xref: /freebsd/contrib/llvm-project/libcxx/include/functional (revision 6580f5c38dd5b01aeeaed16b370f1a12423437f0)
1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_FUNCTIONAL
11#define _LIBCPP_FUNCTIONAL
12
13/*
14    functional synopsis
15
16namespace std
17{
18
19template <class Arg, class Result>
20struct unary_function
21{
22    typedef Arg    argument_type;
23    typedef Result result_type;
24};
25
26template <class Arg1, class Arg2, class Result>
27struct binary_function
28{
29    typedef Arg1   first_argument_type;
30    typedef Arg2   second_argument_type;
31    typedef Result result_type;
32};
33
34template <class T>
35class reference_wrapper
36    : public unary_function<T1, R> // if wrapping a unary functor
37    : public binary_function<T1, T2, R> // if wrapping a binary functor
38{
39public:
40    // types
41    typedef T type;
42    typedef see below result_type; // Not always defined
43
44    // construct/copy/destroy
45    template<class U>
46      constexpr reference_wrapper(U&&);                                   // constexpr since C++20
47    constexpr reference_wrapper(const reference_wrapper<T>& x) noexcept;  // constexpr since C++20
48
49    // assignment
50    constexpr reference_wrapper&
51    operator=(const reference_wrapper<T>& x) noexcept;                    // constexpr since C++20
52
53    // access
54    constexpr operator T& () const noexcept;                              // constexpr since C++20
55    constexpr T& get() const noexcept;                                    // constexpr since C++20
56
57    // invoke
58    template <class... ArgTypes>
59      constexpr typename result_of<T&(ArgTypes&&...)>::type               // constexpr since C++20
60          operator() (ArgTypes&&...) const
61              noexcept(is_nothrow_invocable_v<T&, ArgTypes...>);          // noexcept since C++17
62};
63
64template <class T>
65  reference_wrapper(T&) -> reference_wrapper<T>;
66
67template <class T> reference_wrapper<T> ref(T& t) noexcept;
68template <class T> void ref(const T&& t) = delete;
69template <class T> reference_wrapper<T> ref(reference_wrapper<T>t) noexcept;
70
71template <class T> reference_wrapper<const T> cref(const T& t) noexcept;
72template <class T> void cref(const T&& t) = delete;
73template <class T> reference_wrapper<const T> cref(reference_wrapper<T> t) noexcept;
74
75template <class T> struct unwrap_reference;                                       // since C++20
76template <class T> struct unwrap_ref_decay : unwrap_reference<decay_t<T>> { };    // since C++20
77template <class T> using unwrap_reference_t = typename unwrap_reference<T>::type; // since C++20
78template <class T> using unwrap_ref_decay_t = typename unwrap_ref_decay<T>::type; // since C++20
79
80template <class T> // <class T=void> in C++14
81struct plus {
82    T operator()(const T& x, const T& y) const;
83};
84
85template <class T> // <class T=void> in C++14
86struct minus {
87    T operator()(const T& x, const T& y) const;
88};
89
90template <class T> // <class T=void> in C++14
91struct multiplies {
92    T operator()(const T& x, const T& y) const;
93};
94
95template <class T> // <class T=void> in C++14
96struct divides {
97    T operator()(const T& x, const T& y) const;
98};
99
100template <class T> // <class T=void> in C++14
101struct modulus {
102    T operator()(const T& x, const T& y) const;
103};
104
105template <class T> // <class T=void> in C++14
106struct negate {
107    T operator()(const T& x) const;
108};
109
110template <class T> // <class T=void> in C++14
111struct equal_to {
112    bool operator()(const T& x, const T& y) const;
113};
114
115template <class T> // <class T=void> in C++14
116struct not_equal_to {
117    bool operator()(const T& x, const T& y) const;
118};
119
120template <class T> // <class T=void> in C++14
121struct greater {
