1 // Functor implementations -*- C++ -*-
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51 /** @file bits/stl_function.h
52 * This is an internal header file, included by other library headers.
53 * Do not attempt to use it directly. @headername{functional}
56 #ifndef _STL_FUNCTION_H
57 #define _STL_FUNCTION_H 1
59 #if __cplusplus > 201103L
60 #include <bits/move.h>
63 namespace std _GLIBCXX_VISIBILITY(default)
65 _GLIBCXX_BEGIN_NAMESPACE_VERSION
67 // 20.3.1 base classes
68 /** @defgroup functors Function Objects
71 * Function objects, or @e functors, are objects with an @c operator()
72 * defined and accessible. They can be passed as arguments to algorithm
73 * templates and used in place of a function pointer. Not only is the
74 * resulting expressiveness of the library increased, but the generated
75 * code can be more efficient than what you might write by hand. When we
76 * refer to @a functors, then, generally we include function pointers in
77 * the description as well.
79 * Often, functors are only created as temporaries passed to algorithm
80 * calls, rather than being created as named variables.
82 * Two examples taken from the standard itself follow. To perform a
83 * by-element addition of two vectors @c a and @c b containing @c double,
84 * and put the result in @c a, use
86 * transform (a.begin(), a.end(), b.begin(), a.begin(), plus<double>());
88 * To negate every element in @c a, use
90 * transform(a.begin(), a.end(), a.begin(), negate<double>());
92 * The addition and negation functions will be inlined directly.
94 * The standard functors are derived from structs named @c unary_function
95 * and @c binary_function. These two classes contain nothing but typedefs,
96 * to aid in generic (template) programming. If you write your own
97 * functors, you might consider doing the same.
102 * This is one of the @link functors functor base classes@endlink.
104 template<typename _Arg, typename _Result>
105 struct unary_function
107 /// @c argument_type is the type of the argument
108 typedef _Arg argument_type;
110 /// @c result_type is the return type
111 typedef _Result result_type;
115 * This is one of the @link functors functor base classes@endlink.
117 template<typename _Arg1, typename _Arg2, typename _Result>
118 struct binary_function
120 /// @c first_argument_type is the type of the first argument
121 typedef _Arg1 first_argument_type;
123 /// @c second_argument_type is the type of the second argument
124 typedef _Arg2 second_argument_type;
126 /// @c result_type is the return type
127 typedef _Result result_type;
132 /** @defgroup arithmetic_functors Arithmetic Classes
135 * Because basic math often needs to be done during an algorithm,
136 * the library provides functors for those operations. See the
137 * documentation for @link functors the base classes@endlink
138 * for examples of their use.
143 #if __cplusplus > 201103L
144 struct __is_transparent; // undefined
146 template<typename _Tp = void>
149 template<typename _Tp = void>
152 template<typename _Tp = void>
155 template<typename _Tp = void>
158 template<typename _Tp = void>
161 template<typename _Tp = void>
165 /// One of the @link arithmetic_functors math functors@endlink.
166 template<typename _Tp>
167 struct plus : public binary_function<_Tp, _Tp, _Tp>
171 operator()(const _Tp& __x, const _Tp& __y) const
172 { return __x + __y; }
175 /// One of the @link arithmetic_functors math functors@endlink.
176 template<typename _Tp>
177 struct minus : public binary_function<_Tp, _Tp, _Tp>
181 operator()(const _Tp& __x, const _Tp& __y) const
182 { return __x - __y; }
185 /// One of the @link arithmetic_functors math functors@endlink.
186 template<typename _Tp>
187 struct multiplies : public binary_function<_Tp, _Tp, _Tp>
191 operator()(const _Tp& __x, const _Tp& __y) const
192 { return __x * __y; }
195 /// One of the @link arithmetic_functors math functors@endlink.
196 template<typename _Tp>
197 struct divides : public binary_function<_Tp, _Tp, _Tp>
201 operator()(const _Tp& __x, const _Tp& __y) const
202 { return __x / __y; }
205 /// One of the @link arithmetic_functors math functors@endlink.
206 template<typename _Tp>
207 struct modulus : public binary_function<_Tp, _Tp, _Tp>
211 operator()(const _Tp& __x, const _Tp& __y) const
212 { return __x % __y; }
215 /// One of the @link arithmetic_functors math functors@endlink.
