1 | // (C) Copyright Steve Cleary, Beman Dawes, Howard Hinnant & John Maddock 2000. |
---|
2 | // Use, modification and distribution are subject to the Boost Software License, |
---|
3 | // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
---|
4 | // http://www.boost.org/LICENSE_1_0.txt). |
---|
5 | // |
---|
6 | // See http://www.boost.org/libs/utility for most recent version including documentation. |
---|
7 | // see libs/utility/compressed_pair.hpp |
---|
8 | // |
---|
9 | /* Release notes: |
---|
10 | 20 Jan 2001: |
---|
11 | Fixed obvious bugs (David Abrahams) |
---|
12 | 07 Oct 2000: |
---|
13 | Added better single argument constructor support. |
---|
14 | 03 Oct 2000: |
---|
15 | Added VC6 support (JM). |
---|
16 | 23rd July 2000: |
---|
17 | Additional comments added. (JM) |
---|
18 | Jan 2000: |
---|
19 | Original version: this version crippled for use with crippled compilers |
---|
20 | - John Maddock Jan 2000. |
---|
21 | */ |
---|
22 | |
---|
23 | |
---|
24 | #ifndef BOOST_OB_COMPRESSED_PAIR_HPP |
---|
25 | #define BOOST_OB_COMPRESSED_PAIR_HPP |
---|
26 | |
---|
27 | #include <algorithm> |
---|
28 | #ifndef BOOST_OBJECT_TYPE_TRAITS_HPP |
---|
29 | #include <boost/type_traits/object_traits.hpp> |
---|
30 | #endif |
---|
31 | #ifndef BOOST_SAME_TRAITS_HPP |
---|
32 | #include <boost/type_traits/same_traits.hpp> |
---|
33 | #endif |
---|
34 | #ifndef BOOST_CALL_TRAITS_HPP |
---|
35 | #include <boost/call_traits.hpp> |
---|
36 | #endif |
---|
37 | |
---|
38 | namespace boost |
---|
39 | { |
---|
40 | #ifdef BOOST_MSVC6_MEMBER_TEMPLATES |
---|
41 | // |
---|
42 | // use member templates to emulate |
---|
43 | // partial specialisation. Note that due to |
---|
44 | // problems with overload resolution with VC6 |
---|
45 | // each of the compressed_pair versions that follow |
---|
46 | // have one template single-argument constructor |
---|
47 | // in place of two specific constructors: |
---|
48 | // |
---|
49 | |
---|
50 | template <class T1, class T2> |
---|
51 | class compressed_pair; |
---|
52 | |
---|
53 | namespace detail{ |
---|
54 | |
---|
55 | template <class A, class T1, class T2> |
---|
56 | struct best_conversion_traits |
---|
57 | { |
---|
58 | typedef char one; |
---|
59 | typedef char (&two)[2]; |
---|
60 | static A a; |
---|
61 | static one test(T1); |
---|
62 | static two test(T2); |
---|
63 | |
---|
64 | enum { value = sizeof(test(a)) }; |
---|
65 | }; |
---|
66 | |
---|
67 | template <int> |
---|
68 | struct init_one; |
---|
69 | |
---|
70 | template <> |
---|
71 | struct init_one<1> |
---|
72 | { |
---|
73 | template <class A, class T1, class T2> |
---|
74 | static void init(const A& a, T1* p1, T2*) |
---|
75 | { |
---|
76 | *p1 = a; |
---|
77 | } |
---|
78 | }; |
---|
79 | |
---|
80 | template <> |
---|
81 | struct init_one<2> |
---|
82 | { |
---|
83 | template <class A, class T1, class T2> |
---|
84 | static void init(const A& a, T1*, T2* p2) |
---|
85 | { |
---|
86 | *p2 = a; |
---|
87 | } |
---|
88 | }; |
---|
89 | |
---|
90 | |
---|
91 | // T1 != T2, both non-empty |
---|
92 | template <class T1, class T2> |
---|
93 | class compressed_pair_0 |
---|
94 | { |
---|
95 | private: |
---|
96 | T1 _first; |
---|
97 | T2 _second; |
---|
98 | public: |
---|
99 | typedef T1 first_type; |
---|
100 | typedef T2 second_type; |
---|
101 | typedef typename call_traits<first_type>::param_type first_param_type; |
---|
102 | typedef typename call_traits<second_type>::param_type second_param_type; |
---|
