libstdc++
functional
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1// <functional> -*- C++ -*-
2
3// Copyright (C) 2001-2025 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/*
26 * Copyright (c) 1997
27 * Silicon Graphics Computer Systems, Inc.
28 *
29 * Permission to use, copy, modify, distribute and sell this software
30 * and its documentation for any purpose is hereby granted without fee,
31 * provided that the above copyright notice appear in all copies and
32 * that both that copyright notice and this permission notice appear
33 * in supporting documentation. Silicon Graphics makes no
34 * representations about the suitability of this software for any
35 * purpose. It is provided "as is" without express or implied warranty.
36 *
37 */
38
39/** @file include/functional
40 * This is a Standard C++ Library header.
41 */
42
43#ifndef _GLIBCXX_FUNCTIONAL
44#define _GLIBCXX_FUNCTIONAL 1
45
46#ifdef _GLIBCXX_SYSHDR
47#pragma GCC system_header
48#endif
49
50#include <bits/c++config.h>
51#include <bits/stl_function.h> // std::equal_to, std::unary_function etc.
52
53#if __cplusplus >= 201103L
54
55#define __glibcxx_want_boyer_moore_searcher
56#define __glibcxx_want_bind_front
57#define __glibcxx_want_bind_back
58#define __glibcxx_want_constexpr_functional
59#define __glibcxx_want_copyable_function
60#define __glibcxx_want_function_ref
61#define __glibcxx_want_invoke
62#define __glibcxx_want_invoke_r
63#define __glibcxx_want_move_only_function
64#define __glibcxx_want_not_fn
65#define __glibcxx_want_ranges
66#define __glibcxx_want_reference_wrapper
67#define __glibcxx_want_transparent_operators
68#include <bits/version.h>
69
70#include <tuple>
71#include <bits/functional_hash.h>
72#include <bits/invoke.h>
73#include <bits/refwrap.h> // std::reference_wrapper and _Mem_fn_traits
74#if _GLIBCXX_HOSTED
75# include <bits/std_function.h> // std::function
76#endif
77#if __cplusplus >= 201703L
78# if _GLIBCXX_HOSTED
79# include <unordered_map>
80# include <vector>
81# include <array>
82# endif
83# include <bits/stl_algobase.h> // std::search
84#endif
85#if __cplusplus >= 202002L
86# include <bits/binders.h>
87# include <bits/ranges_cmp.h> // std::identity, ranges::equal_to etc.
88# include <compare>
89#endif
90#if __glibcxx_move_only_function || __glibcxx_copyable_function || \
91 __glibcxx_function_ref
92# include <bits/funcwrap.h>
93#endif
94
95#endif // C++11
96
97namespace std _GLIBCXX_VISIBILITY(default)
98{
99_GLIBCXX_BEGIN_NAMESPACE_VERSION
100
101 /** @brief The type of placeholder objects defined by libstdc++.
102 * @ingroup binders
103 * @since C++11
104 */
105 template<int _Num> struct _Placeholder { };
106
107#ifdef __cpp_lib_invoke // C++ >= 17
108
109 /** Invoke a callable object.
110 *
111 * `std::invoke` takes a callable object as its first argument and calls it
112 * with the remaining arguments. The callable object can be a pointer or
113 * reference to a function, a lambda closure, a class with `operator()`,
114 * or even a pointer-to-member. For a pointer-to-member the first argument
115 * must be a reference or pointer to the object that the pointer-to-member
116 * will be applied to.
117 *
118 * @since C++17
119 */
120 template<typename _Callable, typename... _Args>
121 inline _GLIBCXX20_CONSTEXPR invoke_result_t<_Callable, _Args...>
122 invoke(_Callable&& __fn, _Args&&... __args)
123 noexcept(is_nothrow_invocable_v<_Callable, _Args...>)
124 {
125 return std::__invoke(std::forward<_Callable>(__fn),
126 std::forward<_Args>(__args)...);
127 }
128#endif
129
130#ifdef __cpp_lib_invoke_r // C++ >= 23
131
132 /** Invoke a callable object and convert the result to `_Res`.
133 *
134 * `std::invoke_r<R>(f, args...)` is equivalent to `std::invoke(f, args...)`
135 * with the result implicitly converted to `R`.
136 *
137 * @since C++23
138 */
139 template<typename _Res, typename _Callable, typename... _Args>
140 requires is_invocable_r_v<_Res, _Callable, _Args...>
141 constexpr _Res
142 invoke_r(_Callable&& __fn, _Args&&... __args)
143 noexcept(is_nothrow_invocable_r_v<_Res, _Callable, _Args...>)
144 {
145 return std::__invoke_r<_Res>(std::forward<_Callable>(__fn),
146 std::forward<_Args>(__args)...);
147 }
148#endif // __cpp_lib_invoke_r
149
150 /// @cond undocumented
151
152#if __cplusplus >= 201103L
153 template<typename _MemFunPtr,
154 bool __is_mem_fn = is_member_function_pointer<_MemFunPtr>::value>
155 class _Mem_fn_base
156 : public _Mem_fn_traits<_MemFunPtr>::__maybe_type
157 {
158 using _Traits = _Mem_fn_traits<_MemFunPtr>;
159
160 using _Arity = typename _Traits::__arity;
161 using _Varargs = typename _Traits::__vararg;
162
163 template<typename _Func, typename... _BoundArgs>
164 friend struct _Bind_check_arity;
165
166 _MemFunPtr _M_pmf;
167
168 public:
169
170 using result_type = typename _Traits::__result_type;
171
172 explicit constexpr
173 _Mem_fn_base(_MemFunPtr __pmf) noexcept : _M_pmf(__pmf) { }
174
175 template<typename... _Args>
176 _GLIBCXX20_CONSTEXPR
177 auto
178 operator()(_Args&&... __args) const
179 noexcept(noexcept(
180 std::__invoke(_M_pmf, std::forward<_Args>(__args)...)))
181 -> decltype(std::__invoke(_M_pmf, std::forward<_Args>(__args)...))
182 { return std::__invoke(_M_pmf, std::forward<_Args>(__args)...); }
183 };
184
185 // Partial specialization for member object pointers.
186 template<typename _MemObjPtr>
187 class _Mem_fn_base<_MemObjPtr, false>
188 {
189 using _Arity = integral_constant<size_t, 0>;
190 using _Varargs = false_type;
191
192 template<typename _Func, typename... _BoundArgs>
193 friend struct _Bind_check_arity;
194
195 _MemObjPtr _M_pm;
196
197 public:
198 explicit constexpr
199 _Mem_fn_base(_MemObjPtr __pm) noexcept : _M_pm(__pm) { }
200
201 template<typename _Tp>
202 _GLIBCXX20_CONSTEXPR
203 auto
204 operator()(_Tp&& __obj) const
205 noexcept(noexcept(std::__invoke(_M_pm, std::forward<_Tp>(__obj))))
206 -> decltype(std::__invoke(_M_pm, std::forward<_Tp>(__obj)))
207 { return std::__invoke(_M_pm, std::forward<_Tp>(__obj)); }
208 };
209
210 template<typename _MemberPointer>
211 struct _Mem_fn; // undefined
212
213 template<typename _Res, typename _Class>
214 struct _Mem_fn<_Res _Class::*>
215 : _Mem_fn_base<_Res _Class::*>
216 {
217 using _Mem_fn_base<_Res _Class::*>::_Mem_fn_base;
218 };
219 /// @endcond
220
221 // _GLIBCXX_RESOLVE_LIB_DEFECTS
222 // 2048. Unnecessary mem_fn overloads
223 /**
224 * @brief Returns a function object that forwards to the member pointer
225 * pointer `pm`.
