1 | |
2 | #ifndef BOOST_MPL_HAS_XXX_HPP_INCLUDED |
3 | #define BOOST_MPL_HAS_XXX_HPP_INCLUDED |
4 | |
5 | // Copyright Aleksey Gurtovoy 2002-2006 |
6 | // Copyright David Abrahams 2002-2003 |
7 | // Copyright Daniel Walker 2007 |
8 | // |
9 | // Distributed under the Boost Software License, Version 1.0. |
10 | // (See accompanying file LICENSE_1_0.txt or copy at |
11 | // http://www.boost.org/LICENSE_1_0.txt) |
12 | // |
13 | // See http://www.boost.org/libs/mpl for documentation. |
14 | |
15 | // $Id$ |
16 | // $Date$ |
17 | // $Revision$ |
18 | |
19 | #include <boost/mpl/bool.hpp> |
20 | #include <boost/mpl/aux_/na_spec.hpp> |
21 | #include <boost/mpl/aux_/type_wrapper.hpp> |
22 | #include <boost/mpl/aux_/yes_no.hpp> |
23 | #include <boost/mpl/aux_/config/gcc.hpp> |
24 | #include <boost/mpl/aux_/config/has_xxx.hpp> |
25 | #include <boost/mpl/aux_/config/msvc_typename.hpp> |
26 | #include <boost/mpl/aux_/config/msvc.hpp> |
27 | #include <boost/mpl/aux_/config/static_constant.hpp> |
28 | #include <boost/mpl/aux_/config/workaround.hpp> |
29 | |
30 | #include <boost/preprocessor/array/elem.hpp> |
31 | #include <boost/preprocessor/cat.hpp> |
32 | #include <boost/preprocessor/control/if.hpp> |
33 | #include <boost/preprocessor/repetition/enum_params.hpp> |
34 | #include <boost/preprocessor/repetition/enum_trailing_params.hpp> |
35 | |
36 | #if BOOST_WORKAROUND( BOOST_BORLANDC, BOOST_TESTED_AT(0x590) ) |
37 | # include <boost/type_traits/is_class.hpp> |
38 | #endif |
39 | |
40 | #if !defined(BOOST_MPL_CFG_NO_HAS_XXX) |
41 | |
42 | # if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) |
43 | |
44 | // agurt, 11/sep/02: MSVC-specific version (< 7.1), based on a USENET |
45 | // newsgroup's posting by John Madsen (comp.lang.c++.moderated, |
46 | // 1999-11-12 19:17:06 GMT); the code is _not_ standard-conforming, but |
47 | // it works way more reliably than the SFINAE-based implementation |
48 | |
49 | // Modified dwa 8/Oct/02 to handle reference types. |
50 | |
51 | # include <boost/mpl/if.hpp> |
52 | # include <boost/mpl/bool.hpp> |
53 | |
54 | namespace boost { namespace mpl { namespace aux { |
55 | |
56 | struct has_xxx_tag; |
57 | |
58 | #if BOOST_WORKAROUND(BOOST_MSVC, == 1300) |
59 | template< typename U > struct msvc_incomplete_array |
60 | { |
61 | typedef char (&type)[sizeof(U) + 1]; |
62 | }; |
63 | #endif |
64 | |
65 | template< typename T > |
66 | struct msvc_is_incomplete |
67 | { |
68 | // MSVC is capable of some kinds of SFINAE. If U is an incomplete |
69 | // type, it won't pick the second overload |
70 | static char tester(...); |
71 | |
72 | #if BOOST_WORKAROUND(BOOST_MSVC, == 1300) |
73 | template< typename U > |
74 | static typename msvc_incomplete_array<U>::type tester(type_wrapper<U>); |
75 | #else |
76 | template< typename U > |
77 | static char (& tester(type_wrapper<U>) )[sizeof(U)+1]; |
78 | #endif |
79 | |
80 | BOOST_STATIC_CONSTANT(bool, value = |
81 | sizeof(tester(type_wrapper<T>())) == 1 |
82 | ); |
83 | }; |
84 | |
85 | template<> |
