1 | // Copyright (C) 2011 - 2012 Andrzej Krzemienski. |
2 | // |
3 | // Use, modification, and distribution is subject to the Boost Software |
4 | // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
5 | // http://www.boost.org/LICENSE_1_0.txt) |
6 | // |
7 | // The idea and interface is based on Boost.Optional library |
8 | // authored by Fernando Luis Cacciola Carballal |
9 | // |
10 | // From https://github.com/akrzemi1/Optional |
11 | // |
12 | // C10 |
13 | // - Move file to `c10` namespace. |
14 | // - Remove macro use in line 478 because the nvcc device compiler cannot handle |
15 | // it. |
16 | // - Revise constructor logic so that it is 1) consistent with c++ 17 standard |
17 | // documented here in (8): |
18 | // https://en.cppreference.com/w/cpp/utility/optional/optional, and 2) able to |
19 | // support initialization of optionals from convertible type U. |
20 | // - Remove the constructors for `optional(const T&)` and `optional(T&&)`, as |
21 | // they can be handled by the template<U=T> case with the default template |
22 | // argument. |
23 | // - Move `constexpr struct in_place_t {} in_place{}` to `c10/util/in_place.h` |
24 | // so that it can also be used in `c10/util/variant.h`. |
25 | // - Remove special cases for pre-c++14 compilers to make code simpler. |
26 | |
27 | #ifndef C10_UTIL_OPTIONAL_H_ |
28 | #define C10_UTIL_OPTIONAL_H_ |
29 | |
30 | #include <c10/macros/Macros.h> |
31 | #include <c10/util/ArrayRef.h> |
32 | #include <c10/util/in_place.h> |
33 | |
34 | #include <cassert> |
35 | #include <functional> |
36 | #include <initializer_list> |
37 | #include <stdexcept> |
38 | #include <string> |
39 | #include <type_traits> |
40 | #include <utility> |
41 | |
42 | #include <c10/util/C++17.h> |
43 | #include <c10/util/Metaprogramming.h> |
44 | |
45 | C10_CLANG_DIAGNOSTIC_PUSH() |
46 | #if C10_CLANG_HAS_WARNING("-Wstring-conversion") |
47 | C10_CLANG_DIAGNOSTIC_IGNORE("-Wstring-conversion" ) |
48 | #endif |
49 | #if C10_CLANG_HAS_WARNING("-Wshorten-64-to-32") |
50 | C10_CLANG_DIAGNOSTIC_IGNORE("-Wshorten-64-to-32" ) |
51 | #endif |
52 | #if C10_CLANG_HAS_WARNING("-Wimplicit-float-conversion") |
53 | C10_CLANG_DIAGNOSTIC_IGNORE("-Wimplicit-float-conversion" ) |
54 | #endif |
55 | #if C10_CLANG_HAS_WARNING("-Wimplicit-int-conversion") |
56 | C10_CLANG_DIAGNOSTIC_IGNORE("-Wimplicit-int-conversion" ) |
57 | #endif |
58 | |
59 | #define TR2_OPTIONAL_REQUIRES(...) \ |
60 | typename std::enable_if<__VA_ARGS__::value, bool>::type = false |
61 | |
62 | namespace c10 { |
63 | |
64 | // 20.5.4, optional for object types |
65 | template <class T> |
66 | class optional; |
67 | |
68 | // 20.5.5, optional for lvalue reference types |
69 | template <class T> |
70 | class optional<T&>; |
71 | |
72 | // workaround: std utility functions aren't constexpr yet |
73 | template <class T> |
74 | inline constexpr T&& constexpr_forward( |
75 | typename std::remove_reference<T>::type& t) noexcept { |
76 | return static_cast<T&&>(t); |
77 | } |
78 | |
79 | template <class T> |
80 | inline constexpr T&& constexpr_forward( |
81 | typename std::remove_reference<T>::type&& t) noexcept { |
82 | static_assert(!std::is_lvalue_reference<T>::value, "!!" ); |
83 | return static_cast<T&&>(t); |
84 | } |
85 | |
86 | template <class T> |
87 | inline constexpr typename std::remove_reference<T>::type&& constexpr_move( |
88 | T&& t) noexcept { |
89 | return static_cast<typename std::remove_reference<T>::type&&>(t); |
90 | } |
91 | |
92 | #if defined NDEBUG |
93 | #define TR2_OPTIONAL_ASSERTED_EXPRESSION(CHECK, EXPR) (EXPR) |
94 | #else |
95 | #define TR2_OPTIONAL_ASSERTED_EXPRESSION(CHECK, EXPR) \ |
96 | ((CHECK) ? (EXPR) : ([] { assert(!#CHECK); }(), (EXPR))) |
97 | #endif |
98 | |
99 | #if defined(__CUDA_ARCH__) |
100 | #define TR2_OPTIONAL_HOST_CONSTEXPR |
101 | #else |
102 | #define TR2_OPTIONAL_HOST_CONSTEXPR constexpr |
103 | #endif |
104 | |
105 | // Sphinx chokes on static_addressof, so exclude it from Doxygen |
106 | // generation. See https://github.com/sphinx-doc/sphinx/issues/7944 |
107 | // \cond |
108 | |
109 | namespace detail_ { |
110 | |
111 | // VS doesn't handle constexpr well, so we need to skip these stuff. |
112 | #if (defined _MSC_VER) |
113 | template <typename T> |
114 | T* static_addressof(T& ref) { |
115 | return std::addressof(ref); |
116 | } |
117 | #else |
118 | // static_addressof: a constexpr version of addressof |
119 | template <typename T> |
120 | struct has_overloaded_addressof { |
121 | template <class X> |
122 | constexpr static bool has_overload(...) { |
123 | return false; |
124 | } |
125 | |
126 | template <class X, size_t S = sizeof(std::declval<X&>().operator&())> |
127 | constexpr static bool has_overload(bool) { |
128 | return true; |
129 | } |
130 | |
131 | constexpr static bool value = has_overload<T>(true); |
132 | }; |
133 | |
134 | template <typename T, TR2_OPTIONAL_REQUIRES(!has_overloaded_addressof<T>)> |
135 | constexpr T* static_addressof(T& ref) { |
136 | return &ref; |
137 | } |
138 | |
139 | template <typename T, TR2_OPTIONAL_REQUIRES(has_overloaded_addressof<T>)> |
140 | T* static_addressof(T& ref) { |
141 | return std::addressof(ref); |
142 | } |
143 | #endif |
144 | |
145 | // the call to convert<A>(b) has return type A and converts b to type A iff b |
146 | // decltype(b) is implicitly convertible to A |
147 | template <class U> |
148 | constexpr U convert(U v) { |
