Open3D (C++ API)  0.19.0
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Optional.h
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1// ----------------------------------------------------------------------------
2// - Open3D: www.open3d.org -
3// ----------------------------------------------------------------------------
4// Copyright (c) 2018-2024 www.open3d.org
5// SPDX-License-Identifier: MIT
6// ----------------------------------------------------------------------------
7// Copyright (C) 2011 - 2012 Andrzej Krzemienski.
8//
9// Use, modification, and distribution is subject to the Boost Software
10// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
11// http://www.boost.org/LICENSE_1_0.txt)
12//
13// The idea and interface is based on Boost.Optional library
14// authored by Fernando Luis Cacciola Carballal
15//
16// From https://github.com/akrzemi1/Optional
17//
18// C10
19// - Move to `c10` namespace.
20// - Remove macro use in line 478 because the nvcc device compiler cannot handle
21// it.
22// - revise constructor logic so that it is consistent with c++ 17 standard
23// documented here in (8):
24// https://en.cppreference.com/w/cpp/utility/optional/optional, and could be
25// able to support initialization of optionals from convertible type U, also
26// remove two old constructors optional(const T&) and optional(T&&) as it could
27// be handled by the template<U=T> case with default template argument.
28// - `constexpr struct in_place_t {} in_place{}` is moved to
29// `c10/util/in_place.h`, so that it can also be used in `c10/util/variant.h`.
30// - Remove special cases for pre-c++14 compilers to make code simpler
31//
32//
33// Open3D
34// - Namespace change: open3d::utility::optional
35
36#pragma once
37
38#include <cassert>
39#include <functional>
40#include <initializer_list>
41#include <stdexcept>
42#include <string>
43#include <type_traits>
44#include <utility>
45
46#define TR2_OPTIONAL_REQUIRES(...) \
47 typename std::enable_if<__VA_ARGS__::value, bool>::type = false
48
49namespace open3d {
50namespace utility {
51
52struct in_place_t {
53 explicit in_place_t() = default;
54};
55
56constexpr in_place_t in_place{};
57
58// 20.5.4, optional for object types
59template <class T>
60class optional;
61
62// 20.5.5, optional for lvalue reference types
63template <class T>
64class optional<T&>;
65
66// workaround: std utility functions aren't constexpr yet
67template <class T>
68inline constexpr T&& constexpr_forward(
69 typename std::remove_reference<T>::type& t) noexcept {
70 return static_cast<T&&>(t);
71}
72
73template <class T>
74inline constexpr T&& constexpr_forward(
75 typename std::remove_reference<T>::type&& t) noexcept {
76 static_assert(!std::is_lvalue_reference<T>::value, "!!");
77 return static_cast<T&&>(t);
78}
79
80template <class T>
81inline constexpr typename std::remove_reference<T>::type&& constexpr_move(
82 T&& t) noexcept {
83 return static_cast<typename std::remove_reference<T>::type&&>(t);
84}
85
86#if defined NDEBUG
87#define TR2_OPTIONAL_ASSERTED_EXPRESSION(CHECK, EXPR) (EXPR)
88#else
89#define TR2_OPTIONAL_ASSERTED_EXPRESSION(CHECK, EXPR) \
90 ((CHECK) ? (EXPR) : ([] { assert(!#CHECK); }(), (EXPR)))
91#endif
92
93#if defined(__CUDA_ARCH__)
94#define TR2_OPTIONAL_HOST_CONSTEXPR
95#else
96#define TR2_OPTIONAL_HOST_CONSTEXPR constexpr
97#endif
98
99namespace detail_ {
100
101// VS doesn't handle constexpr well, so we need to skip these stuff.
