comparison dep/toml11/toml/get.hpp @ 318:3b355fa948c7

config: use TOML instead of INI unfortunately, INI is not enough, and causes some paths including semicolons to break with our current storage of the library folders. so, I decided to switch to TOML which does support real arrays...
author Paper <paper@paper.us.eu.org>
date Wed, 12 Jun 2024 05:25:41 -0400
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317:b1f4d1867ab1 318:3b355fa948c7
1 // Copyright Toru Niina 2017.
2 // Distributed under the MIT License.
3 #ifndef TOML11_GET_HPP
4 #define TOML11_GET_HPP
5 #include <algorithm>
6
7 #include "from.hpp"
8 #include "result.hpp"
9 #include "value.hpp"
10
11 namespace toml
12 {
13
14 // ============================================================================
15 // exact toml::* type
16
17 template<typename T, typename C,
18 template<typename ...> class M, template<typename ...> class V>
19 detail::enable_if_t<detail::is_exact_toml_type<T, basic_value<C, M, V>>::value, T> &
20 get(basic_value<C, M, V>& v)
21 {
22 return v.template cast<detail::type_to_enum<T, basic_value<C, M, V>>::value>();
23 }
24
25 template<typename T, typename C,
26 template<typename ...> class M, template<typename ...> class V>
27 detail::enable_if_t<detail::is_exact_toml_type<T, basic_value<C, M, V>>::value, T> const&
28 get(const basic_value<C, M, V>& v)
29 {
30 return v.template cast<detail::type_to_enum<T, basic_value<C, M, V>>::value>();
31 }
32
33 template<typename T, typename C,
34 template<typename ...> class M, template<typename ...> class V>
35 detail::enable_if_t<detail::is_exact_toml_type<T, basic_value<C, M, V>>::value, T>
36 get(basic_value<C, M, V>&& v)
37 {
38 return T(std::move(v).template cast<detail::type_to_enum<T, basic_value<C, M, V>>::value>());
39 }
40
41 // ============================================================================
42 // T == toml::value; identity transformation.
43
44 template<typename T, typename C,
45 template<typename ...> class M, template<typename ...> class V>
46 inline detail::enable_if_t<std::is_same<T, basic_value<C, M, V>>::value, T>&
47 get(basic_value<C, M, V>& v)
48 {
49 return v;
50 }
51
52 template<typename T, typename C,
53 template<typename ...> class M, template<typename ...> class V>
54 inline detail::enable_if_t<std::is_same<T, basic_value<C, M, V>>::value, T> const&
55 get(const basic_value<C, M, V>& v)
56 {
57 return v;
58 }
59
60 template<typename T, typename C,
61 template<typename ...> class M, template<typename ...> class V>
62 inline detail::enable_if_t<std::is_same<T, basic_value<C, M, V>>::value, T>
63 get(basic_value<C, M, V>&& v)
64 {
65 return basic_value<C, M, V>(std::move(v));
66 }
67
68 // ============================================================================
69 // T == toml::basic_value<C2, M2, V2>; basic_value -> basic_value
70
71 template<typename T, typename C,
72 template<typename ...> class M, template<typename ...> class V>
73 inline detail::enable_if_t<detail::conjunction<detail::is_basic_value<T>,
74 detail::negation<std::is_same<T, basic_value<C, M, V>>>
75 >::value, T>
76 get(const basic_value<C, M, V>& v)
77 {
78 return T(v);
79 }
80
81 // ============================================================================
82 // integer convertible from toml::Integer
83
84 template<typename T, typename C,
85 template<typename ...> class M, template<typename ...> class V>
86 inline detail::enable_if_t<detail::conjunction<
87 std::is_integral<T>, // T is integral
88 detail::negation<std::is_same<T, bool>>, // but not bool
89 detail::negation< // but not toml::integer
90 detail::is_exact_toml_type<T, basic_value<C, M, V>>>
91 >::value, T>
92 get(const basic_value<C, M, V>& v)
93 {
94 return static_cast<T>(v.as_integer());
95 }
96
97 // ============================================================================
98 // floating point convertible from toml::Float
99
100 template<typename T, typename C,
101 template<typename ...> class M, template<typename ...> class V>
102 inline detail::enable_if_t<detail::conjunction<
103 std::is_floating_point<T>, // T is floating_point
104 detail::negation< // but not toml::floating
105 detail::is_exact_toml_type<T, basic_value<C, M, V>>>
106 >::value, T>
107 get(const basic_value<C, M, V>& v)
108 {
109 return static_cast<T>(v.as_floating());
110 }
111
112 // ============================================================================
113 // std::string; toml uses its own toml::string, but it should be convertible to
114 // std::string seamlessly
115
116 template<typename T, typename C,
117 template<typename ...> class M, template<typename ...> class V>
118 inline detail::enable_if_t<std::is_same<T, std::string>::value, std::string>&
119 get(basic_value<C, M, V>& v)
120 {
121 return v.as_string().str;
122 }
123
124 template<typename T, typename C,
125 template<typename ...> class M, template<typename ...> class V>
126 inline detail::enable_if_t<std::is_same<T, std::string>::value, std::string> const&
127 get(const basic_value<C, M, V>& v)
128 {
129 return v.as_string().str;
130 }
131
132 template<typename T, typename C,
133 template<typename ...> class M, template<typename ...> class V>
134 inline detail::enable_if_t<std::is_same<T, std::string>::value, std::string>
135 get(basic_value<C, M, V>&& v)
136 {
137 return std::string(std::move(v.as_string().str));
138 }
139
140 // ============================================================================
141 // std::string_view
142
143 #if defined(TOML11_USING_STRING_VIEW) && TOML11_USING_STRING_VIEW>0
144 template<typename T, typename C,
145 template<typename ...> class M, template<typename ...> class V>
146 inline detail::enable_if_t<std::is_same<T, std::string_view>::value, std::string_view>
147 get(const basic_value<C, M, V>& v)
148 {
149 return std::string_view(v.as_string().str);
150 }
151 #endif
152
153 // ============================================================================
154 // std::chrono::duration from toml::local_time.
