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24 | </div> | |
25 | <div class="section boost_icl_interface_required_concepts" lang="en"> | |
26 | <div class="titlepage"><div><div><h3 class="title"> | |
27 | <a name="boost_icl.interface.required_concepts"></a><a class="link" href="required_concepts.html" title="Required Concepts">Required Concepts</a> | |
28 | </h3></div></div></div> | |
29 | <p> | |
30 | There are uniform requirements for the template parameters across <span class="bold"><strong>icl's</strong></span> class templates. The template parameters can | |
31 | be grouped with respect to those requirements. | |
32 | </p> | |
33 | <div class="informaltable"><table class="table"> | |
34 | <colgroup> | |
35 | <col> | |
36 | <col> | |
37 | <col> | |
38 | <col> | |
39 | <col> | |
40 | <col> | |
41 | </colgroup> | |
42 | <thead><tr> | |
43 | <th> | |
44 | <p> | |
45 | </p> | |
46 | </th> | |
47 | <th> | |
48 | <p> | |
49 | used in | |
50 | </p> | |
51 | </th> | |
52 | <th> | |
53 | <p> | |
54 | Kind | |
55 | </p> | |
56 | </th> | |
57 | <th> | |
58 | <p> | |
59 | Parameter | |
60 | </p> | |
61 | </th> | |
62 | <th> | |
63 | <p> | |
64 | Instance | |
65 | </p> | |
66 | </th> | |
67 | <th> | |
68 | <p> | |
69 | Description | |
70 | </p> | |
71 | </th> | |
72 | </tr></thead> | |
73 | <tbody> | |
74 | <tr> | |
75 | <td> | |
76 | <p> | |
77 | Domain order | |
78 | </p> | |
79 | </td> | |
80 | <td> | |
81 | <p> | |
82 | <code class="computeroutput"><span class="identifier">Intervals</span><span class="special">,</span> | |
83 | <span class="identifier">Sets</span><span class="special">,</span> | |
84 | <span class="identifier">Maps</span></code> | |
85 | </p> | |
86 | </td> | |
87 | <td> | |
88 | <p> | |
89 | <code class="computeroutput"><span class="keyword">typename</span></code> | |
90 | </p> | |
91 | </td> | |
92 | <td> | |
93 | <p> | |
94 | <code class="computeroutput"><span class="identifier">DomainT</span></code> | |
95 | </p> | |
96 | </td> | |
97 | <td> | |
98 | <p> | |
99 | </p> | |
100 | </td> | |
101 | <td> | |
102 | <p> | |
103 | For the type <code class="computeroutput"><span class="identifier">DomainT</span></code> | |
104 | of key elements <code class="computeroutput"><span class="special">...</span></code> | |
105 | </p> | |
106 | </td> | |
107 | </tr> | |
108 | <tr> | |
109 | <td> | |
110 | <p> | |
111 | </p> | |
112 | </td> | |
113 | <td> | |
114 | <p> | |
115 | </p> | |
116 | </td> | |
117 | <td> | |
118 | <p> | |
119 | <code class="computeroutput"><span class="keyword">template</span></code> | |
120 | </p> | |
121 | </td> | |
122 | <td> | |
123 | <p> | |
124 | <code class="computeroutput"><span class="identifier">Compare</span></code> | |
125 | </p> | |
126 | </td> | |
127 | <td> | |
128 | <p> | |
129 | <code class="computeroutput"><span class="identifier">Compare</span><span class="special"><</span><span class="identifier">DomainT</span><span class="special">></span></code> | |
130 | </p> | |
131 | </td> | |
132 | <td> | |
133 | <p> | |
134 | <code class="computeroutput"><span class="special">...</span></code> there is an order | |
135 | <code class="computeroutput"><span class="identifier">Compare</span></code> | |
136 | </p> | |
137 | </td> | |
138 | </tr> | |
139 | <tr> | |
140 | <td> | |
141 | <p> | |
142 | Interval type | |
143 | </p> | |
144 | </td> | |
145 | <td> | |
146 | <p> | |
147 | <code class="computeroutput"><span class="identifier">interval_sets</span><span class="special">/</span><span class="identifier">maps</span></code> | |
148 | </p> | |
149 | </td> | |
150 | <td> | |
151 | <p> | |
152 | <code class="computeroutput"><span class="keyword">typename</span></code> | |
153 | </p> | |
154 | </td> | |
155 | <td> | |
156 | <p> | |
157 | <code class="computeroutput"><span class="identifier">IntervalT</span></code> | |
158 | </p> | |
159 | </td> | |
160 | <td> | |
161 | <p> | |
162 | </p> | |
163 | </td> | |
164 | <td> | |
165 | <p> | |
166 | <code class="computeroutput"><span class="special">...</span></code> the <code class="computeroutput"><span class="identifier">IntervalT</span></code> parameter has to use | |
167 | the same element type and order. | |
168 | </p> | |
169 | </td> | |
170 | </tr> | |
171 | <tr> | |
172 | <td> | |
173 | <p> | |
174 | Codomain aggregation | |
175 | </p> | |
176 | </td> | |
177 | <td> | |
178 | <p> | |
179 | <code class="computeroutput"><span class="identifier">Maps</span></code> | |
180 | </p> | |
181 | </td> | |
182 | <td> | |
183 | <p> | |
184 | <code class="computeroutput"><span class="keyword">typename</span></code> | |
185 | </p> | |
186 | </td> | |
187 | <td> | |
188 | <p> | |
189 | <code class="computeroutput"><span class="identifier">CodomainT</span></code> | |
190 | </p> | |
191 | </td> | |
192 | <td> | |
193 | <p> | |
194 | </p> | |
195 | </td> | |
196 | <td> | |
197 | <p> | |
198 | For the type <code class="computeroutput"><span class="identifier">CodomainT</span></code> | |
199 | of associated values <code class="computeroutput"><span class="special">...</span></code> | |
200 | </p> | |
201 | </td> | |
202 | </tr> | |
203 | <tr> | |
