[thirdparty/gcc.git] / libstdc++-v3 / include / std / utility

// <utility> -*- C++ -*-

// Copyright (C) 2001-2020 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.

// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.

/*
 *
 * Copyright (c) 1994
 * Hewlett-Packard Company
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Hewlett-Packard Company makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 *
 * Copyright (c) 1996,1997
 * Silicon Graphics Computer Systems, Inc.
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Silicon Graphics makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 */

/** @file include/utility
 *  This is a Standard C++ Library header.
 */

#ifndef _GLIBCXX_UTILITY
#define _GLIBCXX_UTILITY 1

#pragma GCC system_header

/**
 * @defgroup utilities Utilities
 *
 * Components deemed generally useful. Includes pair, tuple,
 * forward/move helpers, ratio, function object, metaprogramming and
 * type traits, time, date, and memory functions.
 */

#include <bits/c++config.h>
#include <bits/stl_relops.h>
#include <bits/stl_pair.h>

#if __cplusplus >= 201103L

#include <type_traits>
#include <bits/move.h>
#include <initializer_list>

namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION

  /// Finds the size of a given tuple type.
  template<typename _Tp>
    struct tuple_size;

  // _GLIBCXX_RESOLVE_LIB_DEFECTS
  // 2313. tuple_size should always derive from integral_constant<size_t, N>
  // 2770. tuple_size<const T> specialization is not SFINAE compatible

  template<typename _Tp,
	   typename _Up = typename remove_cv<_Tp>::type,
	   typename = typename enable_if<is_same<_Tp, _Up>::value>::type,
	   size_t = tuple_size<_Tp>::value>
    using __enable_if_has_tuple_size = _Tp;

  template<typename _Tp>
    struct tuple_size<const __enable_if_has_tuple_size<_Tp>>
    : public tuple_size<_Tp> { };

  template<typename _Tp>
    struct tuple_size<volatile __enable_if_has_tuple_size<_Tp>>
    : public tuple_size<_Tp> { };

  template<typename _Tp>
    struct tuple_size<const volatile __enable_if_has_tuple_size<_Tp>>
    : public tuple_size<_Tp> { };

  /// Gives the type of the ith element of a given tuple type.
  template<std::size_t __i, typename _Tp>
    struct tuple_element;

  // Duplicate of C++14's tuple_element_t for internal use in C++11 mode
  template<std::size_t __i, typename _Tp>
    using __tuple_element_t = typename tuple_element<__i, _Tp>::type;

  template<std::size_t __i, typename _Tp>
    struct tuple_element<__i, const _Tp>
    {
      typedef typename add_const<__tuple_element_t<__i, _Tp>>::type type;
    };

  template<std::size_t __i, typename _Tp>
    struct tuple_element<__i, volatile _Tp>
    {
      typedef typename add_volatile<__tuple_element_t<__i, _Tp>>::type type;
    };

  template<std::size_t __i, typename _Tp>
    struct tuple_element<__i, const volatile _Tp>
    {
      typedef typename add_cv<__tuple_element_t<__i, _Tp>>::type type;
    };

#if __cplusplus >= 201402L
// The standard says this macro and alias template should be in <tuple>
// but we define them here, to be available when the partial specializations
// of tuple_element<pair<T,U>> and tuple_element<array<T,N>> are defined.
#define __cpp_lib_tuple_element_t 201402L

  template<std::size_t __i, typename _Tp>
    using tuple_element_t = typename tuple_element<__i, _Tp>::type;
#endif

  // Various functions which give std::pair a tuple-like interface.

  /// Partial specialization for std::pair
  template<typename _T1, typename _T2>
    struct __is_tuple_like_impl<std::pair<_T1, _T2>> : true_type
    { };

  /// Partial specialization for std::pair
  template<class _Tp1, class _Tp2>
    struct tuple_size<std::pair<_Tp1, _Tp2>>
    : public integral_constant<std::size_t, 2> { };

  /// Partial specialization for std::pair
  template<class _Tp1, class _Tp2>
    struct tuple_element<0, std::pair<_Tp1, _Tp2>>
    { typedef _Tp1 type; };

