libstdc++
safe_iterator.tcc
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1// Debugging iterator implementation (out of line) -*- C++ -*-
2
3// Copyright (C) 2003-2022 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file debug/safe_iterator.tcc
26 * This file is a GNU debug extension to the Standard C++ Library.
27 */
28
29#ifndef _GLIBCXX_DEBUG_SAFE_ITERATOR_TCC
30#define _GLIBCXX_DEBUG_SAFE_ITERATOR_TCC 1
31
32#include <bits/stl_algobase.h>
33
34namespace __gnu_debug
35{
36 template<typename _Iterator, typename _Sequence, typename _Category>
37 typename _Distance_traits<_Iterator>::__type
38 _Safe_iterator<_Iterator, _Sequence, _Category>::
39 _M_get_distance_from_begin() const
40 {
41 typedef _Sequence_traits<_Sequence> _SeqTraits;
42
43 // No need to consider before_begin as this function is only used in
44 // _M_can_advance which won't be used for forward_list iterators.
45 if (_M_is_begin())
46 return std::make_pair(0, __dp_exact);
47
48 if (_M_is_end())
49 return _SeqTraits::_S_size(*_M_get_sequence());
50
51 typename _Distance_traits<_Iterator>::__type __res
52 = __get_distance(_M_get_sequence()->_M_base().begin(), base());
53
54 if (__res.second == __dp_equality)
55 return std::make_pair(1, __dp_sign);
56
57 return __res;
58 }
59
60 template<typename _Iterator, typename _Sequence, typename _Category>
61 typename _Distance_traits<_Iterator>::__type
62 _Safe_iterator<_Iterator, _Sequence, _Category>::
63 _M_get_distance_to_end() const
64 {
65 typedef _Sequence_traits<_Sequence> _SeqTraits;
66
67 // No need to consider before_begin as this function is only used in
68 // _M_can_advance which won't be used for forward_list iterators.
69 if (_M_is_begin())
70 return _SeqTraits::_S_size(*_M_get_sequence());
71
72 if (_M_is_end())
73 return std::make_pair(0, __dp_exact);
74
75 typename _Distance_traits<_Iterator>::__type __res
76 = __get_distance(base(), _M_get_sequence()->_M_base().end());
77
78 if (__res.second == __dp_equality)
79 return std::make_pair(1, __dp_sign);
80
81 return __res;
82 }
83
84 template<typename _Iterator, typename _Sequence, typename _Category>
85 bool
86 _Safe_iterator<_Iterator, _Sequence, _Category>::
87 _M_can_advance(difference_type __n, bool __strict) const
88 {
89 if (this->_M_singular())
90 return false;
91
92 if (__n == 0)
93 return true;
94
95 std::pair<difference_type, _Distance_precision> __dist = __n < 0
96 ? _M_get_distance_from_begin()
97 : _M_get_distance_to_end();
98
99 if (__n < 0)
100 __n = -__n;
101
102 return __dist.second > __dp_sign
103 ? __dist.first >= __n
104 : !__strict && __dist.first > 0;
105 }
106
107 template<typename _Iterator, typename _Sequence, typename _Category>
108 template<typename _Diff>
109 bool
110 _Safe_iterator<_Iterator, _Sequence, _Category>::
111 _M_can_advance(const std::pair<_Diff, _Distance_precision>& __dist,
112 int __way) const
113 {
114 return __dist.second == __dp_exact
115 ? _M_can_advance(__way * __dist.first)
116 : _M_can_advance(__way * (__dist.first == 0
117 ? 0
118 : __dist.first < 0 ? -1 : 1));
119 }
120
121 template<typename _Iterator, typename _Sequence, typename _Category>
122 typename _Distance_traits<_Iterator>::__type
123 _Safe_iterator<_Iterator, _Sequence, _Category>::
124 _M_get_distance_to(const _Safe_iterator& __rhs) const