122    bool operator()(const T& x, const T& y) const;
123};
124
125template <class T> // <class T=void> in C++14
126struct less {
127    bool operator()(const T& x, const T& y) const;
128};
129
130template <class T> // <class T=void> in C++14
131struct greater_equal {
132    bool operator()(const T& x, const T& y) const;
133};
134
135template <class T> // <class T=void> in C++14
136struct less_equal {
137    bool operator()(const T& x, const T& y) const;
138};
139
140// [comparisons.three.way], class compare_three_way
141struct compare_three_way;
142
143template <class T> // <class T=void> in C++14
144struct logical_and {
145    bool operator()(const T& x, const T& y) const;
146};
147
148template <class T> // <class T=void> in C++14
149struct logical_or {
150    bool operator()(const T& x, const T& y) const;
151};
152
153template <class T> // <class T=void> in C++14
154struct logical_not {
155    bool operator()(const T& x) const;
156};
157
158template <class T> // <class T=void> in C++14
159struct bit_and {
160    T operator()(const T& x, const T& y) const;
161};
162
163template <class T> // <class T=void> in C++14
164struct bit_or {
165    T operator()(const T& x, const T& y) const;
166};
167
168template <class T> // <class T=void> in C++14
169struct bit_xor {
170    T operator()(const T& x, const T& y) const;
171};
172
173template <class T=void> // C++14
174struct bit_not {
175    T operator()(const T& x) const;
176};
177
178struct identity; // C++20
179
180template <class Predicate>
181class unary_negate // deprecated in C++17, removed in C++20
182    : public unary_function<typename Predicate::argument_type, bool>
183{
184public:
185    explicit unary_negate(const Predicate& pred);
186    bool operator()(const typename Predicate::argument_type& x) const;
187};
188
189template <class Predicate> // deprecated in C++17, removed in C++20
190unary_negate<Predicate> not1(const Predicate& pred);
191
192template <class Predicate>
193class binary_negate // deprecated in C++17, removed in C++20
194    : public binary_function<typename Predicate::first_argument_type,
195                             typename Predicate::second_argument_type,
196                             bool>
197{
198public:
199    explicit binary_negate(const Predicate& pred);
200    bool operator()(const typename Predicate::first_argument_type& x,
201                    const typename Predicate::second_argument_type& y) const;
202};
203
204template <class Predicate> // deprecated in C++17, removed in C++20
205binary_negate<Predicate> not2(const Predicate& pred);
206
207template <class F>
208constexpr unspecified not_fn(F&& f); // C++17, constexpr in C++20
209
210template<class T> struct is_bind_expression;
211template<class T> struct is_placeholder;
212
213    // See C++14 20.9.9, Function object binders
214template <class T> inline constexpr bool is_bind_expression_v
215  = is_bind_expression<T>::value; // C++17
216template <class T> inline constexpr int is_placeholder_v
217  = is_placeholder<T>::value; // C++17
218
219
220template<class Fn, class... BoundArgs>
221  constexpr unspecified bind(Fn&&, BoundArgs&&...);  // constexpr in C++20
222template<class R, class Fn, class... BoundArgs>
223  constexpr unspecified bind(Fn&&, BoundArgs&&...);  // constexpr in C++20
224
225// [func.invoke]
226template<class F, class... Args>
227 constexpr // constexpr in C++20
228 invoke_result_t<F, Args...> invoke(F&& f, Args&&... args) // C++17
229    noexcept(is_nothrow_invocable_v<F, Args...>);
230
231template<class R, class F, class... Args>
232  constexpr R invoke_r(F&& f, Args&&... args)              // C++23
233    noexcept(is_nothrow_invocable_r_v<R, F, Args...>);
234
235namespace placeholders {
236  // M is the implementation-defined number of placeholders
237  extern unspecified _1;
238  extern unspecified _2;
239  .
240  .
241  .