102#if (defined _MSC_VER)
103template <typename T>
104T* static_addressof(T& ref) {
105 return std::addressof(ref);
106}
107#else
108// static_addressof: a constexpr version of addressof
109template <typename T>
111 template <class X>
112 constexpr static bool has_overload(...) {
113 return false;
114 }
115
116 template <class X, size_t S = sizeof(std::declval<X&>().operator&())>
117 constexpr static bool has_overload(bool) {
118 return true;
119 }
120
121 constexpr static bool value = has_overload<T>(true);
122};
123
124template <typename T, TR2_OPTIONAL_REQUIRES(!has_overloaded_addressof<T>)>
125constexpr T* static_addressof(T& ref) {
126 return &ref;
127}
128
129template <typename T, TR2_OPTIONAL_REQUIRES(has_overloaded_addressof<T>)>
131 return std::addressof(ref);
132}
133#endif
134
135// the call to convert<A>(b) has return type A and converts b to type A iff b
136// decltype(b) is implicitly convertible to A
137template <class U>
138constexpr U convert(U v) {
139 return v;
140}
141
142} // namespace detail_
143
144constexpr struct trivial_init_t {
146
147// 20.5.7, Disengaged state indicator
148struct nullopt_t {
149 struct init {};
150 constexpr explicit nullopt_t(init) {}
151};
153
154// 20.5.8, class bad_optional_access
155class bad_optional_access : public std::logic_error {
156public:
157 explicit bad_optional_access(const std::string& what_arg)
158 : logic_error{what_arg} {}
159 explicit bad_optional_access(const char* what_arg)
160 : logic_error{what_arg} {}
161};
162
163template <class T>
165 unsigned char dummy_;
167
168 constexpr storage_t(trivial_init_t) noexcept : dummy_(){};
169
170 template <class... Args>
171 constexpr storage_t(Args&&... args)
172 : value_(constexpr_forward<Args>(args)...) {}
173
175};
176
177template <class T>
179 unsigned char dummy_;
181
182 constexpr constexpr_storage_t(trivial_init_t) noexcept : dummy_(){};
183
184 template <class... Args>
185 constexpr constexpr_storage_t(Args&&... args)
186 : value_(constexpr_forward<Args>(args)...) {}
187
189};
190
191template <class T>
193 bool init_;
195
196 constexpr optional_base() noexcept : init_(false), storage_(trivial_init){};
197
198 explicit constexpr optional_base(const T& v) : init_(true), storage_(v) {}
199
200 explicit constexpr optional_base(T&& v)
201 : init_(true), storage_(constexpr_move(v)) {}
202
203 template <class... Args>
204 explicit optional_base(in_place_t, Args&&... args)
205 : init_(true), storage_(constexpr_forward<Args>(args)...) {}
206
207 template <class U,
208 class... Args,
210 std::is_constructible<T, std::initializer_list<U>>)>
212 std::initializer_list<U> il,
213 Args&&... args)
214 : init_(true), storage_(il, std::forward<Args>(args)...) {}
215
217 if (init_) storage_.value_.T::~T();
218 }
219};
220
221template <class T>
223 bool init_;
225
226 constexpr constexpr_optional_base() noexcept
227 : init_(false), storage_(trivial_init){};
228
229 explicit constexpr constexpr_optional_base(const T& v)
230 : init_(true), storage_(v) {}
231
232 explicit constexpr constexpr_optional_base(T&& v)
233 : init_(true), storage_(constexpr_move(v)) {}
234
235 template <class... Args>
236 explicit constexpr constexpr_optional_base(in_place_t, Args&&... args)
237 : init_(true), storage_(constexpr_forward<Args>(args)...) {}
238
239 template <class U,
240 class... Args,
242 std::is_constructible<T, std::initializer_list<U>>)>
244 std::initializer_list<U> il,
245 Args&&... args)
246 : init_(true), storage_(il, std::forward<Args>(args)...) {}
247
249};
250
251template <class T>
252using OptionalBase = typename std::conditional<
253 std::is_trivially_destructible<T>::value, // if possible
254 constexpr_optional_base<typename std::remove_const<
255 T>::type>, // use base with trivial destructor
257
258template <class T>
259class optional : private OptionalBase<T> {
260 template <class U> // re-declaration for nvcc on Windows.
261 using OptionalBase = typename std::conditional<
262 std::is_trivially_destructible<U>::value, // if possible
263 constexpr_optional_base<typename std::remove_const<
264 U>::type>, // use base with trivial destructor
266
267 static_assert(!std::is_same<typename std::decay<T>::type, nullopt_t>::value,
268 "bad T");
269 static_assert(
270 !std::is_same<typename std::decay<T>::type, in_place_t>::value,
271 "bad T");
272
273 constexpr bool initialized() const noexcept {
274 return OptionalBase<T>::init_;
275 }
276 typename std::remove_const<T>::type* dataptr() {
277 return std::addressof(OptionalBase<T>::storage_.value_);
278 }
279 constexpr const T* dataptr() const {
280 return detail_::static_addressof(OptionalBase<T>::storage_.value_);