226 *
227 * This allows a pointer-to-member to be transformed into a function object
228 * that can be called with an object expression as its first argument.
229 *
230 * For a pointer-to-data-member the result must be called with exactly one
231 * argument, the object expression that would be used as the first operand
232 * in a `obj.*memptr` or `objp->*memptr` expression.
233 *
234 * For a pointer-to-member-function the result must be called with an object
235 * expression and any additional arguments to pass to the member function,
236 * as in an expression like `(obj.*memfun)(args...)` or
237 * `(objp->*memfun)(args...)`.
238 *
239 * The object expression can be a pointer, reference, `reference_wrapper`,
240 * or smart pointer, and the call wrapper will dereference it as needed
241 * to apply the pointer-to-member.
242 *
243 * @ingroup functors
244 * @since C++11
245 */
246 template<typename _Tp, typename _Class>
247 _GLIBCXX20_CONSTEXPR
248 inline _Mem_fn<_Tp _Class::*>
249 mem_fn(_Tp _Class::* __pm) noexcept
250 {
251 return _Mem_fn<_Tp _Class::*>(__pm);
252 }
253
254 /**
255 * @brief Trait that identifies a bind expression.
256 *
257 * Determines if the given type `_Tp` is a function object that
258 * should be treated as a subexpression when evaluating calls to
259 * function objects returned by `std::bind`.
260 *
261 * C++11 [func.bind.isbind].
262 * @ingroup binders
263 * @since C++11
264 */
265 template<typename _Tp>
266 struct is_bind_expression
267 : public false_type { };
268
269 /**
270 * @brief Determines if the given type _Tp is a placeholder in a
271 * bind() expression and, if so, which placeholder it is.
272 *
273 * C++11 [func.bind.isplace].
274 * @ingroup binders
275 * @since C++11
276 */
277 template<typename _Tp>
278 struct is_placeholder
279 : public integral_constant<int, 0>
280 { };
281
282#if __cplusplus > 201402L
283 template <typename _Tp> inline constexpr bool is_bind_expression_v
284 = is_bind_expression<_Tp>::value;
285 template <typename _Tp> inline constexpr int is_placeholder_v
286 = is_placeholder<_Tp>::value;
287#endif // C++17
288
289 /** @namespace std::placeholders
290 * @brief ISO C++ 2011 namespace for std::bind placeholders.
291 * @ingroup binders
292 * @since C++11
293 */
294 namespace placeholders
295 {
296 /* Define a large number of placeholders. There is no way to
297 * simplify this with variadic templates, because we're introducing
298 * unique names for each.
299 */
300#if __cpp_inline_variables
301# define _GLIBCXX_PLACEHOLDER inline
302#else
303# define _GLIBCXX_PLACEHOLDER extern
304#endif
305
306 _GLIBCXX_PLACEHOLDER const _Placeholder<1> _1;
307 _GLIBCXX_PLACEHOLDER const _Placeholder<2> _2;
308 _GLIBCXX_PLACEHOLDER const _Placeholder<3> _3;
309 _GLIBCXX_PLACEHOLDER const _Placeholder<4> _4;
310 _GLIBCXX_PLACEHOLDER const _Placeholder<5> _5;
311 _GLIBCXX_PLACEHOLDER const _Placeholder<6> _6;
312 _GLIBCXX_PLACEHOLDER const _Placeholder<7> _7;
313 _GLIBCXX_PLACEHOLDER const _Placeholder<8> _8;
314 _GLIBCXX_PLACEHOLDER const _Placeholder<9> _9;
315 _GLIBCXX_PLACEHOLDER const _Placeholder<10> _10;
316 _GLIBCXX_PLACEHOLDER const _Placeholder<11> _11;
317 _GLIBCXX_PLACEHOLDER const _Placeholder<12> _12;
318 _GLIBCXX_PLACEHOLDER const _Placeholder<13> _13;
319 _GLIBCXX_PLACEHOLDER const _Placeholder<14> _14;
320 _GLIBCXX_PLACEHOLDER const _Placeholder<15> _15;
321 _GLIBCXX_PLACEHOLDER const _Placeholder<16> _16;
322 _GLIBCXX_PLACEHOLDER const _Placeholder<17> _17;
323 _GLIBCXX_PLACEHOLDER const _Placeholder<18> _18;
324 _GLIBCXX_PLACEHOLDER const _Placeholder<19> _19;
325 _GLIBCXX_PLACEHOLDER const _Placeholder<20> _20;
326 _GLIBCXX_PLACEHOLDER const _Placeholder<21> _21;
327 _GLIBCXX_PLACEHOLDER const _Placeholder<22> _22;
328 _GLIBCXX_PLACEHOLDER const _Placeholder<23> _23;
329 _GLIBCXX_PLACEHOLDER const _Placeholder<24> _24;
330 _GLIBCXX_PLACEHOLDER const _Placeholder<25> _25;
331 _GLIBCXX_PLACEHOLDER const _Placeholder<26> _26;
332 _GLIBCXX_PLACEHOLDER const _Placeholder<27> _27;
333 _GLIBCXX_PLACEHOLDER const _Placeholder<28> _28;
334 _GLIBCXX_PLACEHOLDER const _Placeholder<29> _29;
335
336#undef _GLIBCXX_PLACEHOLDER
337 }
338
339 /**
340 * Partial specialization of is_placeholder that provides the placeholder
341 * number for the placeholder objects defined by libstdc++.
342 * @ingroup binders
343 * @since C++11
344 */
345 template<int _Num>
346 struct is_placeholder<_Placeholder<_Num> >
347 : public integral_constant<int, _Num>
348 { };
349
350 template<int _Num>
351 struct is_placeholder<const _Placeholder<_Num> >
352 : public integral_constant<int, _Num>
353 { };
354
355 /// @cond undocumented
356
357 // Like tuple_element_t but SFINAE-friendly.
358 template<std::size_t __i, typename _Tuple>
359 using _Safe_tuple_element_t
360 = typename enable_if<(__i < tuple_size<_Tuple>::value),
361 tuple_element<__i, _Tuple>>::type::type;
362
363 /**
364 * Maps an argument to bind() into an actual argument to the bound
365 * function object [func.bind.bind]/10. Only the first parameter should
366 * be specified: the rest are used to determine among the various
367 * implementations. Note that, although this class is a function
368 * object, it isn't entirely normal because it takes only two
369 * parameters regardless of the number of parameters passed to the
370 * bind expression. The first parameter is the bound argument and
371 * the second parameter is a tuple containing references to the
372 * rest of the arguments.
373 */
374 template<typename _Arg,
375 bool _IsBindExp = is_bind_expression<_Arg>::value,
376 bool _IsPlaceholder = (is_placeholder<_Arg>::value > 0)>
377 class _Mu;
378
379 /**
380 * If the argument is reference_wrapper<_Tp>, returns the
381 * underlying reference.
382 * C++11 [func.bind.bind] p10 bullet 1.
383 */
384 template<typename _Tp>
385 class _Mu<reference_wrapper<_Tp>, false, false>
386 {
387 public:
388 /* Note: This won't actually work for const volatile
389 * reference_wrappers, because reference_wrapper::get() is const
390 * but not volatile-qualified. This might be a defect in the TR.