216 template<typename _Tp>
217 struct negate : public unary_function<_Tp, _Tp>
221 operator()(const _Tp& __x) const
225 #if __cplusplus > 201103L
227 #define __cpp_lib_transparent_operators 201210
228 //#define __cpp_lib_generic_associative_lookup 201304
233 template <typename _Tp, typename _Up>
236 operator()(_Tp&& __t, _Up&& __u) const
237 noexcept(noexcept(std::forward<_Tp>(__t) + std::forward<_Up>(__u)))
238 -> decltype(std::forward<_Tp>(__t) + std::forward<_Up>(__u))
239 { return std::forward<_Tp>(__t) + std::forward<_Up>(__u); }
241 typedef __is_transparent is_transparent;
244 /// One of the @link arithmetic_functors math functors@endlink.
248 template <typename _Tp, typename _Up>
251 operator()(_Tp&& __t, _Up&& __u) const
252 noexcept(noexcept(std::forward<_Tp>(__t) - std::forward<_Up>(__u)))
253 -> decltype(std::forward<_Tp>(__t) - std::forward<_Up>(__u))
254 { return std::forward<_Tp>(__t) - std::forward<_Up>(__u); }
256 typedef __is_transparent is_transparent;
259 /// One of the @link arithmetic_functors math functors@endlink.
261 struct multiplies<void>
263 template <typename _Tp, typename _Up>
266 operator()(_Tp&& __t, _Up&& __u) const
267 noexcept(noexcept(std::forward<_Tp>(__t) * std::forward<_Up>(__u)))
268 -> decltype(std::forward<_Tp>(__t) * std::forward<_Up>(__u))
269 { return std::forward<_Tp>(__t) * std::forward<_Up>(__u); }
271 typedef __is_transparent is_transparent;
274 /// One of the @link arithmetic_functors math functors@endlink.
278 template <typename _Tp, typename _Up>
281 operator()(_Tp&& __t, _Up&& __u) const
282 noexcept(noexcept(std::forward<_Tp>(__t) / std::forward<_Up>(__u)))
283 -> decltype(std::forward<_Tp>(__t) / std::forward<_Up>(__u))
284 { return std::forward<_Tp>(__t) / std::forward<_Up>(__u); }
286 typedef __is_transparent is_transparent;
289 /// One of the @link arithmetic_functors math functors@endlink.
293 template <typename _Tp, typename _Up>
296 operator()(_Tp&& __t, _Up&& __u) const
297 noexcept(noexcept(std::forward<_Tp>(__t) % std::forward<_Up>(__u)))
298 -> decltype(std::forward<_Tp>(__t) % std::forward<_Up>(__u))
299 { return std::forward<_Tp>(__t) % std::forward<_Up>(__u); }
301 typedef __is_transparent is_transparent;
304 /// One of the @link arithmetic_functors math functors@endlink.
308 template <typename _Tp>
311 operator()(_Tp&& __t) const
312 noexcept(noexcept(-std::forward<_Tp>(__t)))
313 -> decltype(-std::forward<_Tp>(__t))
314 { return -std::forward<_Tp>(__t); }
316 typedef __is_transparent is_transparent;
321 // 20.3.3 comparisons
322 /** @defgroup comparison_functors Comparison Classes
325 * The library provides six wrapper functors for all the basic comparisons
330 #if __cplusplus > 201103L
331 template<typename _Tp = void>
334 template<typename _Tp = void>
337 template<typename _Tp = void>
340 template<typename _Tp = void>
343 template<typename _Tp = void>
344 struct greater_equal;
346 template<typename _Tp = void>
350 /// One of the @link comparison_functors comparison functors@endlink.
351 template<typename _Tp>
352 struct equal_to : public binary_function<_Tp, _Tp, bool>
356 operator()(const _Tp& __x, const _Tp& __y) const
357 { return __x == __y; }
360 /// One of the @link comparison_functors comparison functors@endlink.
361 template<typename _Tp>
362 struct not_equal_to : public binary_function<_Tp, _Tp, bool>
366 operator()(const _Tp& __x, const _Tp& __y) const
367 { return __x != __y; }
370 /// One of the @link comparison_functors comparison functors@endlink.
371 template<typename _Tp>
372 struct greater : public binary_function<_Tp, _Tp, bool>
376 operator()(const _Tp& __x, const _Tp& __y) const
377 { return __x > __y; }
380 /// One of the @link comparison_functors comparison functors@endlink.