242  extern unspecified _Mp;
243}
244
245template <class Operation>
246class binder1st     // deprecated in C++11, removed in C++17
247    : public unary_function<typename Operation::second_argument_type,
248                            typename Operation::result_type>
249{
250protected:
251    Operation                               op;
252    typename Operation::first_argument_type value;
253public:
254    binder1st(const Operation& x, const typename Operation::first_argument_type y);
255    typename Operation::result_type operator()(      typename Operation::second_argument_type& x) const;
256    typename Operation::result_type operator()(const typename Operation::second_argument_type& x) const;
257};
258
259template <class Operation, class T>
260binder1st<Operation> bind1st(const Operation& op, const T& x);                  // deprecated in C++11, removed in C++17
261
262template <class Operation>
263class binder2nd                                                                 // deprecated in C++11, removed in C++17
264    : public unary_function<typename Operation::first_argument_type,
265                            typename Operation::result_type>
266{
267protected:
268    Operation                                op;
269    typename Operation::second_argument_type value;
270public:
271    binder2nd(const Operation& x, const typename Operation::second_argument_type y);
272    typename Operation::result_type operator()(      typename Operation::first_argument_type& x) const;
273    typename Operation::result_type operator()(const typename Operation::first_argument_type& x) const;
274};
275
276template <class Operation, class T>
277binder2nd<Operation> bind2nd(const Operation& op, const T& x);                  // deprecated in C++11, removed in C++17
278
279template <class Arg, class Result>                                              // deprecated in C++11, removed in C++17
280class pointer_to_unary_function : public unary_function<Arg, Result>
281{
282public:
283    explicit pointer_to_unary_function(Result (*f)(Arg));
284    Result operator()(Arg x) const;
285};
286
287template <class Arg, class Result>
288pointer_to_unary_function<Arg,Result> ptr_fun(Result (*f)(Arg));                // deprecated in C++11, removed in C++17
289
290template <class Arg1, class Arg2, class Result>                                 // deprecated in C++11, removed in C++17
291class pointer_to_binary_function : public binary_function<Arg1, Arg2, Result>
292{
293public:
294    explicit pointer_to_binary_function(Result (*f)(Arg1, Arg2));
295    Result operator()(Arg1 x, Arg2 y) const;
296};
297
298template <class Arg1, class Arg2, class Result>
299pointer_to_binary_function<Arg1,Arg2,Result> ptr_fun(Result (*f)(Arg1,Arg2));   // deprecated in C++11, removed in C++17
300
301template<class S, class T>                                                      // deprecated in C++11, removed in C++17
302class mem_fun_t : public unary_function<T*, S>
303{
304public:
305    explicit mem_fun_t(S (T::*p)());
306    S operator()(T* p) const;
307};
308
309template<class S, class T, class A>
310class mem_fun1_t : public binary_function<T*, A, S>                             // deprecated in C++11, removed in C++17
311{
312public:
313    explicit mem_fun1_t(S (T::*p)(A));
314    S operator()(T* p, A x) const;
315};
316
317template<class S, class T>          mem_fun_t<S,T>    mem_fun(S (T::*f)());     // deprecated in C++11, removed in C++17
318template<class S, class T, class A> mem_fun1_t<S,T,A> mem_fun(S (T::*f)(A));    // deprecated in C++11, removed in C++17
319
320template<class S, class T>
321class mem_fun_ref_t : public unary_function<T, S>                               // deprecated in C++11, removed in C++17
322{
323public:
324    explicit mem_fun_ref_t(S (T::*p)());
325    S operator()(T& p) const;
326};
327
328template<class S, class T, class A>
329class mem_fun1_ref_t : public binary_function<T, A, S>                          // deprecated in C++11, removed in C++17
330{
331public:
332    explicit mem_fun1_ref_t(S (T::*p)(A));
333    S operator()(T& p, A x) const;
334};
335
336template<class S, class T>