  /// Partial specialization for std::pair
  template<class _Tp1, class _Tp2>
    struct tuple_element<1, std::pair<_Tp1, _Tp2>>
    { typedef _Tp2 type; };

  template<std::size_t _Int>
    struct __pair_get;

  template<>
    struct __pair_get<0>
    {
      template<typename _Tp1, typename _Tp2>
        static constexpr _Tp1&
        __get(std::pair<_Tp1, _Tp2>& __pair) noexcept
        { return __pair.first; }

      template<typename _Tp1, typename _Tp2>
        static constexpr _Tp1&&
        __move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept
        { return std::forward<_Tp1>(__pair.first); }

      template<typename _Tp1, typename _Tp2>
        static constexpr const _Tp1&
        __const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept
        { return __pair.first; }

      template<typename _Tp1, typename _Tp2>
        static constexpr const _Tp1&&
        __const_move_get(const std::pair<_Tp1, _Tp2>&& __pair) noexcept
        { return std::forward<const _Tp1>(__pair.first); }
    };

  template<>
    struct __pair_get<1>
    {
      template<typename _Tp1, typename _Tp2>
        static constexpr _Tp2&
        __get(std::pair<_Tp1, _Tp2>& __pair) noexcept
        { return __pair.second; }

      template<typename _Tp1, typename _Tp2>
        static constexpr _Tp2&&
        __move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept
        { return std::forward<_Tp2>(__pair.second); }

      template<typename _Tp1, typename _Tp2>
        static constexpr const _Tp2&
        __const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept
        { return __pair.second; }

      template<typename _Tp1, typename _Tp2>
        static constexpr const _Tp2&&
        __const_move_get(const std::pair<_Tp1, _Tp2>&& __pair) noexcept
        { return std::forward<const _Tp2>(__pair.second); }
    };

  template<std::size_t _Int, class _Tp1, class _Tp2>
    constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&
    get(std::pair<_Tp1, _Tp2>& __in) noexcept
    { return __pair_get<_Int>::__get(__in); }

  template<std::size_t _Int, class _Tp1, class _Tp2>
    constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&&
    get(std::pair<_Tp1, _Tp2>&& __in) noexcept
    { return __pair_get<_Int>::__move_get(std::move(__in)); }

  template<std::size_t _Int, class _Tp1, class _Tp2>
    constexpr const typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&
    get(const std::pair<_Tp1, _Tp2>& __in) noexcept
    { return __pair_get<_Int>::__const_get(__in); }

  template<std::size_t _Int, class _Tp1, class _Tp2>
    constexpr const typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&&
    get(const std::pair<_Tp1, _Tp2>&& __in) noexcept
    { return __pair_get<_Int>::__const_move_get(std::move(__in)); }

#if __cplusplus > 201103L

#define __cpp_lib_tuples_by_type 201304

  template <typename _Tp, typename _Up>
    constexpr _Tp&
    get(pair<_Tp, _Up>& __p) noexcept
    { return __p.first; }

  template <typename _Tp, typename _Up>
    constexpr const _Tp&
    get(const pair<_Tp, _Up>& __p) noexcept
    { return __p.first; }

  template <typename _Tp, typename _Up>
    constexpr _Tp&&
    get(pair<_Tp, _Up>&& __p) noexcept
    { return std::move(__p.first); }

  template <typename _Tp, typename _Up>
    constexpr const _Tp&&
    get(const pair<_Tp, _Up>&& __p) noexcept
    { return std::move(__p.first); }

  template <typename _Tp, typename _Up>
    constexpr _Tp&
    get(pair<_Up, _Tp>& __p) noexcept
    { return __p.second; }

  template <typename _Tp, typename _Up>
    constexpr const _Tp&
    get(const pair<_Up, _Tp>& __p) noexcept
    { return __p.second; }

  template <typename _Tp, typename _Up>
    constexpr _Tp&&
    get(pair<_Up, _Tp>&& __p) noexcept
    { return std::move(__p.second); }

  template <typename _Tp, typename _Up>
    constexpr const _Tp&&
    get(const pair<_Up, _Tp>&& __p) noexcept
    { return std::move(__p.second); }

#define __cpp_lib_exchange_function 201304

#if __cplusplus > 201703L
#  define __cpp_lib_constexpr_algorithms 201806L
#endif