391 */
392 template<typename _CVRef, typename _Tuple>
393 _GLIBCXX20_CONSTEXPR
394 _Tp&
395 operator()(_CVRef& __arg, _Tuple&) const volatile
396 { return __arg.get(); }
397 };
398
399 /**
400 * If the argument is a bind expression, we invoke the underlying
401 * function object with the same cv-qualifiers as we are given and
402 * pass along all of our arguments (unwrapped).
403 * C++11 [func.bind.bind] p10 bullet 2.
404 */
405 template<typename _Arg>
406 class _Mu<_Arg, true, false>
407 {
408 public:
409 template<typename _CVArg, typename... _Args>
410 _GLIBCXX20_CONSTEXPR
411 auto
412 operator()(_CVArg& __arg,
413 tuple<_Args...>& __tuple) const volatile
414 -> decltype(__arg(declval<_Args>()...))
415 {
416 // Construct an index tuple and forward to __call
417 typedef typename _Build_index_tuple<sizeof...(_Args)>::__type
418 _Indexes;
419 return this->__call(__arg, __tuple, _Indexes());
420 }
421
422 private:
423 // Invokes the underlying function object __arg by unpacking all
424 // of the arguments in the tuple.
425 template<typename _CVArg, typename... _Args, std::size_t... _Indexes>
426 _GLIBCXX20_CONSTEXPR
427 auto
428 __call(_CVArg& __arg, tuple<_Args...>& __tuple,
429 const _Index_tuple<_Indexes...>&) const volatile
430 -> decltype(__arg(declval<_Args>()...))
431 {
432 return __arg(std::get<_Indexes>(std::move(__tuple))...);
433 }
434 };
435
436 /**
437 * If the argument is a placeholder for the Nth argument, returns
438 * a reference to the Nth argument to the bind function object.
439 * C++11 [func.bind.bind] p10 bullet 3.
440 */
441 template<typename _Arg>
442 class _Mu<_Arg, false, true>
443 {
444 public:
445 template<typename _Tuple>
446 _GLIBCXX20_CONSTEXPR
447 _Safe_tuple_element_t<(is_placeholder<_Arg>::value - 1), _Tuple>&&
448 operator()(const volatile _Arg&, _Tuple& __tuple) const volatile
449 {
450 return
451 ::std::get<(is_placeholder<_Arg>::value - 1)>(std::move(__tuple));
452 }
453 };
454
455 /**
456 * If the argument is just a value, returns a reference to that
457 * value. The cv-qualifiers on the reference are determined by the caller.
458 * C++11 [func.bind.bind] p10 bullet 4.
459 */
460 template<typename _Arg>
461 class _Mu<_Arg, false, false>
462 {
463 public:
464 template<typename _CVArg, typename _Tuple>
465 _GLIBCXX20_CONSTEXPR
466 _CVArg&&
467 operator()(_CVArg&& __arg, _Tuple&) const volatile
468 { return std::forward<_CVArg>(__arg); }
469 };
470
471 // std::get<I> for volatile-qualified tuples
472 template<std::size_t _Ind, typename... _Tp>
473 inline auto
474 __volget(volatile tuple<_Tp...>& __tuple)
475 -> __tuple_element_t<_Ind, tuple<_Tp...>> volatile&
476 { return std::get<_Ind>(const_cast<tuple<_Tp...>&>(__tuple)); }
477
478 // std::get<I> for const-volatile-qualified tuples
479 template<std::size_t _Ind, typename... _Tp>
480 inline auto
481 __volget(const volatile tuple<_Tp...>& __tuple)
482 -> __tuple_element_t<_Ind, tuple<_Tp...>> const volatile&
483 { return std::get<_Ind>(const_cast<const tuple<_Tp...>&>(__tuple)); }
484
485 /// @endcond
486
487#if __cplusplus == 201703L && _GLIBCXX_USE_DEPRECATED
488# define _GLIBCXX_VOLATILE_BIND
489// _GLIBCXX_RESOLVE_LIB_DEFECTS
490// 2487. bind() should be const-overloaded, not cv-overloaded
491# define _GLIBCXX_DEPR_BIND \
492 [[deprecated("std::bind does not support volatile in C++17")]]
493#elif __cplusplus < 201703L
494# define _GLIBCXX_VOLATILE_BIND
495# define _GLIBCXX_DEPR_BIND
496#endif
497
498 /// Type of the function object returned from bind().
499 template<typename _Signature>
500 class _Bind;
501
502 template<typename _Functor, typename... _Bound_args>
503 class _Bind<_Functor(_Bound_args...)>
504 : public _Weak_result_type<_Functor>
505 {
506 typedef typename _Build_index_tuple<sizeof...(_Bound_args)>::__type
507 _Bound_indexes;
508
509 _Functor _M_f;
510 tuple<_Bound_args...> _M_bound_args;
511
512 // Call unqualified
513 template<typename _Result, typename... _Args, std::size_t... _Indexes>
514 _GLIBCXX20_CONSTEXPR
515 _Result
516 __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>)
517 {
518 return std::__invoke(_M_f,
519 _Mu<_Bound_args>()(std::get<_Indexes>(_M_bound_args), __args)...
520 );
521 }
522
523 // Call as const
524 template<typename _Result, typename... _Args, std::size_t... _Indexes>
525 _GLIBCXX20_CONSTEXPR
526 _Result
527 __call_c(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>) const
528 {
529 return std::__invoke(_M_f,
530 _Mu<_Bound_args>()(std::get<_Indexes>(_M_bound_args), __args)...
531 );
532 }
533
534#ifdef _GLIBCXX_VOLATILE_BIND
535 // Call as volatile
536 template<typename _Result, typename... _Args, std::size_t... _Indexes>
537 _Result
538 __call_v(tuple<_Args...>&& __args,
539 _Index_tuple<_Indexes...>) volatile
540 {
541 return std::__invoke(_M_f,
542 _Mu<_Bound_args>()(__volget<_Indexes>(_M_bound_args), __args)...
543 );
544 }
545
546 // Call as const volatile
547 template<typename _Result, typename... _Args, std::size_t... _Indexes>
548 _Result
549 __call_c_v(tuple<_Args...>&& __args,
550 _Index_tuple<_Indexes...>) const volatile
551 {
552 return std::__invoke(_M_f,
553 _Mu<_Bound_args>()(__volget<_Indexes>(_M_bound_args), __args)...
554 );
555 }
556#endif // volatile
557
558 template<typename _BoundArg, typename _CallArgs>
559 using _Mu_type = decltype(
560 _Mu<typename remove_cv<_BoundArg>::type>()(
561 std::declval<_BoundArg&>(), std::declval<_CallArgs&>()) );
562
563 template<typename _Fn, typename _CallArgs, typename... _BArgs>
564 using _Res_type_impl
565 = __invoke_result_t<_Fn&, _Mu_type<_BArgs, _CallArgs>&&...>;
566
567 template<typename _CallArgs>
568 using _Res_type = _Res_type_impl<_Functor, _CallArgs, _Bound_args...>;
569
570 template<typename _CallArgs>
571 using __dependent = typename
572 enable_if<bool(tuple_size<_CallArgs>::value+1), _Functor>::type;
573
574 template<typename _CallArgs, template<class> class __cv_quals>
575 using _Res_type_cv = _Res_type_impl<
576 typename __cv_quals<__dependent<_CallArgs>>::type,
577 _CallArgs,
578 typename __cv_quals<_Bound_args>::type...>;
579
580 public:
581 template<typename... _Args>
582 explicit _GLIBCXX20_CONSTEXPR
583 _Bind(const _Functor& __f, _Args&&... __args)
584 : _M_f(__f), _M_bound_args(std::forward<_Args>(__args)...)
