libstdc++
functional
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1 // <functional> -*- C++ -*-
2 
3 // Copyright (C) 2001-2024 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 #pragma GCC system_header
47 
48 #include <bits/c++config.h>
49 #include <bits/stl_function.h> // std::equal_to, std::unary_function etc.
50 
51 #if __cplusplus >= 201103L
52 
53 #include <tuple>
54 #include <type_traits>
55 #include <bits/functional_hash.h>
56 #include <bits/invoke.h>
57 #include <bits/refwrap.h> // std::reference_wrapper and _Mem_fn_traits
58 #if _GLIBCXX_HOSTED
59 # include <bits/std_function.h> // std::function
60 #endif
61 #if __cplusplus >= 201703L
62 # if _GLIBCXX_HOSTED
63 # include <unordered_map>
64 # include <vector>
65 # include <array>
66 # endif
67 # include <bits/stl_algobase.h> // std::search
68 #endif
69 #if __cplusplus >= 202002L
70 # include <bits/ranges_cmp.h> // std::identity, ranges::equal_to etc.
71 # include <compare>
72 #endif
73 #if __cplusplus > 202002L && _GLIBCXX_HOSTED
74 # include <bits/move_only_function.h>
75 #endif
76 
77 #define __glibcxx_want_boyer_moore_searcher
78 #define __glibcxx_want_bind_front
79 #define __glibcxx_want_bind_back
80 #define __glibcxx_want_constexpr_functional
81 #define __glibcxx_want_invoke
82 #define __glibcxx_want_invoke_r
83 #define __glibcxx_want_move_only_function
84 #define __glibcxx_want_not_fn
85 #define __glibcxx_want_ranges
86 #define __glibcxx_want_reference_wrapper
87 #define __glibcxx_want_transparent_operators
88 #include <bits/version.h>
89 
90 #endif // C++11
91 
92 namespace std _GLIBCXX_VISIBILITY(default)
93 {
94 _GLIBCXX_BEGIN_NAMESPACE_VERSION
95 
96  /** @brief The type of placeholder objects defined by libstdc++.
97  * @ingroup binders
98  * @since C++11
99  */
100  template<int _Num> struct _Placeholder { };
101 
102 #ifdef __cpp_lib_invoke // C++ >= 17
103 
104  /** Invoke a callable object.
105  *
106  * `std::invoke` takes a callable object as its first argument and calls it
107  * with the remaining arguments. The callable object can be a pointer or
108  * reference to a function, a lambda closure, a class with `operator()`,
109  * or even a pointer-to-member. For a pointer-to-member the first argument
110  * must be a reference or pointer to the object that the pointer-to-member
111  * will be applied to.
112  *
113  * @since C++17
114  */
115  template<typename _Callable, typename... _Args>
116  inline _GLIBCXX20_CONSTEXPR invoke_result_t<_Callable, _Args...>
117  invoke(_Callable&& __fn, _Args&&... __args)
118  noexcept(is_nothrow_invocable_v<_Callable, _Args...>)
119  {
120  return std::__invoke(std::forward<_Callable>(__fn),
121  std::forward<_Args>(__args)...);
122  }
123 #endif
124 
125 #ifdef __cpp_lib_invoke_r // C++ >= 23
126 
127  /** Invoke a callable object and convert the result to `_Res`.
128  *
129  * `std::invoke_r<R>(f, args...)` is equivalent to `std::invoke(f, args...)`
130  * with the result implicitly converted to `R`.
131  *
132  * @since C++23
133  */
134  template<typename _Res, typename _Callable, typename... _Args>
135  requires is_invocable_r_v<_Res, _Callable, _Args...>
136  constexpr _Res
137  invoke_r(_Callable&& __fn, _Args&&... __args)
138  noexcept(is_nothrow_invocable_r_v<_Res, _Callable, _Args...>)
139  {
140  return std::__invoke_r<_Res>(std::forward<_Callable>(__fn),
141  std::forward<_Args>(__args)...);
142  }
143 #endif // __cpp_lib_invoke_r
144 
145  /// @cond undocumented
146 
147 #if __cplusplus >= 201103L
148  template<typename _MemFunPtr,
149  bool __is_mem_fn = is_member_function_pointer<_MemFunPtr>::value>
150  class _Mem_fn_base
151  : public _Mem_fn_traits<_MemFunPtr>::__maybe_type
152  {
153  using _Traits = _Mem_fn_traits<_MemFunPtr>;
154 
155  using _Arity = typename _Traits::__arity;
156  using _Varargs = typename _Traits::__vararg;
157 
158  template<typename _Func, typename... _BoundArgs>
159  friend struct _Bind_check_arity;
160 
161  _MemFunPtr _M_pmf;
162 
163  public:
164 
165  using result_type = typename _Traits::__result_type;
166 
167  explicit constexpr
168  _Mem_fn_base(_MemFunPtr __pmf) noexcept : _M_pmf(__pmf) { }
169 
170  template<typename... _Args>
171  _GLIBCXX20_CONSTEXPR
172  auto
173  operator()(_Args&&... __args) const
174  noexcept(noexcept(
175  std::__invoke(_M_pmf, std::forward<_Args>(__args)...)))
176  -> decltype(std::__invoke(_M_pmf, std::forward<_Args>(__args)...))
177  { return std::__invoke(_M_pmf, std::forward<_Args>(__args)...); }
178  };
179 
180  // Partial specialization for member object pointers.
181  template<typename _MemObjPtr>
182  class _Mem_fn_base<_MemObjPtr, false>
183  {
184  using _Arity = integral_constant<size_t, 0>;
185  using _Varargs = false_type;
186 
187  template<typename _Func, typename... _BoundArgs>
188  friend struct _Bind_check_arity;
189 
190  _MemObjPtr _M_pm;
191 
192  public:
193  explicit constexpr
194  _Mem_fn_base(_MemObjPtr __pm) noexcept : _M_pm(__pm) { }
195 
196  template<typename _Tp>
197  _GLIBCXX20_CONSTEXPR
198  auto
199  operator()(_Tp&& __obj) const
200  noexcept(noexcept(std::__invoke(_M_pm, std::forward<_Tp>(__obj))))
201  -> decltype(std::__invoke(_M_pm, std::forward<_Tp>(__obj)))
202  { return std::__invoke(_M_pm, std::forward<_Tp>(__obj)); }
203  };
204 
205  template<typename _MemberPointer>
206  struct _Mem_fn; // undefined
207 
208  template<typename _Res, typename _Class>
209  struct _Mem_fn<_Res _Class::*>
210  : _Mem_fn_base<_Res _Class::*>
211  {
212  using _Mem_fn_base<_Res _Class::*>::_Mem_fn_base;
213  };
214  /// @endcond
215 
216  // _GLIBCXX_RESOLVE_LIB_DEFECTS
217  // 2048. Unnecessary mem_fn overloads
218  /**
219  * @brief Returns a function object that forwards to the member pointer
220  * pointer `pm`.
221  *
222  * This allows a pointer-to-member to be transformed into a function object
223  * that can be called with an object expression as its first argument.
224  *
225  * For a pointer-to-data-member the result must be called with exactly one
226  * argument, the object expression that would be used as the first operand
227  * in a `obj.*memptr` or `objp->*memptr` expression.
228  *
229  * For a pointer-to-member-function the result must be called with an object
230  * expression and any additional arguments to pass to the member function,
231  * as in an expression like `(obj.*memfun)(args...)` or
232  * `(objp->*memfun)(args...)`.