125 {
126 typedef typename _Distance_traits<_Iterator>::__type _Dist;
127 typedef _Sequence_traits<_Sequence> _SeqTraits;
128
129 _Dist __base_dist = __get_distance(this->base(), __rhs.base());
130 if (__base_dist.second == __dp_exact)
131 return __base_dist;
132
133 _Dist __seq_dist = _SeqTraits::_S_size(*this->_M_get_sequence());
134 if (this->_M_is_before_begin())
135 {
136 if (__rhs._M_is_begin())
137 return std::make_pair(1, __dp_exact);
138
139 return __seq_dist.second == __dp_exact
140 ? std::make_pair(__seq_dist.first + 1, __dp_exact)
141 : __seq_dist;
142 }
143
144 if (this->_M_is_begin())
145 {
146 if (__rhs._M_is_before_begin())
147 return std::make_pair(-1, __dp_exact);
148
149 if (__rhs._M_is_end())
150 return __seq_dist;
151
152 return std::make_pair(__seq_dist.first,
153 __seq_dist.second == __dp_exact
154 ? __dp_sign_max_size : __seq_dist.second);
155 }
156
157 if (this->_M_is_end())
158 {
159 if (__rhs._M_is_before_begin())
160 return __seq_dist.second == __dp_exact
161 ? std::make_pair(-__seq_dist.first - 1, __dp_exact)
162 : std::make_pair(-__seq_dist.first, __dp_sign);
163
164 if (__rhs._M_is_begin())
165 return std::make_pair(-__seq_dist.first, __seq_dist.second);
166
167 return std::make_pair(-__seq_dist.first,
168 __seq_dist.second == __dp_exact
169 ? __dp_sign_max_size : __seq_dist.second);
170 }
171
172 if (__rhs._M_is_before_begin())
173 return __seq_dist.second == __dp_exact
174 ? std::make_pair(__seq_dist.first - 1, __dp_exact)
175 : std::make_pair(-__seq_dist.first, __dp_sign);
176
177 if (__rhs._M_is_begin())
178 return std::make_pair(-__seq_dist.first,
179 __seq_dist.second == __dp_exact
180 ? __dp_sign_max_size : __seq_dist.second);
181
182 if (__rhs._M_is_end())
183 return std::make_pair(__seq_dist.first,
184 __seq_dist.second == __dp_exact
185 ? __dp_sign_max_size : __seq_dist.second);
186
187 return std::make_pair(1, __dp_equality);
188 }
189
190 template<typename _Iterator, typename _Sequence, typename _Category>
191 bool
192 _Safe_iterator<_Iterator, _Sequence, _Category>::
193 _M_valid_range(const _Safe_iterator& __rhs,
194 std::pair<difference_type, _Distance_precision>& __dist,
195 bool __check_dereferenceable) const
196 {
197 if (_M_singular() || __rhs._M_singular() || !_M_can_compare(__rhs))
198 return false;
199
200 /* Determine iterators order */
201 __dist = _M_get_distance_to(__rhs);
202 if (__dist.second != __dp_equality)
203 {
204 // If range is not empty first iterator must be dereferenceable.
205 return __dist.first == 0
206 || (__dist.first > 0
207 && (!__check_dereferenceable || _M_dereferenceable()));
208 }
209
210 // Assume that this is a valid range; we can't check anything else.
211 return true;
212 }
213
214 template<typename _Iterator, typename _Sequence>
215 bool
216 _Safe_iterator<_Iterator, _Sequence, std::random_access_iterator_tag>::
217 _M_valid_range(const _Safe_iterator& __rhs,
218 std::pair<difference_type,
219 _Distance_precision>& __dist) const
220 {
221 if (this->_M_singular() || __rhs._M_singular()
222 || !this->_M_can_compare(__rhs))
223 return false;
224
225 /* Determine iterators order */
226 __dist = std::make_pair(__rhs.base() - this->base(), __dp_exact);
227
228 // If range is not empty first iterator must be dereferenceable.