86 | struct msvc_is_incomplete<int> |
87 | { |
88 | BOOST_STATIC_CONSTANT(bool, value = false); |
89 | }; |
90 | |
91 | }}} |
92 | |
93 | # define BOOST_MPL_HAS_XXX_TRAIT_NAMED_DEF_(trait, name, default_) \ |
94 | template< typename T, typename name = ::boost::mpl::aux::has_xxx_tag > \ |
95 | struct BOOST_PP_CAT(trait,_impl) : T \ |
96 | { \ |
97 | static boost::mpl::aux::no_tag \ |
98 | test(void(*)(::boost::mpl::aux::has_xxx_tag)); \ |
99 | \ |
100 | static boost::mpl::aux::yes_tag test(...); \ |
101 | \ |
102 | BOOST_STATIC_CONSTANT(bool, value = \ |
103 | sizeof(test(static_cast<void(*)(name)>(0))) \ |
104 | != sizeof(boost::mpl::aux::no_tag) \ |
105 | ); \ |
106 | typedef boost::mpl::bool_<value> type; \ |
107 | }; \ |
108 | \ |
109 | template< typename T, typename fallback_ = boost::mpl::bool_<default_> > \ |
110 | struct trait \ |
111 | : boost::mpl::if_c< \ |
112 | boost::mpl::aux::msvc_is_incomplete<T>::value \ |
113 | , boost::mpl::bool_<false> \ |
114 | , BOOST_PP_CAT(trait,_impl)<T> \ |
115 | >::type \ |
116 | { \ |
117 | }; \ |
118 | \ |
119 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, void) \ |
120 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, bool) \ |
121 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, char) \ |
122 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, signed char) \ |
123 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, unsigned char) \ |
124 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, signed short) \ |
125 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, unsigned short) \ |
126 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, signed int) \ |
127 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, unsigned int) \ |
128 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, signed long) \ |
129 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, unsigned long) \ |
130 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, float) \ |
131 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, double) \ |
132 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, long double) \ |
133 | /**/ |
134 | |
135 | # define BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, T) \ |
136 | template<> struct trait<T> \ |
137 | { \ |
138 | BOOST_STATIC_CONSTANT(bool, value = false); \ |
139 | typedef boost::mpl::bool_<false> type; \ |
140 | }; \ |
141 | /**/ |
142 | |
143 | #if !defined(BOOST_NO_INTRINSIC_WCHAR_T) |
144 | # define BOOST_MPL_HAS_XXX_TRAIT_NAMED_DEF(trait, name, unused) \ |
145 | BOOST_MPL_HAS_XXX_TRAIT_NAMED_DEF_(trait, name, unused) \ |
146 | BOOST_MPL_AUX_HAS_XXX_TRAIT_SPEC(trait, wchar_t) \ |
147 | /**/ |
148 | #else |
149 | # define BOOST_MPL_HAS_XXX_TRAIT_NAMED_DEF(trait, name, unused) \ |
150 | BOOST_MPL_HAS_XXX_TRAIT_NAMED_DEF_(trait, name, unused) \ |
151 | /**/ |
152 | #endif |
153 | |
154 | |
155 | // SFINAE-based implementations below are derived from a USENET newsgroup's |
156 | // posting by Rani Sharoni (comp.lang.c++.moderated, 2002-03-17 07:45:09 PST) |
157 | |