233  *
234  * The object expression can be a pointer, reference, `reference_wrapper`,
235  * or smart pointer, and the call wrapper will dereference it as needed
236  * to apply the pointer-to-member.
237  *
238  * @ingroup functors
239  * @since C++11
240  */
241  template<typename _Tp, typename _Class>
242  _GLIBCXX20_CONSTEXPR
243  inline _Mem_fn<_Tp _Class::*>
244  mem_fn(_Tp _Class::* __pm) noexcept
245  {
246  return _Mem_fn<_Tp _Class::*>(__pm);
247  }
248 
249  /**
250  * @brief Trait that identifies a bind expression.
251  *
252  * Determines if the given type `_Tp` is a function object that
253  * should be treated as a subexpression when evaluating calls to
254  * function objects returned by `std::bind`.
255  *
256  * C++11 [func.bind.isbind].
257  * @ingroup binders
258  * @since C++11
259  */
260  template<typename _Tp>
261  struct is_bind_expression
262  : public false_type { };
263 
264  /**
265  * @brief Determines if the given type _Tp is a placeholder in a
266  * bind() expression and, if so, which placeholder it is.
267  *
268  * C++11 [func.bind.isplace].
269  * @ingroup binders
270  * @since C++11
271  */
272  template<typename _Tp>
273  struct is_placeholder
274  : public integral_constant<int, 0>
275  { };
276 
277 #if __cplusplus > 201402L
278  template <typename _Tp> inline constexpr bool is_bind_expression_v
279  = is_bind_expression<_Tp>::value;
280  template <typename _Tp> inline constexpr int is_placeholder_v
281  = is_placeholder<_Tp>::value;
282 #endif // C++17
283 
284  /** @namespace std::placeholders
285  * @brief ISO C++ 2011 namespace for std::bind placeholders.
286  * @ingroup binders
287  * @since C++11
288  */
289  namespace placeholders
290  {
291  /* Define a large number of placeholders. There is no way to
292  * simplify this with variadic templates, because we're introducing
293  * unique names for each.
294  */
295 #if __cpp_inline_variables
296 # define _GLIBCXX_PLACEHOLDER inline
297 #else
298 # define _GLIBCXX_PLACEHOLDER extern
299 #endif
300 
301  _GLIBCXX_PLACEHOLDER const _Placeholder<1> _1;
302  _GLIBCXX_PLACEHOLDER const _Placeholder<2> _2;
303  _GLIBCXX_PLACEHOLDER const _Placeholder<3> _3;
304  _GLIBCXX_PLACEHOLDER const _Placeholder<4> _4;
305  _GLIBCXX_PLACEHOLDER const _Placeholder<5> _5;
306  _GLIBCXX_PLACEHOLDER const _Placeholder<6> _6;
307  _GLIBCXX_PLACEHOLDER const _Placeholder<7> _7;
308  _GLIBCXX_PLACEHOLDER const _Placeholder<8> _8;
309  _GLIBCXX_PLACEHOLDER const _Placeholder<9> _9;
310  _GLIBCXX_PLACEHOLDER const _Placeholder<10> _10;
311  _GLIBCXX_PLACEHOLDER const _Placeholder<11> _11;
312  _GLIBCXX_PLACEHOLDER const _Placeholder<12> _12;
313  _GLIBCXX_PLACEHOLDER const _Placeholder<13> _13;
314  _GLIBCXX_PLACEHOLDER const _Placeholder<14> _14;
315  _GLIBCXX_PLACEHOLDER const _Placeholder<15> _15;
316  _GLIBCXX_PLACEHOLDER const _Placeholder<16> _16;
317  _GLIBCXX_PLACEHOLDER const _Placeholder<17> _17;
318  _GLIBCXX_PLACEHOLDER const _Placeholder<18> _18;
319  _GLIBCXX_PLACEHOLDER const _Placeholder<19> _19;
320  _GLIBCXX_PLACEHOLDER const _Placeholder<20> _20;
321  _GLIBCXX_PLACEHOLDER const _Placeholder<21> _21;
322  _GLIBCXX_PLACEHOLDER const _Placeholder<22> _22;
323  _GLIBCXX_PLACEHOLDER const _Placeholder<23> _23;
324  _GLIBCXX_PLACEHOLDER const _Placeholder<24> _24;
325  _GLIBCXX_PLACEHOLDER const _Placeholder<25> _25;
326  _GLIBCXX_PLACEHOLDER const _Placeholder<26> _26;
327  _GLIBCXX_PLACEHOLDER const _Placeholder<27> _27;
328  _GLIBCXX_PLACEHOLDER const _Placeholder<28> _28;
329  _GLIBCXX_PLACEHOLDER const _Placeholder<29> _29;
330 
331 #undef _GLIBCXX_PLACEHOLDER
332  }
333 
334  /**
335  * Partial specialization of is_placeholder that provides the placeholder
336  * number for the placeholder objects defined by libstdc++.
337  * @ingroup binders
338  * @since C++11
339  */
340  template<int _Num>
341  struct is_placeholder<_Placeholder<_Num> >
342  : public integral_constant<int, _Num>
343  { };
344 
345  template<int _Num>
346  struct is_placeholder<const _Placeholder<_Num> >
347  : public integral_constant<int, _Num>
348  { };
349 
350  /// @cond undocumented
351 
352  // Like tuple_element_t but SFINAE-friendly.
353  template<std::size_t __i, typename _Tuple>
354  using _Safe_tuple_element_t
355  = typename enable_if<(__i < tuple_size<_Tuple>::value),
356  tuple_element<__i, _Tuple>>::type::type;
357 
358  /**
359  * Maps an argument to bind() into an actual argument to the bound
360  * function object [func.bind.bind]/10. Only the first parameter should
361  * be specified: the rest are used to determine among the various
362  * implementations. Note that, although this class is a function
363  * object, it isn't entirely normal because it takes only two
364  * parameters regardless of the number of parameters passed to the
365  * bind expression. The first parameter is the bound argument and
366  * the second parameter is a tuple containing references to the
367  * rest of the arguments.
368  */
369  template<typename _Arg,
370  bool _IsBindExp = is_bind_expression<_Arg>::value,
371  bool _IsPlaceholder = (is_placeholder<_Arg>::value > 0)>
372  class _Mu;
373 
374  /**
375  * If the argument is reference_wrapper<_Tp>, returns the
376  * underlying reference.
377  * C++11 [func.bind.bind] p10 bullet 1.
378  */
379  template<typename _Tp>
380  class _Mu<reference_wrapper<_Tp>, false, false>
381  {
382  public:
383  /* Note: This won't actually work for const volatile
384  * reference_wrappers, because reference_wrapper::get() is const
385  * but not volatile-qualified. This might be a defect in the TR.
386  */
387  template<typename _CVRef, typename _Tuple>
388  _GLIBCXX20_CONSTEXPR
389  _Tp&
390  operator()(_CVRef& __arg, _Tuple&) const volatile
391  { return __arg.get(); }
392  };
393 
394  /**
395  * If the argument is a bind expression, we invoke the underlying
396  * function object with the same cv-qualifiers as we are given and
397  * pass along all of our arguments (unwrapped).
398  * C++11 [func.bind.bind] p10 bullet 2.
399  */
400  template<typename _Arg>
401  class _Mu<_Arg, true, false>
402  {
403  public:
404  template<typename _CVArg, typename... _Args>
405  _GLIBCXX20_CONSTEXPR
406  auto
407  operator()(_CVArg& __arg,
408  tuple<_Args...>& __tuple) const volatile
409  -> decltype(__arg(declval<_Args>()...))