155
156 template<typename T, typename C,
157 template<typename ...> class M, template<typename ...> class V>
158 inline detail::enable_if_t<detail::is_chrono_duration<T>::value, T>
159 get(const basic_value<C, M, V>& v)
160 {
161 return std::chrono::duration_cast<T>(
162 std::chrono::nanoseconds(v.as_local_time()));
163 }
164
165 // ============================================================================
166 // std::chrono::system_clock::time_point from toml::datetime variants
167
168 template<typename T, typename C,
169 template<typename ...> class M, template<typename ...> class V>
170 inline detail::enable_if_t<
171 std::is_same<std::chrono::system_clock::time_point, T>::value, T>
172 get(const basic_value<C, M, V>& v)
173 {
174 switch(v.type())
175 {
176 case value_t::local_date:
177 {
178 return std::chrono::system_clock::time_point(v.as_local_date());
179 }
180 case value_t::local_datetime:
181 {
182 return std::chrono::system_clock::time_point(v.as_local_datetime());
183 }
184 case value_t::offset_datetime:
185 {
186 return std::chrono::system_clock::time_point(v.as_offset_datetime());
187 }
188 default:
189 {
190 throw type_error(detail::format_underline("toml::value: "
191 "bad_cast to std::chrono::system_clock::time_point", {
192 {v.location(), concat_to_string("the actual type is ", v.type())}
193 }), v.location());
194 }
195 }
196 }
197
198 // ============================================================================
199 // forward declaration to use this recursively. ignore this and go ahead.
200
201 // array-like type with push_back(value) method
202 template<typename T, typename C,
203 template<typename ...> class M, template<typename ...> class V>
204 detail::enable_if_t<detail::conjunction<
205 detail::is_container<T>, // T is a container
206 detail::has_push_back_method<T>, // T::push_back(value) works
207 detail::negation< // but not toml::array
208 detail::is_exact_toml_type<T, basic_value<C, M, V>>>
209 >::value, T>
210 get(const basic_value<C, M, V>&);
211
212 // array-like type without push_back(value) method
213 template<typename T, typename C,
214 template<typename ...> class M, template<typename ...> class V>
215 detail::enable_if_t<detail::conjunction<
216 detail::is_container<T>, // T is a container
217 detail::negation<detail::has_push_back_method<T>>, // w/o push_back(...)
218 detail::negation<detail::has_specialized_from<T>>, // T does not have special conversion
219 detail::negation< // not toml::array
220 detail::is_exact_toml_type<T, basic_value<C, M, V>>>
221 >::value, T>
222 get(const basic_value<C, M, V>&);
223
224 // std::pair<T1, T2>
225 template<typename T, typename C,
226 template<typename ...> class M, template<typename ...> class V>
227 detail::enable_if_t<detail::is_std_pair<T>::value, T>
228 get(const basic_value<C, M, V>&);
229
230 // std::tuple<T1, T2, ...>
231 template<typename T, typename C,
232 template<typename ...> class M, template<typename ...> class V>
233 detail::enable_if_t<detail::is_std_tuple<T>::value, T>
234 get(const basic_value<C, M, V>&);
235
236 // map-like classes
237 template<typename T, typename C,
238 template<typename ...> class M, template<typename ...> class V>
239 detail::enable_if_t<detail::conjunction<
240 detail::is_map<T>, // T is map
241 detail::negation< // but not toml::table
242 detail::is_exact_toml_type<T, basic_value<C, M, V>>>
243 >::value, T>
244 get(const basic_value<C, M, V>&);
245
246 // T.from_toml(v)
247 template<typename T, typename C,
248 template<typename ...> class M, template<typename ...> class V>
249 detail::enable_if_t<detail::conjunction<
250 detail::negation< // not a toml::* type
251 detail::is_exact_toml_type<T, basic_value<C, M, V>>>,
252 detail::has_from_toml_method<T, C, M, V>, // but has from_toml(toml::value)
253 std::is_default_constructible<T> // and default constructible
254 >::value, T>
255 get(const basic_value<C, M, V>&);
256
257 // toml::from<T>::from_toml(v)
258 template<typename T, typename C,
259 template<typename ...> class M, template<typename ...> class V>
260 detail::enable_if_t<detail::has_specialized_from<T>::value, T>
261 get(const basic_value<C, M, V>&);
262
263 template<typename T, typename C,
264 template<typename ...> class M, template<typename ...> class V>
265 detail::enable_if_t<detail::has_specialized_from<T>::value, T>
266 get(basic_value<C, M, V>&);
267
268 // T(const toml::value&) and T is not toml::basic_value,
269 // and it does not have `from<T>` nor `from_toml`.
270 template<typename T, typename C,
271 template<typename ...> class M, template<typename ...> class V>
272 detail::enable_if_t<detail::conjunction<
273 detail::negation<detail::is_basic_value<T>>,
274 std::is_constructible<T, const basic_value<C, M, V>&>,
275 detail::negation<detail::has_from_toml_method<T, C, M, V>>,
276 detail::negation<detail::has_specialized_from<T>>
277 >::value, T>
278 get(const basic_value<C, M, V>&);
279
280 template<typename T, typename C,
281 template<typename ...> class M, template<typename ...> class V>
282 detail::enable_if_t<detail::conjunction<
283 detail::negation<detail::is_basic_value<T>>,
284 std::is_constructible<T, basic_value<C, M, V>&>,
285 detail::negation<detail::has_from_toml_method<T, C, M, V>>,
286 detail::negation<detail::has_specialized_from<T>>
287 >::value, T>
288 get(basic_value<C, M, V>&);
289
290 // ============================================================================
291 // array-like types; most likely STL container, like std::vector, etc.