204 | <td> | |
205 | <p> | |
206 | </p> | |
207 | </td> | |
208 | <td> | |
209 | <p> | |
210 | </p> | |
211 | </td> | |
212 | <td> | |
213 | <p> | |
214 | <code class="computeroutput"><span class="keyword">template</span></code> | |
215 | </p> | |
216 | </td> | |
217 | <td> | |
218 | <p> | |
219 | <code class="computeroutput"><span class="identifier">Combine</span></code> | |
220 | </p> | |
221 | </td> | |
222 | <td> | |
223 | <p> | |
224 | <code class="computeroutput"><span class="identifier">Combine</span><span class="special"><</span><span class="identifier">CodomainT</span><span class="special">></span></code> | |
225 | </p> | |
226 | </td> | |
227 | <td> | |
228 | <p> | |
229 | <code class="computeroutput"><span class="special">...</span></code> there is a binary | |
230 | functor <code class="computeroutput"><span class="identifier">Combine</span><span class="special"><</span><span class="identifier">CodomainT</span><span class="special">>()</span></code> | |
231 | to combine them | |
232 | </p> | |
233 | </td> | |
234 | </tr> | |
235 | <tr> | |
236 | <td> | |
237 | <p> | |
238 | </p> | |
239 | </td> | |
240 | <td> | |
241 | <p> | |
242 | </p> | |
243 | </td> | |
244 | <td> | |
245 | <p> | |
246 | </p> | |
247 | </td> | |
248 | <td> | |
249 | <p> | |
250 | </p> | |
251 | </td> | |
252 | <td> | |
253 | <p> | |
254 | <code class="computeroutput"><span class="identifier">Inverse</span><span class="special"><</span><span class="identifier">Combine</span><span class="special"><</span><span class="identifier">CodomainT</span><span class="special">>></span></code> | |
255 | </p> | |
256 | </td> | |
257 | <td> | |
258 | <p> | |
259 | <code class="computeroutput"><span class="special">...</span></code> and implicitly an | |
260 | <code class="computeroutput"><span class="identifier">Inverse</span></code> functor to | |
261 | inversely combine them. | |
262 | </p> | |
263 | </td> | |
264 | </tr> | |
265 | <tr> | |
266 | <td> | |
267 | <p> | |
268 | </p> | |
269 | </td> | |
270 | <td> | |
271 | <p> | |
272 | </p> | |
273 | </td> | |
274 | <td> | |
275 | <p> | |
276 | <code class="computeroutput"><span class="keyword">template</span></code> | |
277 | </p> | |
278 | </td> | |
279 | <td> | |
280 | <p> | |
281 | <code class="computeroutput"><span class="identifier">Section</span></code> | |
282 | </p> | |
283 | </td> | |
284 | <td> | |
285 | <p> | |
286 | <code class="computeroutput"><span class="identifier">Section</span><span class="special"><</span><span class="identifier">CodomainT</span><span class="special">></span></code> | |
287 | </p> | |
288 | </td> | |
289 | <td> | |
290 | <p> | |
291 | Intersection is propagated to CodomainT values via functor <code class="computeroutput"><span class="identifier">Section</span><span class="special"><</span><span class="identifier">CodomainT</span><span class="special">>()</span></code> | |
292 | </p> | |
293 | </td> | |
294 | </tr> | |
295 | <tr> | |
296 | <td> | |
297 | <p> | |
298 | Memory allocation | |
299 | </p> | |
300 | </td> | |
301 | <td> | |
302 | <p> | |
303 | <code class="computeroutput"><span class="identifier">Sets</span><span class="special">,</span> | |
304 | <span class="identifier">Maps</span></code> | |
305 | </p> | |
306 | </td> | |
307 | <td> | |
308 | <p> | |
309 | <code class="computeroutput"><span class="keyword">template</span></code> | |
310 | </p> | |
311 | </td> | |
312 | <td> | |
313 | <p> | |
314 | <code class="computeroutput"><span class="identifier">Alloc</span></code> | |
315 | </p> | |
316 | </td> | |
317 | <td> | |
318 | <p> | |
319 | <code class="computeroutput"><span class="identifier">Alloc</span><span class="special"><</span></code><span class="emphasis"><em>various</em></span><code class="computeroutput"><span class="special">></span></code> | |
320 | </p> | |
321 | </td> | |
322 | <td> | |
323 | <p> | |
324 | An allocator can be chosen for memory allocation. | |
325 | </p> | |
326 | </td> | |
327 | </tr> | |
328 | </tbody> | |
329 | </table></div> | |
330 | <a name="boost_icl.interface.required_concepts.requirements_on_domaint"></a><h5> | |
331 | <a name="id1107523"></a> | |
332 | <a class="link" href="required_concepts.html#boost_icl.interface.required_concepts.requirements_on_domaint">Requirements | |
333 | on DomainT</a> | |
334 | </h5> | |
335 | <p> | |
336 | The next table gives an overview over the requirements for template parameter | |
337 | <code class="computeroutput"><span class="identifier">DomainT</span></code>. Some requirements | |
338 | are dependent on <span class="emphasis"><em>conditions</em></span>. Column <span class="emphasis"><em>operators</em></span> | |
339 | shows the operators and functions that are expected for <code class="computeroutput"><span class="identifier">DomainT</span></code>, | |
340 | if the default order <code class="computeroutput"><span class="identifier">Compare</span> <span class="special">=</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">less</span></code> is used. | |
341 | </p> | |
342 | <div class="informaltable"><table class="table"> | |
343 | <colgroup> | |
344 | <col> | |