410  {
411  // Construct an index tuple and forward to __call
412  typedef typename _Build_index_tuple<sizeof...(_Args)>::__type
413  _Indexes;
414  return this->__call(__arg, __tuple, _Indexes());
415  }
416 
417  private:
418  // Invokes the underlying function object __arg by unpacking all
419  // of the arguments in the tuple.
420  template<typename _CVArg, typename... _Args, std::size_t... _Indexes>
421  _GLIBCXX20_CONSTEXPR
422  auto
423  __call(_CVArg& __arg, tuple<_Args...>& __tuple,
424  const _Index_tuple<_Indexes...>&) const volatile
425  -> decltype(__arg(declval<_Args>()...))
426  {
427  return __arg(std::get<_Indexes>(std::move(__tuple))...);
428  }
429  };
430 
431  /**
432  * If the argument is a placeholder for the Nth argument, returns
433  * a reference to the Nth argument to the bind function object.
434  * C++11 [func.bind.bind] p10 bullet 3.
435  */
436  template<typename _Arg>
437  class _Mu<_Arg, false, true>
438  {
439  public:
440  template<typename _Tuple>
441  _GLIBCXX20_CONSTEXPR
442  _Safe_tuple_element_t<(is_placeholder<_Arg>::value - 1), _Tuple>&&
443  operator()(const volatile _Arg&, _Tuple& __tuple) const volatile
444  {
445  return
446  ::std::get<(is_placeholder<_Arg>::value - 1)>(std::move(__tuple));
447  }
448  };
449 
450  /**
451  * If the argument is just a value, returns a reference to that
452  * value. The cv-qualifiers on the reference are determined by the caller.
453  * C++11 [func.bind.bind] p10 bullet 4.
454  */
455  template<typename _Arg>
456  class _Mu<_Arg, false, false>
457  {
458  public:
459  template<typename _CVArg, typename _Tuple>
460  _GLIBCXX20_CONSTEXPR
461  _CVArg&&
462  operator()(_CVArg&& __arg, _Tuple&) const volatile
463  { return std::forward<_CVArg>(__arg); }
464  };
465 
466  // std::get<I> for volatile-qualified tuples
467  template<std::size_t _Ind, typename... _Tp>
468  inline auto
469  __volget(volatile tuple<_Tp...>& __tuple)
470  -> __tuple_element_t<_Ind, tuple<_Tp...>> volatile&
471  { return std::get<_Ind>(const_cast<tuple<_Tp...>&>(__tuple)); }
472 
473  // std::get<I> for const-volatile-qualified tuples
474  template<std::size_t _Ind, typename... _Tp>
475  inline auto
476  __volget(const volatile tuple<_Tp...>& __tuple)
477  -> __tuple_element_t<_Ind, tuple<_Tp...>> const volatile&
478  { return std::get<_Ind>(const_cast<const tuple<_Tp...>&>(__tuple)); }
479 
480  /// @endcond
481 
482 #if __cplusplus == 201703L && _GLIBCXX_USE_DEPRECATED
483 # define _GLIBCXX_VOLATILE_BIND
484 // _GLIBCXX_RESOLVE_LIB_DEFECTS
485 // 2487. bind() should be const-overloaded, not cv-overloaded
486 # define _GLIBCXX_DEPR_BIND \
487  [[deprecated("std::bind does not support volatile in C++17")]]
488 #elif __cplusplus < 201703L
489 # define _GLIBCXX_VOLATILE_BIND
490 # define _GLIBCXX_DEPR_BIND
491 #endif
492 
493  /// Type of the function object returned from bind().
494  template<typename _Signature>
495  class _Bind;
496 
497  template<typename _Functor, typename... _Bound_args>
498  class _Bind<_Functor(_Bound_args...)>
499  : public _Weak_result_type<_Functor>
500  {
501  typedef typename _Build_index_tuple<sizeof...(_Bound_args)>::__type
502  _Bound_indexes;
503 
504  _Functor _M_f;
505  tuple<_Bound_args...> _M_bound_args;
506 
507  // Call unqualified
508  template<typename _Result, typename... _Args, std::size_t... _Indexes>
509  _GLIBCXX20_CONSTEXPR
510  _Result
511  __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>)
512  {
513  return std::__invoke(_M_f,
514  _Mu<_Bound_args>()(std::get<_Indexes>(_M_bound_args), __args)...
515  );
516  }
517 
518  // Call as const
519  template<typename _Result, typename... _Args, std::size_t... _Indexes>
520  _GLIBCXX20_CONSTEXPR
521  _Result
522  __call_c(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>) const
523  {
524  return std::__invoke(_M_f,
525  _Mu<_Bound_args>()(std::get<_Indexes>(_M_bound_args), __args)...
526  );
527  }
528 
529 #ifdef _GLIBCXX_VOLATILE_BIND
530  // Call as volatile
531  template<typename _Result, typename... _Args, std::size_t... _Indexes>
532  _Result
533  __call_v(tuple<_Args...>&& __args,
534  _Index_tuple<_Indexes...>) volatile
535  {
536  return std::__invoke(_M_f,
537  _Mu<_Bound_args>()(__volget<_Indexes>(_M_bound_args), __args)...
538  );
539  }
540 
541  // Call as const volatile
542  template<typename _Result, typename... _Args, std::size_t... _Indexes>
543  _Result
544  __call_c_v(tuple<_Args...>&& __args,
545  _Index_tuple<_Indexes...>) const volatile
546  {
547  return std::__invoke(_M_f,
548  _Mu<_Bound_args>()(__volget<_Indexes>(_M_bound_args), __args)...
549  );
550  }
551 #endif // volatile
552 
553  template<typename _BoundArg, typename _CallArgs>
554  using _Mu_type = decltype(
555  _Mu<typename remove_cv<_BoundArg>::type>()(
556  std::declval<_BoundArg&>(), std::declval<_CallArgs&>()) );
557 
558  template<typename _Fn, typename _CallArgs, typename... _BArgs>
559  using _Res_type_impl
560  = __invoke_result_t<_Fn&, _Mu_type<_BArgs, _CallArgs>&&...>;
561 
562  template<typename _CallArgs>
563  using _Res_type = _Res_type_impl<_Functor, _CallArgs, _Bound_args...>;
564 
565  template<typename _CallArgs>
566  using __dependent = typename
567  enable_if<bool(tuple_size<_CallArgs>::value+1), _Functor>::type;
568 
569  template<typename _CallArgs, template<class> class __cv_quals>
570  using _Res_type_cv = _Res_type_impl<
571  typename __cv_quals<__dependent<_CallArgs>>::type,
572  _CallArgs,
573  typename __cv_quals<_Bound_args>::type...>;
574 
575  public:
576  template<typename... _Args>
577  explicit _GLIBCXX20_CONSTEXPR
578  _Bind(const _Functor& __f, _Args&&... __args)
579  : _M_f(__f), _M_bound_args(std::forward<_Args>(__args)...)
580  { }
581 
582  template<typename... _Args>
583  explicit _GLIBCXX20_CONSTEXPR
584  _Bind(_Functor&& __f, _Args&&... __args)
585  : _M_f(std::move(__f)), _M_bound_args(std::forward<_Args>(__args)...)