585 { }
586
587 template<typename... _Args>
588 explicit _GLIBCXX20_CONSTEXPR
589 _Bind(_Functor&& __f, _Args&&... __args)
590 : _M_f(std::move(__f)), _M_bound_args(std::forward<_Args>(__args)...)
591 { }
592
593 _Bind(const _Bind&) = default;
594 _Bind(_Bind&&) = default;
595
596 // Call unqualified
597 template<typename... _Args,
598 typename _Result = _Res_type<tuple<_Args...>>>
599 _GLIBCXX20_CONSTEXPR
600 _Result
601 operator()(_Args&&... __args)
602 {
603 return this->__call<_Result>(
604 std::forward_as_tuple(std::forward<_Args>(__args)...),
605 _Bound_indexes());
606 }
607
608 // Call as const
609 template<typename... _Args,
610 typename _Result = _Res_type_cv<tuple<_Args...>, add_const>>
611 _GLIBCXX20_CONSTEXPR
612 _Result
613 operator()(_Args&&... __args) const
614 {
615 return this->__call_c<_Result>(
616 std::forward_as_tuple(std::forward<_Args>(__args)...),
617 _Bound_indexes());
618 }
619
620#ifdef _GLIBCXX_VOLATILE_BIND
621 // Call as volatile
622 template<typename... _Args,
623 typename _Result = _Res_type_cv<tuple<_Args...>, add_volatile>>
624 _GLIBCXX_DEPR_BIND
625 _Result
626 operator()(_Args&&... __args) volatile
627 {
628 return this->__call_v<_Result>(
629 std::forward_as_tuple(std::forward<_Args>(__args)...),
630 _Bound_indexes());
631 }
632
633 // Call as const volatile
634 template<typename... _Args,
635 typename _Result = _Res_type_cv<tuple<_Args...>, add_cv>>
636 _GLIBCXX_DEPR_BIND
637 _Result
638 operator()(_Args&&... __args) const volatile
639 {
640 return this->__call_c_v<_Result>(
641 std::forward_as_tuple(std::forward<_Args>(__args)...),
642 _Bound_indexes());
643 }
644#endif // volatile
645 };
646
647 /// Type of the function object returned from bind<R>().
648 template<typename _Result, typename _Signature>
649 class _Bind_result;
650
651 template<typename _Result, typename _Functor, typename... _Bound_args>
652 class _Bind_result<_Result, _Functor(_Bound_args...)>
653 {
654 typedef typename _Build_index_tuple<sizeof...(_Bound_args)>::__type
655 _Bound_indexes;
656
657 _Functor _M_f;
658 tuple<_Bound_args...> _M_bound_args;
659
660 // Call unqualified
661 template<typename _Res, typename... _Args, std::size_t... _Indexes>
662 _GLIBCXX20_CONSTEXPR
663 _Res
664 __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>)
665 {
666 return std::__invoke_r<_Res>(_M_f, _Mu<_Bound_args>()
667 (std::get<_Indexes>(_M_bound_args), __args)...);
668 }
669
670 // Call as const
671 template<typename _Res, typename... _Args, std::size_t... _Indexes>
672 _GLIBCXX20_CONSTEXPR
673 _Res
674 __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>) const
675 {
676 return std::__invoke_r<_Res>(_M_f, _Mu<_Bound_args>()
677 (std::get<_Indexes>(_M_bound_args), __args)...);
678 }
679
680#ifdef _GLIBCXX_VOLATILE_BIND
681 // Call as volatile
682 template<typename _Res, typename... _Args, std::size_t... _Indexes>
683 _Res
684 __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>) volatile
685 {
686 return std::__invoke_r<_Res>(_M_f, _Mu<_Bound_args>()
687 (__volget<_Indexes>(_M_bound_args), __args)...);
688 }
689
690 // Call as const volatile
691 template<typename _Res, typename... _Args, std::size_t... _Indexes>
692 _Res
693 __call(tuple<_Args...>&& __args,
694 _Index_tuple<_Indexes...>) const volatile
695 {
696 return std::__invoke_r<_Res>(_M_f, _Mu<_Bound_args>()
697 (__volget<_Indexes>(_M_bound_args), __args)...);
698 }
699#endif // volatile
700
701 public:
702 typedef _Result result_type;
703
704 template<typename... _Args>
705 explicit _GLIBCXX20_CONSTEXPR
706 _Bind_result(const _Functor& __f, _Args&&... __args)
707 : _M_f(__f), _M_bound_args(std::forward<_Args>(__args)...)
708 { }
709
710 template<typename... _Args>
711 explicit _GLIBCXX20_CONSTEXPR
712 _Bind_result(_Functor&& __f, _Args&&... __args)
713 : _M_f(std::move(__f)), _M_bound_args(std::forward<_Args>(__args)...)
714 { }
715
716 _Bind_result(const _Bind_result&) = default;
717 _Bind_result(_Bind_result&&) = default;
718
719 // Call unqualified
720 template<typename... _Args>
721 _GLIBCXX20_CONSTEXPR
722 result_type
723 operator()(_Args&&... __args)
724 {
725 return this->__call<_Result>(
726 std::forward_as_tuple(std::forward<_Args>(__args)...),
727 _Bound_indexes());
728 }
729
730 // Call as const
731 template<typename... _Args>
732 _GLIBCXX20_CONSTEXPR
733 result_type
734 operator()(_Args&&... __args) const
735 {
736 return this->__call<_Result>(
737 std::forward_as_tuple(std::forward<_Args>(__args)...),
738 _Bound_indexes());
739 }
740
741#ifdef _GLIBCXX_VOLATILE_BIND
742 // Call as volatile
743 template<typename... _Args>
744 _GLIBCXX_DEPR_BIND
745 result_type
746 operator()(_Args&&... __args) volatile
747 {
748 return this->__call<_Result>(
749 std::forward_as_tuple(std::forward<_Args>(__args)...),
750 _Bound_indexes());
751 }
752
753 // Call as const volatile
754 template<typename... _Args>
755 _GLIBCXX_DEPR_BIND
756 result_type
757 operator()(_Args&&... __args) const volatile
758 {
759 return this->__call<_Result>(
760 std::forward_as_tuple(std::forward<_Args>(__args)...),
761 _Bound_indexes());
762 }
763#else
764 template<typename... _Args>
765 void operator()(_Args&&...) const volatile = delete;
766#endif // volatile
767 };
768
769#undef _GLIBCXX_VOLATILE_BIND
770#undef _GLIBCXX_DEPR_BIND
771
772 /**
773 * @brief Class template _Bind is always a bind expression.
774 * @ingroup binders
775 */
776 template<typename _Signature>
777 struct is_bind_expression<_Bind<_Signature> >
778 : public true_type { };
779
780 /**
781 * @brief Class template _Bind is always a bind expression.
782 * @ingroup binders
783 */
784 template<typename _Signature>
785 struct is_bind_expression<const _Bind<_Signature> >
786 : public true_type { };
787
788 /**
789 * @brief Class template _Bind is always a bind expression.
790 * @ingroup binders
791 */
792 template<typename _Signature>
793 struct is_bind_expression<volatile _Bind<_Signature> >
794 : public true_type { };
795
796 /**
797 * @brief Class template _Bind is always a bind expression.
798 * @ingroup binders
799 */
800 template<typename _Signature>
801 struct is_bind_expression<const volatile _Bind<_Signature>>
802 : public true_type { };
803
804 /**
805 * @brief Class template _Bind_result is always a bind expression.