281 }
282
283 constexpr const T& contained_val() const& {
284 return OptionalBase<T>::storage_.value_;
285 }
286 constexpr T&& contained_val() && {
287 return std::move(OptionalBase<T>::storage_.value_);
288 }
289 constexpr T& contained_val() & { return OptionalBase<T>::storage_.value_; }
290
291 void clear() noexcept {
292 if (initialized()) dataptr()->~T();
293 OptionalBase<T>::init_ = false;
294 }
295
296 template <class... Args>
297 void initialize(Args&&... args) noexcept(
298 noexcept(T(std::forward<Args>(args)...))) {
299 assert(!OptionalBase<T>::init_);
300 ::new (static_cast<void*>(dataptr())) T(std::forward<Args>(args)...);
301 OptionalBase<T>::init_ = true;
302 }
303
304 template <class U, class... Args>
305 void initialize(std::initializer_list<U> il, Args&&... args) noexcept(
306 noexcept(T(il, std::forward<Args>(args)...))) {
307 assert(!OptionalBase<T>::init_);
308 ::new (static_cast<void*>(dataptr()))
309 T(il, std::forward<Args>(args)...);
310 OptionalBase<T>::init_ = true;
311 }
312
313public:
314 typedef T value_type;
315
316 // 20.5.5.1, constructors
317 constexpr optional() noexcept : OptionalBase<T>(){};
318 constexpr optional(nullopt_t) noexcept : OptionalBase<T>(){};
319
320 optional(const optional& rhs) : OptionalBase<T>() {
321 if (rhs.initialized()) {
322 ::new (static_cast<void*>(dataptr())) T(*rhs);
323 OptionalBase<T>::init_ = true;
324 }
325 }
326
327 optional(optional&& rhs) noexcept(
328 std::is_nothrow_move_constructible<T>::value)
329 : OptionalBase<T>() {
330 if (rhs.initialized()) {
331 ::new (static_cast<void*>(dataptr())) T(std::move(*rhs));
332 OptionalBase<T>::init_ = true;
333 }
334 }
335
336 // see https://github.com/akrzemi1/Optional/issues/16
337 // and https://en.cppreference.com/w/cpp/utility/optional/optional,
338 // in constructor 8, the std::optional spec can allow initialization
339 // of optionals from convertible type U
340 //
341 // 8 - implicit move construct from value
342 template <typename U = T,
343 TR2_OPTIONAL_REQUIRES(std::is_constructible<T, U&&>::value &&
344 !std::is_same<typename std::decay<U>::type,
346 !std::is_same<typename std::decay<U>::type,
348 std::is_convertible<U&&, T>)>
349 constexpr optional(U&& u) : OptionalBase<T>(std::forward<U>(u)) {}
350
351 // 8 - explicit move construct from value
352 template <typename U = T,
353 TR2_OPTIONAL_REQUIRES(std::is_constructible<T, U&&>::value &&
354 !std::is_same<typename std::decay<U>::type,
356 !std::is_same<typename std::decay<U>::type,
358 !std::is_convertible<U&&, T>)>
359 explicit constexpr optional(U&& u) : OptionalBase<T>(std::forward<U>(u)) {}
360
361 template <class... Args>
362 explicit constexpr optional(in_place_t, Args&&... args)
363 : OptionalBase<T>(in_place_t{}, constexpr_forward<Args>(args)...) {}
364
365 template <class U,
366 class... Args,
368 std::is_constructible<T, std::initializer_list<U>>)>
369 constexpr explicit optional(in_place_t,
370 std::initializer_list<U> il,
371 Args&&... args)
372 : OptionalBase<T>(in_place_t{}, il, constexpr_forward<Args>(args)...) {}
373
374 // 20.5.4.2, Destructor
375 ~optional() = default;
376
377 // 20.5.4.3, assignment
379 clear();
380 return *this;
381 }
382
384 if (initialized() == true && rhs.initialized() == false)
385 clear();
386 else if (initialized() == false && rhs.initialized() == true)
387 initialize(*rhs);
388 else if (initialized() == true && rhs.initialized() == true)
389 contained_val() = *rhs;
390 return *this;
391 }
392
393 optional& operator=(optional&& rhs) noexcept(
394 std::is_nothrow_move_assignable<T>::value&&
395 std::is_nothrow_move_constructible<T>::value) {
396 if (initialized() == true && rhs.initialized() == false)
397 clear();
398 else if (initialized() == false && rhs.initialized() == true)
399 initialize(std::move(*rhs));
400 else if (initialized() == true && rhs.initialized() == true)
401 contained_val() = std::move(*rhs);
402 return *this;
403 }
404
405 template <class U = T>
406 auto operator=(U&& v) -> typename std::enable_if<
407 std::is_constructible<T, U>::value &&
408 !std::is_same<typename std::decay<U>::type,
410 (std::is_scalar<T>::value ||
411 std::is_same<typename std::decay<U>::type, T>::value) &&
412 std::is_assignable<T&, U>::value,
414 if (initialized()) {
415 contained_val() = std::forward<U>(v);
416 } else {
417 initialize(std::forward<U>(v));
418 }
419 return *this;
420 }
421
422 template <class... Args>
423 void emplace(Args&&... args) {
424 clear();
425 initialize(std::forward<Args>(args)...);
426 }
427
428 template <class U, class... Args>
429 void emplace(std::initializer_list<U> il, Args&&... args) {
430 clear();