103 | typedef typename call_traits<first_type>::reference first_reference; |
---|
104 | typedef typename call_traits<second_type>::reference second_reference; |
---|
105 | typedef typename call_traits<first_type>::const_reference first_const_reference; |
---|
106 | typedef typename call_traits<second_type>::const_reference second_const_reference; |
---|
107 | |
---|
108 | compressed_pair_0() : _first(), _second() {} |
---|
109 | compressed_pair_0(first_param_type x, second_param_type y) : _first(x), _second(y) {} |
---|
110 | template <class A> |
---|
111 | explicit compressed_pair_0(const A& val) |
---|
112 | { |
---|
113 | init_one<best_conversion_traits<A, T1, T2>::value>::init(val, &_first, &_second); |
---|
114 | } |
---|
115 | compressed_pair_0(const ::boost::compressed_pair<T1,T2>& x) |
---|
116 | : _first(x.first()), _second(x.second()) {} |
---|
117 | |
---|
118 | #if 0 |
---|
119 | compressed_pair_0& operator=(const compressed_pair_0& x) { |
---|
120 | cout << "assigning compressed pair 0" << endl; |
---|
121 | _first = x._first; |
---|
122 | _second = x._second; |
---|
123 | cout << "finished assigning compressed pair 0" << endl; |
---|
124 | return *this; |
---|
125 | } |
---|
126 | #endif |
---|
127 | |
---|
128 | first_reference first() { return _first; } |
---|
129 | first_const_reference first() const { return _first; } |
---|
130 | |
---|
131 | second_reference second() { return _second; } |
---|
132 | second_const_reference second() const { return _second; } |
---|
133 | |
---|
134 | void swap(compressed_pair_0& y) |
---|
135 | { |
---|
136 | using std::swap; |
---|
137 | swap(_first, y._first); |
---|
138 | swap(_second, y._second); |
---|
139 | } |
---|
140 | }; |
---|
141 | |
---|
142 | // T1 != T2, T2 empty |
---|
143 | template <class T1, class T2> |
---|
144 | class compressed_pair_1 : T2 |
---|
145 | { |
---|
146 | private: |
---|
147 | T1 _first; |
---|
148 | public: |
---|
149 | typedef T1 first_type; |
---|
150 | typedef T2 second_type; |
---|
151 | typedef typename call_traits<first_type>::param_type first_param_type; |
---|
152 | typedef typename call_traits<second_type>::param_type second_param_type; |
---|
153 | typedef typename call_traits<first_type>::reference first_reference; |
---|
154 | typedef typename call_traits<second_type>::reference second_reference; |
---|
155 | typedef typename call_traits<first_type>::const_reference first_const_reference; |
---|
156 | typedef typename call_traits<second_type>::const_reference second_const_reference; |
---|
157 | |
---|
158 | compressed_pair_1() : T2(), _first() {} |
---|
159 | compressed_pair_1(first_param_type x, second_param_type y) : T2(y), _first(x) {} |
---|
160 | |
---|
161 | template <class A> |
---|
162 | explicit compressed_pair_1(const A& val) |
---|
163 | { |
---|
164 | init_one<best_conversion_traits<A, T1, T2>::value>::init(val, &_first, static_cast<T2*>(this)); |
---|
165 | } |
---|
166 | |
---|
167 | compressed_pair_1(const ::boost::compressed_pair<T1,T2>& x) |
---|
168 | : T2(x.second()), _first(x.first()) {} |
---|
169 | |
---|
170 | #if defined(BOOST_MSVC) && BOOST_MSVC <= 1300 |
---|
171 | // Total weirdness. If the assignment to _first is moved after |
---|
172 | // the call to the inherited operator=, then this breaks graph/test/graph.cpp |
---|
173 | // by way of iterator_adaptor. |
---|
174 | compressed_pair_1& operator=(const compressed_pair_1& x) { |
---|
175 | _first = x._first; |
---|
176 | T2::operator=(x); |