158 | # elif BOOST_WORKAROUND(BOOST_MSVC, <= 1400) \ |
159 | || (BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1800)) && defined(__CUDACC__)) \ |
160 | || BOOST_WORKAROUND(__IBMCPP__, <= 700) |
161 | |
162 | // MSVC 7.1 & MSVC 8.0 & VACPP |
163 | |
164 | // agurt, 15/jun/05: replace overload-based SFINAE implementation with SFINAE |
165 | // applied to partial specialization to fix some apparently random failures |
166 | // (thanks to Daniel Wallin for researching this!) |
167 | |
168 | # define BOOST_MPL_HAS_XXX_TRAIT_NAMED_DEF(trait, name, default_) \ |
169 | template< typename T > \ |
170 | struct BOOST_PP_CAT(trait, _msvc_sfinae_helper) \ |
171 | { \ |
172 | typedef void type; \ |
173 | };\ |
174 | \ |
175 | template< typename T, typename U = void > \ |
176 | struct BOOST_PP_CAT(trait,_impl_) \ |
177 | { \ |
178 | BOOST_STATIC_CONSTANT(bool, value = false); \ |
179 | typedef boost::mpl::bool_<value> type; \ |
180 | }; \ |
181 | \ |
182 | template< typename T > \ |
183 | struct BOOST_PP_CAT(trait,_impl_)< \ |
184 | T \ |
185 | , typename BOOST_PP_CAT(trait, _msvc_sfinae_helper)< typename T::name >::type \ |
186 | > \ |
187 | { \ |
188 | BOOST_STATIC_CONSTANT(bool, value = true); \ |
189 | typedef boost::mpl::bool_<value> type; \ |
190 | }; \ |
191 | \ |
192 | template< typename T, typename fallback_ = boost::mpl::bool_<default_> > \ |
193 | struct trait \ |
194 | : BOOST_PP_CAT(trait,_impl_)<T> \ |
195 | { \ |
196 | }; \ |
197 | /**/ |
198 | |
199 | # elif BOOST_WORKAROUND( BOOST_BORLANDC, BOOST_TESTED_AT(0x590) ) |
200 | |
201 | # define BOOST_MPL_HAS_XXX_TRAIT_NAMED_BCB_DEF(trait, trait_tester, name, default_) \ |
202 | template< typename T, bool IS_CLASS > \ |
203 | struct trait_tester \ |
204 | { \ |
205 | BOOST_STATIC_CONSTANT( bool, value = false ); \ |
206 | }; \ |
207 | template< typename T > \ |
208 | struct trait_tester< T, true > \ |
209 | { \ |
210 | struct trait_tester_impl \ |
211 | { \ |
212 | template < class U > \ |
213 | static int resolve( boost::mpl::aux::type_wrapper<U> const volatile * \ |
214 | , boost::mpl::aux::type_wrapper<typename U::name >* = 0 ); \ |
215 | static char resolve( ... ); \ |
216 | }; \ |
217 | typedef boost::mpl::aux::type_wrapper<T> t_; \ |
218 | BOOST_STATIC_CONSTANT( bool, value = ( sizeof( trait_tester_impl::resolve( static_cast< t_ * >(0) ) ) == sizeof(int) ) ); \ |
219 | }; \ |
220 | template< typename T, typename fallback_ = boost::mpl::bool_<default_> > \ |
221 | struct trait \ |
222 | { \ |
223 | BOOST_STATIC_CONSTANT( bool, value = (trait_tester< T, boost::is_class< T >::value >::value) ); \ |
224 | typedef boost::mpl::bool_< trait< T, fallback_ >::value > type; \ |
225 | }; |
226 | |
227 | # define BOOST_MPL_HAS_XXX_TRAIT_NAMED_DEF(trait, name, default_) \ |
228 | BOOST_MPL_HAS_XXX_TRAIT_NAMED_BCB_DEF( trait \ |
229 | , BOOST_PP_CAT(trait,_tester) \ |
230 | , name \ |
231 | , default_ ) \ |
232 | /**/ |
233 | |
234 | # else // other SFINAE-capable compilers |
235 | |
236 | # define BOOST_MPL_HAS_XXX_TRAIT_NAMED_DEF(trait, name, default_) \ |