431 initialize<U, Args...>(il, std::forward<Args>(args)...);
432 }
433
434 // 20.5.4.4, Swap
435 void swap(optional<T>& rhs) noexcept(
436 std::is_nothrow_move_constructible<T>::value&& noexcept(
437 std::swap(std::declval<T&>(), std::declval<T&>()))) {
438 if (initialized() == true && rhs.initialized() == false) {
439 rhs.initialize(std::move(**this));
440 clear();
441 } else if (initialized() == false && rhs.initialized() == true) {
442 initialize(std::move(*rhs));
443 rhs.clear();
444 } else if (initialized() == true && rhs.initialized() == true) {
445 using std::swap;
446 swap(**this, *rhs);
447 }
448 }
449
450 // 20.5.4.5, Observers
451
452 explicit constexpr operator bool() const noexcept { return initialized(); }
453 constexpr bool has_value() const noexcept { return initialized(); }
454
456 return TR2_OPTIONAL_ASSERTED_EXPRESSION(initialized(), dataptr());
457 }
458
460 assert(initialized());
461 return dataptr();
462 }
463
465 return TR2_OPTIONAL_ASSERTED_EXPRESSION(initialized(), contained_val());
466 }
467
469 assert(initialized());
470 return contained_val();
471 }
472
474 assert(initialized());
475 return constexpr_move(contained_val());
476 }
477
479 return initialized()
480 ? contained_val()
481 : (throw bad_optional_access("bad optional access"),
482 contained_val());
483 }
484
486 return initialized()
487 ? contained_val()
488 : (throw bad_optional_access("bad optional access"),
489 contained_val());
490 }
491
493 if (!initialized()) throw bad_optional_access("bad optional access");
494 return std::move(contained_val());
495 }
496
497 template <class V>
498 constexpr T value_or(V&& v) const& {
499 return *this ? **this : detail_::convert<T>(constexpr_forward<V>(v));
500 }
501
502 template <class V>
503 constexpr T value_or(V&& v) && {
504 return *this ? constexpr_move(
505 const_cast<optional<T>&>(*this).contained_val())
506 : detail_::convert<T>(constexpr_forward<V>(v));
507 }
508
509 // 20.6.3.6, modifiers
510 void reset() noexcept { clear(); }
511};
512
513// XXX: please refrain from using optional<T&>, since it is being against with
514// the optional standard in c++ 17, see the debate and the details here:
515// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3406#rationale.refs
516// if you need it, consider using optional<std::reference_wrapper<T>> or *
517// pointer
518//
519// we leave the implementation here in case we want to reconsider using it in
520// the future if it becomes a definitely necessary case.
521template <class T>
522class optional<T&> {
523 // add this assert to prevent user from using optional reference as
524 // indicated above
525 static_assert(sizeof(T) == 0,
526 "optional references is ill-formed, \
527 consider use optional of a std::reference_wrapper of type T to \
528 hold a reference if you really need to");
529
530 static_assert(!std::is_same<T, nullopt_t>::value, "bad T");
531 static_assert(!std::is_same<T, in_place_t>::value, "bad T");
532 T* ref;
533
534public:
535 // 20.5.5.1, construction/destruction
536 constexpr optional() noexcept : ref(nullptr) {}
537
538 constexpr optional(nullopt_t) noexcept : ref(nullptr) {}
539
540 template <typename U = T>
541 constexpr optional(U& u) noexcept : ref(detail_::static_addressof(u)) {}
542
543 template <typename U = T>
544 optional(U&&) = delete;
545
546 constexpr optional(const optional& rhs) noexcept : ref(rhs.ref) {}
547
548 explicit constexpr optional(in_place_t, T& v) noexcept
549 : ref(detail_::static_addressof(v)) {}
550
551 explicit optional(in_place_t, T&&) = delete;
552
553 ~optional() = default;
554
555 // 20.5.5.2, mutation
557 ref = nullptr;
558 return *this;
559 }
560
561 // optional& operator=(const optional& rhs) noexcept {
562 // ref = rhs.ref;
563 // return *this;
564 // }
565
566 // optional& operator=(optional&& rhs) noexcept {
567 // ref = rhs.ref;
568 // return *this;
569 // }
570
571 template <typename U>
572 auto operator=(U&& rhs) noexcept -> typename std::enable_if<
573 std::is_same<typename std::decay<U>::type, optional<T&>>::value,
575 ref = rhs.ref;
576 return *this;
577 }
578
579 template <typename U>
580 auto operator=(U&& rhs) noexcept -> typename std::enable_if<
581 !std::is_same<typename std::decay<U>::type, optional<T&>>::value,
582 optional&>::type = delete;
583
584 void emplace(T& v) noexcept { ref = detail_::static_addressof(v); }
585
586 void emplace(T&&) = delete;
587
588 void swap(optional<T&>& rhs) noexcept { std::swap(ref, rhs.ref); }
589
590 // 20.5.5.3, observers
594
598
599 constexpr T& value() const {
600 return ref ? *ref
601 : (throw bad_optional_access("bad optional access"), *ref);
602 }
603