---|
177 | return *this; |
---|
178 | } |
---|
179 | #endif |
---|
180 | |
---|
181 | first_reference first() { return _first; } |
---|
182 | first_const_reference first() const { return _first; } |
---|
183 | |
---|
184 | second_reference second() { return *this; } |
---|
185 | second_const_reference second() const { return *this; } |
---|
186 | |
---|
187 | void swap(compressed_pair_1& y) |
---|
188 | { |
---|
189 | // no need to swap empty base class: |
---|
190 | using std::swap; |
---|
191 | swap(_first, y._first); |
---|
192 | } |
---|
193 | }; |
---|
194 | |
---|
195 | // T1 != T2, T1 empty |
---|
196 | template <class T1, class T2> |
---|
197 | class compressed_pair_2 : T1 |
---|
198 | { |
---|
199 | private: |
---|
200 | T2 _second; |
---|
201 | public: |
---|
202 | typedef T1 first_type; |
---|
203 | typedef T2 second_type; |
---|
204 | typedef typename call_traits<first_type>::param_type first_param_type; |
---|
205 | typedef typename call_traits<second_type>::param_type second_param_type; |
---|
206 | typedef typename call_traits<first_type>::reference first_reference; |
---|
207 | typedef typename call_traits<second_type>::reference second_reference; |
---|
208 | typedef typename call_traits<first_type>::const_reference first_const_reference; |
---|
209 | typedef typename call_traits<second_type>::const_reference second_const_reference; |
---|
210 | |
---|
211 | compressed_pair_2() : T1(), _second() {} |
---|
212 | compressed_pair_2(first_param_type x, second_param_type y) : T1(x), _second(y) {} |
---|
213 | template <class A> |
---|
214 | explicit compressed_pair_2(const A& val) |
---|
215 | { |
---|
216 | init_one<best_conversion_traits<A, T1, T2>::value>::init(val, static_cast<T1*>(this), &_second); |
---|
217 | } |
---|
218 | compressed_pair_2(const ::boost::compressed_pair<T1,T2>& x) |
---|
219 | : T1(x.first()), _second(x.second()) {} |
---|
220 | |
---|
221 | #if 0 |
---|
222 | compressed_pair_2& operator=(const compressed_pair_2& x) { |
---|
223 | cout << "assigning compressed pair 2" << endl; |
---|
224 | T1::operator=(x); |
---|
225 | _second = x._second; |
---|
226 | cout << "finished assigning compressed pair 2" << endl; |
---|
227 | return *this; |
---|
228 | } |
---|
229 | #endif |
---|
230 | first_reference first() { return *this; } |
---|
231 | first_const_reference first() const { return *this; } |
---|
232 | |
---|
233 | second_reference second() { return _second; } |
---|
234 | second_const_reference second() const { return _second; } |
---|
235 | |
---|
236 | void swap(compressed_pair_2& y) |
---|
237 | { |
---|
238 | // no need to swap empty base class: |
---|
239 | using std::swap; |
---|
240 | swap(_second, y._second); |
---|
241 | } |
---|
242 | }; |
---|
243 | |
---|
244 | // T1 != T2, both empty |
---|
245 | template <class T1, class T2> |
---|
246 | class compressed_pair_3 : T1, T2 |
---|
247 | { |
---|
248 | public: |
---|
249 | typedef T1 first_type; |
---|
250 | typedef T2 second_type; |
---|
251 | typedef typename call_traits<first_type>::param_type first_param_type; |
---|
252 | typedef typename call_traits<second_type>::param_type second_param_type; |
---|
253 | typedef typename call_traits<first_type>::reference first_reference; |
---|
254 | typedef typename call_traits<second_type>::reference second_reference; |
---|
255 | typedef typename call_traits<first_type>::const_reference first_const_reference; |
---|
256 | typedef typename call_traits<second_type>::const_reference second_const_reference; |