229 return __dist.first == 0
230 || (__dist.first > 0 && this->_M_dereferenceable());
231 }
232} // namespace __gnu_debug
233
234namespace std _GLIBCXX_VISIBILITY(default)
235{
236_GLIBCXX_BEGIN_NAMESPACE_VERSION
237
238 template<typename _Ite, typename _Seq>
239 _Ite
240 __niter_base(const ::__gnu_debug::_Safe_iterator<_Ite, _Seq,
241 std::random_access_iterator_tag>& __it)
242 { return __it.base(); }
243
244 template<bool _IsMove,
245 typename _Ite, typename _Seq, typename _Cat, typename _OI>
246 _OI
247 __copy_move_a(
248 const ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>& __first,
249 const ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>& __last,
250 _OI __result)
251 {
252 typename ::__gnu_debug::_Distance_traits<_Ite>::__type __dist;
253 __glibcxx_check_valid_range2(__first, __last, __dist);
254 __glibcxx_check_can_increment_dist(__result, __dist, 1);
255
256 if (__dist.second > ::__gnu_debug::__dp_equality)
257 return std::__copy_move_a<_IsMove>(__first.base(), __last.base(),
258 __result);
259
260 return std::__copy_move_a1<_IsMove>(__first, __last, __result);
261 }
262
263 template<bool _IsMove,
264 typename _II, typename _Ite, typename _Seq, typename _Cat>
265 __gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>
266 __copy_move_a(_II __first, _II __last,
267 const ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>& __result)
268 {
269 typename ::__gnu_debug::_Distance_traits<_II>::__type __dist;
270 __glibcxx_check_valid_range2(__first, __last, __dist);
271 __glibcxx_check_can_increment_dist(__result, __dist, 1);
272
273 if (__dist.second > ::__gnu_debug::__dp_sign
274 && __result._M_can_advance(__dist.first, true))
275 return ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>(
276 std::__copy_move_a<_IsMove>(__first, __last, __result.base()),
277 __result._M_sequence);
278
279 return std::__copy_move_a1<_IsMove>(__first, __last, __result);
280 }
281
282 template<bool _IsMove,
283 typename _IIte, typename _ISeq, typename _ICat,
284 typename _OIte, typename _OSeq, typename _OCat>
285 ::__gnu_debug::_Safe_iterator<_OIte, _OSeq, _OCat>
286 __copy_move_a(
287 const ::__gnu_debug::_Safe_iterator<_IIte, _ISeq, _ICat>& __first,
288 const ::__gnu_debug::_Safe_iterator<_IIte, _ISeq, _ICat>& __last,
289 const ::__gnu_debug::_Safe_iterator<_OIte, _OSeq, _OCat>& __result)
290 {
291 typename ::__gnu_debug::_Distance_traits<_IIte>::__type __dist;
292 __glibcxx_check_valid_range2(__first, __last, __dist);
293 __glibcxx_check_can_increment_dist(__result, __dist, 1);
294
295 if (__dist.second > ::__gnu_debug::__dp_equality)
296 {
297 if (__dist.second > ::__gnu_debug::__dp_sign
298 && __result._M_can_advance(__dist.first, true))
299 return ::__gnu_debug::_Safe_iterator<_OIte, _OSeq, _OCat>(
300 std::__copy_move_a<_IsMove>(__first.base(), __last.base(),
301 __result.base()),
302 __result._M_sequence);
303
304 return std::__copy_move_a<_IsMove>(__first.base(), __last.base(),
305 __result);
306 }
307
308 return std::__copy_move_a1<_IsMove>(__first, __last, __result);
309 }
310
311 template<bool _IsMove,
312 typename _Ite, typename _Seq, typename _Cat, typename _OI>
313 _OI
314 __copy_move_backward_a(
315 const ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>& __first,