604 explicit constexpr operator bool() const noexcept { return ref != nullptr; }
605
606 constexpr bool has_value() const noexcept { return ref != nullptr; }
607
608 template <class V>
609 constexpr typename std::decay<T>::type value_or(V&& v) const {
610 return *this ? **this
611 : detail_::convert<typename std::decay<T>::type>(
612 constexpr_forward<V>(v));
613 }
614
615 // x.x.x.x, modifiers
616 void reset() noexcept { ref = nullptr; }
617};
618
619template <class T>
620class optional<T&&> {
621 static_assert(sizeof(T) == 0, "optional rvalue references disallowed");
622};
623
624// 20.5.8, Relational operators
625template <class T>
626constexpr bool operator==(const optional<T>& x, const optional<T>& y) {
627 return bool(x) != bool(y) ? false : bool(x) == false ? true : *x == *y;
628}
629
630template <class T>
631constexpr bool operator!=(const optional<T>& x, const optional<T>& y) {
632 return !(x == y);
633}
634
635template <class T>
636constexpr bool operator<(const optional<T>& x, const optional<T>& y) {
637 return (!y) ? false : (!x) ? true : *x < *y;
638}
639
640template <class T>
641constexpr bool operator>(const optional<T>& x, const optional<T>& y) {
642 return (y < x);
643}
644
645template <class T>
646constexpr bool operator<=(const optional<T>& x, const optional<T>& y) {
647 return !(y < x);
648}
649
650template <class T>
651constexpr bool operator>=(const optional<T>& x, const optional<T>& y) {
652 return !(x < y);
653}
654
655// 20.5.9, Comparison with nullopt
656template <class T>
657constexpr bool operator==(const optional<T>& x, nullopt_t) noexcept {
658 return (!x);
659}
660
661template <class T>
662constexpr bool operator==(nullopt_t, const optional<T>& x) noexcept {
663 return (!x);
664}
665
666template <class T>
667constexpr bool operator!=(const optional<T>& x, nullopt_t) noexcept {
668 return bool(x);
669}
670
671template <class T>
672constexpr bool operator!=(nullopt_t, const optional<T>& x) noexcept {
673 return bool(x);
674}
675
676template <class T>
677constexpr bool operator<(const optional<T>&, nullopt_t) noexcept {
678 return false;
679}
680
681template <class T>
682constexpr bool operator<(nullopt_t, const optional<T>& x) noexcept {
683 return bool(x);
684}
685
686template <class T>
687constexpr bool operator<=(const optional<T>& x, nullopt_t) noexcept {
688 return (!x);
689}
690
691template <class T>
692constexpr bool operator<=(nullopt_t, const optional<T>&) noexcept {
693 return true;
694}
695
696template <class T>
697constexpr bool operator>(const optional<T>& x, nullopt_t) noexcept {
698 return bool(x);
699}
700
701template <class T>
702constexpr bool operator>(nullopt_t, const optional<T>&) noexcept {
703 return false;
704}
705
706template <class T>
707constexpr bool operator>=(const optional<T>&, nullopt_t) noexcept {
708 return true;
709}
710
711template <class T>
712constexpr bool operator>=(nullopt_t, const optional<T>& x) noexcept {
713 return (!x);
714}
715
716// 20.5.10, Comparison with T
717template <class T>
718constexpr bool operator==(const optional<T>& x, const T& v) {
719 return bool(x) ? *x == v : false;
720}
721
722template <class T>
723constexpr bool operator==(const T& v, const optional<T>& x) {
724 return bool(x) ? v == *x : false;
725}
726
727template <class T>
728constexpr bool operator!=(const optional<T>& x, const T& v) {
729 return bool(x) ? *x != v : true;
730}
731
732template <class T>
733constexpr bool operator!=(const T& v, const optional<T>& x) {
734 return bool(x) ? v != *x : true;
735}
736
737template <class T>
738constexpr bool operator<(const optional<T>& x, const T& v) {
739 return bool(x) ? *x < v : true;
740}
741
742template <class T>
743constexpr bool operator>(const T& v, const optional<T>& x) {
744 return bool(x) ? v > *x : true;
745}
746
747template <class T>
748constexpr bool operator>(const optional<T>& x, const T& v) {
749 return bool(x) ? *x > v : false;
750}
751
752template <class T>
753constexpr bool operator<(const T& v, const optional<T>& x) {
754 return bool(x) ? v < *x : false;
755}
756
757template <class T>
758constexpr bool operator>=(const optional<T>& x, const T& v) {
759 return bool(x) ? *x >= v : false;
760}
761
762template <class T>
763constexpr bool operator<=(const T& v, const optional<T>& x) {
764 return bool(x) ? v <= *x : false;
765}
766
767template <class T>
768constexpr bool operator<=(const optional<T>& x, const T& v) {
769 return bool(x) ? *x <= v : true;
770}
771
772template <class T>
773constexpr bool operator>=(const T& v, const optional<T>& x) {
774 return bool(x) ? v >= *x : true;
775}
776
777// Comparison of optional<T&> with T