586  { }
587 
588  _Bind(const _Bind&) = default;
589  _Bind(_Bind&&) = default;
590 
591  // Call unqualified
592  template<typename... _Args,
593  typename _Result = _Res_type<tuple<_Args...>>>
594  _GLIBCXX20_CONSTEXPR
595  _Result
596  operator()(_Args&&... __args)
597  {
598  return this->__call<_Result>(
599  std::forward_as_tuple(std::forward<_Args>(__args)...),
600  _Bound_indexes());
601  }
602 
603  // Call as const
604  template<typename... _Args,
605  typename _Result = _Res_type_cv<tuple<_Args...>, add_const>>
606  _GLIBCXX20_CONSTEXPR
607  _Result
608  operator()(_Args&&... __args) const
609  {
610  return this->__call_c<_Result>(
611  std::forward_as_tuple(std::forward<_Args>(__args)...),
612  _Bound_indexes());
613  }
614 
615 #ifdef _GLIBCXX_VOLATILE_BIND
616  // Call as volatile
617  template<typename... _Args,
618  typename _Result = _Res_type_cv<tuple<_Args...>, add_volatile>>
619  _GLIBCXX_DEPR_BIND
620  _Result
621  operator()(_Args&&... __args) volatile
622  {
623  return this->__call_v<_Result>(
624  std::forward_as_tuple(std::forward<_Args>(__args)...),
625  _Bound_indexes());
626  }
627 
628  // Call as const volatile
629  template<typename... _Args,
630  typename _Result = _Res_type_cv<tuple<_Args...>, add_cv>>
631  _GLIBCXX_DEPR_BIND
632  _Result
633  operator()(_Args&&... __args) const volatile
634  {
635  return this->__call_c_v<_Result>(
636  std::forward_as_tuple(std::forward<_Args>(__args)...),
637  _Bound_indexes());
638  }
639 #endif // volatile
640  };
641 
642  /// Type of the function object returned from bind<R>().
643  template<typename _Result, typename _Signature>
644  class _Bind_result;
645 
646  template<typename _Result, typename _Functor, typename... _Bound_args>
647  class _Bind_result<_Result, _Functor(_Bound_args...)>
648  {
649  typedef typename _Build_index_tuple<sizeof...(_Bound_args)>::__type
650  _Bound_indexes;
651 
652  _Functor _M_f;
653  tuple<_Bound_args...> _M_bound_args;
654 
655  // Call unqualified
656  template<typename _Res, typename... _Args, std::size_t... _Indexes>
657  _GLIBCXX20_CONSTEXPR
658  _Res
659  __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>)
660  {
661  return std::__invoke_r<_Res>(_M_f, _Mu<_Bound_args>()
662  (std::get<_Indexes>(_M_bound_args), __args)...);
663  }
664 
665  // Call as const
666  template<typename _Res, typename... _Args, std::size_t... _Indexes>
667  _GLIBCXX20_CONSTEXPR
668  _Res
669  __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>) const
670  {
671  return std::__invoke_r<_Res>(_M_f, _Mu<_Bound_args>()
672  (std::get<_Indexes>(_M_bound_args), __args)...);
673  }
674 
675 #ifdef _GLIBCXX_VOLATILE_BIND
676  // Call as volatile
677  template<typename _Res, typename... _Args, std::size_t... _Indexes>
678  _Res
679  __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>) volatile
680  {
681  return std::__invoke_r<_Res>(_M_f, _Mu<_Bound_args>()
682  (__volget<_Indexes>(_M_bound_args), __args)...);
683  }
684 
685  // Call as const volatile
686  template<typename _Res, typename... _Args, std::size_t... _Indexes>
687  _Res
688  __call(tuple<_Args...>&& __args,
689  _Index_tuple<_Indexes...>) const volatile
690  {
691  return std::__invoke_r<_Res>(_M_f, _Mu<_Bound_args>()
692  (__volget<_Indexes>(_M_bound_args), __args)...);
693  }
694 #endif // volatile
695 
696  public:
697  typedef _Result result_type;
698 
699  template<typename... _Args>
700  explicit _GLIBCXX20_CONSTEXPR
701  _Bind_result(const _Functor& __f, _Args&&... __args)
702  : _M_f(__f), _M_bound_args(std::forward<_Args>(__args)...)
703  { }
704 
705  template<typename... _Args>
706  explicit _GLIBCXX20_CONSTEXPR
707  _Bind_result(_Functor&& __f, _Args&&... __args)
708  : _M_f(std::move(__f)), _M_bound_args(std::forward<_Args>(__args)...)
709  { }
710 
711  _Bind_result(const _Bind_result&) = default;
712  _Bind_result(_Bind_result&&) = default;
713 
714  // Call unqualified
715  template<typename... _Args>
716  _GLIBCXX20_CONSTEXPR
717  result_type
718  operator()(_Args&&... __args)
719  {
720  return this->__call<_Result>(
721  std::forward_as_tuple(std::forward<_Args>(__args)...),
722  _Bound_indexes());
723  }
724 
725  // Call as const
726  template<typename... _Args>
727  _GLIBCXX20_CONSTEXPR
728  result_type
729  operator()(_Args&&... __args) const
730  {
731  return this->__call<_Result>(
732  std::forward_as_tuple(std::forward<_Args>(__args)...),
733  _Bound_indexes());
734  }
735 
736 #ifdef _GLIBCXX_VOLATILE_BIND
737  // Call as volatile
738  template<typename... _Args>
739  _GLIBCXX_DEPR_BIND
740  result_type
741  operator()(_Args&&... __args) volatile
742  {
743  return this->__call<_Result>(
744  std::forward_as_tuple(std::forward<_Args>(__args)...),
745  _Bound_indexes());
746  }
747 
748  // Call as const volatile
749  template<typename... _Args>
750  _GLIBCXX_DEPR_BIND
751  result_type
752  operator()(_Args&&... __args) const volatile
753  {
754  return this->__call<_Result>(
755  std::forward_as_tuple(std::forward<_Args>(__args)...),
756  _Bound_indexes());
757  }
758 #else
759  template<typename... _Args>
760  void operator()(_Args&&...) const volatile = delete;
761 #endif // volatile
762  };
763 
764 #undef _GLIBCXX_VOLATILE_BIND
765 #undef _GLIBCXX_DEPR_BIND
766 
767  /**
768  * @brief Class template _Bind is always a bind expression.
769  * @ingroup binders
770  */
771  template<typename _Signature>
772  struct is_bind_expression<_Bind<_Signature> >
773  : public true_type { };
774 
775  /**
776  * @brief Class template _Bind is always a bind expression.
777  * @ingroup binders
778  */
779  template<typename _Signature>
780  struct is_bind_expression<const _Bind<_Signature> >
781  : public true_type { };
782 
783  /**
784  * @brief Class template _Bind is always a bind expression.
785  * @ingroup binders
786  */
787  template<typename _Signature>
788  struct is_bind_expression<volatile _Bind<_Signature> >
789  : public true_type { };
790 
791  /**
792  * @brief Class template _Bind is always a bind expression.
793  * @ingroup binders
794  */
795  template<typename _Signature>
796  struct is_bind_expression<const volatile _Bind<_Signature>>
797  : public true_type { };
798 
799  /**
800  * @brief Class template _Bind_result is always a bind expression.
801  * @ingroup binders
802  */
803  template<typename _Result, typename _Signature>
804  struct is_bind_expression<_Bind_result<_Result, _Signature>>
805  : public true_type { };
806 
807  /**
808  * @brief Class template _Bind_result is always a bind expression.
809  * @ingroup binders
810  */
811  template<typename _Result, typename _Signature>
812  struct is_bind_expression<const _Bind_result<_Result, _Signature>>
813  : public true_type { };
814 
815  /**
816  * @brief Class template _Bind_result is always a bind expression.
817  * @ingroup binders
818  */
819  template<typename _Result, typename _Signature>
820  struct is_bind_expression<volatile _Bind_result<_Result, _Signature>>
821  : public true_type { };
822 
823  /**
824  * @brief Class template _Bind_result is always a bind expression.