345 | <col> | |
346 | <col> | |
347 | <col> | |
348 | </colgroup> | |
349 | <thead><tr> | |
350 | <th> | |
351 | <p> | |
352 | Parameter | |
353 | </p> | |
354 | </th> | |
355 | <th> | |
356 | <p> | |
357 | Condition | |
358 | </p> | |
359 | </th> | |
360 | <th> | |
361 | <p> | |
362 | Operators | |
363 | </p> | |
364 | </th> | |
365 | <th> | |
366 | <p> | |
367 | Requirement | |
368 | </p> | |
369 | </th> | |
370 | </tr></thead> | |
371 | <tbody> | |
372 | <tr> | |
373 | <td> | |
374 | <p> | |
375 | <code class="computeroutput"><span class="identifier">DomainT</span></code> | |
376 | </p> | |
377 | </td> | |
378 | <td> | |
379 | <p> | |
380 | </p> | |
381 | </td> | |
382 | <td> | |
383 | <p> | |
384 | <code class="computeroutput"><span class="identifier">DomainT</span><span class="special">(),</span> | |
385 | <span class="special"><</span></code> | |
386 | </p> | |
387 | </td> | |
388 | <td> | |
389 | <p> | |
390 | <code class="computeroutput"><span class="identifier">Regular</span><span class="special"><</span><span class="identifier">DomainT</span><span class="special">></span> | |
391 | <span class="special">&&</span> <span class="identifier">StrictWeakOrdering</span><span class="special"><</span><span class="identifier">DomainT</span><span class="special">,</span><span class="identifier">Compare</span><span class="special">></span></code> | |
392 | </p> | |
393 | </td> | |
394 | </tr> | |
395 | <tr> | |
396 | <td> | |
397 | <p> | |
398 | </p> | |
399 | </td> | |
400 | <td> | |
401 | <p> | |
402 | </p> | |
403 | </td> | |
404 | <td> | |
405 | <p> | |
406 | <code class="computeroutput"><span class="special">++,</span> <span class="identifier">unit_element</span><span class="special"><</span><span class="identifier">CodomainT</span><span class="special">>::</span><span class="identifier">value</span><span class="special">()</span></code> | |
407 | </p> | |
408 | </td> | |
409 | <td> | |
410 | <p> | |
411 | <code class="computeroutput"><span class="special">&&</span> <span class="special">(</span><span class="identifier">IsIncrementable</span><span class="special"><</span><span class="identifier">DomainT</span><span class="special">>||</span><span class="identifier">HasUnitElement</span><span class="special"><</span><span class="identifier">DomainT</span><span class="special">>)</span></code> | |
412 | </p> | |
413 | </td> | |
414 | </tr> | |
415 | <tr> | |
416 | <td> | |
417 | <p> | |
418 | </p> | |
419 | </td> | |
420 | <td> | |
421 | <p> | |
422 | <code class="computeroutput"><span class="identifier">IsIntegral</span><span class="special"><</span><span class="identifier">DomainT</span><span class="special">></span></code> | |
423 | </p> | |
424 | </td> | |
425 | <td> | |
426 | <p> | |
427 | <code class="computeroutput"><span class="special">++,</span> <span class="special">--</span></code> | |
428 | </p> | |
429 | </td> | |
430 | <td> | |
431 | <p> | |
432 | <code class="computeroutput"><span class="identifier">IsIncrementable</span><span class="special"><</span><span class="identifier">DomainT</span><span class="special">></span> | |
433 | <span class="special">&&</span> <span class="identifier">IsDecrementable</span><span class="special"><</span><span class="identifier">DomainT</span><span class="special">></span></code> | |
434 | </p> | |
435 | </td> | |
436 | </tr> | |
437 | </tbody> | |
438 | </table></div> | |
439 | <p> | |
440 | A domain type <code class="computeroutput"><span class="identifier">DomainT</span></code> for | |
441 | intervals and interval containers has to satisfy the requirements of concept | |
442 | <a href="http://www.informit.com/guides/content.aspx?g=cplusplus&seqNum=314" target="_top"><code class="computeroutput"><span class="identifier">Regular</span></code></a> which implies among other | |
443 | properties the existence of a copy and a default constructor. In addition | |
444 | <code class="computeroutput"><span class="identifier">IsIncrementable</span></code> <span class="bold"><strong>or</strong></span> <code class="computeroutput"><span class="identifier">HasUnitElement</span></code> | |
445 | is required for <code class="computeroutput"><span class="identifier">DomainT</span></code>. | |
446 | In the <span class="bold"><strong>icl</strong></span> we represent an empty closed | |
447 | interval as interval <code class="computeroutput"><span class="special">[</span><span class="identifier">b</span><span class="special">,</span><span class="identifier">a</span><span class="special">]</span></code> | |
448 | where <code class="computeroutput"><span class="identifier">a</span> <span class="special"><</span> | |
449 | <span class="identifier">b</span></code> (here <code class="computeroutput"><span class="special"><</span></code> | |
450 | represents <code class="computeroutput"><span class="identifier">Compare</span><span class="special"><</span><span class="identifier">DomainT</span><span class="special">>()</span></code>). | |
451 | To construct one of these empty intervals as default constructor for any | |