381 template<typename _Tp>
382 struct less : public binary_function<_Tp, _Tp, bool>
386 operator()(const _Tp& __x, const _Tp& __y) const
387 { return __x < __y; }
390 /// One of the @link comparison_functors comparison functors@endlink.
391 template<typename _Tp>
392 struct greater_equal : public binary_function<_Tp, _Tp, bool>
396 operator()(const _Tp& __x, const _Tp& __y) const
397 { return __x >= __y; }
400 /// One of the @link comparison_functors comparison functors@endlink.
401 template<typename _Tp>
402 struct less_equal : public binary_function<_Tp, _Tp, bool>
406 operator()(const _Tp& __x, const _Tp& __y) const
407 { return __x <= __y; }
410 #if __cplusplus > 201103L
411 /// One of the @link comparison_functors comparison functors@endlink.
413 struct equal_to<void>
415 template <typename _Tp, typename _Up>
418 operator()(_Tp&& __t, _Up&& __u) const
419 noexcept(noexcept(std::forward<_Tp>(__t) == std::forward<_Up>(__u)))
420 -> decltype(std::forward<_Tp>(__t) == std::forward<_Up>(__u))
421 { return std::forward<_Tp>(__t) == std::forward<_Up>(__u); }
423 typedef __is_transparent is_transparent;
426 /// One of the @link comparison_functors comparison functors@endlink.
428 struct not_equal_to<void>
430 template <typename _Tp, typename _Up>
433 operator()(_Tp&& __t, _Up&& __u) const
434 noexcept(noexcept(std::forward<_Tp>(__t) != std::forward<_Up>(__u)))
435 -> decltype(std::forward<_Tp>(__t) != std::forward<_Up>(__u))
436 { return std::forward<_Tp>(__t) != std::forward<_Up>(__u); }
438 typedef __is_transparent is_transparent;
441 /// One of the @link comparison_functors comparison functors@endlink.
445 template <typename _Tp, typename _Up>
448 operator()(_Tp&& __t, _Up&& __u) const
449 noexcept(noexcept(std::forward<_Tp>(__t) > std::forward<_Up>(__u)))
450 -> decltype(std::forward<_Tp>(__t) > std::forward<_Up>(__u))
451 { return std::forward<_Tp>(__t) > std::forward<_Up>(__u); }
453 typedef __is_transparent is_transparent;
456 /// One of the @link comparison_functors comparison functors@endlink.
460 template <typename _Tp, typename _Up>
463 operator()(_Tp&& __t, _Up&& __u) const
464 noexcept(noexcept(std::forward<_Tp>(__t) < std::forward<_Up>(__u)))
465 -> decltype(std::forward<_Tp>(__t) < std::forward<_Up>(__u))
466 { return std::forward<_Tp>(__t) < std::forward<_Up>(__u); }
468 typedef __is_transparent is_transparent;
471 /// One of the @link comparison_functors comparison functors@endlink.
473 struct greater_equal<void>
475 template <typename _Tp, typename _Up>
478 operator()(_Tp&& __t, _Up&& __u) const
479 noexcept(noexcept(std::forward<_Tp>(__t) >= std::forward<_Up>(__u)))
480 -> decltype(std::forward<_Tp>(__t) >= std::forward<_Up>(__u))
481 { return std::forward<_Tp>(__t) >= std::forward<_Up>(__u); }
483 typedef __is_transparent is_transparent;
486 /// One of the @link comparison_functors comparison functors@endlink.
488 struct less_equal<void>
490 template <typename _Tp, typename _Up>
493 operator()(_Tp&& __t, _Up&& __u) const
494 noexcept(noexcept(std::forward<_Tp>(__t) <= std::forward<_Up>(__u)))
495 -> decltype(std::forward<_Tp>(__t) <= std::forward<_Up>(__u))
496 { return std::forward<_Tp>(__t) <= std::forward<_Up>(__u); }
498 typedef __is_transparent is_transparent;
503 // 20.3.4 logical operations
504 /** @defgroup logical_functors Boolean Operations Classes
507 * Here are wrapper functors for Boolean operations: @c &&, @c ||,
512 #if __cplusplus > 201103L
513 template<typename _Tp = void>
516 template<typename _Tp = void>
519 template<typename _Tp = void>
523 /// One of the @link logical_functors Boolean operations functors@endlink.
524 template<typename _Tp>
525 struct logical_and : public binary_function<_Tp, _Tp, bool>
529 operator()(const _Tp& __x, const _Tp& __y) const
530 { return __x && __y; }
533 /// One of the @link logical_functors Boolean operations functors@endlink.