806 * @ingroup binders
807 */
808 template<typename _Result, typename _Signature>
809 struct is_bind_expression<_Bind_result<_Result, _Signature>>
810 : public true_type { };
811
812 /**
813 * @brief Class template _Bind_result is always a bind expression.
814 * @ingroup binders
815 */
816 template<typename _Result, typename _Signature>
817 struct is_bind_expression<const _Bind_result<_Result, _Signature>>
818 : public true_type { };
819
820 /**
821 * @brief Class template _Bind_result is always a bind expression.
822 * @ingroup binders
823 */
824 template<typename _Result, typename _Signature>
825 struct is_bind_expression<volatile _Bind_result<_Result, _Signature>>
826 : public true_type { };
827
828 /**
829 * @brief Class template _Bind_result is always a bind expression.
830 * @ingroup binders
831 */
832 template<typename _Result, typename _Signature>
833 struct is_bind_expression<const volatile _Bind_result<_Result, _Signature>>
834 : public true_type { };
835
836 template<typename _Func, typename... _BoundArgs>
837 struct _Bind_check_arity { };
838
839 template<typename _Ret, typename... _Args, typename... _BoundArgs>
840 struct _Bind_check_arity<_Ret (*)(_Args...), _BoundArgs...>
841 {
842 static_assert(sizeof...(_BoundArgs) == sizeof...(_Args),
843 "Wrong number of arguments for function");
844 };
845
846 template<typename _Ret, typename... _Args, typename... _BoundArgs>
847 struct _Bind_check_arity<_Ret (*)(_Args..., ...), _BoundArgs...>
848 {
849 static_assert(sizeof...(_BoundArgs) >= sizeof...(_Args),
850 "Wrong number of arguments for function");
851 };
852
853 template<typename _Tp, typename _Class, typename... _BoundArgs>
854 struct _Bind_check_arity<_Tp _Class::*, _BoundArgs...>
855 {
856 using _Arity = typename _Mem_fn<_Tp _Class::*>::_Arity;
857 using _Varargs = typename _Mem_fn<_Tp _Class::*>::_Varargs;
858 static_assert(_Varargs::value
859 ? sizeof...(_BoundArgs) >= _Arity::value + 1
860 : sizeof...(_BoundArgs) == _Arity::value + 1,
861 "Wrong number of arguments for pointer-to-member");
862 };
863
864 // Trait type used to remove std::bind() from overload set via SFINAE
865 // when first argument has integer type, so that std::bind() will
866 // not be a better match than ::bind() from the BSD Sockets API.
867 template<typename _Tp, typename _Tp2 = typename decay<_Tp>::type>
868 using __is_socketlike = __or_<is_integral<_Tp2>, is_enum<_Tp2>>;
869
870 template<bool _SocketLike, typename _Func, typename... _BoundArgs>
871 struct _Bind_helper
872 : _Bind_check_arity<typename decay<_Func>::type, _BoundArgs...>
873 {
874 typedef typename decay<_Func>::type __func_type;
875 typedef _Bind<__func_type(typename decay<_BoundArgs>::type...)> type;
876 };
877
878 // Partial specialization for is_socketlike == true, does not define
879 // nested type so std::bind() will not participate in overload resolution
880 // when the first argument might be a socket file descriptor.
881 template<typename _Func, typename... _BoundArgs>
882 struct _Bind_helper<true, _Func, _BoundArgs...>
883 { };
884
885 /**
886 * @brief Function template for std::bind.
887 * @ingroup binders
888 * @since C++11
889 */
890 template<typename _Func, typename... _BoundArgs>
891 inline _GLIBCXX20_CONSTEXPR typename
892 _Bind_helper<__is_socketlike<_Func>::value, _Func, _BoundArgs...>::type
893 bind(_Func&& __f, _BoundArgs&&... __args)
894 {
895 typedef _Bind_helper<false, _Func, _BoundArgs...> __helper_type;
896 return typename __helper_type::type(std::forward<_Func>(__f),
897 std::forward<_BoundArgs>(__args)...);
898 }
899
900 template<typename _Result, typename _Func, typename... _BoundArgs>
901 struct _Bindres_helper
902 : _Bind_check_arity<typename decay<_Func>::type, _BoundArgs...>
903 {
904 typedef typename decay<_Func>::type __functor_type;
905 typedef _Bind_result<_Result,
906 __functor_type(typename decay<_BoundArgs>::type...)>
907 type;
908 };
909
910 /**
911 * @brief Function template for std::bind<R>.
912 * @ingroup binders
913 * @since C++11
914 */
915 template<typename _Result, typename _Func, typename... _BoundArgs>
916 inline _GLIBCXX20_CONSTEXPR
917 typename _Bindres_helper<_Result, _Func, _BoundArgs...>::type
918 bind(_Func&& __f, _BoundArgs&&... __args)
919 {
920 typedef _Bindres_helper<_Result, _Func, _BoundArgs...> __helper_type;
921 return typename __helper_type::type(std::forward<_Func>(__f),
922 std::forward<_BoundArgs>(__args)...);
923 }
924
925#if __cpp_lib_bind_front >= 202306L || __cpp_lib_bind_back >= 202306L
926 template <auto __fn>
927 struct _Bind_fn_t
928 {
929 using _Fn = const decltype(__fn)&;
930 template <typename... _Args>
931 constexpr static decltype(auto)
932 operator()(_Args... __args)
933 noexcept(is_nothrow_invocable_v<_Fn, _Args...>)
934 requires is_invocable_v<_Fn, _Args...>
935 { return std::invoke(__fn, std::forward<_Args>(__args)...); }
936 };
937#endif
938
939#ifdef __cpp_lib_bind_front // C++ >= 20
940 /** Create call wrapper by partial application of arguments to function.
941 *
942 * The result of `std::bind_front(f, args...)` is a function object that
943 * stores `f` and the bound arguments, `args...`. When that function
944 * object is invoked with `call_args...` it returns the result of calling
945 * `f(args..., call_args...)`.
946 *
947 * @since C++20
948 */
949 template<typename _Fn, typename... _Args>
950 constexpr _Bind_front_t<_Fn, _Args...>
951 bind_front(_Fn&& __fn, _Args&&... __args)
952 noexcept(is_nothrow_constructible_v<_Bind_front_t<_Fn, _Args...>,
953 int, _Fn, _Args...>)
954 {
955 return _Bind_front_t<_Fn, _Args...>(0, std::forward<_Fn>(__fn),
956 std::forward<_Args>(__args)...);
957 }
958
959#if __cpp_lib_bind_front >= 202306L
960
961 /** Create call wrapper by partial application of arguments to function.
962 *
963 * The result of `std::bind_front<fn>(bind_args...)` is a function object
964 * that stores the bound arguments, `bind_args...`. When that function
965 * object is invoked with `call_args...` it returns the result of calling
966 * `fn(bind_args..., call_args...)`.
