1066 | const composite_key_result<CompositeKey>& y);<br> | |
1067 | template<typename CompositeKey,typename Value0,...,typename Valuen><br> | |
1068 | bool operator==(<br> | |
1069 | const composite_key_result<CompositeKey>& x,<br> | |
1070 | const boost::tuple<Value0,...,Valuen>& y);<br> | |
1071 | template<typename Value0,...,typename Valuen,typename CompositeKey><br> | |
1072 | bool operator==(<br> | |
1073 | const boost::tuple<Value0,...,Valuen>& x,<br> | |
1074 | const composite_key_result<CompositeKey>& y); | |
1075 | </code> | |
1076 | ||
1077 | <blockquote> | |
1078 | <b>Requires:</b> <code>length(x)==length(y)</code>. The expression | |
1079 | <code>x<sub>i</sub>==y<sub>i</sub></code> is valid for all <code>i</code> | |
1080 | in <code>[0,length(x))</code>.<br> | |
1081 | <b>Returns:</b> <code>true</code> if and only if | |
1082 | <blockquote> | |
1083 | <code>x<sub>i</sub>==y<sub>i</sub></code> for all <code>i</code> | |
1084 | in <code>[0,length(x))</code>. | |
1085 | </blockquote> | |
1086 | <b>Complexity:</b> No more key extraction operations and comparisons | |
1087 | are performed than those necessary for the evaluation of the expression above, | |
1088 | starting at <code>i==0</code>. The evaluation is short-circuited as soon as | |
1089 | the result is determined to be <code>false</code>. | |
1090 | </blockquote> | |
1091 | ||
1092 | <code>template<typename CompositeKey1,typename CompositeKey2><br> | |
1093 | bool operator<(<br> | |
1094 | const composite_key_result<CompositeKey1>& x,<br> | |
1095 | const composite_key_result<CompositeKey2>& y);<br> | |
1096 | template<typename CompositeKey,typename... Values><br> | |
1097 | bool operator<(<br> | |
1098 | const composite_key_result<CompositeKey>& x,<br> | |
1099 | const std::tuple<Values...>& y);<br> | |
1100 | template<typename CompositeKey,typename... Values><br> | |
1101 | bool operator<(<br> | |
1102 | const std::tuple<Values...>& x,<br> | |
1103 | const composite_key_result<CompositeKey>& y);<br> | |
1104 | template<typename CompositeKey,typename Value0,...,typename Valuen><br> | |
1105 | bool operator<(<br> | |
1106 | const composite_key_result<CompositeKey>& x,<br> | |
1107 | const boost::tuple<Value0,...,Valuen>& y);<br> | |
1108 | template<typename Value0,...,typename Valuen,typename CompositeKey><br> | |
1109 | bool operator<(<br> | |
1110 | const boost::tuple<Value0,...,Valuen>& x,<br> | |
1111 | const composite_key_result<CompositeKey>& y); | |
1112 | </code> | |
1113 | ||
1114 | <blockquote> | |
1115 | <b>Requires:</b> The expressions | |
1116 | <code>x<sub>i</sub><y<sub>i</sub></code> and | |
1117 | <code>y<sub>i</sub><x<sub>i</sub></code> are valid for all <code>i</code> | |
1118 | in <code>[0,min(length(x),length(y)))</code>.<br> | |
1119 | <b>Returns:</b> <code>true</code> if and only if there exists some | |
1120 | <code>j</code> in the range <code>[0,min(length(x),length(y)))</code> | |
1121 | such that | |
1122 | <blockquote> | |
1123 | <code>!(x<sub>i</sub><y<sub>i</sub>) && !(y<sub>i</sub><x<sub>i</sub>)</code> | |
1124 | for all <code>i</code> in <code>[0,j)</code>,<br> | |
1125 | <code> x<sub>j</sub><y<sub>j</sub></code>. | |
1126 | </blockquote> | |
1127 | <b>Complexity:</b> No more key extraction operations and comparisons | |
1128 | are performed than those necessary for the evaluation of the expression above, | |
1129 | starting at <code>i==0</code>. The evaluation is short-circuited as soon as | |
1130 | the result is determined to be <code>false</code>. | |
1131 | </blockquote> | |
1132 | ||
1133 | <code>template<typename CompositeKey1,typename CompositeKey2><br> | |
1134 | bool operator <b><i>OP</i></b>(<br> | |
1135 | const composite_key_result<CompositeKey1>& x,<br> | |
1136 | const composite_key_result<CompositeKey2>& y);<br> | |
1137 | template<typename CompositeKey,typename... Values><br> | |
1138 | bool operator <b><i>OP</i></b>(<br> | |
1139 | const composite_key_result<CompositeKey>& x,<br> | |
1140 | const std::tuple<Values...>& y);<br> | |
1141 | template<typename CompositeKey,typename... Values><br> | |
1142 | bool operator <b><i>OP</i></b>(<br> | |
1143 | const std::tuple<Values...>& x,<br> | |
1144 | const composite_key_result<CompositeKey>& y);<br> | |
1145 | template<typename CompositeKey,typename Value0,...,typename Valuen><br> | |
1146 | bool operator <b><i>OP</i></b>(<br> | |
1147 | const composite_key_result<CompositeKey>& x,<br> | |
1148 | const boost::tuple<Value0,...,Valuen>& y);<br> | |
1149 | template<typename Value0,...,typename Valuen,typename CompositeKey><br> | |
1150 | bool operator <b><i>OP</i></b>(<br> | |
1151 | const boost::tuple<Value0,...,Valuen>& x,<br> | |
1152 | const composite_key_result<CompositeKey>& y); | |
1153 | </code> | |
1154 | ||
1155 | <p> | |
1156 | (<code><b><i>OP</i></b></code> is any of <code>!=</code>, <code>></code>, | |
1157 | <code>>=</code>, <code><=</code>.) | |
1158 | </p> | |
1159 | ||
1160 | <blockquote> | |
1161 | <b>Requires:</b> The expressions given below are valid (for the particular | |
1162 | <code><b><i>OP</i></b></code> considered.)<br> | |
1163 | <b>Returns:</b> <code>true</code> if and only if | |
1164 | <blockquote> | |
1165 | <code>!(x==y)</code> (<code><b><i>OP</i></b></code> is <code>!=</code>),<br> | |
1166 | <code> y< x </code> (<code><b><i>OP</i></b></code> is <code>> </code>),<br> | |
1167 | <code>!(x< y)</code> (<code><b><i>OP</i></b></code> is <code>>=</code>),<br> | |
1168 | <code>!(y< x)</code> (<code><b><i>OP</i></b></code> is <code><=</code>). | |
1169 | </blockquote> | |
1170 | </blockquote> | |
1171 | ||
1172 | <h3><a name="ckey_result_equality">Equality</a></h3> | |
1173 | ||
1174 | <h4><a name="composite_key_equal_to">Class template | |
1175 | <code>composite_key_equal_to</code></a></h4> | |
1176 | ||
1177 | <p> | |
1178 | <code>composite_key_equal_to</code> tests for equality between | |
1179 | <code>composite_key_result</code> instantiations and between | |
1180 | these and tuples of values, using an internally stored | |
1181 | collection of elementary equality predicates. | |
1182 | </p> | |
1183 | ||
1184 | <blockquote><pre> | |
1185 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Pred0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Predn</span><span class=special>></span> | |
1186 | <span class=keyword>struct</span> <span class=identifier>composite_key_equal_to</span> | |
1187 | <span class=special>{</span> | |
1188 | <span class=keyword>typedef</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Pred0</span><span class=special>,...,</span><span class=identifier>Predn</span><span class=special>></span> <span class=identifier>key_eq_tuple</span><span class=special>;</span> | |
1189 | ||
1190 | <span class=identifier>composite_key_equal_to</span><span class=special>(</span> | |
1191 | <span class=keyword>const</span> <span class=identifier>Pred0</span><span class=special>&</span> <span class=identifier>p0</span><span class=special>=</span><span class=identifier>Pred0</span><span class=special>(),</span> | |
1192 | <span class=special>...</span> | |
1193 | <span class=keyword>const</span> <span class=identifier>Predn</span><span class=special>&</span> <span class=identifier>pn</span><span class=special>=</span><span class=identifier>Predn</span><span class=special>());</span> | |
1194 | ||