237 | template< typename T, typename fallback_ = boost::mpl::bool_<default_> > \ |
238 | struct trait \ |
239 | { \ |
240 | struct gcc_3_2_wknd \ |
241 | { \ |
242 | template< typename U > \ |
243 | static boost::mpl::aux::yes_tag test( \ |
244 | boost::mpl::aux::type_wrapper<U> const volatile* \ |
245 | , boost::mpl::aux::type_wrapper<BOOST_MSVC_TYPENAME U::name>* = 0 \ |
246 | ); \ |
247 | \ |
248 | static boost::mpl::aux::no_tag test(...); \ |
249 | }; \ |
250 | \ |
251 | typedef boost::mpl::aux::type_wrapper<T> t_; \ |
252 | BOOST_STATIC_CONSTANT(bool, value = \ |
253 | sizeof(gcc_3_2_wknd::test(static_cast<t_*>(0))) \ |
254 | == sizeof(boost::mpl::aux::yes_tag) \ |
255 | ); \ |
256 | typedef boost::mpl::bool_<value> type; \ |
257 | }; \ |
258 | /**/ |
259 | |
260 | # endif // BOOST_WORKAROUND(BOOST_MSVC, <= 1300) |
261 | |
262 | |
263 | #else // BOOST_MPL_CFG_NO_HAS_XXX |
264 | |
265 | // placeholder implementation |
266 | |
267 | # define BOOST_MPL_HAS_XXX_TRAIT_NAMED_DEF(trait, name, default_) \ |
268 | template< typename T, typename fallback_ = boost::mpl::bool_<default_> > \ |
269 | struct trait \ |
270 | { \ |
271 | BOOST_STATIC_CONSTANT(bool, value = fallback_::value); \ |
272 | typedef fallback_ type; \ |
273 | }; \ |
274 | /**/ |
275 | |
276 | #endif |
277 | |
278 | #define BOOST_MPL_HAS_XXX_TRAIT_DEF(name) \ |
279 | BOOST_MPL_HAS_XXX_TRAIT_NAMED_DEF(BOOST_PP_CAT(has_,name), name, false) \ |
280 | /**/ |
281 | |
282 | |
283 | #if !defined(BOOST_MPL_CFG_NO_HAS_XXX_TEMPLATE) |
284 | |
285 | // Create a boolean Metafunction to detect a nested template |
286 | // member. This implementation is based on a USENET newsgroup's |
287 | // posting by Aleksey Gurtovoy (comp.lang.c++.moderated, 2002-03-19), |
288 | // Rani Sharoni's USENET posting cited above, the non-template has_xxx |
289 | // implementations above, and discussion on the Boost mailing list. |
290 | |
291 | # if !defined(BOOST_MPL_HAS_XXX_NO_WRAPPED_TYPES) |
292 | # if BOOST_WORKAROUND(BOOST_MSVC, <= 1400) |
293 | # define BOOST_MPL_HAS_XXX_NO_WRAPPED_TYPES 1 |
294 | # else |
295 | # define BOOST_MPL_HAS_XXX_NO_WRAPPED_TYPES 0 |
296 | # endif |
297 | # endif |
298 | |
299 | # if !defined(BOOST_MPL_HAS_XXX_NO_EXPLICIT_TEST_FUNCTION) |
300 | # if (defined(BOOST_NO_EXPLICIT_FUNCTION_TEMPLATE_ARGUMENTS)) |
301 | # define BOOST_MPL_HAS_XXX_NO_EXPLICIT_TEST_FUNCTION 1 |
302 | # else |
303 | # define BOOST_MPL_HAS_XXX_NO_EXPLICIT_TEST_FUNCTION 0 |
304 | # endif |
305 | # endif |
306 | |
307 | # if !defined(BOOST_MPL_HAS_XXX_NEEDS_TEMPLATE_SFINAE) |
308 | # if BOOST_WORKAROUND(BOOST_MSVC, <= 1400) |
309 | # define BOOST_MPL_HAS_XXX_NEEDS_TEMPLATE_SFINAE 1 |
310 | # else |
311 | # define BOOST_MPL_HAS_XXX_NEEDS_TEMPLATE_SFINAE 0 |
312 | # endif |
313 | # endif |
314 | |
315 | // NOTE: Many internal implementation macros take a Boost.Preprocessor |
316 | // array argument called args which is of the following form. |
317 | // ( 4, ( trait, name, max_arity, default_ ) ) |
318 | |
319 | # define BOOST_MPL_HAS_MEMBER_INTROSPECTION_NAME(args) \ |