452 | type <code class="computeroutput"><span class="identifier">DomainT</span></code> we choose <code class="computeroutput"><span class="special">[</span><span class="number">1</span><span class="special">,</span><span class="number">0</span><span class="special">]</span></code>, where | |
453 | <code class="computeroutput"><span class="number">0</span></code> is a null-value or <code class="computeroutput"><span class="identifier">identity_element</span></code> and <code class="computeroutput"><span class="number">1</span></code> | |
454 | is a one-value or <code class="computeroutput"><span class="identifier">unit_element</span></code>: | |
455 | ||
456 | </p> | |
457 | <pre class="programlisting"><span class="identifier">interval</span><span class="special">()</span> <span class="special">:=</span> <span class="special">[</span><span class="identifier">unit_element</span><span class="special"><</span><span class="identifier">DomainT</span><span class="special">>::</span><span class="identifier">value</span><span class="special">(),</span> <span class="identifier">identity_element</span><span class="special"><</span><span class="identifier">DomainT</span><span class="special">>::</span><span class="identifier">value</span><span class="special">()]</span> <span class="comment">//pseudocode | |
458 | </span></pre> | |
459 | <p> | |
460 | <code class="computeroutput"><span class="identifier">Identity_elements</span></code> are implemented | |
461 | via call of the default constructor of <code class="computeroutput"><span class="identifier">DomainT</span></code>. | |
462 | A <code class="computeroutput"><span class="identifier">unit_element</span><span class="special"><</span><span class="identifier">T</span><span class="special">>::</span><span class="identifier">value</span><span class="special">()</span></code> | |
463 | is implemented <code class="computeroutput">by default</code> | |
464 | as a <code class="computeroutput"><span class="identifier">identity_element</span></code>, that | |
465 | is incremented once. | |
466 | </p> | |
467 | <pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">Type</span><span class="special">></span> | |
468 | <span class="keyword">inline</span> <span class="identifier">Type</span> <span class="identifier">unit_element</span><span class="special"><</span><span class="identifier">Type</span><span class="special">>::</span><span class="identifier">value</span><span class="special">(){</span> <span class="keyword">return</span> <span class="identifier">succ</span><span class="special">(</span><span class="identifier">identity_element</span><span class="special"><</span><span class="identifier">Type</span><span class="special">>::</span><span class="identifier">value</span><span class="special">());</span> <span class="special">};</span> | |
469 | </pre> | |
470 | <p> | |
471 | So a type <code class="computeroutput"><span class="identifier">DomainT</span></code> that is | |
472 | <code class="computeroutput"><span class="identifier">incrementable</span></code> will also have | |
473 | an <code class="computeroutput"><span class="identifier">unit_element</span></code>. If it does | |
474 | not, a <code class="computeroutput"><span class="identifier">unit_element</span></code> can be | |
475 | provided. A <code class="computeroutput"><span class="identifier">unit_element</span></code> | |
476 | can be any value, that is greater as the <code class="computeroutput"><span class="identifier">identity_element</span></code> | |
477 | in the <code class="computeroutput"><span class="identifier">Compare</span></code> order given. | |
478 | An example of a type, that has an <code class="computeroutput"><span class="identifier">identity_element</span></code> | |
479 | but no increment operation is <code class="computeroutput"><span class="identifier">string</span></code>. | |
480 | So for <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code> a unit_element is implemented like | |
481 | this: | |
482 | </p> | |
483 | <pre class="programlisting"><span class="comment">// Smallest 'visible' string that is greater than the empty string. | |
484 | </span><span class="keyword">template</span> <span class="special"><></span> | |
485 | <span class="keyword">inline</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">unit_element</span><span class="special"><</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">>::</span><span class="identifier">value</span><span class="special">(){</span> <span class="keyword">return</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">(</span><span class="string">" "</span><span class="special">);</span> <span class="special">};</span> | |
486 | </pre> | |
487 | <p> | |
488 | </p> | |
489 | <p> | |
490 | Just as for the key type of std::sets and maps template parameter <code class="computeroutput"><span class="identifier">Compare</span></code> is required to be a <a href="http://en.wikipedia.org/wiki/Strict_weak_ordering" target="_top">strict | |
491 | weak ordering</a> on <code class="computeroutput"><span class="identifier">DomainT</span></code>. | |
492 | </p> | |
493 | <p> | |