149 | return v; |
150 | } |
151 | |
152 | } // namespace detail_ |
153 | |
154 | // \endcond |
155 | |
156 | constexpr struct trivial_init_t { |
157 | } trivial_init{}; |
158 | |
159 | // 20.5.7, Disengaged state indicator |
160 | struct nullopt_t { |
161 | constexpr explicit nullopt_t(int) {} |
162 | }; |
163 | constexpr nullopt_t nullopt{0}; |
164 | |
165 | // 20.5.8, class bad_optional_access |
166 | class bad_optional_access : public std::logic_error { |
167 | public: |
168 | explicit bad_optional_access(const std::string& what_arg) |
169 | : logic_error{what_arg} {} |
170 | explicit bad_optional_access(const char* what_arg) : logic_error{what_arg} {} |
171 | }; |
172 | |
173 | template <class T> |
174 | union storage_t { |
175 | unsigned char dummy_{}; |
176 | T value_; |
177 | |
178 | #if __cplusplus >= 202002L |
179 | constexpr |
180 | #endif |
181 | storage_t(trivial_init_t) noexcept { |
182 | new (&dummy_) unsigned char; |
183 | } |
184 | |
185 | template <class... Args> |
186 | constexpr storage_t(Args&&... args) |
187 | : value_(constexpr_forward<Args>(args)...) {} |
188 | |
189 | ~storage_t() {} |
190 | }; |
191 | |
192 | template <class T> |
193 | union constexpr_storage_t { |
194 | unsigned char dummy_; |
195 | T value_; |
196 | |
197 | #if __cplusplus >= 202002L |
198 | // C++20 lifted the requirement to initialize a union member in order to be |
199 | // constexpr. |
200 | constexpr constexpr_storage_t(trivial_init_t) noexcept { |
201 | new (&dummy_) unsigned char; |
202 | } |
203 | #else |
204 | constexpr constexpr_storage_t(trivial_init_t) noexcept : dummy_() {} |
205 | #endif |
206 | |
207 | template <class... Args> |
208 | constexpr constexpr_storage_t(Args&&... args) |
209 | : value_(constexpr_forward<Args>(args)...) {} |
210 | |
211 | ~constexpr_storage_t() = default; |
212 | }; |
213 | |
214 | template <class T> |
215 | struct optional_base { |
216 | bool init_; |
217 | storage_t<T> storage_; |
218 | |
219 | constexpr optional_base() noexcept : init_(false), storage_(trivial_init){}; |
220 | |
221 | explicit constexpr optional_base(const optional_base<T>& v) |
222 | : init_(v.init_), storage_(trivial_init) { |
223 | if (init_) { |
224 | ::new (dataptr()) T(v.storage_.value_); |
225 | } |
226 | } |
227 | |
228 | explicit constexpr optional_base(const T& v) : init_(true), storage_(v) {} |
229 | |
230 | explicit constexpr optional_base(optional_base<T>&& v) noexcept( |
231 | std::is_nothrow_move_constructible<T>::value) |
232 | : init_(v.init_), storage_(trivial_init) { |
233 | if (init_) { |
234 | ::new (dataptr()) T(std::move(v.storage_.value_)); |
235 | } |
236 | } |
237 | |
238 | explicit constexpr optional_base(T&& v) |
239 | : init_(true), storage_(constexpr_move(v)) {} |
240 | |
241 | template <class... Args> |
242 | explicit optional_base(in_place_t, Args&&... args) |
243 | : init_(true), storage_(constexpr_forward<Args>(args)...) {} |
244 | |
245 | template < |
246 | class U, |
247 | class... Args, |
248 | TR2_OPTIONAL_REQUIRES(std::is_constructible<T, std::initializer_list<U>>)> |
249 | explicit optional_base( |
250 | in_place_t, |
251 | std::initializer_list<U> il, |
252 | Args&&... args) |
253 | : init_(true), storage_(il, std::forward<Args>(args)...) {} |
254 | |
255 | optional_base& operator=(const optional_base& rhs) { |
256 | if (init_ && !rhs.init_) { |
257 | clear(); |
258 | } else if (!init_ && rhs.init_) { |
259 | init_ = true; |
260 | ::new (dataptr()) T(rhs.storage_.value_); |
261 | } else if (init_ && rhs.init_) { |
262 | storage_.value_ = rhs.storage_.value_; |
263 | } |
264 | return *this; |
265 | } |
266 | |
267 | optional_base& operator=(optional_base&& rhs) noexcept( |
268 | std::is_nothrow_move_assignable<T>::value&& |
269 | std::is_nothrow_move_constructible<T>::value) { |
270 | if (init_ && !rhs.init_) { |
271 | clear(); |
272 | } else if (!init_ && rhs.init_) { |
273 | init_ = true; |
274 | ::new (dataptr()) T(std::move(rhs.storage_.value_)); |
275 | } else if (init_ && rhs.init_) { |
276 | storage_.value_ = std::move(rhs.storage_.value_); |
277 | } |
278 | return *this; |
279 | } |
280 | |
281 | ~optional_base() { |
282 | if (init_) |
283 | storage_.value_.T::~T(); |
284 | } |
285 | |
286 | constexpr bool initialized() const noexcept { |
287 | return init_; |
288 | } |
289 | |
290 | void setInitialized(bool init) noexcept { |
291 | init_ = init; |
292 | } |
293 | |
294 | private: |
295 | typename std::remove_const<T>::type* dataptr() { |
296 | return std::addressof(storage_.value_); |
297 | } |
298 | |
299 | constexpr const T* dataptr() const { |
300 | return detail_::static_addressof(storage_.value_); |
301 | } |
302 | |
303 | void clear() noexcept { |
304 | if (init_) { |
305 | dataptr()->~T(); |
306 | } |
307 | init_ = false; |
308 | } |
309 | }; |
310 | |
311 | template <class T> |
312 | struct constexpr_optional_base { |
313 | bool init_; |
314 | constexpr_storage_t<T> storage_; |
315 | |
316 | constexpr constexpr_optional_base() noexcept |
317 | : init_(false), storage_(trivial_init){}; |
318 | |
319 | explicit constexpr constexpr_optional_base( |
320 | const constexpr_optional_base<T>& v) |
321 | : init_(v.init_), storage_(trivial_init) { |
322 | if (init_) { |
323 | ::new (dataptr()) T(v.storage_.value_); |
324 | } |
325 | } |
326 | |
327 | explicit constexpr constexpr_optional_base( |
328 | constexpr_optional_base<T>&& |