316 const ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>& __last,
317 _OI __result)
318 {
319 typename ::__gnu_debug::_Distance_traits<_Ite>::__type __dist;
320 __glibcxx_check_valid_range2(__first, __last, __dist);
321 __glibcxx_check_can_increment_dist(__result, __dist, -1);
322
323 if (__dist.second > ::__gnu_debug::__dp_equality)
324 return std::__copy_move_backward_a<_IsMove>(
325 __first.base(), __last.base(), __result);
326
327 return std::__copy_move_backward_a1<_IsMove>(__first, __last, __result);
328 }
329
330 template<bool _IsMove,
331 typename _II, typename _Ite, typename _Seq, typename _Cat>
332 __gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>
333 __copy_move_backward_a(_II __first, _II __last,
334 const ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>& __result)
335 {
336 typename ::__gnu_debug::_Distance_traits<_II>::__type __dist;
337 __glibcxx_check_valid_range2(__first, __last, __dist);
338 __glibcxx_check_can_increment_dist(__result, __dist, -1);
339
340 if (__dist.second > ::__gnu_debug::__dp_sign
341 && __result._M_can_advance(-__dist.first, true))
342 return ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>(
343 std::__copy_move_backward_a<_IsMove>(__first, __last,
344 __result.base()),
345 __result._M_sequence);
346
347 return std::__copy_move_backward_a1<_IsMove>(__first, __last, __result);
348 }
349
350 template<bool _IsMove,
351 typename _IIte, typename _ISeq, typename _ICat,
352 typename _OIte, typename _OSeq, typename _OCat>
353 ::__gnu_debug::_Safe_iterator<_OIte, _OSeq, _OCat>
354 __copy_move_backward_a(
355 const ::__gnu_debug::_Safe_iterator<_IIte, _ISeq, _ICat>& __first,
356 const ::__gnu_debug::_Safe_iterator<_IIte, _ISeq, _ICat>& __last,
357 const ::__gnu_debug::_Safe_iterator<_OIte, _OSeq, _OCat>& __result)
358 {
359 typename ::__gnu_debug::_Distance_traits<_IIte>::__type __dist;
360 __glibcxx_check_valid_range2(__first, __last, __dist);
361 __glibcxx_check_can_increment_dist(__result, __dist, -1);
362
363 if (__dist.second > ::__gnu_debug::__dp_equality)
364 {
365 if (__dist.second > ::__gnu_debug::__dp_sign
366 && __result._M_can_advance(-__dist.first, true))
367 return ::__gnu_debug::_Safe_iterator<_OIte, _OSeq, _OCat>(
368 std::__copy_move_backward_a<_IsMove>(__first.base(), __last.base(),
369 __result.base()),
370 __result._M_sequence);
371
372 return std::__copy_move_backward_a<_IsMove>(
373 __first.base(), __last.base(), __result);
374 }
375
376 return std::__copy_move_backward_a1<_IsMove>(__first, __last, __result);
377 }
378
379 template<typename _Ite, typename _Seq, typename _Cat, typename _Tp>
380 void
381 __fill_a(const ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>& __first,
382 const ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>& __last,
383 const _Tp& __value)
384 {
385 typename ::__gnu_debug::_Distance_traits<_Ite>::__type __dist;
386 __glibcxx_check_valid_range2(__first, __last, __dist);
387
388 if (__dist.second > ::__gnu_debug::__dp_equality)
389 std::__fill_a(__first.base(), __last.base(), __value);
390
391 std::__fill_a1(__first, __last, __value);
392 }
393
394 template<typename _Ite, typename _Seq, typename _Cat, typename _Size,
395 typename _Tp>
396 ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>
397 __fill_n_a(const ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>& __first,