  /// Assign @p __new_val to @p __obj and return its previous value.
  template <typename _Tp, typename _Up = _Tp>
    _GLIBCXX20_CONSTEXPR
    inline _Tp
    exchange(_Tp& __obj, _Up&& __new_val)
    { return std::__exchange(__obj, std::forward<_Up>(__new_val)); }

#endif

  // Stores a tuple of indices.  Used by tuple and pair, and by bind() to
  // extract the elements in a tuple.
  template<size_t... _Indexes> struct _Index_tuple { };

#ifdef __has_builtin
# if __has_builtin(__make_integer_seq)
#  define _GLIBCXX_USE_MAKE_INTEGER_SEQ 1
# endif
#endif

  // Builds an _Index_tuple<0, 1, 2, ..., _Num-1>.
  template<size_t _Num>
    struct _Build_index_tuple
    {
#if _GLIBCXX_USE_MAKE_INTEGER_SEQ
      template<typename, size_t... _Indices>
        using _IdxTuple = _Index_tuple<_Indices...>;

      using __type = __make_integer_seq<_IdxTuple, size_t, _Num>;
#else
      using __type = _Index_tuple<__integer_pack(_Num)...>;
#endif
    };

#if __cplusplus > 201103L

#define __cpp_lib_integer_sequence 201304

  /// Class template integer_sequence
  template<typename _Tp, _Tp... _Idx>
    struct integer_sequence
    {
      typedef _Tp value_type;
      static constexpr size_t size() noexcept { return sizeof...(_Idx); }
    };

  /// Alias template make_integer_sequence
  template<typename _Tp, _Tp _Num>
    using make_integer_sequence
#if _GLIBCXX_USE_MAKE_INTEGER_SEQ
      = __make_integer_seq<integer_sequence, _Tp, _Num>;
#else
      = integer_sequence<_Tp, __integer_pack(_Num)...>;
#endif

#undef _GLIBCXX_USE_MAKE_INTEGER_SEQ

  /// Alias template index_sequence
  template<size_t... _Idx>
    using index_sequence = integer_sequence<size_t, _Idx...>;

  /// Alias template make_index_sequence
  template<size_t _Num>
    using make_index_sequence = make_integer_sequence<size_t, _Num>;

  /// Alias template index_sequence_for
  template<typename... _Types>
    using index_sequence_for = make_index_sequence<sizeof...(_Types)>;
#endif

#if __cplusplus > 201402L

  struct in_place_t {
    explicit in_place_t() = default;
  };

  inline constexpr in_place_t in_place{};

  template<typename _Tp> struct in_place_type_t
  {
    explicit in_place_type_t() = default;
  };

  template<typename _Tp>
    inline constexpr in_place_type_t<_Tp> in_place_type{};

  template<size_t _Idx> struct in_place_index_t
  {
    explicit in_place_index_t() = default;
  };

  template<size_t _Idx>
    inline constexpr in_place_index_t<_Idx> in_place_index{};

  template<typename>
    struct __is_in_place_type_impl : false_type
    { };

  template<typename _Tp>
    struct __is_in_place_type_impl<in_place_type_t<_Tp>> : true_type
    { };

  template<typename _Tp>
    struct __is_in_place_type
      : public __is_in_place_type_impl<_Tp>
    { };

#define  __cpp_lib_as_const 201510
  template<typename _Tp>
    constexpr add_const_t<_Tp>& as_const(_Tp& __t) noexcept { return __t; }

  template<typename _Tp>
    void as_const(const _Tp&&) = delete;