967 *
968 * @since C++26
969 */
970 template<auto __fn, typename... _BindArgs>
971 constexpr decltype(auto)
972 bind_front(_BindArgs&&... __bind_args)
973 noexcept(__and_v<is_nothrow_constructible<_BindArgs>...>)
974 {
975 using _Fn = decltype(__fn);
976 static_assert(
977 (is_constructible_v<decay_t<_BindArgs>, _BindArgs> && ...) &&
978 (is_move_constructible_v<decay_t<_BindArgs>> && ...));
979 if constexpr (is_pointer_v<_Fn> || is_member_pointer_v<_Fn>)
980 static_assert(__fn != nullptr);
981
982 if constexpr (sizeof...(_BindArgs) == 0)
983 return _Bind_fn_t<__fn>{};
984 else {
985 return [... __bound_args(std::forward<_BindArgs>(__bind_args))]
986 <typename _Self, typename... _CallArgs>
987 (this _Self&&, _CallArgs&&... __call_args)
988 noexcept(is_nothrow_invocable_v<
989 const _Fn&, __like_t<_Self, decay_t<_BindArgs>>..., _CallArgs...>)
990 -> decltype(auto)
991 requires is_invocable_v<
992 const _Fn&, __like_t<_Self, decay_t<_BindArgs>>..., _CallArgs...>
993 {
994 return std::invoke(__fn,
995 std::forward_like<_Self>(__bound_args)...,
996 std::forward<_CallArgs>(__call_args)...);
997 };
998 }
999 }
1000
1001#endif // __cpp_lib_bind_front // C++26
1002#endif // __cpp_lib_bind_front
1003
1004#ifdef __cpp_lib_bind_back // C++ >= 23
1005 /** Create call wrapper by partial application of arguments to function.
1006 *
1007 * The result of `std::bind_back(f, args...)` is a function object that
1008 * stores `f` and the bound arguments, `args...`. When that function
1009 * object is invoked with `call_args...` it returns the result of calling
1010 * `f(call_args..., args...)`.
1011 *
1012 * @since C++23
1013 */
1014 template<typename _Fn, typename... _Args>
1015 constexpr _Bind_back_t<_Fn, _Args...>
1016 bind_back(_Fn&& __fn, _Args&&... __args)
1017 noexcept(is_nothrow_constructible_v<_Bind_back_t<_Fn, _Args...>,
1018 int, _Fn, _Args...>)
1019 {
1020 return _Bind_back_t<_Fn, _Args...>(0, std::forward<_Fn>(__fn),
1021 std::forward<_Args>(__args)...);
1022 }
1023
1024#if __cpp_lib_bind_back >= 202306L
1025
1026 /** Create call wrapper by partial application of arguments to function.
1027 *
1028 * The result of `std::bind_back<fn>(bind_args...)` is a function object
1029 * that stores the arguments, `bind_args...`. When that function object
1030 * is invoked with `call_args...` it returns the result of calling
1031 * `fn(call_args..., bind_args...)`.
1032 *
1033 * @since C++26
1034 */
1035 template<auto __fn, typename... _BindArgs>
1036 constexpr decltype(auto)
1037 bind_back(_BindArgs&&... __bind_args)
1038 noexcept(__and_v<is_nothrow_constructible<_BindArgs>...>)
1039 {
1040 using _Fn = decltype(__fn);
1041 static_assert(
1042 (is_constructible_v<decay_t<_BindArgs>, _BindArgs> && ...) &&
1043 (is_move_constructible_v<decay_t<_BindArgs>> && ...));
1044 if constexpr (is_pointer_v<_Fn> || is_member_pointer_v<_Fn>)
1045 static_assert(__fn != nullptr);
1046
1047 if constexpr (sizeof...(_BindArgs) == 0)
1048 return _Bind_fn_t<__fn>{};
1049 else
1050 {
1051 // Capture arguments in a lambda and return that.
1052 return [... __bound_args(std::forward<_BindArgs>(__bind_args))]
1053 <typename _Self, typename... _CallArgs>
1054 (this _Self&&, _CallArgs&&... __call_args)
1055 noexcept(is_nothrow_invocable_v<
1056 const _Fn&, _CallArgs..., __like_t<_Self, decay_t<_BindArgs>>...>)
1057 -> decltype(auto)
1058 requires is_invocable_v<
1059 const _Fn&, _CallArgs..., __like_t<_Self, decay_t<_BindArgs>>...>
1060 {
1061 return std::invoke(__fn,
1062 std::forward<_CallArgs>(__call_args)...,
1063 std::forward_like<_Self>(__bound_args)...);
1064 };
1065 }
1066 }
1067
1068#endif // __cpp_lib_bind_back // C++26, nttp
1069#endif // __cpp_lib_bind_back
1070
1071#if __cplusplus >= 201402L
1072 /// Generalized negator.
1073 template<typename _Fn>
1074 class _Not_fn
1075 {
1076 template<typename _Fn2, typename... _Args>
1077 using __inv_res_t = typename __invoke_result<_Fn2, _Args...>::type;
1078
1079 template<typename _Tp>
1080 static decltype(!std::declval<_Tp>())
1081 _S_not() noexcept(noexcept(!std::declval<_Tp>()));
1082
1083 public:
1084 template<typename _Fn2>
1085 constexpr
1086 _Not_fn(_Fn2&& __fn, int)
1087 : _M_fn(std::forward<_Fn2>(__fn)) { }
1088
1089 _Not_fn(const _Not_fn& __fn) = default;
1090 _Not_fn(_Not_fn&& __fn) = default;
1091 ~_Not_fn() = default;
1092
1093 // Macro to define operator() with given cv-qualifiers ref-qualifiers,
1094 // forwarding _M_fn and the function arguments with the same qualifiers,
1095 // and deducing the return type and exception-specification.
1096#define _GLIBCXX_NOT_FN_CALL_OP( _QUALS ) \
1097 template<typename... _Args, \
1098 typename = enable_if_t<__is_invocable<_Fn _QUALS, _Args...>::value>> \
1099 _GLIBCXX20_CONSTEXPR \
1100 decltype(_S_not<__inv_res_t<_Fn _QUALS, _Args...>>()) \
1101 operator()(_Args&&... __args) _QUALS \
1102 noexcept(__is_nothrow_invocable<_Fn _QUALS, _Args...>::value \
1103 && noexcept(_S_not<__inv_res_t<_Fn _QUALS, _Args...>>())) \
1104 { \
1105 return !std::__invoke(std::forward< _Fn _QUALS >(_M_fn), \
1106 std::forward<_Args>(__args)...); \
1107 } \
1108 \
1109 template<typename... _Args, \
1110 typename = enable_if_t<!__is_invocable<_Fn _QUALS, _Args...>::value>> \
1111 void operator()(_Args&&... __args) _QUALS = delete;
1112
1113 _GLIBCXX_NOT_FN_CALL_OP( & )
1114 _GLIBCXX_NOT_FN_CALL_OP( const & )
1115 _GLIBCXX_NOT_FN_CALL_OP( && )
1116 _GLIBCXX_NOT_FN_CALL_OP( const && )
1117#undef _GLIBCXX_NOT_FN_CALL_OP
1118
1119 private:
1120 _Fn _M_fn;
1121 };
1122
1123 template<typename _Tp, typename _Pred>
1124 struct __is_byte_like : false_type { };
1125
1126 template<typename _Tp>
1127 struct __is_byte_like<_Tp, equal_to<_Tp>>
1128 : __bool_constant<sizeof(_Tp) == 1 && is_integral<_Tp>::value> { };
1129
1130 template<typename _Tp>
1131 struct __is_byte_like<_Tp, equal_to<void>>
1132 : __bool_constant<sizeof(_Tp) == 1 && is_integral<_Tp>::value> { };
1133
1134#if __cplusplus >= 201703L
1135 // Declare std::byte (full definition is in <cstddef>).