398 _Size __n, const _Tp& __value,
399 std::input_iterator_tag)
400 {
401#if __cplusplus >= 201103L
402 static_assert(is_integral<_Size>{}, "fill_n must pass integral size");
403#endif
404
405 if (__n <= 0)
406 return __first;
407
408 __glibcxx_check_can_increment(__first, __n);
409 if (__first._M_can_advance(__n, true))
410 return ::__gnu_debug::_Safe_iterator<_Ite, _Seq, _Cat>(
411 std::__fill_n_a(__first.base(), __n, __value, _Cat()),
412 __first._M_sequence);
413
414 return std::__fill_n_a1(__first, __n, __value);
415 }
416
417 template<typename _II1, typename _Seq1, typename _Cat1, typename _II2>
418 bool
419 __equal_aux(
420 const ::__gnu_debug::_Safe_iterator<_II1, _Seq1, _Cat1>& __first1,
421 const ::__gnu_debug::_Safe_iterator<_II1, _Seq1, _Cat1>& __last1,
422 _II2 __first2)
423 {
424 typename ::__gnu_debug::_Distance_traits<_II1>::__type __dist;
425 __glibcxx_check_valid_range2(__first1, __last1, __dist);
426 __glibcxx_check_can_increment_dist(__first2, __dist, 1);
427
428 if (__dist.second > ::__gnu_debug::__dp_equality)
429 return std::__equal_aux(__first1.base(), __last1.base(), __first2);
430
431 return std::__equal_aux1(__first1, __last1, __first2);
432 }
433
434 template<typename _II1, typename _II2, typename _Seq2, typename _Cat2>
435 bool
436 __equal_aux(_II1 __first1, _II1 __last1,
437 const ::__gnu_debug::_Safe_iterator<_II2, _Seq2, _Cat2>& __first2)
438 {
439 typename ::__gnu_debug::_Distance_traits<_II1>::__type __dist;
440 __glibcxx_check_valid_range2(__first1, __last1, __dist);
441 __glibcxx_check_can_increment_dist(__first2, __dist, 1);
442
443 if (__dist.second > ::__gnu_debug::__dp_sign
444 && __first2._M_can_advance(__dist.first, true))
445 return std::__equal_aux(__first1, __last1, __first2.base());
446
447 return std::__equal_aux1(__first1, __last1, __first2);
448 }
449
450 template<typename _II1, typename _Seq1, typename _Cat1,
451 typename _II2, typename _Seq2, typename _Cat2>
452 bool
453 __equal_aux(
454 const ::__gnu_debug::_Safe_iterator<_II1, _Seq1, _Cat1>& __first1,
455 const ::__gnu_debug::_Safe_iterator<_II1, _Seq1, _Cat1>& __last1,
456 const ::__gnu_debug::_Safe_iterator<_II2, _Seq2, _Cat2>& __first2)
457 {
458 typename ::__gnu_debug::_Distance_traits<_II1>::__type __dist;
459 __glibcxx_check_valid_range2(__first1, __last1, __dist);
460 __glibcxx_check_can_increment_dist(__first2, __dist, 1);
461
462 if (__dist.second > ::__gnu_debug::__dp_equality)
463 {
464 if (__dist.second > ::__gnu_debug::__dp_sign &&
465 __first2._M_can_advance(__dist.first, true))
466 return std::__equal_aux(__first1.base(), __last1.base(),
467 __first2.base());
468 return std::__equal_aux(__first1.base(), __last1.base(), __first2);
469 }
470
471 return __equal_aux1(__first1, __last1, __first2);
472 }
473
474 template<typename _Ite1, typename _Seq1, typename _Cat1,
475 typename _II2>
476 bool
477 __lexicographical_compare_aux(
478 const ::__gnu_debug::_Safe_iterator<_Ite1, _Seq1, _Cat1>& __first1,
479 const ::__gnu_debug::_Safe_iterator<_Ite1, _Seq1, _Cat1>& __last1,
480 _II2 __first2, _II2 __last2)
481 {
482 typename ::__gnu_debug::_Distance_traits<_Ite1>::__type __dist1;
483 __glibcxx_check_valid_range2(__first1, __last1, __dist1);
484 __glibcxx_check_valid_range(__first2, __last2);