534 template<typename _Tp>
535 struct logical_or : public binary_function<_Tp, _Tp, bool>
539 operator()(const _Tp& __x, const _Tp& __y) const
540 { return __x || __y; }
543 /// One of the @link logical_functors Boolean operations functors@endlink.
544 template<typename _Tp>
545 struct logical_not : public unary_function<_Tp, bool>
549 operator()(const _Tp& __x) const
553 #if __cplusplus > 201103L
554 /// One of the @link logical_functors Boolean operations functors@endlink.
556 struct logical_and<void>
558 template <typename _Tp, typename _Up>
561 operator()(_Tp&& __t, _Up&& __u) const
562 noexcept(noexcept(std::forward<_Tp>(__t) && std::forward<_Up>(__u)))
563 -> decltype(std::forward<_Tp>(__t) && std::forward<_Up>(__u))
564 { return std::forward<_Tp>(__t) && std::forward<_Up>(__u); }
566 typedef __is_transparent is_transparent;
569 /// One of the @link logical_functors Boolean operations functors@endlink.
571 struct logical_or<void>
573 template <typename _Tp, typename _Up>
576 operator()(_Tp&& __t, _Up&& __u) const
577 noexcept(noexcept(std::forward<_Tp>(__t) || std::forward<_Up>(__u)))
578 -> decltype(std::forward<_Tp>(__t) || std::forward<_Up>(__u))
579 { return std::forward<_Tp>(__t) || std::forward<_Up>(__u); }
581 typedef __is_transparent is_transparent;
584 /// One of the @link logical_functors Boolean operations functors@endlink.
586 struct logical_not<void>
588 template <typename _Tp>
591 operator()(_Tp&& __t) const
592 noexcept(noexcept(!std::forward<_Tp>(__t)))
593 -> decltype(!std::forward<_Tp>(__t))
594 { return !std::forward<_Tp>(__t); }
596 typedef __is_transparent is_transparent;
601 #if __cplusplus > 201103L
602 template<typename _Tp = void>
605 template<typename _Tp = void>
608 template<typename _Tp = void>
611 template<typename _Tp = void>
615 // _GLIBCXX_RESOLVE_LIB_DEFECTS
616 // DR 660. Missing Bitwise Operations.
617 template<typename _Tp>
618 struct bit_and : public binary_function<_Tp, _Tp, _Tp>
622 operator()(const _Tp& __x, const _Tp& __y) const
623 { return __x & __y; }
626 template<typename _Tp>
627 struct bit_or : public binary_function<_Tp, _Tp, _Tp>
631 operator()(const _Tp& __x, const _Tp& __y) const
632 { return __x | __y; }
635 template<typename _Tp>
636 struct bit_xor : public binary_function<_Tp, _Tp, _Tp>
640 operator()(const _Tp& __x, const _Tp& __y) const
641 { return __x ^ __y; }
644 template<typename _Tp>
645 struct bit_not : public unary_function<_Tp, _Tp>
649 operator()(const _Tp& __x) const
653 #if __cplusplus > 201103L
657 template <typename _Tp, typename _Up>
660 operator()(_Tp&& __t, _Up&& __u) const
661 noexcept(noexcept(std::forward<_Tp>(__t) & std::forward<_Up>(__u)))
662 -> decltype(std::forward<_Tp>(__t) & std::forward<_Up>(__u))
663 { return std::forward<_Tp>(__t) & std::forward<_Up>(__u); }
665 typedef __is_transparent is_transparent;
671 template <typename _Tp, typename _Up>
674 operator()(_Tp&& __t, _Up&& __u) const
675 noexcept(noexcept(std::forward<_Tp>(__t) | std::forward<_Up>(__u)))
676 -> decltype(std::forward<_Tp>(__t) | std::forward<_Up>(__u))
677 { return std::forward<_Tp>(__t) | std::forward<_Up>(__u); }
679 typedef __is_transparent is_transparent;
685 template <typename _Tp, typename _Up>
688 operator()(_Tp&& __t, _Up&& __u) const
689 noexcept(noexcept(std::forward<_Tp>(__t) ^ std::forward<_Up>(__u)))
690 -> decltype(std::forward<_Tp>(__t) ^ std::forward<_Up>(__u))
691 { return std::forward<_Tp>(__t) ^ std::forward<_Up>(__u); }
693 typedef __is_transparent is_transparent;
699 template <typename _Tp>
702 operator()(_Tp&& __t) const
703 noexcept(noexcept(~std::forward<_Tp>(__t)))
704 -> decltype(~std::forward<_Tp>(__t))
705 { return ~std::forward<_Tp>(__t); }
707 typedef __is_transparent is_transparent;
712 /** @defgroup negators Negators
715 * The functions @c not1 and @c not2 each take a predicate functor
716 * and return an instance of @c unary_negate or
717 * @c binary_negate, respectively. These classes are functors whose
718 * @c operator() performs the stored predicate function and then returns
719 * the negation of the result.