494 | Finally, if <code class="computeroutput"><span class="identifier">DomainT</span></code> is an | |
495 | integral type, <code class="computeroutput"><span class="identifier">DomainT</span></code> needs | |
496 | to be <code class="computeroutput"><span class="identifier">incrementable</span></code> and | |
497 | <code class="computeroutput"><span class="identifier">decrementable</span></code>. This <span class="emphasis"><em>'bicrementability'</em></span> | |
498 | needs to be implemented on the smallest possible unit of the integral type. | |
499 | This seems like being trivial but there are types like e.g. <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">date_time</span><span class="special">::</span><span class="identifier">ptime</span></code>, that are integral in nature but | |
500 | do not provide the required in- and decrementation on the least incrementable | |
501 | unit. For <code class="computeroutput"><a class="link" href="../../boost/icl/interval.html" title="Struct template interval">icl::intervals</a></code> | |
502 | incementation and decementation is used for computations between open to | |
503 | closed interval borders like e.g. <code class="computeroutput"><span class="special">[</span><span class="number">2</span><span class="special">,</span><span class="number">43</span><span class="special">)</span> <span class="special">==</span> <span class="special">[</span><span class="number">2</span><span class="special">,</span><span class="number">42</span><span class="special">]</span></code>. Such computations always need only one | |
504 | in- or decrementation, if <code class="computeroutput"><span class="identifier">DomainT</span></code> | |
505 | is an integral type. | |
506 | </p> | |
507 | <a name="boost_icl.interface.required_concepts.requirements_on_intervalt"></a><h6> | |
508 | <a name="id1108639"></a> | |
509 | <a class="link" href="required_concepts.html#boost_icl.interface.required_concepts.requirements_on_intervalt">Requirements | |
510 | on IntervalT</a> | |
511 | </h6> | |
512 | <p> | |
513 | Requirements on the <code class="computeroutput"><span class="identifier">IntervalT</span></code> | |
514 | parameter are closely related to the <code class="computeroutput"><span class="identifier">DomainT</span></code> | |
515 | parameter. <code class="computeroutput"><span class="identifier">IntervalT</span></code> has | |
516 | two associated types itself for an element type and a compare order that | |
517 | have to be consistent with the element and order parameters of their interval | |
518 | containers. <code class="computeroutput"><span class="identifier">IntervalT</span></code> then | |
519 | has to implement an order called <code class="computeroutput"><span class="identifier">exclusive_less</span></code>. | |
520 | Two intervals <code class="computeroutput"><span class="identifier">x</span><span class="special">,</span> | |
521 | <span class="identifier">y</span></code> are exclusive_less | |
522 | </p> | |
523 | <pre class="programlisting"><span class="identifier">icl</span><span class="special">::</span><span class="identifier">exclusive_less</span><span class="special">(</span><span class="identifier">x</span><span class="special">,</span> <span class="identifier">y</span><span class="special">)</span></pre> | |
524 | <p> | |
525 | if all <code class="computeroutput"><span class="identifier">DomainT</span></code> elements of | |
526 | <code class="computeroutput"><span class="identifier">x</span></code> are less than elements | |
527 | of <code class="computeroutput"><span class="identifier">y</span></code> in the <code class="computeroutput"><span class="identifier">Compare</span></code> order. | |
528 | </p> | |
529 | <div class="informaltable"><table class="table"> | |
530 | <colgroup> | |
531 | <col> | |
532 | <col> | |
533 | <col> | |
534 | </colgroup> | |
535 | <thead><tr> | |
536 | <th> | |
537 | <p> | |
538 | Parameter | |
539 | </p> | |
540 | </th> | |
541 | <th> | |
542 | <p> | |
543 | Operators | |
544 | </p> | |
545 | </th> | |
546 | <th> | |
547 | <p> | |
548 | Requirement | |
549 | </p> | |
550 | </th> | |
551 | </tr></thead> | |
552 | <tbody><tr> | |
553 | <td> | |
554 | <p> | |
555 | <code class="computeroutput"><span class="identifier">IntervalT</span></code> | |
556 | </p> | |
557 | </td> | |
558 | <td> | |
559 | <p> | |
560 | <code class="computeroutput"><span class="identifier">exclusive_less</span></code> | |
561 | </p> | |
562 | </td> | |
563 | <td> | |
564 | <p> | |
565 | <code class="computeroutput"><span class="identifier">IsExclusiveLessComparable</span><span class="special"><</span><span class="identifier">Interval</span><span class="special"><</span><span class="identifier">DomainT</span><span class="special">,</span><span class="identifier">Compare</span><span class="special">></span> <span class="special">></span></code> | |
566 | </p> | |
567 | </td> | |
568 | </tr></tbody> | |
569 | </table></div> | |
570 | <a name="boost_icl.interface.required_concepts.requirements_on_codomaint"></a><h5> | |
571 | <a name="id1108888"></a> | |