320 | BOOST_PP_CAT(BOOST_PP_ARRAY_ELEM(0, args) , _introspect) \ |
321 | /**/ |
322 | |
323 | # define BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME(args, n) \ |
324 | BOOST_PP_CAT(BOOST_PP_CAT(BOOST_PP_ARRAY_ELEM(0, args) , _substitute), n) \ |
325 | /**/ |
326 | |
327 | # define BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args) \ |
328 | BOOST_PP_CAT(BOOST_PP_ARRAY_ELEM(0, args) , _test) \ |
329 | /**/ |
330 | |
331 | // Thanks to Guillaume Melquiond for pointing out the need for the |
332 | // "substitute" template as an argument to the overloaded test |
333 | // functions to get SFINAE to work for member templates with the |
334 | // correct name but different number of arguments. |
335 | # define BOOST_MPL_HAS_MEMBER_MULTI_SUBSTITUTE(z, n, args) \ |
336 | template< \ |
337 | template< BOOST_PP_ENUM_PARAMS(BOOST_PP_INC(n), typename V) > class V \ |
338 | > \ |
339 | struct BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME(args, n) { \ |
340 | }; \ |
341 | /**/ |
342 | |
343 | # define BOOST_MPL_HAS_MEMBER_SUBSTITUTE(args, substitute_macro) \ |
344 | BOOST_PP_REPEAT( \ |
345 | BOOST_PP_ARRAY_ELEM(2, args) \ |
346 | , BOOST_MPL_HAS_MEMBER_MULTI_SUBSTITUTE \ |
347 | , args \ |
348 | ) \ |
349 | /**/ |
350 | |
351 | # if !BOOST_MPL_HAS_XXX_NO_EXPLICIT_TEST_FUNCTION |
352 | # define BOOST_MPL_HAS_MEMBER_REJECT(args, member_macro) \ |
353 | template< typename V > \ |
354 | static boost::mpl::aux::no_tag \ |
355 | BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)(...); \ |
356 | /**/ |
357 | # else |
358 | # define BOOST_MPL_HAS_MEMBER_REJECT(args, member_macro) \ |
359 | static boost::mpl::aux::no_tag \ |
360 | BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)(...); \ |
361 | /**/ |
362 | # endif |
363 | |
364 | # if !BOOST_MPL_HAS_XXX_NO_WRAPPED_TYPES |
365 | # define BOOST_MPL_HAS_MEMBER_MULTI_ACCEPT(z, n, args) \ |
366 | template< typename V > \ |
367 | static boost::mpl::aux::yes_tag \ |
368 | BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)( \ |
369 | boost::mpl::aux::type_wrapper< V > const volatile* \ |
370 | , BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME(args, n) < \ |
371 | V::template BOOST_PP_ARRAY_ELEM(1, args) \ |
372 | >* = 0 \ |
373 | ); \ |
374 | /**/ |
375 | # define BOOST_MPL_HAS_MEMBER_ACCEPT(args, member_macro) \ |
376 | BOOST_PP_REPEAT( \ |
377 | BOOST_PP_ARRAY_ELEM(2, args) \ |
378 | , BOOST_MPL_HAS_MEMBER_MULTI_ACCEPT \ |
379 | , args \ |
380 | ) \ |
381 | /**/ |
382 | # else |
383 | # define BOOST_MPL_HAS_MEMBER_ACCEPT(args, member_macro) \ |
384 | template< typename V > \ |
385 | static boost::mpl::aux::yes_tag \ |
386 | BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)( \ |
387 | V const volatile* \ |
388 | , member_macro(args, V, T)* = 0 \ |
389 | ); \ |
390 | /**/ |
391 | # endif |
392 | |
393 | # if !BOOST_MPL_HAS_XXX_NO_EXPLICIT_TEST_FUNCTION |
394 | # define BOOST_MPL_HAS_MEMBER_TEST(args) \ |
395 | sizeof(BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)< U >(0)) \ |