721 * For example, given a vector of integers and a trivial predicate,
723 * struct IntGreaterThanThree
724 * : public std::unary_function<int, bool>
726 * bool operator() (int x) { return x > 3; }
729 * std::find_if (v.begin(), v.end(), not1(IntGreaterThanThree()));
731 * The call to @c find_if will locate the first index (i) of @c v for which
732 * <code>!(v[i] > 3)</code> is true.
734 * The not1/unary_negate combination works on predicates taking a single
735 * argument. The not2/binary_negate combination works on predicates which
736 * take two arguments.
740 /// One of the @link negators negation functors@endlink.
741 template<typename _Predicate>
743 : public unary_function<typename _Predicate::argument_type, bool>
751 unary_negate(const _Predicate& __x) : _M_pred(__x) { }
755 operator()(const typename _Predicate::argument_type& __x) const
756 { return !_M_pred(__x); }
759 /// One of the @link negators negation functors@endlink.
760 template<typename _Predicate>
762 inline unary_negate<_Predicate>
763 not1(const _Predicate& __pred)
764 { return unary_negate<_Predicate>(__pred); }
766 /// One of the @link negators negation functors@endlink.
767 template<typename _Predicate>
769 : public binary_function<typename _Predicate::first_argument_type,
770 typename _Predicate::second_argument_type, bool>
778 binary_negate(const _Predicate& __x) : _M_pred(__x) { }
782 operator()(const typename _Predicate::first_argument_type& __x,
783 const typename _Predicate::second_argument_type& __y) const
784 { return !_M_pred(__x, __y); }
787 /// One of the @link negators negation functors@endlink.
788 template<typename _Predicate>
790 inline binary_negate<_Predicate>
791 not2(const _Predicate& __pred)
792 { return binary_negate<_Predicate>(__pred); }
795 // 20.3.7 adaptors pointers functions
796 /** @defgroup pointer_adaptors Adaptors for pointers to functions
799 * The advantage of function objects over pointers to functions is that
800 * the objects in the standard library declare nested typedefs describing
801 * their argument and result types with uniform names (e.g., @c result_type
802 * from the base classes @c unary_function and @c binary_function).
803 * Sometimes those typedefs are required, not just optional.
805 * Adaptors are provided to turn pointers to unary (single-argument) and
806 * binary (double-argument) functions into function objects. The
807 * long-winded functor @c pointer_to_unary_function is constructed with a
808 * function pointer @c f, and its @c operator() called with argument @c x
809 * returns @c f(x). The functor @c pointer_to_binary_function does the same
810 * thing, but with a double-argument @c f and @c operator().
812 * The function @c ptr_fun takes a pointer-to-function @c f and constructs
813 * an instance of the appropriate functor.
817 /// One of the @link pointer_adaptors adaptors for function pointers@endlink.
818 template<typename _Arg, typename _Result>
819 class pointer_to_unary_function : public unary_function<_Arg, _Result>
822 _Result (*_M_ptr)(_Arg);
825 pointer_to_unary_function() { }
828 pointer_to_unary_function(_Result (*__x)(_Arg))
832 operator()(_Arg __x) const
833 { return _M_ptr(__x); }
836 /// One of the @link pointer_adaptors adaptors for function pointers@endlink.
837 template<typename _Arg, typename _Result>
838 inline pointer_to_unary_function<_Arg, _Result>
839 ptr_fun(_Result (*__x)(_Arg))
840 { return pointer_to_unary_function<_Arg, _Result>(__x); }
842 /// One of the @link pointer_adaptors adaptors for function pointers@endlink.