778template <class T>
779constexpr bool operator==(const optional<T&>& x, const T& v) {
780 return bool(x) ? *x == v : false;
781}
782
783template <class T>
784constexpr bool operator==(const T& v, const optional<T&>& x) {
785 return bool(x) ? v == *x : false;
786}
787
788template <class T>
789constexpr bool operator!=(const optional<T&>& x, const T& v) {
790 return bool(x) ? *x != v : true;
791}
792
793template <class T>
794constexpr bool operator!=(const T& v, const optional<T&>& x) {
795 return bool(x) ? v != *x : true;
796}
797
798template <class T>
799constexpr bool operator<(const optional<T&>& x, const T& v) {
800 return bool(x) ? *x < v : true;
801}
802
803template <class T>
804constexpr bool operator>(const T& v, const optional<T&>& x) {
805 return bool(x) ? v > *x : true;
806}
807
808template <class T>
809constexpr bool operator>(const optional<T&>& x, const T& v) {
810 return bool(x) ? *x > v : false;
811}
812
813template <class T>
814constexpr bool operator<(const T& v, const optional<T&>& x) {
815 return bool(x) ? v < *x : false;
816}
817
818template <class T>
819constexpr bool operator>=(const optional<T&>& x, const T& v) {
820 return bool(x) ? *x >= v : false;
821}
822
823template <class T>
824constexpr bool operator<=(const T& v, const optional<T&>& x) {
825 return bool(x) ? v <= *x : false;
826}
827
828template <class T>
829constexpr bool operator<=(const optional<T&>& x, const T& v) {
830 return bool(x) ? *x <= v : true;
831}
832
833template <class T>
834constexpr bool operator>=(const T& v, const optional<T&>& x) {
835 return bool(x) ? v >= *x : true;
836}
837
838// Comparison of optional<T const&> with T
839template <class T>
840constexpr bool operator==(const optional<const T&>& x, const T& v) {
841 return bool(x) ? *x == v : false;
842}
843
844template <class T>
845constexpr bool operator==(const T& v, const optional<const T&>& x) {
846 return bool(x) ? v == *x : false;
847}
848
849template <class T>
850constexpr bool operator!=(const optional<const T&>& x, const T& v) {
851 return bool(x) ? *x != v : true;
852}
853
854template <class T>
855constexpr bool operator!=(const T& v, const optional<const T&>& x) {
856 return bool(x) ? v != *x : true;
857}
858
859template <class T>
860constexpr bool operator<(const optional<const T&>& x, const T& v) {
861 return bool(x) ? *x < v : true;
862}
863
864template <class T>
865constexpr bool operator>(const T& v, const optional<const T&>& x) {
866 return bool(x) ? v > *x : true;
867}
868
869template <class T>
870constexpr bool operator>(const optional<const T&>& x, const T& v) {
871 return bool(x) ? *x > v : false;
872}
873
874template <class T>
875constexpr bool operator<(const T& v, const optional<const T&>& x) {
876 return bool(x) ? v < *x : false;
877}
878
879template <class T>
880constexpr bool operator>=(const optional<const T&>& x, const T& v) {
881 return bool(x) ? *x >= v : false;
882}
883
884template <class T>
885constexpr bool operator<=(const T& v, const optional<const T&>& x) {
886 return bool(x) ? v <= *x : false;
887}
888
889template <class T>
890constexpr bool operator<=(const optional<const T&>& x, const T& v) {
891 return bool(x) ? *x <= v : true;
892}
893
894template <class T>
895constexpr bool operator>=(const T& v, const optional<const T&>& x) {
896 return bool(x) ? v >= *x : true;
897}
898
899// 20.5.12, Specialized algorithms
900template <class T>
901void swap(optional<T>& x, optional<T>& y) noexcept(noexcept(x.swap(y))) {
902 x.swap(y);
903}
904
905template <class T>
907 return optional<typename std::decay<T>::type>(constexpr_forward<T>(v));
908}
909
910template <class X>
911constexpr optional<X&> make_optional(std::reference_wrapper<X> v) {
912 return optional<X&>(v.get());
913}
914
915} // namespace utility
916} // namespace open3d
917
918namespace std {
919template <typename T>
920struct hash<open3d::utility::optional<T>> {
921 typedef typename hash<T>::result_type result_type;
922 typedef open3d::utility::optional<T> argument_type;
923
924 constexpr result_type operator()(argument_type const& arg) const {
925 return arg ? std::hash<T>{}(*arg) : result_type{};
926 }
927};
928
929template <typename T>
930struct hash<open3d::utility::optional<T&>> {
931 typedef typename hash<T>::result_type result_type;
932 typedef open3d::utility::optional<T&> argument_type;
933
934 constexpr result_type operator()(argument_type const& arg) const {
935 return arg ? std::hash<T>{}(*arg) : result_type{};
936 }
937};
938} // namespace std
939
940#undef TR2_OPTIONAL_REQUIRES
941#undef TR2_OPTIONAL_ASSERTED_EXPRESSION
942#undef TR2_OPTIONAL_HOST_CONSTEXPR
#define TR2_OPTIONAL_REQUIRES(...)