1195 | <span class=identifier>composite_key_equal_to</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>key_eq_tuple</span><span class=special>&</span> <span class=identifier>x</span><span class=special>);</span> | |
1196 | ||
1197 | <span class=keyword>const</span> <span class=identifier>key_eq_tuple</span><span class=special>&</span> <span class=identifier>key_eqs</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span> | |
1198 | <span class=identifier>key_eq_tuple</span><span class=special>&</span> <span class=identifier>key_eqs</span><span class=special>()</span><span class=special>;</span> | |
1199 | ||
1200 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey1</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey2</span><span class=special>></span> | |
1201 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1202 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey1</span><span class=special>></span> <span class=special>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1203 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey2</span><span class=special>></span> <span class=special>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1204 | ||
1205 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1206 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1207 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1208 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1209 | ||
1210 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1211 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1212 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1213 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1214 | ||
1215 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>></span> | |
1216 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1217 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1218 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1219 | ||
1220 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1221 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1222 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1223 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1224 | <span class=special>};</span> | |
1225 | </pre></blockquote> | |
1226 | ||
1227 | <p> | |
1228 | <code>Pred0</code>, ... , <code>Predn</code> are the types of the equality | |
1229 | binary predicates stored by <code>composite_key_equal_to</code>. Each of these predicates | |
1230 | must be <code>CopyConstructible</code> and <code>CopyAssignable</code>. At least an | |
1231 | equality predicate must be provided. The maximum number of equality predicates of | |
1232 | a <code>composite_key_equal_to</code> instantiation is implementation defined. | |
1233 | <code>composite_key_equal_to</code> is | |
1234 | <code>CopyConstructible</code> and <code>CopyAssignable</code>. | |
1235 | It is also <code>DefaultConstructible</code> | |
1236 | if each <code>Predi</code> is <code>DefaultConstructible</code> in its turn. | |
1237 | </p> | |
1238 | ||
1239 | <p> | |
1240 | Note that formally it is not required that the <code>Predi</code> types | |
1241 | behave as equality predicates in any definite way. However, the | |
1242 | semantics of <code>composite_key_equal_to</code> is well defined if this | |
1243 | is the case, as explained in the section on the | |
1244 | <a href="#ckey_result_semantics">semantics of <code>composite_key_result</code></a>. | |
1245 | </p> | |
1246 | ||
1247 | <h4>Notation</h4> | |
1248 | ||
1249 | <p> | |
1250 | In what follows we use the same <a href="#ckey_result_notation">notation</a> | |
1251 | introduced for <code>composite_key_result</code>. | |
1252 | ||
1253 | <h4><code>composite_key_equal_to</code> members</h4> | |
1254 | ||
1255 | <code>composite_key_equal_to(<br> | |
1256 | const Pred0& p0=Pred0(),<br> | |
1257 | ...<br> | |
1258 | const Predn& pn=Predn()); | |
1259 | </code> | |
1260 | ||
1261 | <blockquote> | |
1262 | <b>Effects:</b> Constructs a <code>composite_key_equal_to</code> that stores | |
1263 | copies of the equality predicates supplied. | |
1264 | </blockquote> | |
1265 | ||
1266 | <code>composite_key_equal_to(const key_eq_tuple& x);</code> | |
1267 | ||
1268 | <blockquote> | |
1269 | <b>Effects:</b> Constructs a <code>composite_key_equal_to</code> that stores | |
1270 | copies of the equality predicate objects supplied in <code>x</code>. | |
1271 | </blockquote> | |
1272 | ||
1273 | <code>const key_eq_tuple& key_eqs()const;</code> | |
1274 | ||
1275 | <blockquote> | |
1276 | <b>Returns:</b> a constant reference to a tuple holding the | |
1277 | equality predicate objects internally stored by the | |
1278 | <code>composite_key_equal_to</code>. | |
1279 | </blockquote> | |
1280 | ||
1281 | <code>key_eq_tuple& key_eqs();</code> | |
1282 | ||
1283 | <blockquote> | |
1284 | <b>Returns:</b> a reference to a tuple holding the | |
1285 | equality predicate objects internally stored by the | |
1286 | <code>composite_key_equal_to</code>. | |
1287 | </blockquote> | |
1288 | ||
1289 | <code> | |
1290 | template<typename CompositeKey1,typename CompositeKey2><br> | |
1291 | bool operator()(<br> | |
1292 | const composite_key_result<CompositeKey1> & x,<br> | |
1293 | const composite_key_result<CompositeKey2> & y)const;<br> | |
1294 | template<typename CompositeKey,typename Values...><br> | |
1295 | bool operator()(<br> | |
1296 | const composite_key_result<CompositeKey>& x,<br> | |
1297 | const std::tuple<Values...>& y)const;<br> | |
1298 | template<typename CompositeKey,typename Values...><br> | |
1299 | bool operator()(<br> | |
1300 | const std::tuple<Values...>& x,<br> | |
1301 | const composite_key_result<CompositeKey>& y)const;<br> | |
1302 | template<typename CompositeKey,typename Value0,...,typename Valuen><br> | |
1303 | bool operator()(<br> | |
1304 | const composite_key_result<CompositeKey>& x,<br> | |
1305 | const boost::tuple<Value0,...,Valuen>& y)const;<br> | |
1306 | template<typename Value0,...,typename Valuen,typename CompositeKey><br> | |
1307 | bool operator()(<br> | |
1308 | const boost::tuple<Value0,...,Valuen>& x,<br> | |
1309 | const composite_key_result<CompositeKey>& y)const;<br> | |
1310 | </code> | |
1311 | ||
1312 | <blockquote> | |
1313 | <b>Requires:</b> <code>length(x)==length(y)</code>. The expressions | |
1314 | <code>key_eqs().get<i>()(x<sub>i</sub>,y<sub>i</sub>)</code> and | |
1315 | <code>key_eqs().get<i>()(y<sub>i</sub>,x<sub>i</sub>)</code> | |
1316 | are valid for all <code>i</code> in <code>[0,length(x))</code>.<br> | |
1317 | <b>Returns:</b> <code>true</code> if and only | |
1318 | <blockquote> | |
1319 | <code>key_eqs().get<i>()(x<sub>i</sub>,y<sub>i</sub>)</code> | |
1320 | for all <code>i</code> in <code>[0,length(x))</code>.<br> | |
1321 | </blockquote> | |
1322 | <b>Complexity:</b> No more key extraction operations and comparisons | |
1323 | are performed than those necessary for the evaluation of the expression above, | |
1324 | starting at <code>i==0</code>. The evaluation is short-circuited as soon as | |
1325 | the result is determined to be <code>false</code>. | |
1326 | </blockquote> | |
1327 | ||
1328 | <h4><a name="composite_key_result_equal_to">Class template | |
1329 | <code>composite_key_result_equal_to</code></a></h4> | |
1330 | ||
1331 | <p> | |
1332 | Deprecated. Use <code>std::equal_to<CompositeKeyResult></code> instead. | |
1333 | </p> | |
1334 | ||