825  * @ingroup binders
826  */
827  template<typename _Result, typename _Signature>
828  struct is_bind_expression<const volatile _Bind_result<_Result, _Signature>>
829  : public true_type { };
830 
831  template<typename _Func, typename... _BoundArgs>
832  struct _Bind_check_arity { };
833 
834  template<typename _Ret, typename... _Args, typename... _BoundArgs>
835  struct _Bind_check_arity<_Ret (*)(_Args...), _BoundArgs...>
836  {
837  static_assert(sizeof...(_BoundArgs) == sizeof...(_Args),
838  "Wrong number of arguments for function");
839  };
840 
841  template<typename _Ret, typename... _Args, typename... _BoundArgs>
842  struct _Bind_check_arity<_Ret (*)(_Args......), _BoundArgs...>
843  {
844  static_assert(sizeof...(_BoundArgs) >= sizeof...(_Args),
845  "Wrong number of arguments for function");
846  };
847 
848  template<typename _Tp, typename _Class, typename... _BoundArgs>
849  struct _Bind_check_arity<_Tp _Class::*, _BoundArgs...>
850  {
851  using _Arity = typename _Mem_fn<_Tp _Class::*>::_Arity;
852  using _Varargs = typename _Mem_fn<_Tp _Class::*>::_Varargs;
853  static_assert(_Varargs::value
854  ? sizeof...(_BoundArgs) >= _Arity::value + 1
855  : sizeof...(_BoundArgs) == _Arity::value + 1,
856  "Wrong number of arguments for pointer-to-member");
857  };
858 
859  // Trait type used to remove std::bind() from overload set via SFINAE
860  // when first argument has integer type, so that std::bind() will
861  // not be a better match than ::bind() from the BSD Sockets API.
862  template<typename _Tp, typename _Tp2 = typename decay<_Tp>::type>
863  using __is_socketlike = __or_<is_integral<_Tp2>, is_enum<_Tp2>>;
864 
865  template<bool _SocketLike, typename _Func, typename... _BoundArgs>
866  struct _Bind_helper
867  : _Bind_check_arity<typename decay<_Func>::type, _BoundArgs...>
868  {
869  typedef typename decay<_Func>::type __func_type;
870  typedef _Bind<__func_type(typename decay<_BoundArgs>::type...)> type;
871  };
872 
873  // Partial specialization for is_socketlike == true, does not define
874  // nested type so std::bind() will not participate in overload resolution
875  // when the first argument might be a socket file descriptor.
876  template<typename _Func, typename... _BoundArgs>
877  struct _Bind_helper<true, _Func, _BoundArgs...>
878  { };
879 
880  /**
881  * @brief Function template for std::bind.
882  * @ingroup binders
883  * @since C++11
884  */
885  template<typename _Func, typename... _BoundArgs>
886  inline _GLIBCXX20_CONSTEXPR typename
887  _Bind_helper<__is_socketlike<_Func>::value, _Func, _BoundArgs...>::type
888  bind(_Func&& __f, _BoundArgs&&... __args)
889  {
890  typedef _Bind_helper<false, _Func, _BoundArgs...> __helper_type;
891  return typename __helper_type::type(std::forward<_Func>(__f),
892  std::forward<_BoundArgs>(__args)...);
893  }
894 
895  template<typename _Result, typename _Func, typename... _BoundArgs>
896  struct _Bindres_helper
897  : _Bind_check_arity<typename decay<_Func>::type, _BoundArgs...>
898  {
899  typedef typename decay<_Func>::type __functor_type;
900  typedef _Bind_result<_Result,
901  __functor_type(typename decay<_BoundArgs>::type...)>
902  type;
903  };
904 
905  /**
906  * @brief Function template for std::bind<R>.
907  * @ingroup binders
908  * @since C++11
909  */
910  template<typename _Result, typename _Func, typename... _BoundArgs>
911  inline _GLIBCXX20_CONSTEXPR
912  typename _Bindres_helper<_Result, _Func, _BoundArgs...>::type
913  bind(_Func&& __f, _BoundArgs&&... __args)
914  {
915  typedef _Bindres_helper<_Result, _Func, _BoundArgs...> __helper_type;
916  return typename __helper_type::type(std::forward<_Func>(__f),
917  std::forward<_BoundArgs>(__args)...);
918  }
919 
920 #ifdef __cpp_lib_bind_front // C++ >= 20
921 
922  template<typename _Fd, typename... _BoundArgs>
923  struct _Bind_front
924  {
925  static_assert(is_move_constructible_v<_Fd>);
926  static_assert((is_move_constructible_v<_BoundArgs> && ...));
927 
928  // First parameter is to ensure this constructor is never used
929  // instead of the copy/move constructor.
930  template<typename _Fn, typename... _Args>
931  explicit constexpr
932  _Bind_front(int, _Fn&& __fn, _Args&&... __args)
933  noexcept(__and_<is_nothrow_constructible<_Fd, _Fn>,
934  is_nothrow_constructible<_BoundArgs, _Args>...>::value)
935  : _M_fd(std::forward<_Fn>(__fn)),
936  _M_bound_args(std::forward<_Args>(__args)...)
937  { static_assert(sizeof...(_Args) == sizeof...(_BoundArgs)); }
938 
939 #if __cpp_explicit_this_parameter
940  template<typename _Self, typename... _CallArgs>
941  constexpr
942  invoke_result_t<__like_t<_Self, _Fd>, __like_t<_Self, _BoundArgs>..., _CallArgs...>
943  operator()(this _Self&& __self, _CallArgs&&... __call_args)
944  noexcept(is_nothrow_invocable_v<__like_t<_Self, _Fd>,
945  __like_t<_Self, _BoundArgs>..., _CallArgs...>)
946  {
947  return _S_call(std::forward<_Self>(__self), _BoundIndices(),
948  std::forward<_CallArgs>(__call_args)...);
949  }
950 #else
951  template<typename... _CallArgs>
952  requires true
953  constexpr
954  invoke_result_t<_Fd&, _BoundArgs&..., _CallArgs...>
955  operator()(_CallArgs&&... __call_args) &
956  noexcept(is_nothrow_invocable_v<_Fd&, _BoundArgs&..., _CallArgs...>)
957  {
958  return _S_call(*this, _BoundIndices(),
959  std::forward<_CallArgs>(__call_args)...);
960  }
961 
962  template<typename... _CallArgs>
963  requires true
964  constexpr
965  invoke_result_t<const _Fd&, const _BoundArgs&..., _CallArgs...>
966  operator()(_CallArgs&&... __call_args) const &
967  noexcept(is_nothrow_invocable_v<const _Fd&, const _BoundArgs&...,
968  _CallArgs...>)
969  {
970  return _S_call(*this, _BoundIndices(),
971  std::forward<_CallArgs>(__call_args)...);
972  }
973 
974  template<typename... _CallArgs>
975  requires true
976  constexpr
977  invoke_result_t<_Fd, _BoundArgs..., _CallArgs...>
978  operator()(_CallArgs&&... __call_args) &&
979  noexcept(is_nothrow_invocable_v<_Fd, _BoundArgs..., _CallArgs...>)
980  {
981  return _S_call(std::move(*this), _BoundIndices(),
982  std::forward<_CallArgs>(__call_args)...);
983  }
984 
985  template<typename... _CallArgs>
986  requires true
987  constexpr
988  invoke_result_t<const _Fd, const _BoundArgs..., _CallArgs...>
989  operator()(_CallArgs&&... __call_args) const &&
990  noexcept(is_nothrow_invocable_v<const _Fd, const _BoundArgs...,
991  _CallArgs...>)
992  {
993  return _S_call(std::move(*this), _BoundIndices(),
994  std::forward<_CallArgs>(__call_args)...);
995  }
996 
997  template<typename... _CallArgs>
998  void operator()(_CallArgs&&...) & = delete;
999 
1000  template<typename... _CallArgs>
1001  void operator()(_CallArgs&&...) const & = delete;
1002 
1003  template<typename... _CallArgs>
1004  void operator()(_CallArgs&&...) && = delete;
1005 
1006  template<typename... _CallArgs>
1007  void operator()(_CallArgs&&...) const && = delete;
1008 #endif
1009 
1010  private:
1011  using _BoundIndices = index_sequence_for<_BoundArgs...>;
1012 
1013  template<typename _Tp, size_t... _Ind, typename... _CallArgs>
1014  static constexpr
1015  decltype(auto)
1016  _S_call(_Tp&& __g, index_sequence<_Ind...>, _CallArgs&&... __call_args)
1017  {
1018  return std::invoke(std::forward<_Tp>(__g)._M_fd,
1019  std::get<_Ind>(std::forward<_Tp>(__g)._M_bound_args)...,
1020  std::forward<_CallArgs>(__call_args)...);
1021  }
1022 
1023  [[no_unique_address]] _Fd _M_fd;
1024  [[no_unique_address]] std::tuple<_BoundArgs...> _M_bound_args;
1025  };
1026 
1027  template<typename _Fn, typename... _Args>
1028  using _Bind_front_t = _Bind_front<decay_t<_Fn>, decay_t<_Args>...>;
1029 
1030  /** Create call wrapper by partial application of arguments to function.