Definition Optional.h:46
#define TR2_OPTIONAL_HOST_CONSTEXPR
Definition Optional.h:96
#define TR2_OPTIONAL_ASSERTED_EXPRESSION(CHECK, EXPR)
Definition Optional.h:89
double t
Definition SurfaceReconstructionPoisson.cpp:172
Definition Optional.h:155
bad_optional_access(const char *what_arg)
Definition Optional.h:159
bad_optional_access(const std::string &what_arg)
Definition Optional.h:157
auto operator=(U &&rhs) noexcept -> typename std::enable_if< !std::is_same< typename std::decay< U >::type, optional< T & > >::value, optional & >::type=delete
constexpr optional(U &u) noexcept
Definition Optional.h:541
constexpr optional() noexcept
Definition Optional.h:536
auto operator=(U &&rhs) noexcept -> typename std::enable_if< std::is_same< typename std::decay< U >::type, optional< T & > >::value, optional & >::type
Definition Optional.h:572
optional & operator=(nullopt_t) noexcept
Definition Optional.h:556
void reset() noexcept
Definition Optional.h:616
constexpr optional(nullopt_t) noexcept
Definition Optional.h:538
void emplace(T &v) noexcept
Definition Optional.h:584
constexpr T & value() const
Definition Optional.h:599
optional(in_place_t, T &&)=delete
TR2_OPTIONAL_HOST_CONSTEXPR T & operator*() const
Definition Optional.h:595
void swap(optional< T & > &rhs) noexcept
Definition Optional.h:588
constexpr optional(in_place_t, T &v) noexcept
Definition Optional.h:548
TR2_OPTIONAL_HOST_CONSTEXPR T * operator->() const
Definition Optional.h:591
constexpr bool has_value() const noexcept
Definition Optional.h:606
constexpr std::decay< T >::type value_or(V &&v) const
Definition Optional.h:609
constexpr optional(const optional &rhs) noexcept
Definition Optional.h:546
Definition Optional.h:259
TR2_OPTIONAL_HOST_CONSTEXPR T & operator*() &
Definition Optional.h:468
constexpr bool has_value() const noexcept
Definition Optional.h:453
optional(const optional &rhs)
Definition Optional.h:320
T value_type
Definition Optional.h:314
constexpr T value_or(V &&v) const &
Definition Optional.h:498
constexpr optional() noexcept
Definition Optional.h:317
void emplace(std::initializer_list< U > il, Args &&... args)
Definition Optional.h:429
constexpr optional(U &&u)
Definition Optional.h:349
constexpr T value_or(V &&v) &&
Definition Optional.h:503
void emplace(Args &&... args)
Definition Optional.h:423
optional & operator=(const optional &rhs)
Definition Optional.h:383
TR2_OPTIONAL_HOST_CONSTEXPR T && value() &&
Definition Optional.h:492
void reset() noexcept
Definition Optional.h:510
auto operator=(U &&v) -> typename std::enable_if< std::is_constructible< T, U >::value &&!std::is_same< typename std::decay< U >::type, optional< T > >::value &&(std::is_scalar< T >::value||std::is_same< typename std::decay< U >::type, T >::value) &&std::is_assignable< T &, U >::value, optional & >::type
Definition Optional.h:406
TR2_OPTIONAL_HOST_CONSTEXPR T const & operator*() const &
Definition Optional.h:464
constexpr optional(in_place_t, std::initializer_list< U > il, Args &&... args)
Definition Optional.h:369
optional(optional &&rhs) noexcept(std::is_nothrow_move_constructible< T >::value)
Definition Optional.h:327
constexpr optional(in_place_t, Args &&... args)
Definition Optional.h:362
void swap(optional< T > &rhs) noexcept(std::is_nothrow_move_constructible< T >::value &&noexcept(std::swap(std::declval< T & >(), std::declval< T & >())))
Definition Optional.h:435
TR2_OPTIONAL_HOST_CONSTEXPR T && operator*() &&
Definition Optional.h:473
optional & operator=(optional &&rhs) noexcept(std::is_nothrow_move_assignable< T >::value &&std::is_nothrow_move_constructible< T >::value)
Definition Optional.h:393
TR2_OPTIONAL_HOST_CONSTEXPR T & value() &
Definition Optional.h:485
TR2_OPTIONAL_HOST_CONSTEXPR T const * operator->() const
Definition Optional.h:455
optional & operator=(nullopt_t) noexcept
Definition Optional.h:378
constexpr optional(nullopt_t) noexcept