572 | <a class="link" href="required_concepts.html#boost_icl.interface.required_concepts.requirements_on_codomaint">Requirements | |
573 | on CodomainT</a> | |
574 | </h5> | |
575 | <p> | |
576 | Summarized in the next table are requirements for template parameter <code class="computeroutput"><span class="identifier">CodomainT</span></code> of associated values for <code class="computeroutput"><span class="identifier">Maps</span></code>. Again there are <span class="emphasis"><em>conditions</em></span> | |
577 | for some of the requirements. Column <span class="emphasis"><em>operators</em></span> contains | |
578 | the operators and functions required for <code class="computeroutput"><span class="identifier">CodomainT</span></code>, | |
579 | if we are using the default combiner <code class="computeroutput"><span class="identifier">Combine</span> | |
580 | <span class="special">=</span> <span class="identifier">icl</span><span class="special">::</span><span class="identifier">inplace_plus</span></code>. | |
581 | </p> | |
582 | <div class="informaltable"><table class="table"> | |
583 | <colgroup> | |
584 | <col> | |
585 | <col> | |
586 | <col> | |
587 | <col> | |
588 | </colgroup> | |
589 | <thead><tr> | |
590 | <th> | |
591 | <p> | |
592 | Parameter | |
593 | </p> | |
594 | </th> | |
595 | <th> | |
596 | <p> | |
597 | Condition | |
598 | </p> | |
599 | </th> | |
600 | <th> | |
601 | <p> | |
602 | Operators | |
603 | </p> | |
604 | </th> | |
605 | <th> | |
606 | <p> | |
607 | Requirement | |
608 | </p> | |
609 | </th> | |
610 | </tr></thead> | |
611 | <tbody> | |
612 | <tr> | |
613 | <td> | |
614 | <p> | |
615 | <code class="computeroutput"><span class="identifier">CodomainT</span></code> | |
616 | </p> | |
617 | </td> | |
618 | <td> | |
619 | <p> | |
620 | <code class="computeroutput"><span class="identifier">add</span></code>, <code class="computeroutput"><span class="identifier">subtract</span></code>, <code class="computeroutput"><span class="identifier">intersect</span></code> | |
621 | unused | |
622 | </p> | |
623 | </td> | |
624 | <td> | |
625 | <p> | |
626 | <code class="computeroutput"><span class="identifier">CodomainT</span><span class="special">(),</span> | |
627 | <span class="special">==</span></code> | |
628 | </p> | |
629 | </td> | |
630 | <td> | |
631 | <p> | |
632 | <code class="computeroutput"><span class="identifier">Regular</span><span class="special"><</span><span class="identifier">CodomainT</span><span class="special">></span></code> | |
633 | which implies | |
634 | </p> | |
635 | </td> | |
636 | </tr> | |
637 | <tr> | |
638 | <td> | |
639 | <p> | |
640 | </p> | |
641 | </td> | |
642 | <td> | |
643 | <p> | |
644 | </p> | |
645 | </td> | |
646 | <td> | |
647 | <p> | |
648 | </p> | |
649 | </td> | |
650 | <td> | |
651 | <p> | |
652 | <code class="computeroutput"><span class="identifier">DefaultConstructible</span><span class="special"><</span><span class="identifier">CodomainT</span><span class="special">></span> <span class="special">&&</span> | |
653 | <span class="identifier">EqualityComparable</span><span class="special"><</span><span class="identifier">CodomainT</span><span class="special">></span></code> | |
654 | </p> | |
655 | </td> | |
656 | </tr> | |
657 | <tr> | |
658 | <td> | |
659 | <p> | |
660 | </p> | |
661 | </td> | |
662 | <td> | |
663 | <p> | |
664 | only <code class="computeroutput"><span class="identifier">add</span></code> used | |
665 | </p> | |
666 | </td> | |
667 | <td> | |
668 | <p> | |
669 | <code class="computeroutput"><span class="special">+=</span></code> | |
670 | </p> | |
671 | </td> | |
672 | <td> | |
673 | <p> | |
674 | <code class="computeroutput"><span class="special">&&</span> <span class="identifier">Combinable</span><span class="special"><</span><span class="identifier">CodomainT</span><span class="special">,</span><span class="identifier">Combine</span><span class="special">></span></code> | |
675 | </p> | |
676 | </td> | |
677 | </tr> | |
678 | <tr> | |
679 | <td> | |
680 | <p> | |
681 | </p> | |
682 | </td> | |
683 | <td> | |
684 | <p> | |
685 | ... and also <code class="computeroutput"><span class="identifier">subtract</span></code> | |
686 | used | |
687 | </p> | |
688 | </td> | |
689 | <td> | |
690 | <p> | |
691 | <code class="computeroutput"><span class="special">-=</span></code> | |
692 | </p> | |
693 | </td> | |
694 | <td> | |
695 | <p> | |
696 | <code class="computeroutput"><span class="special">&&</span> <span class="identifier">Combinable</span><span class="special"><</span><span class="identifier">CodomainT</span><span class="special">,</span><span class="identifier">Inverse</span><span class="special"><</span><span class="identifier">Combine</span><span class="special">></span> <span class="special">></span></code> | |
697 | </p> | |
698 | </td> | |
699 | </tr> | |
700 | <tr> | |
701 | <td> | |
702 | <p> | |
703 | </p> | |
704 | </td> | |
705 | <td> | |
706 | <p> | |
707 | <code class="computeroutput"><span class="identifier">Section</span></code> used and | |
708 | <code class="computeroutput"><span class="identifier">CodomainT</span></code> is a set | |