1031  *
1032  * The result of `std::bind_front(f, args...)` is a function object that
1033  * stores `f` and the bound arguments, `args...`. When that function
1034  * object is invoked with `call_args...` it returns the result of calling
1035  * `f(args..., call_args...)`.
1036  *
1037  * @since C++20
1038  */
1039  template<typename _Fn, typename... _Args>
1040  constexpr _Bind_front_t<_Fn, _Args...>
1041  bind_front(_Fn&& __fn, _Args&&... __args)
1042  noexcept(is_nothrow_constructible_v<_Bind_front_t<_Fn, _Args...>,
1043  int, _Fn, _Args...>)
1044  {
1045  return _Bind_front_t<_Fn, _Args...>(0, std::forward<_Fn>(__fn),
1046  std::forward<_Args>(__args)...);
1047  }
1048 #endif // __cpp_lib_bind_front
1049 
1050 #ifdef __cpp_lib_bind_back // C++ >= 23
1051  template<typename _Fd, typename... _BoundArgs>
1052  struct _Bind_back
1053  {
1054  static_assert(is_move_constructible_v<_Fd>);
1055  static_assert((is_move_constructible_v<_BoundArgs> && ...));
1056 
1057  // First parameter is to ensure this constructor is never used
1058  // instead of the copy/move constructor.
1059  template<typename _Fn, typename... _Args>
1060  explicit constexpr
1061  _Bind_back(int, _Fn&& __fn, _Args&&... __args)
1062  noexcept(__and_<is_nothrow_constructible<_Fd, _Fn>,
1063  is_nothrow_constructible<_BoundArgs, _Args>...>::value)
1064  : _M_fd(std::forward<_Fn>(__fn)),
1065  _M_bound_args(std::forward<_Args>(__args)...)
1066  { static_assert(sizeof...(_Args) == sizeof...(_BoundArgs)); }
1067 
1068  template<typename _Self, typename... _CallArgs>
1069  constexpr
1070  invoke_result_t<__like_t<_Self, _Fd>, _CallArgs..., __like_t<_Self, _BoundArgs>...>
1071  operator()(this _Self&& __self, _CallArgs&&... __call_args)
1072  noexcept(is_nothrow_invocable_v<__like_t<_Self, _Fd>,
1073  _CallArgs..., __like_t<_Self, _BoundArgs>...>)
1074  {
1075  return _S_call(std::forward<_Self>(__self), _BoundIndices(),
1076  std::forward<_CallArgs>(__call_args)...);
1077  }
1078 
1079  private:
1080  using _BoundIndices = index_sequence_for<_BoundArgs...>;
1081 
1082  template<typename _Tp, size_t... _Ind, typename... _CallArgs>
1083  static constexpr
1084  decltype(auto)
1085  _S_call(_Tp&& __g, index_sequence<_Ind...>, _CallArgs&&... __call_args)
1086  {
1087  return std::invoke(std::forward<_Tp>(__g)._M_fd,
1088  std::forward<_CallArgs>(__call_args)...,
1089  std::get<_Ind>(std::forward<_Tp>(__g)._M_bound_args)...);
1090  }
1091 
1092  [[no_unique_address]] _Fd _M_fd;
1093  [[no_unique_address]] std::tuple<_BoundArgs...> _M_bound_args;
1094  };
1095 
1096  template<typename _Fn, typename... _Args>
1097  using _Bind_back_t = _Bind_back<decay_t<_Fn>, decay_t<_Args>...>;
1098 
1099  /** Create call wrapper by partial application of arguments to function.
1100  *
1101  * The result of `std::bind_back(f, args...)` is a function object that
1102  * stores `f` and the bound arguments, `args...`. When that function
1103  * object is invoked with `call_args...` it returns the result of calling
1104  * `f(call_args..., args...)`.
1105  *
1106  * @since C++23
1107  */
1108  template<typename _Fn, typename... _Args>
1109  constexpr _Bind_back_t<_Fn, _Args...>
1110  bind_back(_Fn&& __fn, _Args&&... __args)
1111  noexcept(is_nothrow_constructible_v<_Bind_back_t<_Fn, _Args...>,
1112  int, _Fn, _Args...>)
1113  {
1114  return _Bind_back_t<_Fn, _Args...>(0, std::forward<_Fn>(__fn),
1115  std::forward<_Args>(__args)...);
1116  }
1117 #endif // __cpp_lib_bind_back
1118 
1119 #if __cplusplus >= 201402L
1120  /// Generalized negator.
1121  template<typename _Fn>
1122  class _Not_fn
1123  {
1124  template<typename _Fn2, typename... _Args>
1125  using __inv_res_t = typename __invoke_result<_Fn2, _Args...>::type;
1126 
1127  template<typename _Tp>
1128  static decltype(!std::declval<_Tp>())
1129  _S_not() noexcept(noexcept(!std::declval<_Tp>()));
1130 
1131  public:
1132  template<typename _Fn2>
1133  constexpr
1134  _Not_fn(_Fn2&& __fn, int)
1135  : _M_fn(std::forward<_Fn2>(__fn)) { }
1136 
1137  _Not_fn(const _Not_fn& __fn) = default;
1138  _Not_fn(_Not_fn&& __fn) = default;
1139  ~_Not_fn() = default;
1140 
1141  // Macro to define operator() with given cv-qualifiers ref-qualifiers,
1142  // forwarding _M_fn and the function arguments with the same qualifiers,
1143  // and deducing the return type and exception-specification.