292
293 template<typename T, typename C,
294 template<typename ...> class M, template<typename ...> class V>
295 detail::enable_if_t<detail::conjunction<
296 detail::is_container<T>, // T is a container
297 detail::has_push_back_method<T>, // container.push_back(elem) works
298 detail::negation< // but not toml::array
299 detail::is_exact_toml_type<T, basic_value<C, M, V>>>
300 >::value, T>
301 get(const basic_value<C, M, V>& v)
302 {
303 using value_type = typename T::value_type;
304 const auto& ary = v.as_array();
305
306 T container;
307 try_reserve(container, ary.size());
308
309 for(const auto& elem : ary)
310 {
311 container.push_back(get<value_type>(elem));
312 }
313 return container;
314 }
315
316 // ============================================================================
317 // std::forward_list does not have push_back, insert, or emplace.
318 // It has insert_after, emplace_after, push_front.
319
320 template<typename T, typename C,
321 template<typename ...> class M, template<typename ...> class V>
322 detail::enable_if_t<detail::is_std_forward_list<T>::value, T>
323 get(const basic_value<C, M, V>& v)
324 {
325 using value_type = typename T::value_type;
326 T container;
327 for(const auto& elem : v.as_array())
328 {
329 container.push_front(get<value_type>(elem));
330 }
331 container.reverse();
332 return container;
333 }
334
335 // ============================================================================
336 // array-like types, without push_back(). most likely [std|boost]::array.
337
338 template<typename T, typename C,
339 template<typename ...> class M, template<typename ...> class V>
340 detail::enable_if_t<detail::conjunction<
341 detail::is_container<T>, // T is a container
342 detail::negation<detail::has_push_back_method<T>>, // w/o push_back
343 detail::negation<detail::has_specialized_from<T>>, // T does not have special conversion
344 detail::negation< // T is not toml::array
345 detail::is_exact_toml_type<T, basic_value<C, M, V>>>
346 >::value, T>
347 get(const basic_value<C, M, V>& v)
348 {
349 using value_type = typename T::value_type;
350 const auto& ar = v.as_array();
351
352 T container;
353 if(ar.size() != container.size())
354 {
355 throw std::out_of_range(detail::format_underline(concat_to_string(
356 "toml::get: specified container size is ", container.size(),
357 " but there are ", ar.size(), " elements in toml array."), {
358 {v.location(), "here"}
359 }));
360 }
361 for(std::size_t i=0; i<ar.size(); ++i)
362 {
363 container[i] = ::toml::get<value_type>(ar[i]);
364 }
365 return container;
366 }
367
368 // ============================================================================
369 // std::pair.
370
371 template<typename T, typename C,
372 template<typename ...> class M, template<typename ...> class V>
373 detail::enable_if_t<detail::is_std_pair<T>::value, T>
374 get(const basic_value<C, M, V>& v)
375 {
376 using first_type = typename T::first_type;
377 using second_type = typename T::second_type;
378
379 const auto& ar = v.as_array();
380 if(ar.size() != 2)
381 {
382 throw std::out_of_range(detail::format_underline(concat_to_string(
383 "toml::get: specified std::pair but there are ", ar.size(),
384 " elements in toml array."), {{v.location(), "here"}}));
385 }
386 return std::make_pair(::toml::get<first_type >(ar.at(0)),
387 ::toml::get<second_type>(ar.at(1)));
388 }
389
390 // ============================================================================
391 // std::tuple.
392
393 namespace detail
394 {
395 template<typename T, typename Array, std::size_t ... I>
396 T get_tuple_impl(const Array& a, index_sequence<I...>)
397 {
398 return std::make_tuple(
399 ::toml::get<typename std::tuple_element<I, T>::type>(a.at(I))...);
400 }
401 } // detail
402
403 template<typename T, typename C,
404 template<typename ...> class M, template<typename ...> class V>
405 detail::enable_if_t<detail::is_std_tuple<T>::value, T>
406 get(const basic_value<C, M, V>& v)
407 {
408 const auto& ar = v.as_array();
409 if(ar.size() != std::tuple_size<T>::value)
410 {
411 throw std::out_of_range(detail::format_underline(concat_to_string(
412 "toml::get: specified std::tuple with ",
413 std::tuple_size<T>::value, " elements, but there are ", ar.size(),
414 " elements in toml array."), {{v.location(), "here"}}));
415 }
416 return detail::get_tuple_impl<T>(ar,
417 detail::make_index_sequence<std::tuple_size<T>::value>{});
418 }
419
420 // ============================================================================
421 // map-like types; most likely STL map, like std::map or std::unordered_map.
422
423 template<typename T, typename C,
424 template<typename ...> class M, template<typename ...> class V>
425 detail::enable_if_t<detail::conjunction<
426 detail::is_map<T>, // T is map
427 detail::negation< // but not toml::array
428 detail::is_exact_toml_type<T, basic_value<C, M, V>>>
429 >::value, T>
430 get(const basic_value<C, M, V>& v)
431 {
432 using key_type = typename T::key_type;
433 using mapped_type = typename T::mapped_type;
434 static_assert(std::is_convertible<std::string, key_type>::value,
435 "toml::get only supports map type of which key_type is "
436 "convertible from std::string.");
437 T map;
438 for(const auto& kv : v.as_table())
439 {
440 map.emplace(key_type(kv.first), get<mapped_type>(kv.second));
441 }
442 return map;
443 }
444
445 // ============================================================================
446 // user-defined, but compatible types.