337mem_fun_ref_t<S,T>    mem_fun_ref(S (T::*f)());                                 // deprecated in C++11, removed in C++17
338template<class S, class T, class A>
339mem_fun1_ref_t<S,T,A> mem_fun_ref(S (T::*f)(A));                                // deprecated in C++11, removed in C++17
340
341template <class S, class T>
342class const_mem_fun_t : public unary_function<const T*, S>                      // deprecated in C++11, removed in C++17
343{
344public:
345    explicit const_mem_fun_t(S (T::*p)() const);
346    S operator()(const T* p) const;
347};
348
349template <class S, class T, class A>
350class const_mem_fun1_t : public binary_function<const T*, A, S>                 // deprecated in C++11, removed in C++17
351{
352public:
353    explicit const_mem_fun1_t(S (T::*p)(A) const);
354    S operator()(const T* p, A x) const;
355};
356
357template <class S, class T>
358const_mem_fun_t<S,T>    mem_fun(S (T::*f)() const);                             // deprecated in C++11, removed in C++17
359template <class S, class T, class A>
360const_mem_fun1_t<S,T,A> mem_fun(S (T::*f)(A) const);                            // deprecated in C++11, removed in C++17
361
362template <class S, class T>
363class const_mem_fun_ref_t : public unary_function<T, S>                         // deprecated in C++11, removed in C++17
364{
365public:
366    explicit const_mem_fun_ref_t(S (T::*p)() const);
367    S operator()(const T& p) const;
368};
369
370template <class S, class T, class A>
371class const_mem_fun1_ref_t : public binary_function<T, A, S>                    // deprecated in C++11, removed in C++17
372{
373public:
374    explicit const_mem_fun1_ref_t(S (T::*p)(A) const);
375    S operator()(const T& p, A x) const;
376};
377
378template <class S, class T>
379const_mem_fun_ref_t<S,T>    mem_fun_ref(S (T::*f)() const);                     // deprecated in C++11, removed in C++17
380template <class S, class T, class A>
381const_mem_fun1_ref_t<S,T,A> mem_fun_ref(S (T::*f)(A) const);                    // deprecated in C++11, removed in C++17
382
383template<class R, class T> constexpr unspecified mem_fn(R T::*);                // constexpr in C++20
384
385class bad_function_call
386    : public exception
387{
388};
389
390template<class> class function; // undefined
391
392template<class R, class... ArgTypes>
393class function<R(ArgTypes...)>
394  : public unary_function<T1, R>      // iff sizeof...(ArgTypes) == 1 and
395                                      // ArgTypes contains T1
396  : public binary_function<T1, T2, R> // iff sizeof...(ArgTypes) == 2 and
397                                      // ArgTypes contains T1 and T2
398{
399public:
400    typedef R result_type;
401
402    // construct/copy/destroy:
403    function() noexcept;
404    function(nullptr_t) noexcept;
405    function(const function&);
406    function(function&&) noexcept;
407    template<class F>
408      function(F);
409    template<Allocator Alloc>
410      function(allocator_arg_t, const Alloc&) noexcept;            // removed in C++17
411    template<Allocator Alloc>
412      function(allocator_arg_t, const Alloc&, nullptr_t) noexcept; // removed in C++17
413    template<Allocator Alloc>
414      function(allocator_arg_t, const Alloc&, const function&);    // removed in C++17
415    template<Allocator Alloc>
416      function(allocator_arg_t, const Alloc&, function&&);         // removed in C++17
417    template<class F, Allocator Alloc>
418      function(allocator_arg_t, const Alloc&, F);                  // removed in C++17
419
420    function& operator=(const function&);
421    function& operator=(function&&) noexcept;
422    function& operator=(nullptr_t) noexcept;
423    template<class F>
424      function& operator=(F&&);
425    template<class F>
426      function& operator=(reference_wrapper<F>) noexcept;
427
428    ~function();
429
430    // function modifiers:
431    void swap(function&) noexcept;
432    template<class F, class Alloc>
433      void assign(F&&, const Alloc&);                 // Removed in C++17
434
435    // function capacity:
436    explicit operator bool() const noexcept;
437
438    // function invocation:
439    R operator()(ArgTypes...) const;
440
441    // function target access:
442    const std::type_info& target_type() const noexcept;
443    template <typename T>       T* target() noexcept;
444    template <typename T> const T* target() const noexcept;
445};
446
447// Deduction guides
448template<class R, class ...Args>
449function(R(*)(Args...)) -> function<R(Args...)>; // since C++17
450
451template<class F>
452function(F) -> function<see-below>; // since C++17
453
454// Null pointer comparisons:
455template <class R, class ... ArgTypes>
456  bool operator==(const function<R(ArgTypes...)>&, nullptr_t) noexcept;
457
458template <class R, class ... ArgTypes>
459  bool operator==(nullptr_t, const function<R(ArgTypes...)>&) noexcept; // removed in C++20
460
461template <class R, class ... ArgTypes>
462  bool operator!=(const function<R(ArgTypes...)>&, nullptr_t) noexcept; // removed in C++20
463
464template <class  R, class ... ArgTypes>
465  bool operator!=(nullptr_t, const function<R(ArgTypes...)>&) noexcept; // removed in C++20
466
467// specialized algorithms:
468template <class  R, class ... ArgTypes>
469  void swap(function<R(ArgTypes...)>&, function<R(ArgTypes...)>&) noexcept;
470
471template <class T> struct hash;
472
473template <> struct hash<bool>;
474template <> struct hash<char>;
475template <> struct hash<signed char>;
476template <> struct hash<unsigned char>;
477template <> struct hash<char8_t>; // since C++20
478template <> struct hash<char16_t>;
479template <> struct hash<char32_t>;
480template <> struct hash<wchar_t>;
481template <> struct hash<short>;
482template <> struct hash<unsigned short>;
483template <> struct hash<int>;
484template <> struct hash<unsigned int>;
485template <> struct hash<long>;
486template <> struct hash<long long>;
487template <> struct hash<unsigned long>;
488template <> struct hash<unsigned long long>;
489
490template <> struct hash<float>;
491template <> struct hash<double>;
492template <> struct hash<long double>;
493
494template<class T> struct hash<T*>;
495template <> struct hash<nullptr_t>;  // C++17
496
497namespace ranges {
498  // [range.cmp], concept-constrained comparisons
499  struct equal_to;
500  struct not_equal_to;
501  struct greater;
502  struct less;
503  struct greater_equal;
504  struct less_equal;
505}
506
507}  // std
508
509POLICY:  For non-variadic implementations, the number of arguments is limited
510         to 3.  It is hoped that the need for non-variadic implementations
511         will be minimal.
512
513*/
514
515#include <__algorithm/search.h>
516#include <__assert> // all public C++ headers provide the assertion handler
517#include <__compare/compare_three_way.h>
518#include <__config>
519#include <__functional/binary_function.h>
520#include <__functional/binary_negate.h>
521#include <__functional/bind.h>
522#include <__functional/bind_back.h>
523#include <__functional/bind_front.h>
524#include <__functional/binder1st.h>
525#include <__functional/binder2nd.h>
526#include <__functional/boyer_moore_searcher.h>
527#include <__functional/compose.h>
528#include <__functional/default_searcher.h>
529#include <__functional/function.h>
530#include <__functional/hash.h>
531#include <__functional/identity.h>
532#include <__functional/invoke.h>
533#include <__functional/mem_fn.h> // TODO: deprecate
534#include <__functional/mem_fun_ref.h>
535#include <__functional/not_fn.h>
536#include <__functional/operations.h>
537#include <__functional/pointer_to_binary_function.h>
538#include <__functional/pointer_to_unary_function.h>
539#include <__functional/ranges_operations.h>
540#include <__functional/reference_wrapper.h>
541#include <__functional/unary_function.h>
542#include <__functional/unary_negate.h>
543#include <__type_traits/unwrap_ref.h>
544#include <__utility/forward.h>
545#include <version>
546
547#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
548#  pragma GCC system_header
549#endif
550
551#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
552#  include <atomic>
553#  include <concepts>
554#  include <cstdlib>
555#  include <exception>
556#  include <iosfwd>
557#  include <memory>
558#  include <stdexcept>
559#  include <tuple>
560#  include <type_traits>
561#  include <typeinfo>
562#  include <utility>
563#endif
564
565#endif // _LIBCPP_FUNCTIONAL
566