1335 | <h4><a name="equal_to_composite_key_result">Specialization of | |
1336 | <code>std::equal_to</code> for <code>composite_key</code> results</a></h4> | |
1337 | ||
1338 | <p> | |
1339 | <code>std::equal_to<CompositeKeyResult></code>, with <code>CompositeKeyResult</code> | |
1340 | an instantiation of <code>composite_key_result</code>, | |
1341 | behaves as a particularization of | |
1342 | <code>composite_key_equal_to</code> where all the comparison predicates supplied | |
1343 | are instantiations of <code>std::equal_to</code>. | |
1344 | </p> | |
1345 | ||
1346 | <blockquote><pre> | |
1347 | <span class=keyword>namespace</span> <span class=identifier>std</span><span class=special>{</span> | |
1348 | ||
1349 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1350 | <span class=keyword>struct</span> <span class=identifier>equal_to</span><span class=special><</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>></span> <span class=special>></span> | |
1351 | <span class=special>{</span> | |
1352 | <span class=keyword>typedef</span> | |
1353 | <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span> | |
1354 | <span class=identifier>CompositeKey</span><span class=special>></span> <span class=identifier>first_argument_type</span><span class=special>;</span> | |
1355 | <span class=keyword>typedef</span> <span class=identifier>first_argument_type</span> <span class=identifier>second_argument_type</span><span class=special>;</span> | |
1356 | <span class=keyword>typedef</span> <span class=keyword>bool</span> <span class=identifier>result_type</span><span class=special>;</span> | |
1357 | ||
1358 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey1</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey2</span><span class=special>></span> | |
1359 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1360 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey1</span><span class=special>></span> <span class=special>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1361 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey2</span><span class=special>></span> <span class=special>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1362 | ||
1363 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1364 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1365 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1366 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1367 | ||
1368 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1369 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1370 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1371 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1372 | ||
1373 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>></span> | |
1374 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1375 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1376 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1377 | ||
1378 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1379 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1380 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1381 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1382 | <span class=special>};</span> | |
1383 | ||
1384 | <span class=special>}</span> <span class=comment>// namespace std</span> | |
1385 | </pre></blockquote> | |
1386 | ||
1387 | <p> | |
1388 | <code>CompositeKeyResult</code> must be an instantiation of | |
1389 | <code>composite_key_result</code> for some type | |
1390 | <code>composite_key<KeyFromValue0,...,KeyFromValuen></code>. | |
1391 | <code>std::equal:to<CompositeKeyResult>::operator()</code> is | |
1392 | then equivalent to | |
1393 | <code>composite_key_equal_to<Pred0,...,Predn>::operator()</code>, taking | |
1394 | <blockquote> | |
1395 | <code>Predi = std::equal_to<KeyFromValuei::result_type></code> for all | |
1396 | <code>i = 0,...,n</code>. | |
1397 | </blockquote> | |
1398 | </p> | |
1399 | ||
1400 | <p> | |
1401 | In addition to the requirements on <code>Predi</code> imposed by | |
1402 | <code>composite_key_equal_to</code>, each of these types must be | |
1403 | <code>DefaultConstructible</code>. <code>std::equal_to<CompositeKeyResult></code> | |
1404 | is <code>DefaultConstructible</code>, <code>CopyConstructible</code> and | |
1405 | <code>CopyAssignable</code>. | |
1406 | </p> | |
1407 | ||
1408 | <h3><a name="ckey_result_comparison">Comparison</a></h3> | |
1409 | ||
1410 | <h4><a name="composite_key_compare">Class template | |
1411 | <code>composite_key_compare</code></a></h4> | |
1412 | ||
1413 | <p> | |
1414 | <code>composite_key_compare</code> compares <code>composite_key_result</code> | |
1415 | instantiations between them and with tuples of values using an internally stored | |
1416 | collection of elementary comparison predicates. | |
1417 | </p> | |
1418 | ||
1419 | <blockquote><pre> | |
1420 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Compare0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Comparen</span><span class=special>></span> | |
1421 | <span class=keyword>struct</span> <span class=identifier>composite_key_compare</span> | |
1422 | <span class=special>{</span> | |
1423 | <span class=keyword>typedef</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Compare0</span><span class=special>,...,</span><span class=identifier>Comparen</span><span class=special>></span> <span class=identifier>key_comp_tuple</span><span class=special>;</span> | |
1424 | ||
1425 | <span class=identifier>composite_key_compare</span><span class=special>(</span> | |
1426 | <span class=keyword>const</span> <span class=identifier>Compare0</span><span class=special>&</span> <span class=identifier>c0</span><span class=special>=</span><span class=identifier>Compare0</span><span class=special>(),</span> | |
1427 | <span class=special>...</span> | |
1428 | <span class=keyword>const</span> <span class=identifier>Comparen</span><span class=special>&</span> <span class=identifier>cn</span><span class=special>=</span><span class=identifier>Comparen</span><span class=special>());</span> | |
1429 | ||
1430 | <span class=identifier>composite_key_compare</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>key_comp_tuple</span><span class=special>&</span> <span class=identifier>x</span><span class=special>);</span> | |
1431 | ||
1432 | <span class=keyword>const</span> <span class=identifier>key_comp_tuple</span><span class=special>&</span> <span class=identifier>key_comps</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span> | |
1433 | <span class=identifier>key_comp_tuple</span><span class=special>&</span> <span class=identifier>key_comps</span><span class=special>()</span><span class=special>;</span> | |
1434 | ||
1435 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey1</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey2</span><span class=special>></span> | |
1436 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1437 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey1</span><span class=special>></span> <span class=special>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1438 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey2</span><span class=special>></span> <span class=special>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1439 | ||