447
448 template<typename T, typename C,
449 template<typename ...> class M, template<typename ...> class V>
450 detail::enable_if_t<detail::conjunction<
451 detail::negation< // not a toml::* type
452 detail::is_exact_toml_type<T, basic_value<C, M, V>>>,
453 detail::has_from_toml_method<T, C, M, V>, // but has from_toml(toml::value) memfn
454 std::is_default_constructible<T> // and default constructible
455 >::value, T>
456 get(const basic_value<C, M, V>& v)
457 {
458 T ud;
459 ud.from_toml(v);
460 return ud;
461 }
462 template<typename T, typename C,
463 template<typename ...> class M, template<typename ...> class V>
464 detail::enable_if_t<detail::has_specialized_from<T>::value, T>
465 get(const basic_value<C, M, V>& v)
466 {
467 return ::toml::from<T>::from_toml(v);
468 }
469 template<typename T, typename C,
470 template<typename ...> class M, template<typename ...> class V>
471 detail::enable_if_t<detail::has_specialized_from<T>::value, T>
472 get(basic_value<C, M, V>& v)
473 {
474 return ::toml::from<T>::from_toml(v);
475 }
476
477 template<typename T, typename C,
478 template<typename ...> class M, template<typename ...> class V>
479 detail::enable_if_t<detail::conjunction<
480 detail::negation<detail::is_basic_value<T>>, // T is not a toml::value
481 std::is_constructible<T, const basic_value<C, M, V>&>, // T is constructible from toml::value
482 detail::negation<detail::has_from_toml_method<T, C, M, V>>, // and T does not have T.from_toml(v);
483 detail::negation<detail::has_specialized_from<T>> // and T does not have toml::from<T>{};
484 >::value, T>
485 get(const basic_value<C, M, V>& v)
486 {
487 return T(v);
488 }
489
490 template<typename T, typename C,
491 template<typename ...> class M, template<typename ...> class V>
492 detail::enable_if_t<detail::conjunction<
493 detail::negation<detail::is_basic_value<T>>, // T is not a toml::value
494 std::is_constructible<T, basic_value<C, M, V>&>, // T is constructible from toml::value
495 detail::negation<detail::has_from_toml_method<T, C, M, V>>, // and T does not have T.from_toml(v);
496 detail::negation<detail::has_specialized_from<T>> // and T does not have toml::from<T>{};
497 >::value, T>
498 get(basic_value<C, M, V>& v)
499 {
500 return T(v);
501 }
502
503 // ============================================================================
504 // find
505
506 // ----------------------------------------------------------------------------
507 // these overloads do not require to set T. and returns value itself.
508 template<typename C,
509 template<typename ...> class M, template<typename ...> class V>
510 basic_value<C, M, V> const& find(const basic_value<C, M, V>& v, const key& ky)
511 {
512 const auto& tab = v.as_table();
513 if(tab.count(ky) == 0)
514 {
515 detail::throw_key_not_found_error(v, ky);
516 }
517 return tab.at(ky);
518 }
519 template<typename C,
520 template<typename ...> class M, template<typename ...> class V>
521 basic_value<C, M, V>& find(basic_value<C, M, V>& v, const key& ky)
522 {
523 auto& tab = v.as_table();
524 if(tab.count(ky) == 0)
525 {
526 detail::throw_key_not_found_error(v, ky);
527 }
528 return tab.at(ky);
529 }
530 template<typename C,
531 template<typename ...> class M, template<typename ...> class V>
532 basic_value<C, M, V> find(basic_value<C, M, V>&& v, const key& ky)
533 {
534 typename basic_value<C, M, V>::table_type tab = std::move(v).as_table();
535 if(tab.count(ky) == 0)
536 {
537 detail::throw_key_not_found_error(v, ky);
538 }
539 return basic_value<C, M, V>(std::move(tab.at(ky)));
540 }
541
542 // ----------------------------------------------------------------------------
543 // find(value, idx)
544 template<typename C,
545 template<typename ...> class M, template<typename ...> class V>
546 basic_value<C, M, V> const&
547 find(const basic_value<C, M, V>& v, const std::size_t idx)
548 {
549 const auto& ary = v.as_array();
550 if(ary.size() <= idx)
551 {
552 throw std::out_of_range(detail::format_underline(concat_to_string(
553 "index ", idx, " is out of range"), {{v.location(), "in this array"}}));
554 }
555 return ary.at(idx);
556 }
557 template<typename C,
558 template<typename ...> class M, template<typename ...> class V>
559 basic_value<C, M, V>& find(basic_value<C, M, V>& v, const std::size_t idx)
560 {
561 auto& ary = v.as_array();
562 if(ary.size() <= idx)
563 {
564 throw std::out_of_range(detail::format_underline(concat_to_string(
565 "index ", idx, " is out of range"), {{v.location(), "in this array"}}));
566 }
567 return ary.at(idx);
568 }
569 template<typename C,
570 template<typename ...> class M, template<typename ...> class V>
571 basic_value<C, M, V> find(basic_value<C, M, V>&& v, const std::size_t idx)
572 {
573 auto& ary = v.as_array();
574 if(ary.size() <= idx)
575 {
576 throw std::out_of_range(detail::format_underline(concat_to_string(