329 | v) noexcept(std::is_nothrow_move_constructible<T>::value) |
330 | : init_(v.init_), storage_(trivial_init) { |
331 | if (init_) { |
332 | ::new (dataptr()) T(std::move(v.storage_.value_)); |
333 | } |
334 | } |
335 | |
336 | explicit constexpr constexpr_optional_base(const T& v) |
337 | : init_(true), storage_(v) {} |
338 | |
339 | explicit constexpr constexpr_optional_base(T&& v) |
340 | : init_(true), storage_(constexpr_move(v)) {} |
341 | |
342 | template <class... Args> |
343 | explicit constexpr constexpr_optional_base(in_place_t, Args&&... args) |
344 | : init_(true), storage_(constexpr_forward<Args>(args)...) {} |
345 | |
346 | template < |
347 | class U, |
348 | class... Args, |
349 | TR2_OPTIONAL_REQUIRES(std::is_constructible<T, std::initializer_list<U>>)> |
350 | constexpr explicit constexpr_optional_base( |
351 | in_place_t, |
352 | std::initializer_list<U> il, |
353 | Args&&... args) |
354 | : init_(true), storage_(il, std::forward<Args>(args)...) {} |
355 | |
356 | ~constexpr_optional_base() = default; |
357 | |
358 | constexpr_optional_base& operator=(const constexpr_optional_base& rhs) { |
359 | if (init_ && !rhs.init_) { |
360 | clear(); |
361 | } else if (!init_ && rhs.init_) { |
362 | init_ = true; |
363 | ::new (dataptr()) T(rhs.storage_.value_); |
364 | } else if (init_ && rhs.init_) { |
365 | storage_.value_ = rhs.storage_.value_; |
366 | } |
367 | return *this; |
368 | } |
369 | |
370 | constexpr_optional_base& operator=(constexpr_optional_base&& rhs) noexcept( |
371 | std::is_nothrow_move_assignable<T>::value&& |
372 | std::is_nothrow_move_constructible<T>::value) { |
373 | if (init_ && !rhs.init_) { |
374 | clear(); |
375 | } else if (!init_ && rhs.init_) { |
376 | init_ = true; |
377 | ::new (dataptr()) T(std::move(rhs.storage_.value_)); |
378 | } else if (init_ && rhs.init_) { |
379 | storage_.value_ = std::move(rhs.storage_.value_); |
380 | } |
381 | return *this; |
382 | } |
383 | |
384 | constexpr bool initialized() const noexcept { |
385 | return init_; |
386 | } |
387 | void setInitialized(bool init) noexcept { |
388 | init_ = init; |
389 | } |
390 | |
391 | private: |
392 | typename std::remove_const<T>::type* dataptr() { |
393 | return std::addressof(storage_.value_); |
394 | } |
395 | |
396 | constexpr const T* dataptr() const { |
397 | return detail_::static_addressof(storage_.value_); |
398 | } |
399 | |
400 | void clear() noexcept { |
401 | init_ = false; |
402 | } |
403 | }; |
404 | |
405 | // HACK: Optimization for trivially copyable types. The mainline |
406 | // implementation fails to have trivial copy/move operations in these |
407 | // cases, and we care about them, so just implement that directly. |
408 | template <class T> |
409 | struct trivially_copyable_optimization_optional_base { |
410 | bool init_; |
411 | constexpr_storage_t<T> storage_; |
412 | |
413 | constexpr trivially_copyable_optimization_optional_base() noexcept |
414 | : init_(false), storage_(trivial_init) {} |
415 | |
416 | explicit constexpr trivially_copyable_optimization_optional_base(const T& v) |
417 | : init_(true), storage_(v) {} |
418 | |
419 | explicit constexpr trivially_copyable_optimization_optional_base(T&& v) |
420 | : init_(true), storage_(constexpr_move(v)) {} |
421 | |
422 | template <class... Args> |
423 | explicit constexpr trivially_copyable_optimization_optional_base( |
424 | in_place_t, |
425 | Args&&... args) |
426 | : init_(true), storage_(constexpr_forward<Args>(args)...) {} |
427 | |
428 | template < |
429 | class U, |
430 | class... Args, |
431 | TR2_OPTIONAL_REQUIRES(std::is_constructible<T, std::initializer_list<U>>)> |
432 | constexpr explicit trivially_copyable_optimization_optional_base( |
433 | in_place_t, |
434 | std::initializer_list<U> il, |
435 | Args&&... args) |
436 | : init_(true), storage_(il, std::forward<Args>(args)...) {} |
437 | |
438 | ~trivially_copyable_optimization_optional_base() = default; |
439 | |
440 | constexpr bool initialized() const noexcept { |
441 | return init_; |
442 | } |
443 | void setInitialized(bool init) noexcept { |
444 | init_ = init; |
445 | } |
446 | }; |
447 | |
448 | // HACK: Optimization for ArrayRef<T>. We take advantage of an unused |
449 | // bit pattern in ArrayRef (inspired by Arthur O'Dwyer's |
450 | // tombstone_traits -- see https://youtu.be/MWBfmmg8-Yo?t=2466) to |
451 | // keep the size of c10::optional::ArrayRef<T> down to 16 bytes, which |
452 | // allows it to be passed to functions in registers instead of getting |
453 | // passed in memory per item 5c of the classification algorithm in |
454 | // section 3.2.3 of the System V ABI document |
455 | // (https://www.uclibc.org/docs/psABI-x86_64.pdf). |
456 | template <class ArrayRefT> |
457 | class arrayref_optional_base { |
458 | public: |
459 | union storage { |
460 | struct raw { |
461 | // ArrayRef has the invariant that if Data is nullptr then |
462 | // Length must be zero, so this is an unused bit pattern. |
463 | const void* p = nullptr; |
464 | size_t sz = 1; |
465 | } uninitialized_{}; |
466 | ArrayRefT value_; |
467 | |
468 | constexpr storage() noexcept : uninitialized_() { |
469 | setUninitialized(); |
470 | } |
471 | |
472 | constexpr void setUninitialized() noexcept { |
473 | uninitialized_.p = nullptr; |
474 | uninitialized_.sz = 1; |
475 | } |
476 | |
477 | explicit constexpr storage(ArrayRefT& v) : value_(v) {} |
478 | |
479 | template <typename T> |