396 | == sizeof(boost::mpl::aux::yes_tag) \ |
397 | /**/ |
398 | # else |
399 | # if !BOOST_MPL_HAS_XXX_NO_WRAPPED_TYPES |
400 | # define BOOST_MPL_HAS_MEMBER_TEST(args) \ |
401 | sizeof( \ |
402 | BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)( \ |
403 | static_cast< boost::mpl::aux::type_wrapper< U >* >(0) \ |
404 | ) \ |
405 | ) == sizeof(boost::mpl::aux::yes_tag) \ |
406 | /**/ |
407 | # else |
408 | # define BOOST_MPL_HAS_MEMBER_TEST(args) \ |
409 | sizeof( \ |
410 | BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)( \ |
411 | static_cast< U* >(0) \ |
412 | ) \ |
413 | ) == sizeof(boost::mpl::aux::yes_tag) \ |
414 | /**/ |
415 | # endif |
416 | # endif |
417 | |
418 | # define BOOST_MPL_HAS_MEMBER_INTROSPECT( \ |
419 | args, substitute_macro, member_macro \ |
420 | ) \ |
421 | template< typename U > \ |
422 | struct BOOST_MPL_HAS_MEMBER_INTROSPECTION_NAME(args) { \ |
423 | BOOST_MPL_HAS_MEMBER_SUBSTITUTE(args, substitute_macro) \ |
424 | BOOST_MPL_HAS_MEMBER_REJECT(args, member_macro) \ |
425 | BOOST_MPL_HAS_MEMBER_ACCEPT(args, member_macro) \ |
426 | BOOST_STATIC_CONSTANT( \ |
427 | bool, value = BOOST_MPL_HAS_MEMBER_TEST(args) \ |
428 | ); \ |
429 | typedef boost::mpl::bool_< value > type; \ |
430 | }; \ |
431 | /**/ |
432 | |
433 | # define BOOST_MPL_HAS_MEMBER_IMPLEMENTATION( \ |
434 | args, introspect_macro, substitute_macro, member_macro \ |
435 | ) \ |
436 | template< \ |
437 | typename T \ |
438 | , typename fallback_ \ |
439 | = boost::mpl::bool_< BOOST_PP_ARRAY_ELEM(3, args) > \ |
440 | > \ |
441 | class BOOST_PP_ARRAY_ELEM(0, args) { \ |
442 | introspect_macro(args, substitute_macro, member_macro) \ |
443 | public: \ |
444 | static const bool value \ |
445 | = BOOST_MPL_HAS_MEMBER_INTROSPECTION_NAME(args)< T >::value; \ |
446 | typedef typename BOOST_MPL_HAS_MEMBER_INTROSPECTION_NAME(args)< \ |
447 | T \ |
448 | >::type type; \ |
449 | }; \ |
450 | /**/ |
451 | |
452 | // BOOST_MPL_HAS_MEMBER_WITH_FUNCTION_SFINAE expands to the full |
453 | // implementation of the function-based metafunction. Compile with -E |
454 | // to see the preprocessor output for this macro. |
455 | # define BOOST_MPL_HAS_MEMBER_WITH_FUNCTION_SFINAE( \ |
456 | args, substitute_macro, member_macro \ |
457 | ) \ |
458 | BOOST_MPL_HAS_MEMBER_IMPLEMENTATION( \ |
459 | args \ |
460 | , BOOST_MPL_HAS_MEMBER_INTROSPECT \ |
461 | , substitute_macro \ |
462 | , member_macro \ |
463 | ) \ |
464 | /**/ |
465 | |
466 | # if BOOST_MPL_HAS_XXX_NEEDS_TEMPLATE_SFINAE |
467 | |
468 | # if !defined(BOOST_MPL_HAS_XXX_NEEDS_NAMESPACE_LEVEL_SUBSTITUTE) |
469 | # if BOOST_WORKAROUND(BOOST_MSVC, <= 1400) |
470 | # define BOOST_MPL_HAS_XXX_NEEDS_NAMESPACE_LEVEL_SUBSTITUTE 1 |
471 | # endif |
472 | # endif |
473 | |
474 | # if !BOOST_MPL_HAS_XXX_NEEDS_NAMESPACE_LEVEL_SUBSTITUTE |
475 | # define BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME_WITH_TEMPLATE_SFINAE( \ |
476 | args, n \ |
477 | ) \ |
478 | BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME(args, n) \ |