577 "index ", idx, " is out of range"), {{v.location(), "in this array"}}));
578 }
579 return basic_value<C, M, V>(std::move(ary.at(idx)));
580 }
581
582 // ----------------------------------------------------------------------------
583 // find<T>(value, key);
584
585 template<typename T, typename C,
586 template<typename ...> class M, template<typename ...> class V>
587 decltype(::toml::get<T>(std::declval<basic_value<C, M, V> const&>()))
588 find(const basic_value<C, M, V>& v, const key& ky)
589 {
590 const auto& tab = v.as_table();
591 if(tab.count(ky) == 0)
592 {
593 detail::throw_key_not_found_error(v, ky);
594 }
595 return ::toml::get<T>(tab.at(ky));
596 }
597
598 template<typename T, typename C,
599 template<typename ...> class M, template<typename ...> class V>
600 decltype(::toml::get<T>(std::declval<basic_value<C, M, V>&>()))
601 find(basic_value<C, M, V>& v, const key& ky)
602 {
603 auto& tab = v.as_table();
604 if(tab.count(ky) == 0)
605 {
606 detail::throw_key_not_found_error(v, ky);
607 }
608 return ::toml::get<T>(tab.at(ky));
609 }
610
611 template<typename T, typename C,
612 template<typename ...> class M, template<typename ...> class V>
613 decltype(::toml::get<T>(std::declval<basic_value<C, M, V>&&>()))
614 find(basic_value<C, M, V>&& v, const key& ky)
615 {
616 typename basic_value<C, M, V>::table_type tab = std::move(v).as_table();
617 if(tab.count(ky) == 0)
618 {
619 detail::throw_key_not_found_error(v, ky);
620 }
621 return ::toml::get<T>(std::move(tab.at(ky)));
622 }
623
624 // ----------------------------------------------------------------------------
625 // find<T>(value, idx)
626 template<typename T, typename C,
627 template<typename ...> class M, template<typename ...> class V>
628 decltype(::toml::get<T>(std::declval<basic_value<C, M, V> const&>()))
629 find(const basic_value<C, M, V>& v, const std::size_t idx)
630 {
631 const auto& ary = v.as_array();
632 if(ary.size() <= idx)
633 {
634 throw std::out_of_range(detail::format_underline(concat_to_string(
635 "index ", idx, " is out of range"), {{v.location(), "in this array"}}));
636 }
637 return ::toml::get<T>(ary.at(idx));
638 }
639 template<typename T, typename C,
640 template<typename ...> class M, template<typename ...> class V>
641 decltype(::toml::get<T>(std::declval<basic_value<C, M, V>&>()))
642 find(basic_value<C, M, V>& v, const std::size_t idx)
643 {
644 auto& ary = v.as_array();
645 if(ary.size() <= idx)
646 {
647 throw std::out_of_range(detail::format_underline(concat_to_string(
648 "index ", idx, " is out of range"), {{v.location(), "in this array"}}));
649 }
650 return ::toml::get<T>(ary.at(idx));
651 }
652 template<typename T, typename C,
653 template<typename ...> class M, template<typename ...> class V>
654 decltype(::toml::get<T>(std::declval<basic_value<C, M, V>&&>()))
655 find(basic_value<C, M, V>&& v, const std::size_t idx)
656 {
657 typename basic_value<C, M, V>::array_type ary = std::move(v).as_array();
658 if(ary.size() <= idx)
659 {
660 throw std::out_of_range(detail::format_underline(concat_to_string(
661 "index ", idx, " is out of range"), {{v.location(), "in this array"}}));
662 }
663 return ::toml::get<T>(std::move(ary.at(idx)));
664 }
665
666 // --------------------------------------------------------------------------
667 // toml::find(toml::value, toml::key, Ts&& ... keys)
668
669 namespace detail
670 {
671 // It suppresses warnings by -Wsign-conversion. Let's say we have the following
672 // code.
673 // ```cpp
674 // const auto x = toml::find<std::string>(data, "array", 0);
675 // ```
676 // Here, the type of literal number `0` is `int`. `int` is a signed integer.
677 // `toml::find` takes `std::size_t` as an index. So it causes implicit sign
678 // conversion and `-Wsign-conversion` warns about it. Using `0u` instead of `0`
679 // suppresses the warning, but it makes user code messy.
680 // To suppress this warning, we need to be aware of type conversion caused
681 // by `toml::find(v, key1, key2, ... keys)`. But the thing is that the types of
682 // keys can be any combination of {string-like, size_t-like}. Of course we can't
683 // write down all the combinations. Thus we need to use some function that
684 // recognize the type of argument and cast it into `std::string` or
685 // `std::size_t` depending on the context.
686 // `key_cast` does the job. It has 2 overloads. One is invoked when the
687 // argument type is an integer and cast the argument into `std::size_t`. The
688 // other is invoked when the argument type is not an integer, possibly one of
689 // std::string, const char[N] or const char*, and construct std::string from
690 // the argument.
691 // `toml::find(v, k1, k2, ... ks)` uses `key_cast` before passing `ks` to
692 // `toml::find(v, k)` to suppress -Wsign-conversion.