480 | explicit constexpr storage(const std::initializer_list<T>& v) : value_(v) {} |
481 | |
482 | template <class... Args> |
483 | explicit constexpr storage(Args&&... args) |
484 | : value_(constexpr_forward<Args>(args)...) {} |
485 | }; |
486 | |
487 | storage storage_; |
488 | |
489 | constexpr arrayref_optional_base() noexcept = default; |
490 | |
491 | explicit constexpr arrayref_optional_base(const ArrayRefT& v) : storage_(v) {} |
492 | |
493 | template <class... Args> |
494 | explicit constexpr arrayref_optional_base(in_place_t, Args&&... args) |
495 | : storage_(constexpr_forward<Args>(args)...) {} |
496 | |
497 | template <typename T> |
498 | explicit constexpr arrayref_optional_base( |
499 | in_place_t, |
500 | const std::initializer_list<T>& v) |
501 | : storage_(v) {} |
502 | |
503 | constexpr bool initialized() const noexcept { |
504 | return storage_.uninitialized_.p != nullptr || |
505 | storage_.uninitialized_.sz == 0; |
506 | } |
507 | |
508 | void setInitialized(bool init) noexcept { |
509 | if (!init) { |
510 | storage_.setUninitialized(); |
511 | } else { |
512 | assert(initialized()); |
513 | } |
514 | } |
515 | }; |
516 | |
517 | namespace detail_ { |
518 | template <typename T> |
519 | struct is_arrayref : std::false_type {}; |
520 | |
521 | template <typename T> |
522 | struct is_arrayref<c10::ArrayRef<T>> : std::true_type {}; |
523 | } // namespace detail_ |
524 | |
525 | template <class T> |
526 | using OptionalBase = std::conditional_t< |
527 | detail_::is_arrayref<T>::value, |
528 | arrayref_optional_base<T>, |
529 | std::conditional_t< |
530 | std::is_trivially_destructible<T>::value && |
531 | C10_IS_TRIVIALLY_COPYABLE(T) && |
532 | // Avoid using is_trivially_copy_{constructible,assignable} |
533 | // because old GCC versions don't support them. Also, |
534 | // is_trivially_copyable seems not to do what I expect, so check |
535 | // trivially_copyable_optimization_optional_base directly. |
536 | std::is_copy_constructible< |
537 | trivially_copyable_optimization_optional_base<T>>::value && |
538 | std::is_copy_assignable< |
539 | trivially_copyable_optimization_optional_base<T>>::value, |
540 | trivially_copyable_optimization_optional_base<T>, |
541 | std::conditional_t< |
542 | std::is_trivially_destructible<T>::value, // if possible |
543 | constexpr_optional_base<std::remove_const_t<T>>, // use base with |
544 | // trivial |
545 | // destructor |
546 | optional_base<std::remove_const_t<T>>>>>; |
547 | |
548 | template <class T> |
549 | class optional : private OptionalBase<T> { |
550 | template <class U> // re-declaration for nvcc on Windows. |
551 | using OptionalBase = std::conditional_t< |
552 | detail_::is_arrayref<U>::value, |
553 | arrayref_optional_base<U>, |
554 | std::conditional_t< |
555 | std::is_trivially_destructible<U>::value && |
556 | C10_IS_TRIVIALLY_COPYABLE(U) && |
557 | // Avoid using is_trivially_copy_{constructible,assignable} |
558 | // because old GCC versions don't support them. Also, |
559 | // is_trivially_copyable seems not to do what I expect, so |
560 | // check trivially_copyable_optimization_optional_base |
561 | // directly. |
562 | std::is_copy_constructible< |
563 | trivially_copyable_optimization_optional_base<U>>::value && |
564 | std::is_copy_assignable< |
565 | trivially_copyable_optimization_optional_base<U>>::value, |
566 | trivially_copyable_optimization_optional_base<U>, |
567 | std::conditional_t< |
568 | std::is_trivially_destructible<U>::value, // if possible |
569 | constexpr_optional_base<std::remove_const_t<U>>, // use base |
570 | // with |
571 | // trivial |
572 | // destructor |
573 | optional_base<std::remove_const_t<U>>>>>; |
574 | |
575 | static_assert( |
576 | !std::is_same<typename std::decay<T>::type, nullopt_t>::value, |
577 | "bad T" ); |
578 | static_assert( |
579 | !std::is_same<typename std::decay<T>::type, in_place_t>::value, |
580 | "bad T" ); |
581 | |
582 | constexpr bool initialized() const noexcept { |
583 | return OptionalBase<T>::initialized(); |
584 | } |
585 | typename std::remove_const<T>::type* dataptr() { |
586 | return std::addressof(OptionalBase<T>::storage_.value_); |
587 | } |
588 | constexpr const T* dataptr() const { |
589 | return detail_::static_addressof(OptionalBase<T>::storage_.value_); |
590 | } |
591 | |
592 | constexpr const T& contained_val() const& { |
593 | return OptionalBase<T>::storage_.value_; |
594 | } |
595 | constexpr T&& contained_val() && { |
596 | return std::move(OptionalBase<T>::storage_.value_); |
597 | } |
598 | constexpr T& contained_val() & { |
599 | return OptionalBase<T>::storage_.value_; |
600 | } |
601 | |
602 | void clear() noexcept { |
603 | if (initialized()) |
604 | dataptr()->~T(); |
605 | OptionalBase<T>::setInitialized(false); |
606 | } |
607 | |
608 | template <class... Args> |
609 | void initialize(Args&&... args) noexcept( |
610 | noexcept(T(std::forward<Args>(args)...))) { |
611 | assert(!initialized()); |
612 | ::new (static_cast<void*>(dataptr())) T(std::forward<Args>(args)...); |
613 | OptionalBase<T>::setInitialized(true); |
614 | } |
615 | |
616 | template <class U, class... Args> |
617 | void initialize(std::initializer_list<U> il, Args&&... args) noexcept( |
618 | noexcept(T(il, std::forward<Args>(args)...))) { |
619 | assert(!initialized()); |
620 | ::new (static_cast<void*>(dataptr())) T(il, std::forward<Args>(args)...); |
621 | OptionalBase<T>::setInitialized(true); |