479 | /**/ |
480 | # else |
481 | # define BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME_WITH_TEMPLATE_SFINAE( \ |
482 | args, n \ |
483 | ) \ |
484 | BOOST_PP_CAT( \ |
485 | boost_mpl_has_xxx_ \ |
486 | , BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME(args, n) \ |
487 | ) \ |
488 | /**/ |
489 | # endif |
490 | |
491 | # define BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_TAG_NAME( \ |
492 | args \ |
493 | ) \ |
494 | BOOST_PP_CAT( \ |
495 | BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME_WITH_TEMPLATE_SFINAE( \ |
496 | args, 0 \ |
497 | ) \ |
498 | , _tag \ |
499 | ) \ |
500 | /**/ |
501 | |
502 | # define BOOST_MPL_HAS_MEMBER_MULTI_SUBSTITUTE_WITH_TEMPLATE_SFINAE( \ |
503 | z, n, args \ |
504 | ) \ |
505 | template< \ |
506 | template< BOOST_PP_ENUM_PARAMS(BOOST_PP_INC(n), typename U) > class U \ |
507 | > \ |
508 | struct BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME_WITH_TEMPLATE_SFINAE( \ |
509 | args, n \ |
510 | ) { \ |
511 | typedef \ |
512 | BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_TAG_NAME(args) \ |
513 | type; \ |
514 | }; \ |
515 | /**/ |
516 | |
517 | # define BOOST_MPL_HAS_MEMBER_SUBSTITUTE_WITH_TEMPLATE_SFINAE( \ |
518 | args, substitute_macro \ |
519 | ) \ |
520 | typedef void \ |
521 | BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_TAG_NAME(args); \ |
522 | BOOST_PP_REPEAT( \ |
523 | BOOST_PP_ARRAY_ELEM(2, args) \ |
524 | , BOOST_MPL_HAS_MEMBER_MULTI_SUBSTITUTE_WITH_TEMPLATE_SFINAE \ |
525 | , args \ |
526 | ) \ |
527 | /**/ |
528 | |
529 | # define BOOST_MPL_HAS_MEMBER_REJECT_WITH_TEMPLATE_SFINAE( \ |
530 | args, member_macro \ |
531 | ) \ |
532 | template< \ |
533 | typename U \ |
534 | , typename V \ |
535 | = BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_TAG_NAME(args) \ |
536 | > \ |
537 | struct BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args) { \ |
538 | BOOST_STATIC_CONSTANT(bool, value = false); \ |
539 | typedef boost::mpl::bool_< value > type; \ |
540 | }; \ |
541 | /**/ |
542 | |
543 | # define BOOST_MPL_HAS_MEMBER_MULTI_ACCEPT_WITH_TEMPLATE_SFINAE( \ |
544 | z, n, args \ |
545 | ) \ |
546 | template< typename U > \ |
547 | struct BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)< \ |
548 | U \ |
549 | , typename \ |
550 | BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME_WITH_TEMPLATE_SFINAE( \ |
551 | args, n \ |
552 | )< \ |
553 | BOOST_MSVC_TYPENAME U::BOOST_PP_ARRAY_ELEM(1, args)< > \ |
554 | >::type \ |
555 | > { \ |
556 | BOOST_STATIC_CONSTANT(bool, value = true); \ |
557 | typedef boost::mpl::bool_< value > type; \ |
558 | }; \ |
559 | /**/ |
560 | |
561 | # define BOOST_MPL_HAS_MEMBER_ACCEPT_WITH_TEMPLATE_SFINAE( \ |
562 | args, member_macro \ |
563 | ) \ |
564 | BOOST_PP_REPEAT( \ |
565 | BOOST_PP_ARRAY_ELEM(2, args) \ |
566 | , BOOST_MPL_HAS_MEMBER_MULTI_ACCEPT_WITH_TEMPLATE_SFINAE \ |
567 | , args \ |
568 | ) \ |
569 | /**/ |
570 | |
571 | # define BOOST_MPL_HAS_MEMBER_INTROSPECT_WITH_TEMPLATE_SFINAE( \ |
572 | args, substitute_macro, member_macro \ |