843 template<typename _Arg1, typename _Arg2, typename _Result>
844 class pointer_to_binary_function
845 : public binary_function<_Arg1, _Arg2, _Result>
848 _Result (*_M_ptr)(_Arg1, _Arg2);
851 pointer_to_binary_function() { }
854 pointer_to_binary_function(_Result (*__x)(_Arg1, _Arg2))
858 operator()(_Arg1 __x, _Arg2 __y) const
859 { return _M_ptr(__x, __y); }
862 /// One of the @link pointer_adaptors adaptors for function pointers@endlink.
863 template<typename _Arg1, typename _Arg2, typename _Result>
864 inline pointer_to_binary_function<_Arg1, _Arg2, _Result>
865 ptr_fun(_Result (*__x)(_Arg1, _Arg2))
866 { return pointer_to_binary_function<_Arg1, _Arg2, _Result>(__x); }
869 template<typename _Tp>
871 : public unary_function<_Tp,_Tp>
874 operator()(_Tp& __x) const
878 operator()(const _Tp& __x) const
882 template<typename _Pair>
884 : public unary_function<_Pair, typename _Pair::first_type>
886 typename _Pair::first_type&
887 operator()(_Pair& __x) const
888 { return __x.first; }
890 const typename _Pair::first_type&
891 operator()(const _Pair& __x) const
892 { return __x.first; }
894 #if __cplusplus >= 201103L
895 template<typename _Pair2>
896 typename _Pair2::first_type&
897 operator()(_Pair2& __x) const
898 { return __x.first; }
900 template<typename _Pair2>
901 const typename _Pair2::first_type&
902 operator()(const _Pair2& __x) const
903 { return __x.first; }
907 template<typename _Pair>
909 : public unary_function<_Pair, typename _Pair::second_type>
911 typename _Pair::second_type&
912 operator()(_Pair& __x) const
913 { return __x.second; }
915 const typename _Pair::second_type&
916 operator()(const _Pair& __x) const
917 { return __x.second; }
920 // 20.3.8 adaptors pointers members
921 /** @defgroup memory_adaptors Adaptors for pointers to members
924 * There are a total of 8 = 2^3 function objects in this family.
925 * (1) Member functions taking no arguments vs member functions taking
927 * (2) Call through pointer vs call through reference.
928 * (3) Const vs non-const member function.
930 * All of this complexity is in the function objects themselves. You can
931 * ignore it by using the helper function mem_fun and mem_fun_ref,
932 * which create whichever type of adaptor is appropriate.
936 /// One of the @link memory_adaptors adaptors for member
937 /// pointers@endlink.
938 template<typename _Ret, typename _Tp>
939 class mem_fun_t : public unary_function<_Tp*, _Ret>
943 mem_fun_t(_Ret (_Tp::*__pf)())
947 operator()(_Tp* __p) const
948 { return (__p->*_M_f)(); }
954 /// One of the @link memory_adaptors adaptors for member
955 /// pointers@endlink.
956 template<typename _Ret, typename _Tp>
957 class const_mem_fun_t : public unary_function<const _Tp*, _Ret>
961 const_mem_fun_t(_Ret (_Tp::*__pf)() const)
965 operator()(const _Tp* __p) const
966 { return (__p->*_M_f)(); }
969 _Ret (_Tp::*_M_f)() const;
972 /// One of the @link memory_adaptors adaptors for member
973 /// pointers@endlink.
974 template<typename _Ret, typename _Tp>
975 class mem_fun_ref_t : public unary_function<_Tp, _Ret>
979 mem_fun_ref_t(_Ret (_Tp::*__pf)())
983 operator()(_Tp& __r) const
984 { return (__r.*_M_f)(); }
990 /// One of the @link memory_adaptors adaptors for member
991 /// pointers@endlink.
992 template<typename _Ret, typename _Tp>
993 class const_mem_fun_ref_t : public unary_function<_Tp, _Ret>
997 const_mem_fun_ref_t(_Ret (_Tp::*__pf)() const)
1001 operator()(const _Tp& __r) const
1002 { return (__r.*_M_f)(); }
1005 _Ret (_Tp::*_M_f)() const;
1008 /// One of the @link memory_adaptors adaptors for member
1009 /// pointers@endlink.
1010 template<typename _Ret, typename _Tp, typename _Arg>
1011 class mem_fun1_t : public binary_function<_Tp*, _Arg, _Ret>
1015 mem_fun1_t(_Ret (_Tp::*__pf)(_Arg))
1019 operator()(_Tp* __p, _Arg __x) const
1020 { return (__p->*_M_f)(__x); }
1023 _Ret (_Tp::*_M_f)(_Arg);
1026 /// One of the @link memory_adaptors adaptors for member
1027 /// pointers@endlink.