1440 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1441 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1442 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1443 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1444 | ||
1445 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1446 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1447 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1448 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1449 | ||
1450 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>></span> | |
1451 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1452 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1453 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1454 | ||
1455 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1456 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1457 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1458 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1459 | ||
1460 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Value</span><span class=special>></span> | |
1461 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1462 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span><span class=keyword>const</span> <span class=identifier>Value</span><span class=special>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1463 | ||
1464 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1465 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1466 | <span class=keyword>const</span> <span class=identifier>Value</span><span class=special>&</span> <span class=identifier>x</span><span class=special>,</span><span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1467 | <span class=special>};</span> | |
1468 | </pre></blockquote> | |
1469 | ||
1470 | <p> | |
1471 | <code>Compare0</code>, ... , <code>Comparen</code> are the types of the comparison | |
1472 | binary predicates stored by <code>composite_key_compare</code>. Each of these predicates must be | |
1473 | <code>CopyConstructible</code> and <code>CopyAssignable</code>. At least a | |
1474 | comparison predicate must be provided. The maximum number of comparison predicates of | |
1475 | a <code>composite_key_compare</code> instantiation is implementation defined. | |
1476 | <code>composite_key_compare</code> is | |
1477 | <code>CopyConstructible</code> and <code>CopyAssignable</code>. | |
1478 | It is also | |
1479 | <code>DefaultConstructible</code> | |
1480 | if each <code>Comparei</code> is <code>DefaultConstructible</code> in its turn. | |
1481 | </p> | |
1482 | ||
1483 | <p> | |
1484 | Note that formally it is not required that the <code>Comparei</code> types | |
1485 | behave as comparison predicates in any definite way. However, the | |
1486 | semantics of <code>composite_key_compare</code> is well defined if this | |
1487 | is the case, as explained in the section on the | |
1488 | <a href="#ckey_result_semantics">semantics of <code>composite_key_result</code></a>. | |
1489 | </p> | |
1490 | ||
1491 | <h4>Notation</h4> | |
1492 | ||
1493 | <p> | |
1494 | In what follows we use the same <a href="#ckey_result_notation">notation</a> | |
1495 | introduced for <code>composite_key_result</code>. | |
1496 | ||
1497 | <h4><code>composite_key_compare</code> members</h4> | |
1498 | ||
1499 | <code>composite_key_compare(<br> | |
1500 | const Compare0& c0=Compare0(),<br> | |
1501 | ...<br> | |
1502 | const Comparen& cn=Comparen()); | |
1503 | </code> | |
1504 | ||
1505 | <blockquote> | |
1506 | <b>Effects:</b> Constructs a <code>composite_key_compare</code> that stores | |
1507 | copies of the comparison predicates supplied. | |
1508 | </blockquote> | |
1509 | ||
1510 | <code>composite_key_compare(const key_comp_tuple& x);</code> | |
1511 | ||
1512 | <blockquote> | |
1513 | <b>Effects:</b> Constructs a <code>composite_key_compare</code> that stores | |
1514 | copies of the comparison predicate objects supplied in <code>x</code>. | |
1515 | </blockquote> | |
1516 | ||
1517 | <code>const key_comp_tuple& key_comps()const;</code> | |
1518 | ||
1519 | <blockquote> | |
1520 | <b>Returns:</b> a constant reference to a tuple holding the | |
1521 | comparison predicate objects internally stored by the | |
1522 | <code>composite_key_compare</code>. | |
1523 | </blockquote> | |
1524 | ||
1525 | <code>key_comp_tuple& key_comps();</code> | |
1526 | ||
1527 | <blockquote> | |
1528 | <b>Returns:</b> a reference to a tuple holding the | |
1529 | comparison predicate objects internally stored by the | |
1530 | <code>composite_key_compare</code>. | |
1531 | </blockquote> | |
1532 | ||
1533 | <code> | |
1534 | template<typename CompositeKey1,typename CompositeKey2><br> | |
1535 | bool operator()(<br> | |
1536 | const composite_key_result<CompositeKey1> & x,<br> | |
1537 | const composite_key_result<CompositeKey2> & y)const;<br> | |
1538 | template<typename CompositeKey,typename... Values><br> | |
1539 | bool operator()(<br> | |
1540 | const composite_key_result<CompositeKey>& x,<br> | |
1541 | const std::tuple<Values...>& y)const;<br> | |
1542 | template<typename CompositeKey,typename... Values><br> | |
1543 | bool operator()(<br> | |
1544 | const std::tuple<Values...>& x,<br> | |
1545 | const composite_key_result<CompositeKey>& y)const;<br> | |
1546 | template<typename CompositeKey,typename Value0,...,typename Valuen><br> | |
1547 | bool operator()(<br> | |
1548 | const composite_key_result<CompositeKey>& x,<br> | |
1549 | const boost::tuple<Value0,...,Valuen>& y)const;<br> | |
1550 | template<typename Value0,...,typename Valuen,typename CompositeKey><br> | |
1551 | bool operator()(<br> | |
1552 | const boost::tuple<Value0,...,Valuen>& x,<br> | |
1553 | const composite_key_result<CompositeKey>& y)const;<br> | |
1554 | </code> | |
1555 | ||
1556 | <blockquote> | |
1557 | <b>Requires:</b> The expressions | |
1558 | <code>key_comps().get<i>()(x<sub>i</sub>,y<sub>i</sub>)</code> and | |
1559 | <code>key_comps().get<i>()(y<sub>i</sub>,x<sub>i</sub>)</code> | |
1560 | are valid for all <code>i</code> | |
1561 | in <code>[0,min(length(x),length(y)))</code>.<br> | |
1562 | <b>Returns:</b> <code>true</code> if and only if there exists some | |
1563 | <code>j</code> in the range <code>[0,min(length(x),length(y)))</code> | |
1564 | such that | |
1565 | <blockquote> | |
1566 | <code>!key_comps().get<i>()(x<sub>i</sub>,y<sub>i</sub>) && !key_comps().get<i>()(y<sub>i</sub>,x<sub>i</sub>)</code> | |
1567 | for all <code>i</code> in <code>[0,j)</code>,<br> | |
1568 | <code> key_comps().get<j>()(x<sub>j</sub>,y<sub>j</sub>)</code>. | |
1569 | </blockquote> | |
1570 | <b>Complexity:</b> No more key extraction operations and comparisons | |
1571 | are performed than those necessary for the evaluation of the expression above, | |
1572 | starting at <code>i==0</code>. The evaluation is short-circuited as soon as | |
1573 | the result is determined to be <code>false</code>. | |
1574 | </blockquote> | |
1575 | ||
1576 | <code> | |
1577 | template<typename CompositeKey,typename Value><br> | |
1578 | bool operator()(<br> | |
1579 | const composite_key_result<CompositeKey>& x,const Value& y)const; | |
1580 | </code> | |
1581 | ||
1582 | <blockquote> | |
1583 | <b>Effects:</b> | |
1584 | <blockquote><pre> | |
1585 | <span class=keyword>return</span> <span class=keyword>operator</span><span class=special>()(</span><span class=identifier>x</span><span class=special>,</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>make_tuple</span><span class=special>(</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>cref</span><span class=special>(</span><span class=identifier>y</span><span class=special>)));</span> | |