1144 #define _GLIBCXX_NOT_FN_CALL_OP( _QUALS ) \
1145  template<typename... _Args, \
1146  typename = enable_if_t<__is_invocable<_Fn _QUALS, _Args...>::value>> \
1147  _GLIBCXX20_CONSTEXPR \
1148  decltype(_S_not<__inv_res_t<_Fn _QUALS, _Args...>>()) \
1149  operator()(_Args&&... __args) _QUALS \
1150  noexcept(__is_nothrow_invocable<_Fn _QUALS, _Args...>::value \
1151  && noexcept(_S_not<__inv_res_t<_Fn _QUALS, _Args...>>())) \
1152  { \
1153  return !std::__invoke(std::forward< _Fn _QUALS >(_M_fn), \
1154  std::forward<_Args>(__args)...); \
1155  } \
1156  \
1157  template<typename... _Args, \
1158  typename = enable_if_t<!__is_invocable<_Fn _QUALS, _Args...>::value>> \
1159  void operator()(_Args&&... __args) _QUALS = delete;
1160 
1161  _GLIBCXX_NOT_FN_CALL_OP( & )
1162  _GLIBCXX_NOT_FN_CALL_OP( const & )
1163  _GLIBCXX_NOT_FN_CALL_OP( && )
1164  _GLIBCXX_NOT_FN_CALL_OP( const && )
1165 #undef _GLIBCXX_NOT_FN_CALL_OP
1166 
1167  private:
1168  _Fn _M_fn;
1169  };
1170 
1171  template<typename _Tp, typename _Pred>
1172  struct __is_byte_like : false_type { };
1173 
1174  template<typename _Tp>
1175  struct __is_byte_like<_Tp, equal_to<_Tp>>
1176  : __bool_constant<sizeof(_Tp) == 1 && is_integral<_Tp>::value> { };
1177 
1178  template<typename _Tp>
1179  struct __is_byte_like<_Tp, equal_to<void>>
1180  : __bool_constant<sizeof(_Tp) == 1 && is_integral<_Tp>::value> { };
1181 
1182 #if __cplusplus >= 201703L
1183  // Declare std::byte (full definition is in <cstddef>).
1184  enum class byte : unsigned char;
1185 
1186  template<>
1187  struct __is_byte_like<byte, equal_to<byte>>
1188  : true_type { };
1189 
1190  template<>
1191  struct __is_byte_like<byte, equal_to<void>>
1192  : true_type { };
1193 #endif
1194 
1195  // [func.not_fn] Function template not_fn
1196 #ifdef __cpp_lib_not_fn // C++ >= 17
1197  /** Wrap a function object to create one that negates its result.
1198  *
1199  * The function template `std::not_fn` creates a "forwarding call wrapper",
1200  * which is a function object that wraps another function object and
1201  * when called, forwards its arguments to the wrapped function object.
1202  *
1203  * The result of invoking the wrapper is the negation (using `!`) of
1204  * the wrapped function object.
1205  *
1206  * @ingroup functors
1207  * @since C++17
1208  */
1209  template<typename _Fn>
1210  _GLIBCXX20_CONSTEXPR
1211  inline auto
1212  not_fn(_Fn&& __fn)
1213  noexcept(std::is_nothrow_constructible<std::decay_t<_Fn>, _Fn&&>::value)
1214  {
1215  return _Not_fn<std::decay_t<_Fn>>{std::forward<_Fn>(__fn), 0};
1216  }
1217 #endif
1218 
1219 #if __cplusplus >= 201703L
1220  // Searchers
1221 
1222  template<typename _ForwardIterator1, typename _BinaryPredicate = equal_to<>>
1223  class default_searcher
1224  {
1225  public:
1226  _GLIBCXX20_CONSTEXPR
1227  default_searcher(_ForwardIterator1 __pat_first,
1228  _ForwardIterator1 __pat_last,
1229  _BinaryPredicate __pred = _BinaryPredicate())
1230  : _M_m(__pat_first, __pat_last, std::move(__pred))
1231  { }
1232 
1233  template<typename _ForwardIterator2>
1234  _GLIBCXX20_CONSTEXPR
1235  pair<_ForwardIterator2, _ForwardIterator2>
1236  operator()(_ForwardIterator2 __first, _ForwardIterator2 __last) const
1237  {
1238  _ForwardIterator2 __first_ret =
1239  std::search(__first, __last, std::get<0>(_M_m), std::get<1>(_M_m),
1240  std::get<2>(_M_m));
1241  auto __ret = std::make_pair(__first_ret, __first_ret);
1242  if (__ret.first != __last)
1243  std::advance(__ret.second, std::distance(std::get<0>(_M_m),
1244  std::get<1>(_M_m)));
1245  return __ret;
1246  }
1247 
1248  private:
1249  tuple<_ForwardIterator1, _ForwardIterator1, _BinaryPredicate> _M_m;
1250  };
1251 
1252 #ifdef __cpp_lib_boyer_moore_searcher // C++ >= 17 && HOSTED
1253 
1254  template<typename _Key, typename _Tp, typename _Hash, typename _Pred>
1255  struct __boyer_moore_map_base
1256  {
1257  template<typename _RAIter>
1258  __boyer_moore_map_base(_RAIter __pat, size_t __patlen,
1259  _Hash&& __hf, _Pred&& __pred)
1260  : _M_bad_char{ __patlen, std::move(__hf), std::move(__pred) }
1261  {
1262  if (__patlen > 0)
1263  for (__diff_type __i = 0; __i < __patlen - 1; ++__i)
1264  _M_bad_char[__pat[__i]] = __patlen - 1 - __i;
1265  }
1266 
1267  using __diff_type = _Tp;
1268 
1269  __diff_type
1270  _M_lookup(_Key __key, __diff_type __not_found) const
1271  {
1272  auto __iter = _M_bad_char.find(__key);
1273  if (__iter == _M_bad_char.end())
1274  return __not_found;
1275  return __iter->second;
1276  }
1277 
1278  _Pred
1279  _M_pred() const { return _M_bad_char.key_eq(); }
1280 
1281  _GLIBCXX_STD_C::unordered_map<_Key, _Tp, _Hash, _Pred> _M_bad_char;
1282  };
1283 
1284  template<typename _Tp, size_t _Len, typename _Pred>
1285  struct __boyer_moore_array_base
1286  {
1287  template<typename _RAIter, typename _Unused>
1288  __boyer_moore_array_base(_RAIter __pat, size_t __patlen,
1289  _Unused&&, _Pred&& __pred)
1290  : _M_bad_char{ array<_Tp, _Len>{}, std::move(__pred) }
1291  {
1292  std::get<0>(_M_bad_char).fill(__patlen);
1293  if (__patlen > 0)
1294  for (__diff_type __i = 0; __i < __patlen - 1; ++__i)
1295  {
1296  auto __ch = __pat[__i];
1297  using _UCh = make_unsigned_t<decltype(__ch)>;
1298  auto __uch = static_cast<_UCh>(__ch);
1299  std::get<0>(_M_bad_char)[__uch] = __patlen - 1 - __i;
1300  }
1301  }
1302 
1303  using __diff_type = _Tp;
1304 
1305  template<typename _Key>
1306  __diff_type
1307  _M_lookup(_Key __key, __diff_type __not_found) const
1308  {
1309  auto __ukey = static_cast<make_unsigned_t<_Key>>(__key);
1310  if (__ukey >= _Len)
1311  return __not_found;
1312  return std::get<0>(_M_bad_char)[__ukey];
1313  }
1314 
1315  const _Pred&
1316  _M_pred() const { return std::get<1>(_M_bad_char); }
1317 
1318  tuple<array<_Tp, _Len>, _Pred> _M_bad_char;
1319  };
1320 
1321  // Use __boyer_moore_array_base when pattern consists of narrow characters
1322  // (or std::byte) and uses std::equal_to as the predicate.