693
694 template<typename T>
695 enable_if_t<conjunction<std::is_integral<remove_cvref_t<T>>,
696 negation<std::is_same<remove_cvref_t<T>, bool>>>::value, std::size_t>
697 key_cast(T&& v) noexcept
698 {
699 return std::size_t(v);
700 }
701 template<typename T>
702 enable_if_t<negation<conjunction<std::is_integral<remove_cvref_t<T>>,
703 negation<std::is_same<remove_cvref_t<T>, bool>>>>::value, std::string>
704 key_cast(T&& v) noexcept
705 {
706 return std::string(std::forward<T>(v));
707 }
708 } // detail
709
710 template<typename C,
711 template<typename ...> class M, template<typename ...> class V,
712 typename Key1, typename Key2, typename ... Keys>
713 const basic_value<C, M, V>&
714 find(const basic_value<C, M, V>& v, Key1&& k1, Key2&& k2, Keys&& ... keys)
715 {
716 return ::toml::find(::toml::find(v, detail::key_cast(k1)),
717 detail::key_cast(k2), std::forward<Keys>(keys)...);
718 }
719 template<typename C,
720 template<typename ...> class M, template<typename ...> class V,
721 typename Key1, typename Key2, typename ... Keys>
722 basic_value<C, M, V>&
723 find(basic_value<C, M, V>& v, Key1&& k1, Key2&& k2, Keys&& ... keys)
724 {
725 return ::toml::find(::toml::find(v, detail::key_cast(k1)),
726 detail::key_cast(k2), std::forward<Keys>(keys)...);
727 }
728 template<typename C,
729 template<typename ...> class M, template<typename ...> class V,
730 typename Key1, typename Key2, typename ... Keys>
731 basic_value<C, M, V>
732 find(basic_value<C, M, V>&& v, Key1&& k1, Key2&& k2, Keys&& ... keys)
733 {
734 return ::toml::find(::toml::find(std::move(v), std::forward<Key1>(k1)),
735 detail::key_cast(k2), std::forward<Keys>(keys)...);
736 }
737
738 template<typename T, typename C,
739 template<typename ...> class M, template<typename ...> class V,
740 typename Key1, typename Key2, typename ... Keys>
741 decltype(::toml::get<T>(std::declval<const basic_value<C, M, V>&>()))
742 find(const basic_value<C, M, V>& v, Key1&& k1, Key2&& k2, Keys&& ... keys)
743 {
744 return ::toml::find<T>(::toml::find(v, detail::key_cast(k1)),
745 detail::key_cast(k2), std::forward<Keys>(keys)...);
746 }
747 template<typename T, typename C,
748 template<typename ...> class M, template<typename ...> class V,
749 typename Key1, typename Key2, typename ... Keys>
750 decltype(::toml::get<T>(std::declval<basic_value<C, M, V>&>()))
751 find(basic_value<C, M, V>& v, Key1&& k1, Key2&& k2, Keys&& ... keys)
752 {
753 return ::toml::find<T>(::toml::find(v, detail::key_cast(k1)),
754 detail::key_cast(k2), std::forward<Keys>(keys)...);
755 }
756 template<typename T, typename C,
757 template<typename ...> class M, template<typename ...> class V,
758 typename Key1, typename Key2, typename ... Keys>
759 decltype(::toml::get<T>(std::declval<basic_value<C, M, V>&&>()))
760 find(basic_value<C, M, V>&& v, Key1&& k1, Key2&& k2, Keys&& ... keys)
761 {
762 return ::toml::find<T>(::toml::find(std::move(v), detail::key_cast(k1)),
763 detail::key_cast(k2), std::forward<Keys>(keys)...);
764 }
765
766 // ============================================================================
767 // get_or(value, fallback)
768
769 template<typename C,
770 template<typename ...> class M, template<typename ...> class V>
771 basic_value<C, M, V> const&
772 get_or(const basic_value<C, M, V>& v, const basic_value<C, M, V>&)
773 {
774 return v;
775 }
776 template<typename C,
777 template<typename ...> class M, template<typename ...> class V>
778 basic_value<C, M, V>&
779 get_or(basic_value<C, M, V>& v, basic_value<C, M, V>&)
780 {
781 return v;
782 }
783 template<typename C,
784 template<typename ...> class M, template<typename ...> class V>
785 basic_value<C, M, V>
786 get_or(basic_value<C, M, V>&& v, basic_value<C, M, V>&&)
787 {
788 return v;
789 }
790
791 // ----------------------------------------------------------------------------
792 // specialization for the exact toml types (return type becomes lvalue ref)
793
794 template<typename T, typename C,
795 template<typename ...> class M, template<typename ...> class V>
796 detail::enable_if_t<
797 detail::is_exact_toml_type<T, basic_value<C, M, V>>::value, T> const&
798 get_or(const basic_value<C, M, V>& v, const T& opt)
799 {
800 try
801 {
802 return get<detail::remove_cvref_t<T>>(v);
803 }
804 catch(...)
805 {
806 return opt;
807 }
808 }
809 template<typename T, typename C,
810 template<typename ...> class M, template<typename ...> class V>
811 detail::enable_if_t<
812 detail::is_exact_toml_type<T, basic_value<C, M, V>>::value, T>&
813 get_or(basic_value<C, M, V>& v, T& opt)
814 {
815 try
816 {
817 return get<detail::remove_cvref_t<T>>(v);
818 }
819 catch(...)
820 {
821 return opt;
822 }
823 }
824 template<typename T, typename C,
825 template<typename ...> class M, template<typename ...> class V>
826 detail::enable_if_t<detail::is_exact_toml_type<detail::remove_cvref_t<T>,
827 basic_value<C, M, V>>::value, detail::remove_cvref_t<T>>
828 get_or(basic_value<C, M, V>&& v, T&& opt)
829 {
830 try
831 {
832 return get<detail::remove_cvref_t<T>>(std::move(v));
833 }
834 catch(...)
835 {
836 return detail::remove_cvref_t<T>(std::forward<T>(opt));
837 }
838 }
839
840 // ----------------------------------------------------------------------------
841 // specialization for std::string (return type becomes lvalue ref)
842
843 template<typename T, typename C,
844 template<typename ...> class M, template<typename ...> class V>
845 detail::enable_if_t<std::is_same<detail::remove_cvref_t<T>, std::string>::value,
846 std::string> const&
847 get_or(const basic_value<C, M, V>& v, const T& opt)
848 {
849 try
850 {
851 return v.as_string().str;
852 }
853 catch(...)
854 {
855 return opt;
856 }
857 }
858 template<typename T, typename C,
859 template<typename ...> class M, template<typename ...> class V>
860 detail::enable_if_t<std::is_same<T, std::string>::value, std::string>&
861 get_or(basic_value<C, M, V>& v, T& opt)
862 {
863 try
864 {
865 return v.as_string().str;
866 }
867 catch(...)
868 {
869 return opt;
870 }
871 }
872 template<typename T, typename C,
873 template<typename ...> class M, template<typename ...> class V>
874 detail::enable_if_t<
875 std::is_same<detail::remove_cvref_t<T>, std::string>::value, std::string>
876 get_or(basic_value<C, M, V>&& v, T&& opt)
877 {
878 try
879 {
880 return std::move(v.as_string().str);
881 }
882 catch(...)