1586 | </pre></blockquote><br> | |
1587 | </blockquote> | |
1588 | ||
1589 | <code> | |
1590 | template<typename Value,typename CompositeKey><br> | |
1591 | bool operator()(<br> | |
1592 | const Value& x,const composite_key_result<CompositeKey>& y)const; | |
1593 | </code> | |
1594 | ||
1595 | <blockquote> | |
1596 | <b>Effects:</b> | |
1597 | <blockquote><pre> | |
1598 | <span class=keyword>return</span> <span class=keyword>operator</span><span class=special>()(</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>make_tuple</span><span class=special>(</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>cref</span><span class=special>(</span><span class=identifier>x</span><span class=special>)),</span><span class=identifier>y</span><span class=special>);</span> | |
1599 | </pre></blockquote><br> | |
1600 | </blockquote> | |
1601 | ||
1602 | <h4><a name="composite_key_result_less">Class template | |
1603 | <code>composite_key_result_less</code></a></h4> | |
1604 | ||
1605 | <p> | |
1606 | Deprecated. Use <code>std::less<CompositeKeyResult></code> instead. | |
1607 | </p> | |
1608 | ||
1609 | <h4><a name="composite_key_result_greater">Class template | |
1610 | <code>composite_key_result_greater</code></a></h4> | |
1611 | ||
1612 | <p> | |
1613 | Deprecated. Use <code>std::greater<CompositeKeyResult></code> instead. | |
1614 | </p> | |
1615 | ||
1616 | <h4><a name="less_composite_key_result">Specialization of <code>std::less</code> for | |
1617 | <code>composite_key</code> results</a></h4> | |
1618 | ||
1619 | <p> | |
1620 | <code>std::less<CompositeKeyResult></code>, with <code>CompositeKeyResult</code> | |
1621 | an instantiation of <code>composite_key_result</code>, behaves as a particularization of | |
1622 | <code>composite_key_compare</code> where all the comparison predicates supplied are | |
1623 | instantiations of <code>std::less</code>. | |
1624 | </p> | |
1625 | ||
1626 | <blockquote><pre> | |
1627 | <span class=keyword>namespace</span> <span class=identifier>std</span><span class=special>{</span> | |
1628 | ||
1629 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1630 | <span class=keyword>struct</span> <span class=identifier>less</span><span class=special><</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>></span> <span class=special>></span> | |
1631 | <span class=special>{</span> | |
1632 | <span class=keyword>typedef</span> | |
1633 | <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span> | |
1634 | <span class=identifier>CompositeKey</span><span class=special>></span> <span class=identifier>first_argument_type</span><span class=special>;</span> | |
1635 | <span class=keyword>typedef</span> <span class=identifier>first_argument_type</span> <span class=identifier>second_argument_type</span><span class=special>;</span> | |
1636 | <span class=keyword>typedef</span> <span class=keyword>bool</span> <span class=identifier>result_type</span><span class=special>;</span> | |
1637 | ||
1638 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey1</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey2</span><span class=special>></span> | |
1639 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1640 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey1</span><span class=special>></span> <span class=special>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1641 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey2</span><span class=special>></span> <span class=special>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1642 | ||
1643 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1644 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1645 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1646 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1647 | ||
1648 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1649 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1650 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1651 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1652 | ||
1653 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>></span> | |
1654 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1655 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1656 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1657 | ||
1658 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1659 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1660 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1661 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1662 | ||
1663 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Value</span><span class=special>></span> | |
1664 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1665 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1666 | <span class=keyword>const</span> <span class=identifier>Value</span><span class=special>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1667 | ||
1668 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1669 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1670 | <span class=keyword>const</span> <span class=identifier>Value</span><span class=special>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1671 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1672 | <span class=special>};</span> | |
1673 | ||
1674 | <span class=special>}</span> <span class=comment>// namespace std</span> | |
1675 | </pre></blockquote> | |
1676 | ||
1677 | <p> | |
1678 | <code>CompositeKeyResult</code> must be an instantiation of | |
1679 | <code>composite_key_result</code> for some type | |
1680 | <code>composite_key<KeyFromValue0,...,KeyFromValuen></code>. | |
1681 | <code>std::less<CompositeKeyResult>::operator()</code> is | |
1682 | then equivalent to | |
1683 | <code>composite_key_compare<Compare0,...,Comparen>::operator()</code>, taking | |
1684 | <blockquote> | |
1685 | <code>Comparei = std::less<KeyFromValuei::result_type></code> for all | |
1686 | <code>i = 0,...,n</code>. | |
1687 | </blockquote> | |
1688 | </p> | |
1689 | ||
1690 | <p> | |
1691 | In addition to the requirements on <code>Comparei</code> imposed by | |
1692 | <code>composite_key_compare</code>, each of these types must be | |
1693 | <code>DefaultConstructible</code>. <code>std::less<CompositeKeyResult></code> | |
1694 | is <code>CopyConstructible</code>, <code>CopyConstructible</code> | |
1695 | and <code>CopyAssignable</code>. | |
1696 | </p> | |
1697 | ||
1698 | <h4><a name="greater_composite_key_result">Specialization of <code>std::greater</code> for | |
1699 | <code>composite_key</code> results</a></h4> | |
1700 | ||
1701 | <p> | |
1702 | <code>std::greater<CompositeKeyResult></code>, with <code>CompositeKeyResult</code> | |
1703 | an instantiation of <code>composite_key_result</code>, behaves as a particularization of | |
1704 | <code>composite_key_compare</code> where all the comparison predicates supplied | |
1705 | are instantiations of <code>std::greater</code>. | |
1706 | </p> | |
1707 | ||
1708 | ||
1709 | <blockquote><pre> | |
1710 | <span class=keyword>namespace</span> <span class=identifier>std</span><span class=special>{</span> | |
1711 | ||