1323  template<typename _RAIter, typename _Hash, typename _Pred,
1324  typename _Val = typename iterator_traits<_RAIter>::value_type,
1325  typename _Diff = typename iterator_traits<_RAIter>::difference_type>
1326  using __boyer_moore_base_t
1327  = __conditional_t<__is_byte_like<_Val, _Pred>::value,
1328  __boyer_moore_array_base<_Diff, 256, _Pred>,
1329  __boyer_moore_map_base<_Val, _Diff, _Hash, _Pred>>;
1330 
1331  template<typename _RAIter, typename _Hash
1332  = hash<typename iterator_traits<_RAIter>::value_type>,
1333  typename _BinaryPredicate = equal_to<>>
1334  class boyer_moore_searcher
1335  : __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>
1336  {
1337  using _Base = __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>;
1338  using typename _Base::__diff_type;
1339 
1340  public:
1341  boyer_moore_searcher(_RAIter __pat_first, _RAIter __pat_last,
1342  _Hash __hf = _Hash(),
1343  _BinaryPredicate __pred = _BinaryPredicate());
1344 
1345  template<typename _RandomAccessIterator2>
1346  pair<_RandomAccessIterator2, _RandomAccessIterator2>
1347  operator()(_RandomAccessIterator2 __first,
1348  _RandomAccessIterator2 __last) const;
1349 
1350  private:
1351  bool
1352  _M_is_prefix(_RAIter __word, __diff_type __len,
1353  __diff_type __pos)
1354  {
1355  const auto& __pred = this->_M_pred();
1356  __diff_type __suffixlen = __len - __pos;
1357  for (__diff_type __i = 0; __i < __suffixlen; ++__i)
1358  if (!__pred(__word[__i], __word[__pos + __i]))
1359  return false;
1360  return true;
1361  }
1362 
1363  __diff_type
1364  _M_suffix_length(_RAIter __word, __diff_type __len,
1365  __diff_type __pos)
1366  {
1367  const auto& __pred = this->_M_pred();
1368  __diff_type __i = 0;
1369  while (__pred(__word[__pos - __i], __word[__len - 1 - __i])
1370  && __i < __pos)
1371  {
1372  ++__i;
1373  }
1374  return __i;
1375  }
1376 
1377  template<typename _Tp>
1378  __diff_type
1379  _M_bad_char_shift(_Tp __c) const
1380  { return this->_M_lookup(__c, _M_pat_end - _M_pat); }
1381 
1382  _RAIter _M_pat;
1383  _RAIter _M_pat_end;
1384  _GLIBCXX_STD_C::vector<__diff_type> _M_good_suffix;
1385  };
1386 
1387  template<typename _RAIter, typename _Hash
1388  = hash<typename iterator_traits<_RAIter>::value_type>,
1389  typename _BinaryPredicate = equal_to<>>
1390  class boyer_moore_horspool_searcher
1391  : __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>
1392  {
1393  using _Base = __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>;
1394  using typename _Base::__diff_type;
1395 
1396  public:
1397  boyer_moore_horspool_searcher(_RAIter __pat,
1398  _RAIter __pat_end,
1399  _Hash __hf = _Hash(),
1400  _BinaryPredicate __pred
1401  = _BinaryPredicate())
1402  : _Base(__pat, __pat_end - __pat, std::move(__hf), std::move(__pred)),
1403  _M_pat(__pat), _M_pat_end(__pat_end)
1404  { }
1405 
1406  template<typename _RandomAccessIterator2>
1407  pair<_RandomAccessIterator2, _RandomAccessIterator2>
1408  operator()(_RandomAccessIterator2 __first,
1409  _RandomAccessIterator2 __last) const
1410  {
1411  const auto& __pred = this->_M_pred();
1412  auto __patlen = _M_pat_end - _M_pat;
1413  if (__patlen == 0)
1414  return std::make_pair(__first, __first);
1415  auto __len = __last - __first;
1416  while (__len >= __patlen)
1417  {
1418  for (auto __scan = __patlen - 1;
1419  __pred(__first[__scan], _M_pat[__scan]); --__scan)
1420  if (__scan == 0)
1421  return std::make_pair(__first, __first + __patlen);
1422  auto __shift = _M_bad_char_shift(__first[__patlen - 1]);
1423  __len -= __shift;
1424  __first += __shift;
1425  }
1426  return std::make_pair(__last, __last);
1427  }
1428 
1429  private:
1430  template<typename _Tp>
1431  __diff_type
1432  _M_bad_char_shift(_Tp __c) const
1433  { return this->_M_lookup(__c, _M_pat_end - _M_pat); }
1434 
1435  _RAIter _M_pat;
1436  _RAIter _M_pat_end;
1437  };
1438 
1439  template<typename _RAIter, typename _Hash, typename _BinaryPredicate>
1440  boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>::
1441  boyer_moore_searcher(_RAIter __pat, _RAIter __pat_end,
1442  _Hash __hf, _BinaryPredicate __pred)
1443  : _Base(__pat, __pat_end - __pat, std::move(__hf), std::move(__pred)),
1444  _M_pat(__pat), _M_pat_end(__pat_end), _M_good_suffix(__pat_end - __pat)
1445  {
1446  auto __patlen = __pat_end - __pat;
1447  if (__patlen == 0)
1448  return;
1449  __diff_type __last_prefix = __patlen - 1;
1450  for (__diff_type __p = __patlen - 1; __p >= 0; --__p)
1451  {
1452  if (_M_is_prefix(__pat, __patlen, __p + 1))
1453  __last_prefix = __p + 1;
1454  _M_good_suffix[__p] = __last_prefix + (__patlen - 1 - __p);
1455  }
1456  for (__diff_type __p = 0; __p < __patlen - 1; ++__p)
1457  {
1458  auto __slen = _M_suffix_length(__pat, __patlen, __p);
1459  auto __pos = __patlen - 1 - __slen;
1460  if (!__pred(__pat[__p - __slen], __pat[__pos]))
1461  _M_good_suffix[__pos] = __patlen - 1 - __p + __slen;
1462  }
1463  }
1464 
1465  template<typename _RAIter, typename _Hash, typename _BinaryPredicate>
1466  template<typename _RandomAccessIterator2>
1467  pair<_RandomAccessIterator2, _RandomAccessIterator2>
1468  boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>::
1469  operator()(_RandomAccessIterator2 __first,
1470  _RandomAccessIterator2 __last) const
1471  {
1472  auto __patlen = _M_pat_end - _M_pat;
1473  if (__patlen == 0)
1474  return std::make_pair(__first, __first);
1475  const auto& __pred = this->_M_pred();
1476  __diff_type __i = __patlen - 1;
1477  auto __stringlen = __last - __first;
1478  while (__i < __stringlen)
1479  {
1480  __diff_type __j = __patlen - 1;
1481  while (__j >= 0 && __pred(__first[__i], _M_pat[__j]))
1482  {
1483  --__i;
1484  --__j;
1485  }
1486  if (__j < 0)
1487  {
1488  const auto __match = __first + __i + 1;
1489  return std::make_pair(__match, __match + __patlen);
1490  }
1491  __i += std::max(_M_bad_char_shift(__first[__i]),
1492  _M_good_suffix[__j]);
1493  }
1494  return std::make_pair(__last, __last);
1495  }
1496 #endif // __cpp_lib_boyer_moore_searcher
1497 
1498 #endif // C++17
1499 #endif // C++14
1500 #endif // C++11
1501 
1502 _GLIBCXX_END_NAMESPACE_VERSION
1503 } // namespace std
1504 
1505 #endif // _GLIBCXX_FUNCTIONAL