622 | } |
623 | |
624 | public: |
625 | typedef T value_type; |
626 | |
627 | // 20.5.5.1, constructors |
628 | constexpr optional() noexcept = default; |
629 | constexpr optional(nullopt_t) noexcept : OptionalBase<T>(){}; |
630 | |
631 | optional(const optional& rhs) = default; |
632 | optional(optional&& rhs) = default; |
633 | |
634 | // see https://github.com/akrzemi1/Optional/issues/16 |
635 | // and https://en.cppreference.com/w/cpp/utility/optional/optional, |
636 | // in constructor 8, the std::optional spec can allow initialization |
637 | // of optionals from convertible type U |
638 | // |
639 | // 8 - implicit move construct from value |
640 | template < |
641 | typename U = T, |
642 | TR2_OPTIONAL_REQUIRES( |
643 | std::is_constructible<T, U&&>::value && |
644 | !std::is_same<typename std::decay<U>::type, in_place_t>::value && |
645 | !std::is_same<typename std::decay<U>::type, optional<T>>::value && |
646 | std::is_convertible<U&&, T>)> |
647 | constexpr optional(U&& u) : OptionalBase<T>(std::forward<U>(u)) {} |
648 | |
649 | // 8 - explicit move construct from value |
650 | template < |
651 | typename U = T, |
652 | TR2_OPTIONAL_REQUIRES( |
653 | std::is_constructible<T, U&&>::value && |
654 | !std::is_same<typename std::decay<U>::type, in_place_t>::value && |
655 | !std::is_same<typename std::decay<U>::type, optional<T>>::value && |
656 | !std::is_convertible<U&&, T>)> |
657 | explicit constexpr optional(U&& u) : OptionalBase<T>(std::forward<U>(u)) {} |
658 | |
659 | template <class... Args> |
660 | explicit constexpr optional(in_place_t, Args&&... args) |
661 | : OptionalBase<T>(in_place_t{}, constexpr_forward<Args>(args)...) {} |
662 | |
663 | template < |
664 | class U, |
665 | class... Args, |
666 | TR2_OPTIONAL_REQUIRES(std::is_constructible<T, std::initializer_list<U>>)> |
667 | constexpr explicit optional( |
668 | in_place_t, |
669 | std::initializer_list<U> il, |
670 | Args&&... args) |
671 | : OptionalBase<T>(in_place_t{}, il, constexpr_forward<Args>(args)...) {} |
672 | |
673 | // 20.5.4.2, Destructor |
674 | ~optional() = default; |
675 | |
676 | // 20.5.4.3, assignment |
677 | optional& operator=(nullopt_t) noexcept { |
678 | clear(); |
679 | return *this; |
680 | } |
681 | |
682 | optional& operator=(const optional& rhs) = default; |
683 | |
684 | optional& operator=(optional&& rhs) = default; |
685 | |
686 | template <class U = T> |
687 | auto operator=(U&& v) -> typename std::enable_if< |
688 | std::is_constructible<T, U>::value && |
689 | !std::is_same<typename std::decay<U>::type, optional<T>>::value && |
690 | (std::is_scalar<T>::value || |
691 | std::is_same<typename std::decay<U>::type, T>::value) && |
692 | std::is_assignable<T&, U>::value, |
693 | optional&>::type { |
694 | if (initialized()) { |
695 | contained_val() = std::forward<U>(v); |
696 | } else { |
697 | initialize(std::forward<U>(v)); |
698 | } |
699 | return *this; |
700 | } |
701 | |
702 | template <class... Args> |
703 | void emplace(Args&&... args) { |
704 | clear(); |
705 | initialize(std::forward<Args>(args)...); |
706 | } |
707 | |
708 | template <class U, class... Args> |
709 | void emplace(std::initializer_list<U> il, Args&&... args) { |
710 | clear(); |
711 | initialize<U, Args...>(il, std::forward<Args>(args)...); |
712 | } |
713 | |
714 | // 20.5.4.4, Swap |
715 | void swap(optional<T>& rhs) noexcept( |
716 | std::is_nothrow_move_constructible<T>::value&& noexcept( |
717 | std::swap(std::declval<T&>(), std::declval<T&>()))) { |
718 | if (initialized() == true && rhs.initialized() == false) { |
719 | rhs.initialize(std::move(**this)); |
720 | clear(); |
721 | } else if (initialized() == false && rhs.initialized() == true) { |
722 | initialize(std::move(*rhs)); |
723 | rhs.clear(); |
724 | } else if (initialized() == true && rhs.initialized() == true) { |
725 | using std::swap; |
726 | swap(**this, *rhs); |
727 | } |
728 | } |
729 | |
730 | // 20.5.4.5, Observers |
731 | |
732 | explicit constexpr operator bool() const noexcept { |
733 | return initialized(); |
734 | } |
735 | constexpr bool has_value() const noexcept { |
736 | return initialized(); |
737 | } |
738 | |
739 | TR2_OPTIONAL_HOST_CONSTEXPR T const* operator->() const { |
740 | return TR2_OPTIONAL_ASSERTED_EXPRESSION(initialized(), dataptr()); |
741 | } |
742 | |
743 | TR2_OPTIONAL_HOST_CONSTEXPR T* operator->() { |
744 | assert(initialized()); |
745 | return dataptr(); |
746 | } |
747 | |
748 | TR2_OPTIONAL_HOST_CONSTEXPR T const& operator*() const& { |
749 | return TR2_OPTIONAL_ASSERTED_EXPRESSION(initialized(), contained_val()); |
750 | } |
751 | |
752 | TR2_OPTIONAL_HOST_CONSTEXPR T& operator*() & { |
753 | assert(initialized()); |
754 | return contained_val(); |
755 | } |
756 | |
757 | TR2_OPTIONAL_HOST_CONSTEXPR T&& operator*() && { |
758 | assert(initialized()); |
759 | return constexpr_move(contained_val()); |
760 | } |
761 | |
762 | TR2_OPTIONAL_HOST_CONSTEXPR T const& value() const& { |
763 | return initialized() |
764 | ? contained_val() |
765 | : (throw bad_optional_access("bad optional access" ), contained_val()); |
766 | } |
767 | |
768 | TR2_OPTIONAL_HOST_CONSTEXPR T& value() & { |
769 | return initialized() |
770 | ? contained_val() |
771 | : (throw bad_optional_access("bad optional access" ), contained_val()); |
772 | } |
773 | |
774 | TR2_OPTIONAL_HOST_CONSTEXPR T&& value() && { |
775 | if (!initialized()) |