709 | </p> | |
710 | </td> | |
711 | <td> | |
712 | <p> | |
713 | <code class="computeroutput"><span class="special">&=</span></code> | |
714 | </p> | |
715 | </td> | |
716 | <td> | |
717 | <p> | |
718 | <code class="computeroutput"><span class="special">&&</span> <span class="identifier">Intersectable</span><span class="special"><</span><span class="identifier">CodomainT</span><span class="special">,</span><span class="identifier">Section</span><span class="special">></span></code> | |
719 | </p> | |
720 | </td> | |
721 | </tr> | |
722 | </tbody> | |
723 | </table></div> | |
724 | <p> | |
725 | The requirements on the type <code class="computeroutput"><span class="identifier">CodomainT</span></code> | |
726 | of associated values for a <code class="computeroutput"><a class="link" href="../../boost/icl/map.html" title="Class template map">icl::map</a></code> | |
727 | or <code class="computeroutput"><a class="link" href="../../boost/icl/interval_map.html" title="Class template interval_map">interval_map</a></code> depend | |
728 | on the usage of their aggregation functionality. If aggregation on overlap | |
729 | is never used, that is to say that none of the addition, subtraction and | |
730 | intersection operations (<code class="computeroutput"><span class="special">+,</span> <span class="special">+=,</span> <span class="identifier">add</span></code>, | |
731 | <code class="computeroutput"><span class="special">-,</span> <span class="special">-=,</span> | |
732 | <span class="identifier">subtract</span></code>, &, &=, add_intersection) | |
733 | are used on the <code class="computeroutput"><a class="link" href="../../boost/icl/interval_map.html" title="Class template interval_map">interval_map</a></code>, | |
734 | then <code class="computeroutput"><span class="identifier">CodomainT</span></code> only needs | |
735 | to be <a href="http://www.informit.com/guides/content.aspx?g=cplusplus&seqNum=314" target="_top">Regular</a>. | |
736 | </p> | |
737 | <p> | |
738 | <span class="emphasis"><em><span class="bold"><strong>Regular</strong></span></em></span> object semantics | |
739 | implies <code class="computeroutput"><span class="identifier">DefaultConstructible</span></code> | |
740 | and <code class="computeroutput"><span class="identifier">EqualityComparable</span></code> which | |
741 | means it has a default ctor <code class="computeroutput"><span class="identifier">CodomainT</span><span class="special">()</span></code> and an <code class="computeroutput"><span class="keyword">operator</span> | |
742 | <span class="special">==</span></code>. | |
743 | </p> | |
744 | <p> | |
745 | Use <code class="computeroutput"><a class="link" href="../../boost/icl/interval_map.html" title="Class template interval_map">interval_maps</a></code> | |
746 | <span class="emphasis"><em><span class="bold"><strong>without aggregation</strong></span></em></span>, | |
747 | if the associated values are not addable but still are attached to intervals | |
748 | so you want to use <code class="computeroutput"><a class="link" href="../../boost/icl/interval_map.html" title="Class template interval_map">interval_maps</a></code> | |
749 | to handle them. As long as those values are added with <code class="computeroutput"><span class="identifier">insert</span></code> | |
750 | and deleted with <code class="computeroutput"><span class="identifier">erase</span></code> <code class="computeroutput"><a class="link" href="../../boost/icl/interval_map.html" title="Class template interval_map">interval_maps</a></code> will work fine with | |
751 | such values. | |
752 | </p> | |
753 | <p> | |
754 | If <span class="emphasis"><em><span class="bold"><strong>only addition</strong></span></em></span> is | |
755 | used via <code class="computeroutput"><a class="link" href="../../boost/icl/interval_map.html" title="Class template interval_map">interval_map's</a></code> | |
756 | <code class="computeroutput"><span class="special">+,</span> <span class="special">+=</span></code> | |
757 | or <code class="computeroutput"><span class="identifier">add</span></code> but no subtraction, | |
758 | then <code class="computeroutput"><span class="identifier">CodomainT</span></code> need to be | |
759 | <code class="computeroutput"><span class="identifier">Combinable</span></code> for functor template | |
760 | <code class="computeroutput"><span class="identifier">Combine</span></code>. That means in most | |
761 | cases when the default implementation <code class="computeroutput"><span class="identifier">inplace_plus</span></code> | |
762 | for <code class="computeroutput"><span class="identifier">Combine</span></code> is used, that | |
763 | <code class="computeroutput"><span class="identifier">CodomainT</span></code> has to implement | |
764 | <code class="computeroutput"><span class="keyword">operator</span> <span class="special">+=</span></code>. | |
765 | </p> | |
766 | <p> | |
767 | For associated value types, that are addable but not subtractable like e.g. | |
768 | <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code> it usually makes sense to use addition | |