1712 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1713 | <span class=keyword>struct</span> <span class=identifier>greater</span><span class=special><</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>></span> <span class=special>></span> | |
1714 | <span class=special>{</span> | |
1715 | <span class=keyword>typedef</span> | |
1716 | <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span> | |
1717 | <span class=identifier>CompositeKey</span><span class=special>></span> <span class=identifier>first_argument_type</span><span class=special>;</span> | |
1718 | <span class=keyword>typedef</span> <span class=identifier>first_argument_type</span> <span class=identifier>second_argument_type</span><span class=special>;</span> | |
1719 | <span class=keyword>typedef</span> <span class=keyword>bool</span> <span class=identifier>result_type</span><span class=special>;</span> | |
1720 | ||
1721 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey1</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey2</span><span class=special>></span> | |
1722 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1723 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey1</span><span class=special>></span> <span class=special>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1724 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey2</span><span class=special>></span> <span class=special>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1725 | ||
1726 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1727 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1728 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1729 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1730 | ||
1731 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1732 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1733 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1734 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1735 | ||
1736 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>></span> | |
1737 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1738 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1739 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1740 | ||
1741 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1742 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1743 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1744 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1745 | ||
1746 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>Value</span><span class=special>></span> | |
1747 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1748 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1749 | <span class=keyword>const</span> <span class=identifier>Value</span><span class=special>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1750 | ||
1751 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1752 | <span class=keyword>bool</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1753 | <span class=keyword>const</span> <span class=identifier>Value</span><span class=special>&</span> <span class=identifier>x</span><span class=special>,</span> | |
1754 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>y</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1755 | <span class=special>};</span> | |
1756 | ||
1757 | <span class=special>}</span> <span class=comment>// namespace std</span> | |
1758 | </pre></blockquote> | |
1759 | ||
1760 | <p> | |
1761 | <code>CompositeKeyResult</code> must be an instantiation of | |
1762 | <code>composite_key_result</code> for some type | |
1763 | <code>composite_key<KeyFromValue0,...,KeyFromValuen></code>. | |
1764 | <code>std::greater<CompositeKeyResult>::operator()</code> is | |
1765 | then equivalent to | |
1766 | <code>composite_key_compare<Compare0,...,Comparen>::operator()</code>, taking | |
1767 | <blockquote> | |
1768 | <code>Comparei = std::greater<KeyFromValuei::result_type></code> for all | |
1769 | <code>i = 0,...,n</code>. | |
1770 | </blockquote> | |
1771 | </p> | |
1772 | ||
1773 | <p> | |
1774 | In addition to the requirements on <code>Comparei</code> imposed by | |
1775 | <code>composite_key_compare</code>, each of these types must be | |
1776 | <code>DefaultConstructible</code>. <code>std::greater<CompositeKeyResult></code> | |
1777 | is <code>CopyConstructible</code>, <code>CopyConstructible</code> | |
1778 | and <code>CopyAssignable</code>. | |
1779 | </p> | |
1780 | ||
1781 | <h3><a name="ckey_result_hashing">Hashing</a></h3> | |
1782 | ||
1783 | <h4><a name="composite_key_hash">Class template | |
1784 | <code>composite_key_hash</code></a></h4> | |
1785 | ||
1786 | <p> | |
1787 | <code>composite_key_hash</code> produces hash values for <code>composite_key_result</code> | |
1788 | instantiations based on a collection of elementary hash functors. | |
1789 | </p> | |
1790 | ||
1791 | <blockquote><pre> | |
1792 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Hash0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Hashn</span><span class=special>></span> | |
1793 | <span class=keyword>struct</span> <span class=identifier>composite_key_hash</span> | |
1794 | <span class=special>{</span> | |
1795 | <span class=keyword>typedef</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Hash0</span><span class=special>,...,</span><span class=identifier>Hashn</span><span class=special>></span> <span class=identifier>key_hasher_tuple</span><span class=special>;</span> | |
1796 | ||
1797 | <span class=identifier>composite_key_hash</span><span class=special>(</span> | |
1798 | <span class=keyword>const</span> <span class=identifier>Hash0</span><span class=special>&</span> <span class=identifier>h0</span><span class=special>=</span><span class=identifier>Hash0</span><span class=special>(),</span> | |
1799 | <span class=special>...</span> | |
1800 | <span class=keyword>const</span> <span class=identifier>Hashn</span><span class=special>&</span> <span class=identifier>hn</span><span class=special>=</span><span class=identifier>Hashn</span><span class=special>());</span> | |
1801 | ||
1802 | <span class=identifier>composite_key_hash</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>key_hasher_tuple</span><span class=special>&</span> <span class=identifier>x</span><span class=special>);</span> | |
1803 | ||
1804 | <span class=keyword>const</span> <span class=identifier>key_hasher_tuple</span><span class=special>&</span> <span class=identifier>key_hash_functions</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span> | |
1805 | <span class=identifier>key_hasher_tuple</span><span class=special>&</span> <span class=identifier>key_hash_functions</span><span class=special>()</span><span class=special>;</span> | |
1806 | ||
1807 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1808 | <span class=identifier>std</span><span class=special>::</span><span class=identifier>size_t</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1809 | <span class=keyword>const</span> <span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1810 | ||
1811 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1812 | <span class=identifier>std</span><span class=special>::</span><span class=identifier>size_t</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1813 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1814 | ||
1815 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>></span> | |