---|
257 | |
---|
258 | compressed_pair_3() : T1(), T2() {} |
---|
259 | compressed_pair_3(first_param_type x, second_param_type y) : T1(x), T2(y) {} |
---|
260 | template <class A> |
---|
261 | explicit compressed_pair_3(const A& val) |
---|
262 | { |
---|
263 | init_one<best_conversion_traits<A, T1, T2>::value>::init(val, static_cast<T1*>(this), static_cast<T2*>(this)); |
---|
264 | } |
---|
265 | compressed_pair_3(const ::boost::compressed_pair<T1,T2>& x) |
---|
266 | : T1(x.first()), T2(x.second()) {} |
---|
267 | |
---|
268 | first_reference first() { return *this; } |
---|
269 | first_const_reference first() const { return *this; } |
---|
270 | |
---|
271 | second_reference second() { return *this; } |
---|
272 | second_const_reference second() const { return *this; } |
---|
273 | |
---|
274 | void swap(compressed_pair_3& y) |
---|
275 | { |
---|
276 | // no need to swap empty base classes: |
---|
277 | } |
---|
278 | }; |
---|
279 | |
---|
280 | // T1 == T2, and empty |
---|
281 | template <class T1, class T2> |
---|
282 | class compressed_pair_4 : T1 |
---|
283 | { |
---|
284 | public: |
---|
285 | typedef T1 first_type; |
---|
286 | typedef T2 second_type; |
---|
287 | typedef typename call_traits<first_type>::param_type first_param_type; |
---|
288 | typedef typename call_traits<second_type>::param_type second_param_type; |
---|
289 | typedef typename call_traits<first_type>::reference first_reference; |
---|
290 | typedef typename call_traits<second_type>::reference second_reference; |
---|
291 | typedef typename call_traits<first_type>::const_reference first_const_reference; |
---|
292 | typedef typename call_traits<second_type>::const_reference second_const_reference; |
---|
293 | |
---|
294 | compressed_pair_4() : T1() {} |
---|
295 | compressed_pair_4(first_param_type x, second_param_type y) : T1(x), m_second(y) {} |
---|
296 | // only one single argument constructor since T1 == T2 |
---|
297 | explicit compressed_pair_4(first_param_type x) : T1(x), m_second(x) {} |
---|
298 | compressed_pair_4(const ::boost::compressed_pair<T1,T2>& x) |
---|
299 | : T1(x.first()), m_second(x.second()) {} |
---|
300 | |
---|
301 | first_reference first() { return *this; } |
---|
302 | first_const_reference first() const { return *this; } |
---|
303 | |
---|
304 | second_reference second() { return m_second; } |
---|
305 | second_const_reference second() const { return m_second; } |
---|
306 | |
---|
307 | void swap(compressed_pair_4& y) |
---|
308 | { |
---|
309 | // no need to swap empty base classes: |
---|
310 | } |
---|
311 | private: |
---|
312 | T2 m_second; |
---|
313 | }; |
---|
314 | |
---|
315 | // T1 == T2, not empty |
---|
316 | template <class T1, class T2> |
---|
317 | class compressed_pair_5 |
---|
318 | { |
---|
319 | private: |
---|
320 | T1 _first; |
---|
321 | T2 _second; |
---|
322 | public: |
---|
323 | typedef T1 first_type; |
---|
324 | typedef T2 second_type; |
---|
325 | typedef typename call_traits<first_type>::param_type first_param_type; |
---|
326 | typedef typename call_traits<second_type>::param_type second_param_type; |
---|
327 | typedef typename call_traits<first_type>::reference first_reference; |
---|
328 | typedef typename call_traits<second_type>::reference second_reference; |
---|
329 | typedef typename call_traits<first_type>::const_reference first_const_reference; |
---|
330 | typedef typename call_traits<second_type>::const_reference second_const_reference; |