776 | throw bad_optional_access("bad optional access" ); |
777 | return std::move(contained_val()); |
778 | } |
779 | |
780 | template <class V> |
781 | constexpr T value_or(V&& v) const& { |
782 | return *this ? **this : detail_::convert<T>(constexpr_forward<V>(v)); |
783 | } |
784 | |
785 | template <class V> |
786 | constexpr T value_or(V&& v) && { |
787 | return *this |
788 | ? constexpr_move(const_cast<optional<T>&>(*this).contained_val()) |
789 | : detail_::convert<T>(constexpr_forward<V>(v)); |
790 | } |
791 | |
792 | // 20.6.3.6, modifiers |
793 | void reset() noexcept { |
794 | clear(); |
795 | } |
796 | }; |
797 | |
798 | template <class T, class F> |
799 | constexpr T value_or_else(const optional<T>& v, F&& func) { |
800 | static_assert( |
801 | std::is_convertible< |
802 | typename guts::infer_function_traits_t<F>::return_type, |
803 | T>::value, |
804 | "func parameters must be a callable that returns a type convertible to the value stored in the optional" ); |
805 | return v.has_value() ? *v : detail_::convert<T>(std::forward<F>(func)()); |
806 | } |
807 | |
808 | template <class T, class F> |
809 | constexpr T value_or_else(optional<T>&& v, F&& func) { |
810 | static_assert( |
811 | std::is_convertible< |
812 | typename guts::infer_function_traits_t<F>::return_type, |
813 | T>::value, |
814 | "func parameters must be a callable that returns a type convertible to the value stored in the optional" ); |
815 | return v.has_value() ? constexpr_move(std::move(v).contained_val()) |
816 | : detail_::convert<T>(std::forward<F>(func)()); |
817 | } |
818 | |
819 | // XXX: please refrain from using optional<T&>, since it is being against with |
820 | // the optional standard in c++ 17, see the debate and the details here: |
821 | // http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3406#rationale.refs |
822 | // if you need it, consider using optional<std::reference_wrapper<T>> or * |
823 | // pointer |
824 | // |
825 | // we leave the implementation here in case we want to reconsider using it in |
826 | // the future if it becomes a definitely necessary case. |
827 | template <class T> |
828 | class optional<T&> { |
829 | // add this assert to prevent user from using optional reference as indicated |
830 | // above |
831 | static_assert( |
832 | sizeof(T) == 0, |
833 | "optional references is ill-formed, \ |
834 | consider use optional of a std::reference_wrapper of type T to \ |
835 | hold a reference if you really need to" ); |
836 | |
837 | static_assert(!std::is_same<T, nullopt_t>::value, "bad T" ); |
838 | static_assert(!std::is_same<T, in_place_t>::value, "bad T" ); |
839 | T* ref; |
840 | |
841 | public: |
842 | // 20.5.5.1, construction/destruction |
843 | constexpr optional() noexcept : ref(nullptr) {} |
844 | |
845 | constexpr optional(nullopt_t) noexcept : ref(nullptr) {} |
846 | |
847 | template <typename U = T> |
848 | constexpr optional(U& u) noexcept : ref(detail_::static_addressof(u)) {} |
849 | |
850 | template <typename U = T> |
851 | optional(U&&) = delete; |
852 | |
853 | constexpr optional(const optional& rhs) noexcept : ref(rhs.ref) {} |
854 | |
855 | explicit constexpr optional(in_place_t, T& v) noexcept |
856 | : ref(detail_::static_addressof(v)) {} |
857 | |
858 | explicit optional(in_place_t, T&&) = delete; |
859 | |
860 | ~optional() = default; |
861 | |
862 | // 20.5.5.2, mutation |
863 | optional& operator=(nullopt_t) noexcept { |
864 | ref = nullptr; |
865 | return *this; |
866 | } |
867 | |
868 | // optional& operator=(const optional& rhs) noexcept { |
869 | // ref = rhs.ref; |
870 | // return *this; |
871 | // } |
872 | |
873 | // optional& operator=(optional&& rhs) noexcept { |
874 | // ref = rhs.ref; |
875 | // return *this; |
876 | // } |
877 | |
878 | template <typename U> |
879 | auto operator=(U&& rhs) noexcept -> typename std::enable_if< |
880 | std::is_same<typename std::decay<U>::type, optional<T&>>::value, |
881 | optional&>::type { |
882 | ref = rhs.ref; |
883 | return *this; |
884 | } |
885 | |
886 | template <typename U> |
887 | auto operator=(U&& rhs) noexcept -> typename std::enable_if< |
888 | !std::is_same<typename std::decay<U>::type, optional<T&>>::value, |
889 | optional&>::type = delete; |
890 | |
891 | void emplace(T& v) noexcept { |
892 | ref = detail_::static_addressof(v); |
893 | } |
894 | |
895 | void emplace(T&&) = delete; |
896 | |
897 | void swap(optional<T&>& rhs) noexcept { |
898 | std::swap(ref, rhs.ref); |
899 | } |
900 | |
901 | // 20.5.5.3, observers |
902 | TR2_OPTIONAL_HOST_CONSTEXPR T* operator->() const { |
903 | return TR2_OPTIONAL_ASSERTED_EXPRESSION(ref, ref); |
904 | } |
905 | |
906 | TR2_OPTIONAL_HOST_CONSTEXPR T& operator*() const { |
907 | return TR2_OPTIONAL_ASSERTED_EXPRESSION(ref, *ref); |
908 | } |
909 | |
910 | constexpr T& value() const { |
911 | return ref ? *ref |
912 | : (throw bad_optional_access("bad optional access" ), *ref); |
913 | } |
914 | |
915 | explicit constexpr operator bool() const noexcept { |
916 | return ref != nullptr; |
917 | } |
918 | |
919 | constexpr bool has_value() const noexcept { |
920 | return ref != nullptr; |
921 | } |
922 | |
923 | template <class V> |
924 | constexpr typename std::decay<T>::type value_or(V&& v) const { |
925 | return *this ? **this |
926 | : detail_::convert<typename std::decay<T>::type>( |
927 | constexpr_forward<V>(v)); |
928 | } |
929 | |
930 | // x.x.x.x, modifiers |