1816 | <span class=identifier>std</span><span class=special>::</span><span class=identifier>size_t</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1817 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1818 | <span class=special>};</span> | |
1819 | </pre></blockquote> | |
1820 | ||
1821 | <p> | |
1822 | <code>Hash0</code>, ... , <code>Hashn</code> are the types of the hash unary function objects | |
1823 | stored by <code>composite_key_hash</code>. Each of these objects | |
1824 | must be <code>CopyConstructible</code> and <code>CopyAssignable</code> | |
1825 | and return a value of type <code>std::size_t</code> in the range | |
1826 | [0, <code>std::numeric_limits<std::size_t>::max())</code>). | |
1827 | At least a hash functor must be provided. The maximum number of hash functors of | |
1828 | a <code>composite_key_hash</code> instantiation is implementation defined. | |
1829 | <code>composite_key_hash</code> is | |
1830 | <code>CopyConstructible</code> and <code>CopyAssignable</code>. | |
1831 | It is also <code>DefaultConstructible</code> | |
1832 | if each <code>Hashi</code> is <code>DefaultConstructible</code> in its turn. | |
1833 | </p> | |
1834 | ||
1835 | <h4>Notation</h4> | |
1836 | ||
1837 | <p> | |
1838 | In what follows we use the same <a href="#ckey_result_notation">notation</a> | |
1839 | introduced for <code>composite_key_result</code>. | |
1840 | ||
1841 | <h4><code>composite_key_hash</code> members</h4> | |
1842 | ||
1843 | <code>composite_key_hash(<br> | |
1844 | const Hash0& h0=Hash0(),<br> | |
1845 | ...<br> | |
1846 | const Hashn& hn=Hashn()); | |
1847 | </code> | |
1848 | ||
1849 | <blockquote> | |
1850 | <b>Effects:</b> Constructs a <code>composite_key_hash</code> that stores | |
1851 | copies of the hash functors supplied. | |
1852 | </blockquote> | |
1853 | ||
1854 | <code>composite_key_hash(const key_hasher_tuple& x);</code> | |
1855 | ||
1856 | <blockquote> | |
1857 | <b>Effects:</b> Constructs a <code>composite_key_hash</code> that stores | |
1858 | copies of the hash functors supplied in <code>x</code>. | |
1859 | </blockquote> | |
1860 | ||
1861 | <code>const key_hasher_tuple& key_hash_functions()const;</code> | |
1862 | ||
1863 | <blockquote> | |
1864 | <b>Returns:</b> a constant reference to a tuple holding the | |
1865 | hash functors internally stored by the | |
1866 | <code>composite_key_hash</code>. | |
1867 | </blockquote> | |
1868 | ||
1869 | <code>key_hasher_tuple& key_hash_functions();</code> | |
1870 | ||
1871 | <blockquote> | |
1872 | <b>Returns:</b> a reference to a tuple holding the | |
1873 | hash functors internally stored by the | |
1874 | <code>composite_key_hash</code>. | |
1875 | </blockquote> | |
1876 | ||
1877 | <code> | |
1878 | template<typename CompositeKey><br> | |
1879 | bool operator()(<br> | |
1880 | const composite_key_result<CompositeKey>& x)const;<br> | |
1881 | template<typename... Values><br> | |
1882 | bool operator()(<br> | |
1883 | const std::tuple<Values...>& x)const;<br> | |
1884 | template<typename Value0,...,typename Valuen><br> | |
1885 | bool operator()(<br> | |
1886 | const boost::tuple<Value0,...,Valuen>& x)const; | |
1887 | </code> | |
1888 | ||
1889 | <blockquote> | |
1890 | <b>Requires:</b> <code>length(x)==length(key_hash_functions())</code>. | |
1891 | The expression | |
1892 | <code>key_hash_functions().get<i>()(x<sub>i</sub>)</code> | |
1893 | is valid for all <code>i</code> in <code>[0,length(x))</code>. | |
1894 | <br> | |
1895 | <b>Returns:</b> A value in the range | |
1896 | <code>[0, std::numeric_limits<std::size_t>::max())</code> that | |
1897 | solely depends on the numerical tuple | |
1898 | <blockquote> | |
1899 | (<code>key_hash_functions().get<0>()(x<sub>0</sub>)</code>, ... , | |
1900 | <code>key_hash_functions().get<N>()(x<sub>N</sub>)</code>), | |
1901 | with <code>N=length(x)-1</code>. | |
1902 | </blockquote> | |
1903 | </blockquote> | |
1904 | ||
1905 | <h4><a name="composite_key_result_hash">Class template | |
1906 | <code>composite_key_result_hash</code></a></h4> | |
1907 | ||
1908 | <p> | |
1909 | Deprecated. Use <code>boost::hash<CompositeKeyResult></code> instead. | |
1910 | </p> | |
1911 | ||
1912 | <h4><a name="hash_composite_key_result">Specialization of | |
1913 | <a href="../../../functional/hash/index.html"><code>boost::hash</code></a> | |
1914 | for <code>composite_key</code> results</a></h4> | |
1915 | ||
1916 | <p> | |
1917 | <code>boost::hash<CompositeKeyResult></code>, with <code>CompositeKeyResult</code> | |
1918 | an instantiation of <code>composite_key_result</code>, behaves as a particularization of | |
1919 | <code>composite_key_hash</code> where all the hash functors supplied | |
1920 | are instantiations of | |
1921 | <a href="../../../functional/hash/index.html"><code>boost::hash</code></a>. | |
1922 | </p> | |
1923 | ||
1924 | <blockquote><pre> | |
1925 | <span class=keyword>namespace</span> <span class=identifier>boost</span><span class=special>{</span> | |
1926 | ||
1927 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1928 | <span class=keyword>struct</span> <span class=identifier>hash</span><span class=special><</span><span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>></span> <span class=special>></span> | |
1929 | <span class=special>{</span> | |
1930 | <span class=keyword>typedef</span> <span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>></span> <span class=identifier>argument_type</span><span class=special>;</span> | |
1931 | <span class=keyword>typedef</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>size_t</span> <span class=identifier>result_type</span><span class=special>;</span> | |
1932 | ||
1933 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompositeKey</span><span class=special>></span> | |
1934 | <span class=identifier>std</span><span class=special>::</span><span class=identifier>size_t</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1935 | <span class=keyword>const</span> <span class=identifier>multi_index</span><span class=special>::</span><span class=identifier>composite_key_result</span><span class=special><</span><span class=identifier>CompositeKey</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1936 | ||
1937 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span><span class=special>...</span> <span class=identifier>Values</span><span class=special>></span> | |
1938 | <span class=identifier>std</span><span class=special>::</span><span class=identifier>size_t</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1939 | <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Values</span><span class=special>...>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1940 | ||
1941 | <span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Value0</span><span class=special>,...,</span><span class=keyword>typename</span> <span class=identifier>Valuen</span><span class=special>></span> | |
1942 | <span class=identifier>std</span><span class=special>::</span><span class=identifier>size_t</span> <span class=keyword>operator</span><span class=special>()(</span> | |
1943 | <span class=keyword>const</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>Value0</span><span class=special>,...,</span><span class=identifier>Valuen</span><span class=special>>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span> | |
1944 | <span class=special>};</span> | |
1945 | ||