#endif // C++17

_GLIBCXX_END_NAMESPACE_VERSION
} // namespace

#endif

#endif /* _GLIBCXX_UTILITY */
Commit	Line	Data
54c1bf78	1	// <utility> -- C++ --
de96ac46	2
8d9254fc	3	// Copyright (C) 2001-2020 Free Software Foundation, Inc.
de96ac46 BK	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
748086b7	8	// Free Software Foundation; either version 3, or (at your option)
de96ac46 BK	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
748086b7 JJ	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.
de96ac46	19
748086b7 JJ	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/>.
de96ac46	24
54c1bf78 BK	25	/*
	26	*
	27	* Copyright (c) 1994
	28	* Hewlett-Packard Company
	29	*
	30	* Permission to use, copy, modify, distribute and sell this software
	31	* and its documentation for any purpose is hereby granted without fee,
	32	* provided that the above copyright notice appear in all copies and
	33	* that both that copyright notice and this permission notice appear
	34	* in supporting documentation. Hewlett-Packard Company makes no
	35	* representations about the suitability of this software for any
	36	* purpose. It is provided "as is" without express or implied warranty.
	37	*
	38	*
	39	* Copyright (c) 1996,1997
	40	* Silicon Graphics Computer Systems, Inc.
	41	*
	42	* Permission to use, copy, modify, distribute and sell this software
	43	* and its documentation for any purpose is hereby granted without fee,
	44	* provided that the above copyright notice appear in all copies and
	45	* that both that copyright notice and this permission notice appear
	46	* in supporting documentation. Silicon Graphics makes no
	47	* representations about the suitability of this software for any
	48	* purpose. It is provided "as is" without express or implied warranty.
	49	*/
	50
143c27b0	51	/** @file include/utility
33ac58d5	52	* This is a Standard C++ Library header.
2f9d51b8 PE	53	*/
2f9d51b8 PE	54
1143680e SE	55	#ifndef _GLIBCXX_UTILITY
1143680e SE	56	#define _GLIBCXX_UTILITY 1
54c1bf78 BK	57
54c1bf78 BK	58	#pragma GCC system_header
285b36d6	59
8e32aa11 BK	60	/**
	61	* @defgroup utilities Utilities
	62	*
	63	* Components deemed generally useful. Includes pair, tuple,
	64	* forward/move helpers, ratio, function object, metaprogramming and
	65	* type traits, time, date, and memory functions.
	66	*/
	67
54c1bf78 BK	68	#include <bits/c++config.h>
	69	#include <bits/stl_relops.h>
	70	#include <bits/stl_pair.h>
	71
734f5023	72	#if __cplusplus >= 201103L
a15f7cb8	73
7d17de7f	74	#include <type_traits>
53dc5044 PC	75	#include <bits/move.h>
	76	#include <initializer_list>
	77
12ffa228 BK	78	namespace std _GLIBCXX_VISIBILITY(default)
	79	{
	80	_GLIBCXX_BEGIN_NAMESPACE_VERSION
53dc5044	81
de0830e1 VV	82	/// Finds the size of a given tuple type.
	83	template<typename _Tp>
	84	struct tuple_size;
	85
	86	// _GLIBCXX_RESOLVE_LIB_DEFECTS
f859f912	87	// 2313. tuple_size should always derive from integral_constant<size_t, N>
6ae2ae3b	88	// 2770. tuple_size<const T> specialization is not SFINAE compatible
6ae2ae3b	89
f859f912 JW	90	template<typename _Tp,
	91	typename _Up = typename remove_cv<_Tp>::type,
	92	typename = typename enable_if<is_same<_Tp, _Up>::value>::type,
	93	size_t = tuple_size<_Tp>::value>
	94	using __enable_if_has_tuple_size = _Tp;
de0830e1	95
6ae2ae3b	96	template<typename _Tp>
f859f912 JW	97	struct tuple_size<const __enable_if_has_tuple_size<_Tp>>
f859f912 JW	98	: public tuple_size<_Tp> { };
6ae2ae3b	99
de0830e1	100	template<typename _Tp>
f859f912 JW	101	struct tuple_size<volatile __enable_if_has_tuple_size<_Tp>>
f859f912 JW	102	: public tuple_size<_Tp> { };
de0830e1 VV	103
de0830e1 VV	104	template<typename _Tp>
f859f912 JW	105	struct tuple_size<const volatile __enable_if_has_tuple_size<_Tp>>