Definition Optional.h:318
TR2_OPTIONAL_HOST_CONSTEXPR T * operator->()
Definition Optional.h:459
TR2_OPTIONAL_HOST_CONSTEXPR T const & value() const &
Definition Optional.h:478
char type
Definition FilePCD.cpp:41
constexpr U convert(U v)
Definition Optional.h:138
constexpr T * static_addressof(T &ref)
Definition Optional.h:125
constexpr std::remove_reference< T >::type && constexpr_move(T &&t) noexcept
Definition Optional.h:81
constexpr in_place_t in_place
Definition Optional.h:56
constexpr struct open3d::utility::trivial_init_t trivial_init
constexpr bool operator<(const optional< T > &x, const optional< T > &y)
Definition Optional.h:636
constexpr T && constexpr_forward(typename std::remove_reference< T >::type &t) noexcept
Definition Optional.h:68
constexpr optional< typename std::decay< T >::type > make_optional(T &&v)
Definition Optional.h:906
constexpr bool operator>=(const optional< T > &x, const optional< T > &y)
Definition Optional.h:651
constexpr bool operator==(const optional< T > &x, const optional< T > &y)
Definition Optional.h:626
typename std::conditional< std::is_trivially_destructible< T >::value, constexpr_optional_base< typename std::remove_const< T >::type >, optional_base< typename std::remove_const< T >::type > >::type OptionalBase
Definition Optional.h:256
void swap(optional< T > &x, optional< T > &y) noexcept(noexcept(x.swap(y)))
Definition Optional.h:901
constexpr bool operator<=(const optional< T > &x, const optional< T > &y)
Definition Optional.h:646
constexpr bool operator>(const optional< T > &x, const optional< T > &y)
Definition Optional.h:641
constexpr nullopt_t nullopt
Definition Optional.h:152
constexpr bool operator!=(const optional< T > &x, const optional< T > &y)
Definition Optional.h:631
Definition PinholeCameraIntrinsic.cpp:16
Definition Device.h:111
void swap(open3d::core::SmallVectorImpl< T > &LHS, open3d::core::SmallVectorImpl< T > &RHS)
Implement std::swap in terms of SmallVector swap.
Definition SmallVector.h:1370
constexpr constexpr_optional_base() noexcept
Definition Optional.h:226
constexpr_storage_t< T > storage_
Definition Optional.h:224
constexpr constexpr_optional_base(in_place_t, Args &&... args)
Definition Optional.h:236
constexpr constexpr_optional_base(T &&v)
Definition Optional.h:232
bool init_
Definition Optional.h:223
constexpr constexpr_optional_base(in_place_t, std::initializer_list< U > il, Args &&... args)
Definition Optional.h:243
constexpr constexpr_optional_base(const T &v)
Definition Optional.h:229
static constexpr bool value
Definition Optional.h:121
static constexpr bool has_overload(bool)
Definition Optional.h:117
static constexpr bool has_overload(...)
Definition Optional.h:112
Definition Optional.h:52
Definition Optional.h:149
Definition Optional.h:148
constexpr nullopt_t(init)
Definition Optional.h:150
Definition Optional.h:192
~optional_base()
Definition Optional.h:216
bool init_
Definition Optional.h:193
optional_base(in_place_t, std::initializer_list< U > il, Args &&... args)
Definition Optional.h:211
storage_t< T > storage_
Definition Optional.h:194
optional_base(in_place_t, Args &&... args)
Definition Optional.h:204
constexpr optional_base(const T &v)
Definition Optional.h:198
constexpr optional_base() noexcept
Definition Optional.h:196
constexpr optional_base(T &&v)
Definition Optional.h:200
Definition Optional.h:144
Definition Optional.h:178
T value_
Definition Optional.h:180
constexpr constexpr_storage_t(trivial_init_t) noexcept
Definition Optional.h:182
unsigned char dummy_
Definition Optional.h:179
constexpr constexpr_storage_t(Args &&... args)
Definition Optional.h:185
Definition Optional.h:164
constexpr storage_t(Args &&... args)
Definition Optional.h:171
unsigned char dummy_
Definition Optional.h:165
constexpr storage_t(trivial_init_t) noexcept
Definition Optional.h:168
~storage_t()
Definition Optional.h:174
T value_
Definition Optional.h:166