883 {
884 return std::string(std::forward<T>(opt));
885 }
886 }
887
888 // ----------------------------------------------------------------------------
889 // specialization for string literal
890
891 template<typename T, typename C,
892 template<typename ...> class M, template<typename ...> class V>
893 detail::enable_if_t<detail::is_string_literal<
894 typename std::remove_reference<T>::type>::value, std::string>
895 get_or(const basic_value<C, M, V>& v, T&& opt)
896 {
897 try
898 {
899 return std::move(v.as_string().str);
900 }
901 catch(...)
902 {
903 return std::string(std::forward<T>(opt));
904 }
905 }
906
907 // ----------------------------------------------------------------------------
908 // others (require type conversion and return type cannot be lvalue reference)
909
910 template<typename T, typename C,
911 template<typename ...> class M, template<typename ...> class V>
912 detail::enable_if_t<detail::conjunction<
913 detail::negation<detail::is_exact_toml_type<detail::remove_cvref_t<T>,
914 basic_value<C, M, V>>>,
915 detail::negation<std::is_same<std::string, detail::remove_cvref_t<T>>>,
916 detail::negation<detail::is_string_literal<
917 typename std::remove_reference<T>::type>>
918 >::value, detail::remove_cvref_t<T>>
919 get_or(const basic_value<C, M, V>& v, T&& opt)
920 {
921 try
922 {
923 return get<detail::remove_cvref_t<T>>(v);
924 }
925 catch(...)
926 {
927 return detail::remove_cvref_t<T>(std::forward<T>(opt));
928 }
929 }
930
931 // ===========================================================================
932 // find_or(value, key, fallback)
933
934 template<typename C,
935 template<typename ...> class M, template<typename ...> class V>
936 basic_value<C, M, V> const&
937 find_or(const basic_value<C, M, V>& v, const key& ky,
938 const basic_value<C, M, V>& opt)
939 {
940 if(!v.is_table()) {return opt;}
941 const auto& tab = v.as_table();
942 if(tab.count(ky) == 0) {return opt;}
943 return tab.at(ky);
944 }
945
946 template<typename C,
947 template<typename ...> class M, template<typename ...> class V>
948 basic_value<C, M, V>&
949 find_or(basic_value<C, M, V>& v, const toml::key& ky, basic_value<C, M, V>& opt)
950 {
951 if(!v.is_table()) {return opt;}
952 auto& tab = v.as_table();
953 if(tab.count(ky) == 0) {return opt;}
954 return tab.at(ky);
955 }
956
957 template<typename C,
958 template<typename ...> class M, template<typename ...> class V>
959 basic_value<C, M, V>
960 find_or(basic_value<C, M, V>&& v, const toml::key& ky, basic_value<C, M, V>&& opt)
961 {
962 if(!v.is_table()) {return opt;}
963 auto tab = std::move(v).as_table();
964 if(tab.count(ky) == 0) {return opt;}
965 return basic_value<C, M, V>(std::move(tab.at(ky)));
966 }
967
968 // ---------------------------------------------------------------------------
969 // exact types (return type can be a reference)
970 template<typename T, typename C,
971 template<typename ...> class M, template<typename ...> class V>
972 detail::enable_if_t<
973 detail::is_exact_toml_type<T, basic_value<C, M, V>>::value, T> const&
974 find_or(const basic_value<C, M, V>& v, const key& ky, const T& opt)
975 {
976 if(!v.is_table()) {return opt;}
977 const auto& tab = v.as_table();
978 if(tab.count(ky) == 0) {return opt;}
979 return get_or(tab.at(ky), opt);
980 }
981
982 template<typename T, typename C,
983 template<typename ...> class M, template<typename ...> class V>
984 detail::enable_if_t<
985 detail::is_exact_toml_type<T, basic_value<C, M, V>>::value, T>&
986 find_or(basic_value<C, M, V>& v, const toml::key& ky, T& opt)
987 {
988 if(!v.is_table()) {return opt;}
989 auto& tab = v.as_table();
990 if(tab.count(ky) == 0) {return opt;}
991 return get_or(tab.at(ky), opt);
992 }
993
994 template<typename T, typename C,
995 template<typename ...> class M, template<typename ...> class V>
996 detail::enable_if_t<
997 detail::is_exact_toml_type<T, basic_value<C, M, V>>::value,
998 detail::remove_cvref_t<T>>
999 find_or(basic_value<C, M, V>&& v, const toml::key& ky, T&& opt)
1000 {
1001 if(!v.is_table()) {return std::forward<T>(opt);}
1002 auto tab = std::move(v).as_table();
1003 if(tab.count(ky) == 0) {return std::forward<T>(opt);}
1004 return get_or(std::move(tab.at(ky)), std::forward<T>(opt));
1005 }
1006
1007 // ---------------------------------------------------------------------------
1008 // std::string (return type can be a reference)
1009
1010 template<typename T, typename C,
1011 template<typename ...> class M, template<typename ...> class V>
1012 detail::enable_if_t<std::is_same<T, std::string>::value, std::string> const&
1013 find_or(const basic_value<C, M, V>& v, const key& ky, const T& opt)
1014 {
1015 if(!v.is_table()) {return opt;}
1016 const auto& tab = v.as_table();
1017 if(tab.count(ky) == 0) {return opt;}
1018 return get_or(tab.at(ky), opt);
1019 }
1020 template<typename T, typename C,
1021 template<typename ...> class M, template<typename ...> class V>
1022 detail::enable_if_t<std::is_same<T, std::string>::value, std::string>&
1023 find_or(basic_value<C, M, V>& v, const toml::key& ky, T& opt)