1028 template<typename _Ret, typename _Tp, typename _Arg>
1029 class const_mem_fun1_t : public binary_function<const _Tp*, _Arg, _Ret>
1033 const_mem_fun1_t(_Ret (_Tp::*__pf)(_Arg) const)
1037 operator()(const _Tp* __p, _Arg __x) const
1038 { return (__p->*_M_f)(__x); }
1041 _Ret (_Tp::*_M_f)(_Arg) const;
1044 /// One of the @link memory_adaptors adaptors for member
1045 /// pointers@endlink.
1046 template<typename _Ret, typename _Tp, typename _Arg>
1047 class mem_fun1_ref_t : public binary_function<_Tp, _Arg, _Ret>
1051 mem_fun1_ref_t(_Ret (_Tp::*__pf)(_Arg))
1055 operator()(_Tp& __r, _Arg __x) const
1056 { return (__r.*_M_f)(__x); }
1059 _Ret (_Tp::*_M_f)(_Arg);
1062 /// One of the @link memory_adaptors adaptors for member
1063 /// pointers@endlink.
1064 template<typename _Ret, typename _Tp, typename _Arg>
1065 class const_mem_fun1_ref_t : public binary_function<_Tp, _Arg, _Ret>
1069 const_mem_fun1_ref_t(_Ret (_Tp::*__pf)(_Arg) const)
1073 operator()(const _Tp& __r, _Arg __x) const
1074 { return (__r.*_M_f)(__x); }
1077 _Ret (_Tp::*_M_f)(_Arg) const;
1080 // Mem_fun adaptor helper functions. There are only two:
1081 // mem_fun and mem_fun_ref.
1082 template<typename _Ret, typename _Tp>
1083 inline mem_fun_t<_Ret, _Tp>
1084 mem_fun(_Ret (_Tp::*__f)())
1085 { return mem_fun_t<_Ret, _Tp>(__f); }
1087 template<typename _Ret, typename _Tp>
1088 inline const_mem_fun_t<_Ret, _Tp>
1089 mem_fun(_Ret (_Tp::*__f)() const)
1090 { return const_mem_fun_t<_Ret, _Tp>(__f); }
1092 template<typename _Ret, typename _Tp>
1093 inline mem_fun_ref_t<_Ret, _Tp>
1094 mem_fun_ref(_Ret (_Tp::*__f)())
1095 { return mem_fun_ref_t<_Ret, _Tp>(__f); }
1097 template<typename _Ret, typename _Tp>
1098 inline const_mem_fun_ref_t<_Ret, _Tp>
1099 mem_fun_ref(_Ret (_Tp::*__f)() const)
1100 { return const_mem_fun_ref_t<_Ret, _Tp>(__f); }
1102 template<typename _Ret, typename _Tp, typename _Arg>
1103 inline mem_fun1_t<_Ret, _Tp, _Arg>
1104 mem_fun(_Ret (_Tp::*__f)(_Arg))
1105 { return mem_fun1_t<_Ret, _Tp, _Arg>(__f); }
1107 template<typename _Ret, typename _Tp, typename _Arg>
1108 inline const_mem_fun1_t<_Ret, _Tp, _Arg>
1109 mem_fun(_Ret (_Tp::*__f)(_Arg) const)
1110 { return const_mem_fun1_t<_Ret, _Tp, _Arg>(__f); }
1112 template<typename _Ret, typename _Tp, typename _Arg>
1113 inline mem_fun1_ref_t<_Ret, _Tp, _Arg>
1114 mem_fun_ref(_Ret (_Tp::*__f)(_Arg))
1115 { return mem_fun1_ref_t<_Ret, _Tp, _Arg>(__f); }
1117 template<typename _Ret, typename _Tp, typename _Arg>
1118 inline const_mem_fun1_ref_t<_Ret, _Tp, _Arg>
1119 mem_fun_ref(_Ret (_Tp::*__f)(_Arg) const)
1120 { return const_mem_fun1_ref_t<_Ret, _Tp, _Arg>(__f); }
1124 _GLIBCXX_END_NAMESPACE_VERSION
1127 #if (__cplusplus < 201103L) || _GLIBCXX_USE_DEPRECATED
1128 # include <backward/binders.h>
1131 #endif /* _STL_FUNCTION_H */