573 | ) \ |
574 | BOOST_MPL_HAS_MEMBER_REJECT_WITH_TEMPLATE_SFINAE(args, member_macro) \ |
575 | BOOST_MPL_HAS_MEMBER_ACCEPT_WITH_TEMPLATE_SFINAE(args, member_macro) \ |
576 | template< typename U > \ |
577 | struct BOOST_MPL_HAS_MEMBER_INTROSPECTION_NAME(args) \ |
578 | : BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)< U > { \ |
579 | }; \ |
580 | /**/ |
581 | |
582 | // BOOST_MPL_HAS_MEMBER_WITH_TEMPLATE_SFINAE expands to the full |
583 | // implementation of the template-based metafunction. Compile with -E |
584 | // to see the preprocessor output for this macro. |
585 | // |
586 | // Note that if BOOST_MPL_HAS_XXX_NEEDS_NAMESPACE_LEVEL_SUBSTITUTE is |
587 | // defined BOOST_MPL_HAS_MEMBER_SUBSTITUTE_WITH_TEMPLATE_SFINAE needs |
588 | // to be expanded at namespace level before |
589 | // BOOST_MPL_HAS_MEMBER_WITH_TEMPLATE_SFINAE can be used. |
590 | # define BOOST_MPL_HAS_MEMBER_WITH_TEMPLATE_SFINAE( \ |
591 | args, substitute_macro, member_macro \ |
592 | ) \ |
593 | BOOST_MPL_HAS_MEMBER_SUBSTITUTE_WITH_TEMPLATE_SFINAE( \ |
594 | args, substitute_macro \ |
595 | ) \ |
596 | BOOST_MPL_HAS_MEMBER_IMPLEMENTATION( \ |
597 | args \ |
598 | , BOOST_MPL_HAS_MEMBER_INTROSPECT_WITH_TEMPLATE_SFINAE \ |
599 | , substitute_macro \ |
600 | , member_macro \ |
601 | ) \ |
602 | /**/ |
603 | |
604 | # endif // BOOST_MPL_HAS_XXX_NEEDS_TEMPLATE_SFINAE |
605 | |
606 | // Note: In the current implementation the parameter and access macros |
607 | // are no longer expanded. |
608 | # if !BOOST_WORKAROUND(BOOST_MSVC, <= 1400) |
609 | # define BOOST_MPL_HAS_XXX_TEMPLATE_NAMED_DEF(trait, name, default_) \ |
610 | BOOST_MPL_HAS_MEMBER_WITH_FUNCTION_SFINAE( \ |
611 | ( 4, ( trait, name, BOOST_MPL_LIMIT_METAFUNCTION_ARITY, default_ ) ) \ |
612 | , BOOST_MPL_HAS_MEMBER_TEMPLATE_SUBSTITUTE_PARAMETER \ |
613 | , BOOST_MPL_HAS_MEMBER_TEMPLATE_ACCESS \ |
614 | ) \ |
615 | /**/ |
616 | # else |
617 | # define BOOST_MPL_HAS_XXX_TEMPLATE_NAMED_DEF(trait, name, default_) \ |
618 | BOOST_MPL_HAS_MEMBER_WITH_TEMPLATE_SFINAE( \ |
619 | ( 4, ( trait, name, BOOST_MPL_LIMIT_METAFUNCTION_ARITY, default_ ) ) \ |
620 | , BOOST_MPL_HAS_MEMBER_TEMPLATE_SUBSTITUTE_PARAMETER \ |
621 | , BOOST_MPL_HAS_MEMBER_TEMPLATE_ACCESS \ |
622 | ) \ |
623 | /**/ |
624 | # endif |
625 | |
626 | #else // BOOST_MPL_CFG_NO_HAS_XXX_TEMPLATE |
627 | |
628 | // placeholder implementation |
629 | |
630 | # define BOOST_MPL_HAS_XXX_TEMPLATE_NAMED_DEF(trait, name, default_) \ |
631 | template< typename T \ |
632 | , typename fallback_ = boost::mpl::bool_< default_ > > \ |
633 | struct trait { \ |
634 | BOOST_STATIC_CONSTANT(bool, value = fallback_::value); \ |
635 | typedef fallback_ type; \ |
636 | }; \ |
637 | /**/ |
638 | |
639 | #endif // BOOST_MPL_CFG_NO_HAS_XXX_TEMPLATE |
640 | |
641 | # define BOOST_MPL_HAS_XXX_TEMPLATE_DEF(name) \ |
642 | BOOST_MPL_HAS_XXX_TEMPLATE_NAMED_DEF( \ |
643 | BOOST_PP_CAT(has_, name), name, false \ |
644 | ) \ |
645 | /**/ |
646 | |
647 | #endif // BOOST_MPL_HAS_XXX_HPP_INCLUDED |
648 | |