769 | to combine values but the inverse combination is not desired. | |
770 | </p> | |
771 | <pre class="programlisting"><span class="identifier">interval_map</span><span class="special"><</span><span class="keyword">int</span><span class="special">,</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">></span> <span class="identifier">cat_map</span><span class="special">;</span> | |
772 | <span class="identifier">cat_map</span> <span class="special">+=</span> <span class="identifier">make_pair</span><span class="special">(</span><span class="identifier">interval</span><span class="special"><</span><span class="keyword">int</span><span class="special">>::</span><span class="identifier">rightopen</span><span class="special">(</span><span class="number">1</span><span class="special">,</span><span class="number">5</span><span class="special">),</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">(</span><span class="string">"Hello"</span><span class="special">));</span> | |
773 | <span class="identifier">cat_map</span> <span class="special">+=</span> <span class="identifier">make_pair</span><span class="special">(</span><span class="identifier">interval</span><span class="special"><</span><span class="keyword">int</span><span class="special">>::</span><span class="identifier">rightopen</span><span class="special">(</span><span class="number">3</span><span class="special">,</span><span class="number">7</span><span class="special">),</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">(</span><span class="string">" world"</span><span class="special">));</span> | |
774 | <span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"cat_map: "</span> <span class="special"><<</span> <span class="identifier">cat_map</span> <span class="special"><<</span> <span class="identifier">endl</span><span class="special">;</span> | |
775 | <span class="comment">//cat_map: {([1,3)->Hello)([3,5)->Hello world)([5,7)-> world)} | |
776 | </span></pre> | |
777 | <p> | |
778 | </p> | |
779 | <p> | |
780 | For <span class="emphasis"><em>complete aggregation functionality</em></span> an inverse aggregation | |
781 | functor on a <code class="computeroutput"><span class="identifier">Map</span></code>'s <code class="computeroutput"><span class="identifier">CodomainT</span></code> is needed. The icl provides a | |
782 | metafunction <code class="computeroutput"><a class="link" href="../../boost/icl/inverse.html" title="Struct template inverse">inverse</a></code> for | |
783 | that purpose. Using the default <code class="computeroutput"><span class="identifier">Combine</span> | |
784 | <span class="special">=</span> <span class="identifier">inplace_plus</span></code> | |
785 | that relies on the existence of <code class="computeroutput"><span class="keyword">operator</span> | |
786 | <span class="special">+=</span></code> on type <code class="computeroutput"><span class="identifier">CodomainT</span></code> | |
787 | metafunction <code class="computeroutput"><a class="link" href="../../boost/icl/inverse.html" title="Struct template inverse">inverse</a></code> will | |
788 | infer <code class="computeroutput"><a class="link" href="../../boost/icl/inplace_minus.html" title="Struct template inplace_minus">inplace_minus</a></code> | |
789 | as inverse functor, that requires <code class="computeroutput"><span class="keyword">operator</span> | |
790 | <span class="special">-=</span></code> on type <code class="computeroutput"><span class="identifier">CodomainT</span></code>. | |
791 | </p> | |
792 | <p> | |
793 | In the icl's design we make the assumption, in particular for the default | |
794 | setting of parameters <code class="computeroutput"><span class="identifier">Combine</span> <span class="special">=</span> </code><code class="computeroutput"><a class="link" href="../../boost/icl/inplace_minus.html" title="Struct template inplace_minus">inplace_plus</a></code>, | |
795 | that type <code class="computeroutput"><span class="identifier">CodomainT</span></code> has a | |
796 | neutral element or <code class="computeroutput"><span class="identifier">identity_element</span></code> | |
797 | with respect to the <code class="computeroutput"><span class="identifier">Combine</span></code> | |
798 | functor. | |
799 | </p> | |
800 | </div> | |
801 | <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> | |
802 | <td align="left"></td> | |
803 | <td align="right"><div class="copyright-footer">Copyright © 2007 -2010 Joachim Faulhaber<br>Copyright © 1999 -2006 Cortex Software GmbH<p> | |
804 | Distributed under the Boost Software License, Version 1.0. (See accompanying | |
805 | file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) | |
806 | </p> | |
807 | </div></td> | |
808 | </tr></table> | |
809 | <hr> | |
810 | <div class="spirit-nav"> | |
811 | <a accesskey="p" href="../interface.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../interface.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="associated_types.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> | |
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