---|
331 | |
---|
332 | compressed_pair_5() : _first(), _second() {} |
---|
333 | compressed_pair_5(first_param_type x, second_param_type y) : _first(x), _second(y) {} |
---|
334 | // only one single argument constructor since T1 == T2 |
---|
335 | explicit compressed_pair_5(first_param_type x) : _first(x), _second(x) {} |
---|
336 | compressed_pair_5(const ::boost::compressed_pair<T1,T2>& c) |
---|
337 | : _first(c.first()), _second(c.second()) {} |
---|
338 | |
---|
339 | first_reference first() { return _first; } |
---|
340 | first_const_reference first() const { return _first; } |
---|
341 | |
---|
342 | second_reference second() { return _second; } |
---|
343 | second_const_reference second() const { return _second; } |
---|
344 | |
---|
345 | void swap(compressed_pair_5& y) |
---|
346 | { |
---|
347 | using std::swap; |
---|
348 | swap(_first, y._first); |
---|
349 | swap(_second, y._second); |
---|
350 | } |
---|
351 | }; |
---|
352 | |
---|
353 | template <bool e1, bool e2, bool same> |
---|
354 | struct compressed_pair_chooser |
---|
355 | { |
---|
356 | template <class T1, class T2> |
---|
357 | struct rebind |
---|
358 | { |
---|
359 | typedef compressed_pair_0<T1, T2> type; |
---|
360 | }; |
---|
361 | }; |
---|
362 | |
---|
363 | template <> |
---|
364 | struct compressed_pair_chooser<false, true, false> |
---|
365 | { |
---|
366 | template <class T1, class T2> |
---|
367 | struct rebind |
---|
368 | { |
---|
369 | typedef compressed_pair_1<T1, T2> type; |
---|
370 | }; |
---|
371 | }; |
---|
372 | |
---|
373 | template <> |
---|
374 | struct compressed_pair_chooser<true, false, false> |
---|
375 | { |
---|
376 | template <class T1, class T2> |
---|
377 | struct rebind |
---|
378 | { |
---|
379 | typedef compressed_pair_2<T1, T2> type; |
---|
380 | }; |
---|
381 | }; |
---|
382 | |
---|
383 | template <> |
---|
384 | struct compressed_pair_chooser<true, true, false> |
---|
385 | { |
---|
386 | template <class T1, class T2> |
---|
387 | struct rebind |
---|
388 | { |
---|
389 | typedef compressed_pair_3<T1, T2> type; |
---|
390 | }; |
---|
391 | }; |
---|
392 | |
---|
393 | template <> |
---|
394 | struct compressed_pair_chooser<true, true, true> |
---|
395 | { |
---|
396 | template <class T1, class T2> |
---|
397 | struct rebind |
---|
398 | { |
---|
399 | typedef compressed_pair_4<T1, T2> type; |
---|
400 | }; |
---|
401 | }; |
---|
402 | |
---|
403 | template <> |
---|
404 | struct compressed_pair_chooser<false, false, true> |
---|
405 | { |
---|
406 | template <class T1, class T2> |
---|
407 | struct rebind |
---|
408 | { |
---|
409 | typedef compressed_pair_5<T1, T2> type; |
---|
410 | }; |
---|
411 | }; |
---|
412 | |
---|
413 | template <class T1, class T2> |
---|
414 | struct compressed_pair_traits |
---|
415 | { |
---|
416 | private: |
---|
417 | typedef compressed_pair_chooser<is_empty<T1>::value, is_empty<T2>::value, is_same<T1,T2>::value> chooser; |
---|
418 | typedef typename chooser::template rebind<T1, T2> bound_type; |
---|
419 | public: |
---|
420 | typedef typename bound_type::type type; |
---|
421 | }; |
---|
422 | |
---|
423 | } // namespace detail |
---|
424 | |
---|
425 | template <class T1, class T2> |
---|
426 | class compressed_pair : public detail::compressed_pair_traits<T1, T2>::type |
---|
427 | { |
---|
428 | private: |
---|
429 | typedef typename detail::compressed_pair_traits<T1, T2>::type base_type; |
---|
430 | public: |
---|
431 | typedef T1 first_type; |
---|