1024 {
1025 if(!v.is_table()) {return opt;}
1026 auto& tab = v.as_table();
1027 if(tab.count(ky) == 0) {return opt;}
1028 return get_or(tab.at(ky), opt);
1029 }
1030 template<typename T, typename C,
1031 template<typename ...> class M, template<typename ...> class V>
1032 detail::enable_if_t<std::is_same<T, std::string>::value, std::string>
1033 find_or(basic_value<C, M, V>&& v, const toml::key& ky, T&& opt)
1034 {
1035 if(!v.is_table()) {return std::forward<T>(opt);}
1036 auto tab = std::move(v).as_table();
1037 if(tab.count(ky) == 0) {return std::forward<T>(opt);}
1038 return get_or(std::move(tab.at(ky)), std::forward<T>(opt));
1039 }
1040
1041 // ---------------------------------------------------------------------------
1042 // string literal (deduced as std::string)
1043 template<typename T, typename C,
1044 template<typename ...> class M, template<typename ...> class V>
1045 detail::enable_if_t<
1046 detail::is_string_literal<typename std::remove_reference<T>::type>::value,
1047 std::string>
1048 find_or(const basic_value<C, M, V>& v, const toml::key& ky, T&& opt)
1049 {
1050 if(!v.is_table()) {return std::string(opt);}
1051 const auto& tab = v.as_table();
1052 if(tab.count(ky) == 0) {return std::string(opt);}
1053 return get_or(tab.at(ky), std::forward<T>(opt));
1054 }
1055
1056 // ---------------------------------------------------------------------------
1057 // others (require type conversion and return type cannot be lvalue reference)
1058 template<typename T, typename C,
1059 template<typename ...> class M, template<typename ...> class V>
1060 detail::enable_if_t<detail::conjunction<
1061 // T is not an exact toml type
1062 detail::negation<detail::is_exact_toml_type<
1063 detail::remove_cvref_t<T>, basic_value<C, M, V>>>,
1064 // T is not std::string
1065 detail::negation<std::is_same<std::string, detail::remove_cvref_t<T>>>,
1066 // T is not a string literal
1067 detail::negation<detail::is_string_literal<
1068 typename std::remove_reference<T>::type>>
1069 >::value, detail::remove_cvref_t<T>>
1070 find_or(const basic_value<C, M, V>& v, const toml::key& ky, T&& opt)
1071 {
1072 if(!v.is_table()) {return std::forward<T>(opt);}
1073 const auto& tab = v.as_table();
1074 if(tab.count(ky) == 0) {return std::forward<T>(opt);}
1075 return get_or(tab.at(ky), std::forward<T>(opt));
1076 }
1077
1078 // ---------------------------------------------------------------------------
1079 // recursive find-or with type deduction (find_or(value, keys, opt))
1080
1081 template<typename Value, typename ... Ks,
1082 typename detail::enable_if_t<(sizeof...(Ks) > 1), std::nullptr_t> = nullptr>
1083 // here we need to add SFINAE in the template parameter to avoid
1084 // infinite recursion in type deduction on gcc
1085 auto find_or(Value&& v, const toml::key& ky, Ks&& ... keys)
1086 -> decltype(find_or(std::forward<Value>(v), ky, detail::last_one(std::forward<Ks>(keys)...)))
1087 {
1088 if(!v.is_table())
1089 {
1090 return detail::last_one(std::forward<Ks>(keys)...);
1091 }
1092 auto&& tab = std::forward<Value>(v).as_table();
1093 if(tab.count(ky) == 0)
1094 {
1095 return detail::last_one(std::forward<Ks>(keys)...);
1096 }
1097 return find_or(std::forward<decltype(tab)>(tab).at(ky), std::forward<Ks>(keys)...);
1098 }
1099
1100 // ---------------------------------------------------------------------------
1101 // recursive find_or with explicit type specialization, find_or<int>(value, keys...)
1102
1103 template<typename T, typename Value, typename ... Ks,
1104 typename detail::enable_if_t<(sizeof...(Ks) > 1), std::nullptr_t> = nullptr>
1105 // here we need to add SFINAE in the template parameter to avoid
1106 // infinite recursion in type deduction on gcc
1107 auto find_or(Value&& v, const toml::key& ky, Ks&& ... keys)
1108 -> decltype(find_or<T>(std::forward<Value>(v), ky, detail::last_one(std::forward<Ks>(keys)...)))
1109 {
1110 if(!v.is_table())
1111 {
1112 return detail::last_one(std::forward<Ks>(keys)...);
1113 }
1114 auto&& tab = std::forward<Value>(v).as_table();
1115 if(tab.count(ky) == 0)
1116 {
1117 return detail::last_one(std::forward<Ks>(keys)...);
1118 }
1119 return find_or(std::forward<decltype(tab)>(tab).at(ky), std::forward<Ks>(keys)...);
1120 }
1121
1122 // ============================================================================
1123 // expect
1124
1125 template<typename T, typename C,
1126 template<typename ...> class M, template<typename ...> class V>
1127 result<T, std::string> expect(const basic_value<C, M, V>& v) noexcept
1128 {
1129 try
1130 {
1131 return ok(get<T>(v));
1132 }
1133 catch(const std::exception& e)
1134 {
1135 return err(e.what());
1136 }
1137 }
1138 template<typename T, typename C,
1139 template<typename ...> class M, template<typename ...> class V>
1140 result<T, std::string>
1141 expect(const basic_value<C, M, V>& v, const toml::key& k) noexcept
1142 {
1143 try
1144 {
1145 return ok(find<T>(v, k));
1146 }
1147 catch(const std::exception& e)
1148 {
1149 return err(e.what());
1150 }
1151 }
1152
1153 } // toml
1154 #endif// TOML11_GET