931 | void reset() noexcept { |
932 | ref = nullptr; |
933 | } |
934 | }; |
935 | |
936 | template <class T> |
937 | class optional<T&&> { |
938 | static_assert(sizeof(T) == 0, "optional rvalue references disallowed" ); |
939 | }; |
940 | |
941 | // 20.5.8, Relational operators |
942 | template <class T> |
943 | constexpr bool operator==(const optional<T>& x, const optional<T>& y) { |
944 | return bool(x) != bool(y) ? false : bool(x) == false ? true : *x == *y; |
945 | } |
946 | |
947 | template <class T> |
948 | constexpr bool operator!=(const optional<T>& x, const optional<T>& y) { |
949 | return !(x == y); |
950 | } |
951 | |
952 | template <class T> |
953 | constexpr bool operator<(const optional<T>& x, const optional<T>& y) { |
954 | return (!y) ? false : (!x) ? true : *x < *y; |
955 | } |
956 | |
957 | template <class T> |
958 | constexpr bool operator>(const optional<T>& x, const optional<T>& y) { |
959 | return (y < x); |
960 | } |
961 | |
962 | template <class T> |
963 | constexpr bool operator<=(const optional<T>& x, const optional<T>& y) { |
964 | return !(y < x); |
965 | } |
966 | |
967 | template <class T> |
968 | constexpr bool operator>=(const optional<T>& x, const optional<T>& y) { |
969 | return !(x < y); |
970 | } |
971 | |
972 | // 20.5.9, Comparison with nullopt |
973 | template <class T> |
974 | constexpr bool operator==(const optional<T>& x, nullopt_t) noexcept { |
975 | return (!x); |
976 | } |
977 | |
978 | template <class T> |
979 | constexpr bool operator==(nullopt_t, const optional<T>& x) noexcept { |
980 | return (!x); |
981 | } |
982 | |
983 | template <class T> |
984 | constexpr bool operator!=(const optional<T>& x, nullopt_t) noexcept { |
985 | return bool(x); |
986 | } |
987 | |
988 | template <class T> |
989 | constexpr bool operator!=(nullopt_t, const optional<T>& x) noexcept { |
990 | return bool(x); |
991 | } |
992 | |
993 | template <class T> |
994 | constexpr bool operator<(const optional<T>&, nullopt_t) noexcept { |
995 | return false; |
996 | } |
997 | |
998 | template <class T> |
999 | constexpr bool operator<(nullopt_t, const optional<T>& x) noexcept { |
1000 | return bool(x); |
1001 | } |
1002 | |
1003 | template <class T> |
1004 | constexpr bool operator<=(const optional<T>& x, nullopt_t) noexcept { |
1005 | return (!x); |
1006 | } |
1007 | |
1008 | template <class T> |
1009 | constexpr bool operator<=(nullopt_t, const optional<T>&) noexcept { |
1010 | return true; |
1011 | } |
1012 | |
1013 | template <class T> |
1014 | constexpr bool operator>(const optional<T>& x, nullopt_t) noexcept { |
1015 | return bool(x); |
1016 | } |
1017 | |
1018 | template <class T> |
1019 | constexpr bool operator>(nullopt_t, const optional<T>&) noexcept { |
1020 | return false; |
1021 | } |
1022 | |
1023 | template <class T> |
1024 | constexpr bool operator>=(const optional<T>&, nullopt_t) noexcept { |
1025 | return true; |
1026 | } |
1027 | |
1028 | template <class T> |
1029 | constexpr bool operator>=(nullopt_t, const optional<T>& x) noexcept { |
1030 | return (!x); |
1031 | } |
1032 | |
1033 | // 20.5.10, Comparison with T |
1034 | template <class T, class U> |
1035 | constexpr bool operator==(const optional<T>& x, const U& v) { |
1036 | return bool(x) ? *x == v : false; |
1037 | } |
1038 | |
1039 | template <class T, class U> |
1040 | constexpr bool operator==(const U& v, const optional<T>& x) { |
1041 | return bool(x) ? v == *x : false; |
1042 | } |
1043 | |
1044 | template <class T, class U> |
1045 | constexpr bool operator!=(const optional<T>& x, const U& v) { |
1046 | return bool(x) ? *x != v : true; |
1047 | } |
1048 | |
1049 | template <class T, class U> |
1050 | constexpr bool operator!=(const U& v, const optional<T>& x) { |
1051 | return bool(x) ? v != *x : true; |
1052 | } |
1053 | |
1054 | template <class T, class U> |
1055 | constexpr bool operator<(const optional<T>& x, const U& v) { |
1056 | return bool(x) ? *x < v : true; |
1057 | } |
1058 | |
1059 | template <class T, class U> |
1060 | constexpr bool operator>(const U& v, const optional<T>& x) { |
1061 | return bool(x) ? v > *x : true; |
1062 | } |
1063 | |
1064 | template <class T, class U> |
1065 | constexpr bool operator>(const optional<T>& x, const U& v) { |
1066 | return bool(x) ? *x > v : false; |
1067 | } |
1068 | |
1069 | template <class T, class U> |
1070 | constexpr bool operator<(const U& v, const optional<T>& x) { |
1071 | return bool(x) ? v < *x : false; |
1072 | } |
1073 | |
1074 | template <class T, class U> |
1075 | constexpr bool operator>=(const optional<T>& x, const U& v) { |
1076 | return bool(x) ? *x >= v : false; |
1077 | } |
1078 | |
1079 | template <class T, class U> |
1080 | constexpr bool operator<=(const U& v, const optional<T>& x) { |
1081 | return bool(x) ? v <= *x : false; |
1082 | } |
1083 | |
1084 | template <class T, class U> |
1085 | constexpr bool operator<=(const optional<T>& x, const U& v) { |
1086 | return bool(x) ? *x <= v : true; |
1087 | } |
1088 | |
1089 | template <class T, class U> |
1090 | constexpr bool operator>=(const U& v, const optional<T>& x) { |
1091 | return bool(x) ? v >= *x : true; |
1092 | } |
1093 | |
1094 | // Comparison of optional<T&> with T |
1095 | template <class T> |
1096 | constexpr bool operator==(const optional<T&>& x, const T& v) { |
1097 | return bool(x) ? *x == v : false; |
1098 | } |
1099 | |
1100 | template <class T> |