432 | typedef T2 second_type; |
---|
433 | typedef typename call_traits<first_type>::param_type first_param_type; |
---|
434 | typedef typename call_traits<second_type>::param_type second_param_type; |
---|
435 | typedef typename call_traits<first_type>::reference first_reference; |
---|
436 | typedef typename call_traits<second_type>::reference second_reference; |
---|
437 | typedef typename call_traits<first_type>::const_reference first_const_reference; |
---|
438 | typedef typename call_traits<second_type>::const_reference second_const_reference; |
---|
439 | |
---|
440 | compressed_pair() : base_type() {} |
---|
441 | compressed_pair(first_param_type x, second_param_type y) : base_type(x, y) {} |
---|
442 | template <class A> |
---|
443 | explicit compressed_pair(const A& x) : base_type(x){} |
---|
444 | |
---|
445 | first_reference first() { return base_type::first(); } |
---|
446 | first_const_reference first() const { return base_type::first(); } |
---|
447 | |
---|
448 | second_reference second() { return base_type::second(); } |
---|
449 | second_const_reference second() const { return base_type::second(); } |
---|
450 | }; |
---|
451 | |
---|
452 | template <class T1, class T2> |
---|
453 | inline void swap(compressed_pair<T1, T2>& x, compressed_pair<T1, T2>& y) |
---|
454 | { |
---|
455 | x.swap(y); |
---|
456 | } |
---|
457 | |
---|
458 | #else |
---|
459 | // no partial specialisation, no member templates: |
---|
460 | |
---|
461 | template <class T1, class T2> |
---|
462 | class compressed_pair |
---|
463 | { |
---|
464 | private: |
---|
465 | T1 _first; |
---|
466 | T2 _second; |
---|
467 | public: |
---|
468 | typedef T1 first_type; |
---|
469 | typedef T2 second_type; |
---|
470 | typedef typename call_traits<first_type>::param_type first_param_type; |
---|
471 | typedef typename call_traits<second_type>::param_type second_param_type; |
---|
472 | typedef typename call_traits<first_type>::reference first_reference; |
---|
473 | typedef typename call_traits<second_type>::reference second_reference; |
---|
474 | typedef typename call_traits<first_type>::const_reference first_const_reference; |
---|
475 | typedef typename call_traits<second_type>::const_reference second_const_reference; |
---|
476 | |
---|
477 | compressed_pair() : _first(), _second() {} |
---|
478 | compressed_pair(first_param_type x, second_param_type y) : _first(x), _second(y) {} |
---|
479 | explicit compressed_pair(first_param_type x) : _first(x), _second() {} |
---|
480 | // can't define this in case T1 == T2: |
---|
481 | // explicit compressed_pair(second_param_type y) : _first(), _second(y) {} |
---|
482 | |
---|
483 | first_reference first() { return _first; } |
---|
484 | first_const_reference first() const { return _first; } |
---|
485 | |
---|
486 | second_reference second() { return _second; } |
---|
487 | second_const_reference second() const { return _second; } |
---|
488 | |
---|
489 | void swap(compressed_pair& y) |
---|
490 | { |
---|
491 | using std::swap; |
---|
492 | swap(_first, y._first); |
---|
493 | swap(_second, y._second); |
---|
494 | } |
---|
495 | }; |
---|
496 | |
---|
497 | template <class T1, class T2> |
---|
498 | inline void swap(compressed_pair<T1, T2>& x, compressed_pair<T1, T2>& y) |
---|
499 | { |
---|
500 | x.swap(y); |
---|
501 | } |
---|
502 | |
---|
503 | #endif |
---|
504 | |
---|
505 | } // boost |
---|
506 | |
---|
507 | #endif // BOOST_OB_COMPRESSED_PAIR_HPP |
---|
508 | |
---|
509 | |
---|
510 | |
---|