1136 enum class byte : unsigned char;
1137
1138 template<>
1139 struct __is_byte_like<byte, equal_to<byte>>
1140 : true_type { };
1141
1142 template<>
1143 struct __is_byte_like<byte, equal_to<void>>
1144 : true_type { };
1145#endif
1146
1147 // [func.not_fn] Function template not_fn
1148#ifdef __cpp_lib_not_fn // C++ >= 17
1149 /** Wrap a function object to create one that negates its result.
1150 *
1151 * The function template `std::not_fn` creates a "forwarding call wrapper",
1152 * which is a function object that wraps another function object and
1153 * when called, forwards its arguments to the wrapped function object.
1154 *
1155 * The result of invoking the wrapper is the negation (using `!`) of
1156 * the wrapped function object.
1157 *
1158 * @ingroup functors
1159 * @since C++17
1160 */
1161 template<typename _Fn>
1162 _GLIBCXX20_CONSTEXPR
1163 inline auto
1164 not_fn(_Fn&& __fn)
1165 noexcept(std::is_nothrow_constructible<std::decay_t<_Fn>, _Fn&&>::value)
1166 {
1167 return _Not_fn<std::decay_t<_Fn>>{std::forward<_Fn>(__fn), 0};
1168 }
1169
1170#if __cpp_lib_not_fn >= 202306L
1171
1172 /** Wrap a function type to create a function object that negates its result.
1173 *
1174 * The function template `std::not_fn` creates a "forwarding call wrapper",
1175 * which is a function object that when called forwards its arguments to
1176 * its invocable template argument.
1177 *
1178 * The result of invoking the wrapper is the negation (using `!`) of
1179 * the wrapped function object.
1180 *
1181 * @ingroup functors
1182 * @since C++26
1183 */
1184 template<auto __fn>
1185 constexpr decltype(auto)
1186 not_fn() noexcept
1187 {
1188 using _Fn = decltype(__fn);
1189 if constexpr (is_pointer_v<_Fn> || is_member_pointer_v<_Fn>)
1190 static_assert(__fn != nullptr);
1191 return []<typename... _Args>(_Args... __args) static
1192 noexcept(noexcept(
1193 !std::invoke(__fn, std::forward<_Args>(__args)...) ))
1194 -> decltype(auto)
1195 requires requires {
1196 !std::invoke(__fn, std::forward<_Args>(__args)...); }
1197 { return !std::invoke(__fn, std::forward<_Args>(__args)...); };
1198 };
1199
1200#endif // __cpp_lib_not_fn >= 202306L
1201#endif // __cpp_lib_not_fn
1202
1203#if __cplusplus >= 201703L
1204 // Searchers
1205
1206 template<typename _ForwardIterator1, typename _BinaryPredicate = equal_to<>>
1207 class default_searcher
1208 {
1209 public:
1210 _GLIBCXX20_CONSTEXPR
1211 default_searcher(_ForwardIterator1 __pat_first,
1212 _ForwardIterator1 __pat_last,
1213 _BinaryPredicate __pred = _BinaryPredicate())
1214 : _M_m(__pat_first, __pat_last, std::move(__pred))
1215 { }
1216
1217 template<typename _ForwardIterator2>
1218 _GLIBCXX20_CONSTEXPR
1219 pair<_ForwardIterator2, _ForwardIterator2>
1220 operator()(_ForwardIterator2 __first, _ForwardIterator2 __last) const
1221 {
1222 _ForwardIterator2 __first_ret =
1223 std::search(__first, __last, std::get<0>(_M_m), std::get<1>(_M_m),
1224 std::get<2>(_M_m));
1225 auto __ret = std::make_pair(__first_ret, __first_ret);
1226 if (__ret.first != __last)
1227 std::advance(__ret.second, std::distance(std::get<0>(_M_m),
1228 std::get<1>(_M_m)));
1229 return __ret;
1230 }
1231
1232 private:
1233 tuple<_ForwardIterator1, _ForwardIterator1, _BinaryPredicate> _M_m;
1234 };
1235
1236#ifdef __cpp_lib_boyer_moore_searcher // C++ >= 17 && HOSTED
1237
1238 template<typename _Key, typename _Tp, typename _Hash, typename _Pred>
1239 struct __boyer_moore_map_base
1240 {
1241 template<typename _RAIter>
1242 __boyer_moore_map_base(_RAIter __pat, size_t __patlen,
1243 _Hash&& __hf, _Pred&& __pred)
1244 : _M_bad_char{ __patlen, std::move(__hf), std::move(__pred) }
1245 {
1246 if (__patlen > 0)
1247 for (__diff_type __i = 0; __i < __patlen - 1; ++__i)
1248 _M_bad_char[__pat[__i]] = __patlen - 1 - __i;
1249 }
1250
1251 using __diff_type = _Tp;
1252
1253 __diff_type
1254 _M_lookup(_Key __key, __diff_type __not_found) const
1255 {
1256 auto __iter = _M_bad_char.find(__key);
1257 if (__iter == _M_bad_char.end())
1258 return __not_found;
1259 return __iter->second;
1260 }
1261
1262 _Pred
1263 _M_pred() const { return _M_bad_char.key_eq(); }
1264
1265 _GLIBCXX_STD_C::unordered_map<_Key, _Tp, _Hash, _Pred> _M_bad_char;
1266 };
1267
1268 template<typename _Tp, size_t _Len, typename _Pred>
1269 struct __boyer_moore_array_base
1270 {
1271 template<typename _RAIter, typename _Unused>
1272 __boyer_moore_array_base(_RAIter __pat, size_t __patlen,
1273 _Unused&&, _Pred&& __pred)
1274 : _M_bad_char{ array<_Tp, _Len>{}, std::move(__pred) }
1275 {
1276 std::get<0>(_M_bad_char).fill(__patlen);
1277 if (__patlen > 0)
1278 for (__diff_type __i = 0; __i < __patlen - 1; ++__i)
1279 {
1280 auto __ch = __pat[__i];
1281 using _UCh = make_unsigned_t<decltype(__ch)>;
1282 auto __uch = static_cast<_UCh>(__ch);
1283 std::get<0>(_M_bad_char)[__uch] = __patlen - 1 - __i;
1284 }
1285 }
1286
1287 using __diff_type = _Tp;
1288
1289 template<typename _Key>
1290 __diff_type
1291 _M_lookup(_Key __key, __diff_type __not_found) const
1292 {
1293 auto __ukey = static_cast<make_unsigned_t<_Key>>(__key);
1294 if (__ukey >= _Len)
1295 return __not_found;
1296 return std::get<0>(_M_bad_char)[__ukey];
1297 }
1298
1299 const _Pred&
1300 _M_pred() const { return std::get<1>(_M_bad_char); }
1301
1302 tuple<array<_Tp, _Len>, _Pred> _M_bad_char;
1303 };
1304
1305 // Use __boyer_moore_array_base when pattern consists of narrow characters
1306 // (or std::byte) and uses std::equal_to as the predicate.