485
486 if (__dist1.second > ::__gnu_debug::__dp_equality)
487 return std::__lexicographical_compare_aux(__first1.base(),
488 __last1.base(),
489 __first2, __last2);
490 return std::__lexicographical_compare_aux1(__first1, __last1,
491 __first2, __last2);
492 }
493
494 template<typename _II1,
495 typename _Ite2, typename _Seq2, typename _Cat2>
496 bool
497 __lexicographical_compare_aux(
498 _II1 __first1, _II1 __last1,
499 const ::__gnu_debug::_Safe_iterator<_Ite2, _Seq2, _Cat2>& __first2,
500 const ::__gnu_debug::_Safe_iterator<_Ite2, _Seq2, _Cat2>& __last2)
501 {
502 __glibcxx_check_valid_range(__first1, __last1);
503 typename ::__gnu_debug::_Distance_traits<_II1>::__type __dist2;
504 __glibcxx_check_valid_range2(__first2, __last2, __dist2);
505
506 if (__dist2.second > ::__gnu_debug::__dp_equality)
507 return std::__lexicographical_compare_aux(__first1, __last1,
508 __first2.base(),
509 __last2.base());
510 return std::__lexicographical_compare_aux1(__first1, __last1,
511 __first2, __last2);
512 }
513
514 template<typename _Ite1, typename _Seq1, typename _Cat1,
515 typename _Ite2, typename _Seq2, typename _Cat2>
516 bool
517 __lexicographical_compare_aux(
518 const ::__gnu_debug::_Safe_iterator<_Ite1, _Seq1, _Cat1>& __first1,
519 const ::__gnu_debug::_Safe_iterator<_Ite1, _Seq1, _Cat1>& __last1,
520 const ::__gnu_debug::_Safe_iterator<_Ite2, _Seq2, _Cat2>& __first2,
521 const ::__gnu_debug::_Safe_iterator<_Ite2, _Seq2, _Cat2>& __last2)
522 {
523 typename ::__gnu_debug::_Distance_traits<_Ite1>::__type __dist1;
524 __glibcxx_check_valid_range2(__first1, __last1, __dist1);
525 typename ::__gnu_debug::_Distance_traits<_Ite2>::__type __dist2;
526 __glibcxx_check_valid_range2(__first2, __last2, __dist2);
527
528 if (__dist1.second > ::__gnu_debug::__dp_equality)
529 {
530 if (__dist2.second > ::__gnu_debug::__dp_equality)
531 return std::__lexicographical_compare_aux(__first1.base(),
532 __last1.base(),
533 __first2.base(),
534 __last2.base());
535 return std::__lexicographical_compare_aux(__first1.base(),
536 __last1.base(),
537 __first2, __last2);
538 }
539
540 if (__dist2.second > ::__gnu_debug::__dp_equality)
541 return std::__lexicographical_compare_aux(__first1, __last1,
542 __first2.base(),
543 __last2.base());
544 return std::__lexicographical_compare_aux1(__first1, __last1,
545 __first2, __last2);
546 }
547
548_GLIBCXX_END_NAMESPACE_VERSION
549} // namespace std
550
551#endif
std
ISO C++ entities toplevel namespace is std.
__gnu_debug
GNU debug classes for public use.
Definition: boost_concept_check.h:58
__gnu_debug::__get_distance
constexpr _Distance_traits< _Iterator >::__type __get_distance(_Iterator __lhs, _Iterator __rhs, std::random_access_iterator_tag)
Definition: helper_functions.h:94
__gnu_debug::_Safe_iterator
Safe iterator wrapper.
Definition: safe_iterator.h:117
std::pair
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:187
std::pair::first
_T1 first
The first member.
Definition: stl_pair.h:191
std::pair::second
_T2 second
The second member.
Definition: stl_pair.h:192
std::input_iterator_tag
Marking input iterators.
Definition: stl_iterator_base_types.h:93
std::random_access_iterator_tag
Random-access iterators support a superset of bidirectional iterator operations.
Definition: stl_iterator_base_types.h:107