1946 | <span class=special>}</span> <span class=comment>// namespace boost</span> | |
1947 | </pre></blockquote> | |
1948 | ||
1949 | <p> | |
1950 | <code>CompositeKeyResult</code> must be an instantiation of | |
1951 | <code>composite_key_result</code> for some type | |
1952 | <code>composite_key<KeyFromValue0,...,KeyFromValuen></code>. | |
1953 | <code>boost::hash<CompositeKeyResult>::operator()</code> is | |
1954 | then equivalent to | |
1955 | <code>composite_key_hash<Hash0,...,Hashn>::operator()</code>, taking | |
1956 | <blockquote> | |
1957 | <code>Hashi = boost::hash<KeyFromValuei::result_type></code> for all | |
1958 | <code>i = 0,...,n</code>. | |
1959 | </blockquote> | |
1960 | </p> | |
1961 | ||
1962 | <p> | |
1963 | In addition to the requirements on <code>Hashi</code> imposed by | |
1964 | <code>composite_key_hash</code>, each of these types must be | |
1965 | <code>DefaultConstructible</code>. <code>boost::hash<CompositeKeyResult></code> is | |
1966 | <code>DefaultConstructible</code>, <code>CopyConstructible</code> | |
1967 | and <code>CopyAssignable</code>. | |
1968 | </p> | |
1969 | ||
1970 | <h3><a name="ckey_result_semantics">Semantics of | |
1971 | <code>composite_key_result</code></a></h3> | |
1972 | ||
1973 | <p> | |
1974 | The design of equality, comparison and hash operations for | |
1975 | <code>composite_key_result</code> objects is based on the following rationale: | |
1976 | a <code>composite_key_result</code> is regarded as a "virtual" tuple, each | |
1977 | of its elements being the result of the corresponding elementary | |
1978 | key extractor. Accordingly, any given operation resolves to a | |
1979 | combination of the corresponding elementwise operations. | |
1980 | This mapping preserves the fundamental properties of the elementary operations | |
1981 | involved; for instance, it defines a true equivalence relation if the | |
1982 | basic predicates induce equivalence relations themselves. | |
1983 | We can state these facts in a formal way as follows. | |
1984 | </p> | |
1985 | ||
1986 | <p> | |
1987 | Consider an instantiation of <code>composite_key_equal_to</code> | |
1988 | with types <code>Pred0</code>, ... , <code>Predn</code> such that each | |
1989 | <code>Predi</code> induces an equivalence relation on a certain type <code>Ti</code>, | |
1990 | and let <code>CompositeKey</code> be a type of the form | |
1991 | <code>composite_key<Value,KeyFromValue0,...,KeyFromValuej></code>, | |
1992 | with <code>j <= n</code>, such that | |
1993 | <blockquote> | |
1994 | <code>KeyFromValuei::result_type = Ti</code>, for all <code>i = 0,...,j</code>. | |
1995 | </blockquote> | |
1996 | Then, <code>composite_key_equal_to</code> induces an equivalence relation | |
1997 | on elements of type <code>composite_key_result<CompositeKey></code>; | |
1998 | such two objects are equivalent if all its elementary key extractor values | |
1999 | are also equivalent. Additionally, given an instantiation | |
2000 | <code>composite_key_hash<Hash0,...,Hashj></code>, the following types are | |
2001 | <a href="hash_indices.html#lookup"><code>Compatible Keys</code></a> of | |
2002 | (<code>composite_key_hash</code>, <code>composite_key_equal_to</code>) | |
2003 | with respect to <code>composite_key_result<CompositeKey></code>: | |
2004 | <blockquote> | |
2005 | <code>tuple<Q0,...,Qj></code>,<br> | |
2006 | <code>composite_key_result<composite_key<K0,...,Kj> ></code>, with | |
2007 | <code>Ki::result_type = Qi</code> for all <code>i = 0,...,j</code>. | |
2008 | </blockquote> | |
2009 | provided that each <code>Qi</code> is either <code>Ti</code> or a | |
2010 | <a href="hash_indices.html#lookup"><code>Compatible Key</code></a> | |
2011 | of (<code>Hashi</code>, <code>Predi</code>).</p> | |
2012 | ||
2013 | <p> | |
2014 | As for comparison, consider an instantiation of <code>composite_key_compare</code> | |
2015 | with types <code>Compare0</code>, ... , <code>Comparen</code> such that each | |
2016 | <code>Comparei</code> induces a strict weak ordering | |
2017 | on the type <code>Ti</code>. Then, for a | |
2018 | <code>CompositeKey</code> type defined in the same manner as above, | |
2019 | <code>composite_key_compare</code> induces a strict weak ordering on elements of type | |
2020 | <code>composite_key_result<CompositeKey></code>, and the order induced | |
2021 | is lexicographical. Also, the following types are | |
2022 | <a href="ord_indices.html#set_operations"><code>Compatible Keys</code></a> of | |
2023 | <code>composite_key_compare</code> with respect to | |
2024 | <code>composite_key_result<CompositeKey></code>: | |
2025 | <blockquote> | |
2026 | <code>tuple<Q0,...,Qk></code>, <code>k <= n</code><br> | |
2027 | <code>composite_key_result<composite_key<K0,...,Kk> ></code>, with | |
2028 | <code>Ki::result_type = Qi</code> for all <code>i = 0,...,k</code>. | |
2029 | </blockquote> | |
2030 | provided that | |
2031 | <ul> | |
2032 | <li>for <code>i = 0,...,min(j,k)-1</code>, <code>Qi</code> is either <code>Ti</code> | |
2033 | or <i>not coarser</i> than <code>Ti</code> (<code>Qi</code> is a | |
2034 | <a href="ord_indices.html#set_operations"><code>Compatible Key</code></a> | |
2035 | of <code>Comparei</code> and there are no two distinct elements of | |
2036 | <code>Ti</code> equivalent to one single element of <code>Qi</code>); | |
2037 | </li> | |
2038 | <li> | |
2039 | <code>Qm</code> (with <code>m = min(j,k)</code>) is either <code>Tm</code> or a | |
2040 | <a href="ord_indices.html#set_operations"><code>Compatible Key</code></a> | |
2041 | of <code>Comparem</code>. | |
2042 | </li> | |
2043 | </ul> | |
2044 | ||
2045 | In this case, the comparison is done | |
2046 | lexicographically only on the first <code>1+min(j,k)</code> elements. | |
2047 | </p> | |
2048 | ||
2049 | <p> | |
2050 | Analogous properties hold for the equality and comparison operators | |
2051 | of <code>composite_key_result</code>. Note, however, | |
2052 | that equality is only defined for objects of the same length, whilst | |
2053 | comparison takes the minimum length of the operands considered. | |
2054 | Therefore, the equivalence classes induced by <code>x==y</code> are | |
2055 | subsets of those associated to <code>!(x<y)&&!(y<x)</code>. | |
2056 | </p> | |
2057 | ||
2058 | <hr> | |
2059 | ||
2060 | <div class="prev_link"><a href="rnd_indices.html"><img src="../prev.gif" alt="random access indices" border="0"><br> | |
2061 | Random access indices | |
2062 | </a></div> | |
2063 | <div class="up_link"><a href="index.html"><img src="../up.gif" alt="Boost.MultiIndex reference" border="0"><br> | |
2064 | Boost.MultiIndex reference | |
2065 | </a></div> | |
2066 | <div class="next_link"><a href="../compiler_specifics.html"><img src="../next.gif" alt="compiler specifics" border="0"><br> | |
2067 | Compiler specifics | |
2068 | </a></div><br clear="all" style="clear: all;"> | |
2069 | ||
2070 | <br> | |
2071 | ||
2072 | <p>Revised November 24th 2015</p> | |
2073 | ||
2074 | <p>© Copyright 2003-2015 Joaquín M López Muñoz. | |
2075 | Distributed under the Boost Software | |
2076 | License, Version 1.0. (See accompanying file <a href="../../../../LICENSE_1_0.txt"> | |
2077 | LICENSE_1_0.txt</a> or copy at <a href="http://www.boost.org/LICENSE_1_0.txt"> | |
2078 | http://www.boost.org/LICENSE_1_0.txt</a>) | |
2079 | </p> | |
2080 | ||
2081 | </body> | |
2082 | </html> |