1307 template<typename _RAIter, typename _Hash, typename _Pred,
1308 typename _Val = typename iterator_traits<_RAIter>::value_type,
1309 typename _Diff = typename iterator_traits<_RAIter>::difference_type>
1310 using __boyer_moore_base_t
1311 = __conditional_t<__is_byte_like<_Val, _Pred>::value,
1312 __boyer_moore_array_base<_Diff, 256, _Pred>,
1313 __boyer_moore_map_base<_Val, _Diff, _Hash, _Pred>>;
1314
1315 template<typename _RAIter, typename _Hash
1316 = hash<typename iterator_traits<_RAIter>::value_type>,
1317 typename _BinaryPredicate = equal_to<>>
1318 class boyer_moore_searcher
1319 : __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>
1320 {
1321 using _Base = __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>;
1322 using typename _Base::__diff_type;
1323
1324 public:
1325 boyer_moore_searcher(_RAIter __pat_first, _RAIter __pat_last,
1326 _Hash __hf = _Hash(),
1327 _BinaryPredicate __pred = _BinaryPredicate());
1328
1329 template<typename _RandomAccessIterator2>
1330 pair<_RandomAccessIterator2, _RandomAccessIterator2>
1331 operator()(_RandomAccessIterator2 __first,
1332 _RandomAccessIterator2 __last) const;
1333
1334 private:
1335 bool
1336 _M_is_prefix(_RAIter __word, __diff_type __len,
1337 __diff_type __pos)
1338 {
1339 const auto& __pred = this->_M_pred();
1340 __diff_type __suffixlen = __len - __pos;
1341 for (__diff_type __i = 0; __i < __suffixlen; ++__i)
1342 if (!__pred(__word[__i], __word[__pos + __i]))
1343 return false;
1344 return true;
1345 }
1346
1347 __diff_type
1348 _M_suffix_length(_RAIter __word, __diff_type __len,
1349 __diff_type __pos)
1350 {
1351 const auto& __pred = this->_M_pred();
1352 __diff_type __i = 0;
1353 while (__pred(__word[__pos - __i], __word[__len - 1 - __i])
1354 && __i < __pos)
1355 {
1356 ++__i;
1357 }
1358 return __i;
1359 }
1360
1361 template<typename _Tp>
1362 __diff_type
1363 _M_bad_char_shift(_Tp __c) const
1364 { return this->_M_lookup(__c, _M_pat_end - _M_pat); }
1365
1366 _RAIter _M_pat;
1367 _RAIter _M_pat_end;
1368 _GLIBCXX_STD_C::vector<__diff_type> _M_good_suffix;
1369 };
1370
1371 template<typename _RAIter, typename _Hash
1372 = hash<typename iterator_traits<_RAIter>::value_type>,
1373 typename _BinaryPredicate = equal_to<>>
1374 class boyer_moore_horspool_searcher
1375 : __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>
1376 {
1377 using _Base = __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>;
1378 using typename _Base::__diff_type;
1379
1380 public:
1381 boyer_moore_horspool_searcher(_RAIter __pat,
1382 _RAIter __pat_end,
1383 _Hash __hf = _Hash(),
1384 _BinaryPredicate __pred
1385 = _BinaryPredicate())
1386 : _Base(__pat, __pat_end - __pat, std::move(__hf), std::move(__pred)),
1387 _M_pat(__pat), _M_pat_end(__pat_end)
1388 { }
1389
1390 template<typename _RandomAccessIterator2>
1391 pair<_RandomAccessIterator2, _RandomAccessIterator2>
1392 operator()(_RandomAccessIterator2 __first,
1393 _RandomAccessIterator2 __last) const
1394 {
1395#ifdef __glibcxx_concepts // >= C++20
1396 // Value types must be the same for hash function and predicate
1397 // to give consistent results for lookup in the map.
1398 static_assert(is_same_v<iter_value_t<_RAIter>,
1399 iter_value_t<_RandomAccessIterator2>>);
1400#endif
1401 const auto& __pred = this->_M_pred();
1402 auto __patlen = _M_pat_end - _M_pat;
1403 if (__patlen == 0)
1404 return std::make_pair(__first, __first);
1405 auto __len = __last - __first;
1406 while (__len >= __patlen)
1407 {
1408 for (auto __scan = __patlen - 1;
1409 __pred(__first[__scan], _M_pat[__scan]); --__scan)
1410 if (__scan == 0)
1411 return std::make_pair(__first, __first + __patlen);
1412 auto __shift = _M_bad_char_shift(__first[__patlen - 1]);
1413 __len -= __shift;
1414 __first += __shift;
1415 }
1416 return std::make_pair(__last, __last);
1417 }
1418
1419 private:
1420 template<typename _Tp>
1421 __diff_type
1422 _M_bad_char_shift(_Tp __c) const
1423 { return this->_M_lookup(__c, _M_pat_end - _M_pat); }
1424
1425 _RAIter _M_pat;
1426 _RAIter _M_pat_end;
1427 };
1428
1429 template<typename _RAIter, typename _Hash, typename _BinaryPredicate>
1430 boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>::
1431 boyer_moore_searcher(_RAIter __pat, _RAIter __pat_end,
1432 _Hash __hf, _BinaryPredicate __pred)
1433 : _Base(__pat, __pat_end - __pat, std::move(__hf), std::move(__pred)),
1434 _M_pat(__pat), _M_pat_end(__pat_end), _M_good_suffix(__pat_end - __pat)
1435 {
1436 auto __patlen = __pat_end - __pat;
1437 if (__patlen == 0)
1438 return;
1439 __diff_type __last_prefix = __patlen - 1;
1440 for (__diff_type __p = __patlen - 1; __p >= 0; --__p)
1441 {
1442 if (_M_is_prefix(__pat, __patlen, __p + 1))
1443 __last_prefix = __p + 1;
1444 _M_good_suffix[__p] = __last_prefix + (__patlen - 1 - __p);
1445 }
1446 for (__diff_type __p = 0; __p < __patlen - 1; ++__p)
1447 {
1448 auto __slen = _M_suffix_length(__pat, __patlen, __p);
1449 auto __pos = __patlen - 1 - __slen;
1450 if (!__pred(__pat[__p - __slen], __pat[__pos]))
1451 _M_good_suffix[__pos] = __patlen - 1 - __p + __slen;
1452 }
1453 }
1454
1455 template<typename _RAIter, typename _Hash, typename _BinaryPredicate>
1456 template<typename _RandomAccessIterator2>
1457 pair<_RandomAccessIterator2, _RandomAccessIterator2>
1458 boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>::
1459 operator()(_RandomAccessIterator2 __first,
1460 _RandomAccessIterator2 __last) const
1461 {
1462#ifdef __glibcxx_concepts // >= C++20
1463 // Value types must be the same for hash function and predicate
1464 // to give consistent results for lookup in the map.
1465 static_assert(is_same_v<iter_value_t<_RAIter>,
1466 iter_value_t<_RandomAccessIterator2>>);
1467#endif
1468 auto __patlen = _M_pat_end - _M_pat;
1469 if (__patlen == 0)
1470 return std::make_pair(__first, __first);
1471 const auto& __pred = this->_M_pred();
1472 __diff_type __i = __patlen - 1;
1473 auto __stringlen = __last - __first;
1474 while (__i < __stringlen)
1475 {
1476 __diff_type __j = __patlen - 1;
1477 while (__j >= 0 && __pred(__first[__i], _M_pat[__j]))
1478 {
1479 --__i;
1480 --__j;
1481 }
1482 if (__j < 0)
1483 {
1484 const auto __match = __first + __diff_type(__i + 1);
1485 return std::make_pair(__match, __match + __patlen);
1486 }
1487 __i += std::max(_M_bad_char_shift(__first[__i]),
1488 _M_good_suffix[__j]);
1489 }
1490 return std::make_pair(__last, __last);
1491 }
1492#endif // __cpp_lib_boyer_moore_searcher
1493
1494#endif // C++17
1495#endif // C++14
1496#endif // C++11
1497
1498_GLIBCXX_END_NAMESPACE_VERSION
1499} // namespace std
1500
1501#endif // _GLIBCXX_FUNCTIONAL