1101 | constexpr bool operator==(const T& v, const optional<T&>& x) { |
1102 | return bool(x) ? v == *x : false; |
1103 | } |
1104 | |
1105 | template <class T> |
1106 | constexpr bool operator!=(const optional<T&>& x, const T& v) { |
1107 | return bool(x) ? *x != v : true; |
1108 | } |
1109 | |
1110 | template <class T> |
1111 | constexpr bool operator!=(const T& v, const optional<T&>& x) { |
1112 | return bool(x) ? v != *x : true; |
1113 | } |
1114 | |
1115 | template <class T> |
1116 | constexpr bool operator<(const optional<T&>& x, const T& v) { |
1117 | return bool(x) ? *x < v : true; |
1118 | } |
1119 | |
1120 | template <class T> |
1121 | constexpr bool operator>(const T& v, const optional<T&>& x) { |
1122 | return bool(x) ? v > *x : true; |
1123 | } |
1124 | |
1125 | template <class T> |
1126 | constexpr bool operator>(const optional<T&>& x, const T& v) { |
1127 | return bool(x) ? *x > v : false; |
1128 | } |
1129 | |
1130 | template <class T> |
1131 | constexpr bool operator<(const T& v, const optional<T&>& x) { |
1132 | return bool(x) ? v < *x : false; |
1133 | } |
1134 | |
1135 | template <class T> |
1136 | constexpr bool operator>=(const optional<T&>& x, const T& v) { |
1137 | return bool(x) ? *x >= v : false; |
1138 | } |
1139 | |
1140 | template <class T> |
1141 | constexpr bool operator<=(const T& v, const optional<T&>& x) { |
1142 | return bool(x) ? v <= *x : false; |
1143 | } |
1144 | |
1145 | template <class T> |
1146 | constexpr bool operator<=(const optional<T&>& x, const T& v) { |
1147 | return bool(x) ? *x <= v : true; |
1148 | } |
1149 | |
1150 | template <class T> |
1151 | constexpr bool operator>=(const T& v, const optional<T&>& x) { |
1152 | return bool(x) ? v >= *x : true; |
1153 | } |
1154 | |
1155 | // Comparison of optional<T const&> with T |
1156 | template <class T> |
1157 | constexpr bool operator==(const optional<const T&>& x, const T& v) { |
1158 | return bool(x) ? *x == v : false; |
1159 | } |
1160 | |
1161 | template <class T> |
1162 | constexpr bool operator==(const T& v, const optional<const T&>& x) { |
1163 | return bool(x) ? v == *x : false; |
1164 | } |
1165 | |
1166 | template <class T> |
1167 | constexpr bool operator!=(const optional<const T&>& x, const T& v) { |
1168 | return bool(x) ? *x != v : true; |
1169 | } |
1170 | |
1171 | template <class T> |
1172 | constexpr bool operator!=(const T& v, const optional<const T&>& x) { |
1173 | return bool(x) ? v != *x : true; |
1174 | } |
1175 | |
1176 | template <class T> |
1177 | constexpr bool operator<(const optional<const T&>& x, const T& v) { |
1178 | return bool(x) ? *x < v : true; |
1179 | } |
1180 | |
1181 | template <class T> |
1182 | constexpr bool operator>(const T& v, const optional<const T&>& x) { |
1183 | return bool(x) ? v > *x : true; |
1184 | } |
1185 | |
1186 | template <class T> |
1187 | constexpr bool operator>(const optional<const T&>& x, const T& v) { |
1188 | return bool(x) ? *x > v : false; |
1189 | } |
1190 | |
1191 | template <class T> |
1192 | constexpr bool operator<(const T& v, const optional<const T&>& x) { |
1193 | return bool(x) ? v < *x : false; |
1194 | } |
1195 | |
1196 | template <class T> |
1197 | constexpr bool operator>=(const optional<const T&>& x, const T& v) { |
1198 | return bool(x) ? *x >= v : false; |
1199 | } |
1200 | |
1201 | template <class T> |
1202 | constexpr bool operator<=(const T& v, const optional<const T&>& x) { |
1203 | return bool(x) ? v <= *x : false; |
1204 | } |
1205 | |
1206 | template <class T> |
1207 | constexpr bool operator<=(const optional<const T&>& x, const T& v) { |
1208 | return bool(x) ? *x <= v : true; |
1209 | } |
1210 | |
1211 | template <class T> |
1212 | constexpr bool operator>=(const T& v, const optional<const T&>& x) { |
1213 | return bool(x) ? v >= *x : true; |
1214 | } |
1215 | |
1216 | // 20.5.12, Specialized algorithms |
1217 | template <class T> |
1218 | void swap(optional<T>& x, optional<T>& y) noexcept(noexcept(x.swap(y))) { |
1219 | x.swap(y); |
1220 | } |
1221 | |
1222 | template <class T> |
1223 | constexpr optional<typename std::decay<T>::type> make_optional(T&& v) { |
1224 | return optional<typename std::decay<T>::type>(constexpr_forward<T>(v)); |
1225 | } |
1226 | |
1227 | template <class X> |
1228 | constexpr optional<X&> make_optional(std::reference_wrapper<X> v) { |
1229 | return optional<X&>(v.get()); |
1230 | } |
1231 | |
1232 | } // namespace c10 |
1233 | |
1234 | namespace std { |
1235 | template <typename T> |
1236 | struct hash<c10::optional<T>> { |
1237 | typedef c10::invoke_result_t<std::hash<T>, T> result_type; |
1238 | typedef c10::optional<T> argument_type; |
1239 | |
1240 | constexpr result_type operator()(argument_type const& arg) const { |
1241 | return arg ? std::hash<T>{}(*arg) : result_type{}; |
1242 | } |
1243 | }; |
1244 | |
1245 | template <typename T> |
1246 | struct hash<c10::optional<T&>> { |
1247 | typedef typename hash<T>::result_type result_type; |
1248 | typedef c10::optional<T&> argument_type; |
1249 | |
1250 | constexpr result_type operator()(argument_type const& arg) const { |
1251 | return arg ? std::hash<T>{}(*arg) : result_type{}; |
1252 | } |
1253 | }; |
1254 | } // namespace std |
1255 | |
1256 | #undef TR2_OPTIONAL_REQUIRES |
1257 | #undef TR2_OPTIONAL_ASSERTED_EXPRESSION |
1258 | #undef TR2_OPTIONAL_HOST_CONSTEXPR |
1259 | |
1260 | C10_CLANG_DIAGNOSTIC_POP() |
1261 | |
1262 | #endif // C10_UTIL_OPTIONAL_H_ |
1263 | |