f859f912 JW	106	: public tuple_size<_Tp> { };
de0830e1 VV	107
	108	/// Gives the type of the ith element of a given tuple type.
	109	template<std::size_t __i, typename _Tp>
	110	struct tuple_element;
	111
	112	// Duplicate of C++14's tuple_element_t for internal use in C++11 mode
	113	template<std::size_t __i, typename _Tp>
	114	using __tuple_element_t = typename tuple_element<__i, _Tp>::type;
	115
	116	template<std::size_t __i, typename _Tp>
	117	struct tuple_element<__i, const _Tp>
	118	{
	119	typedef typename add_const<__tuple_element_t<__i, _Tp>>::type type;
	120	};
	121
	122	template<std::size_t __i, typename _Tp>
	123	struct tuple_element<__i, volatile _Tp>
	124	{
	125	typedef typename add_volatile<__tuple_element_t<__i, _Tp>>::type type;
	126	};
	127
	128	template<std::size_t __i, typename _Tp>
	129	struct tuple_element<__i, const volatile _Tp>
	130	{
	131	typedef typename add_cv<__tuple_element_t<__i, _Tp>>::type type;
	132	};
	133
2d26d4ce JW	134	#if __cplusplus >= 201402L
	135	// The standard says this macro and alias template should be in <tuple>
	136	// but we define them here, to be available when the partial specializations
	137	// of tuple_element<pair<T,U>> and tuple_element<array<T,N>> are defined.
	138	#define __cpp_lib_tuple_element_t 201402L
	139
	140	template<std::size_t __i, typename _Tp>
	141	using tuple_element_t = typename tuple_element<__i, _Tp>::type;
	142	#endif
	143
7d17de7f FD	144	// Various functions which give std::pair a tuple-like interface.
	145
	146	/// Partial specialization for std::pair
	147	template<typename _T1, typename _T2>
	148	struct __is_tuple_like_impl<std::pair<_T1, _T2>> : true_type
	149	{ };
3a004764 JW	150
3a004764 JW	151	/// Partial specialization for std::pair
53dc5044	152	template<class _Tp1, class _Tp2>
7933dc2a	153	struct tuple_size<std::pair<_Tp1, _Tp2>>
664e12c1	154	: public integral_constant<std::size_t, 2> { };
53dc5044	155
3a004764	156	/// Partial specialization for std::pair
53dc5044	157	template<class _Tp1, class _Tp2>
7933dc2a	158	struct tuple_element<0, std::pair<_Tp1, _Tp2>>
53dc5044	159	{ typedef _Tp1 type; };
33ac58d5	160
3a004764	161	/// Partial specialization for std::pair
53dc5044	162	template<class _Tp1, class _Tp2>
7933dc2a	163	struct tuple_element<1, std::pair<_Tp1, _Tp2>>
53dc5044 PC	164	{ typedef _Tp2 type; };
	165
	166	template<std::size_t _Int>
	167	struct __pair_get;
	168
	169	template<>
	170	struct __pair_get<0>
	171	{
	172	template<typename _Tp1, typename _Tp2>
9480716c	173	static constexpr _Tp1&
7933dc2a	174	__get(std::pair<_Tp1, _Tp2>& __pair) noexcept
18eeaec4 PC	175	{ return __pair.first; }
18eeaec4 PC	176
18eeaec4	177	template<typename _Tp1, typename _Tp2>
9480716c	178	static constexpr _Tp1&&
18eeaec4 PC	179	__move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept
18eeaec4 PC	180	{ return std::forward<_Tp1>(__pair.first); }
53dc5044 PC	181
53dc5044 PC	182	template<typename _Tp1, typename _Tp2>
9480716c	183	static constexpr const _Tp1&
7933dc2a	184	__const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept
18eeaec4	185	{ return __pair.first; }
ccbbf8df VV	186
	187	template<typename _Tp1, typename _Tp2>
	188	static constexpr const _Tp1&&
	189	__const_move_get(const std::pair<_Tp1, _Tp2>&& __pair) noexcept
	190	{ return std::forward<const _Tp1>(__pair.first); }
53dc5044 PC	191	};
	192
	193	template<>
	194	struct __pair_get<1>
	195	{
	196	template<typename _Tp1, typename _Tp2>
9480716c	197	static constexpr _Tp2&
7933dc2a	198	__get(std::pair<_Tp1, _Tp2>& __pair) noexcept
18eeaec4 PC	199	{ return __pair.second; }
18eeaec4 PC	200
18eeaec4	201	template<typename _Tp1, typename _Tp2>
9480716c	202	static constexpr _Tp2&&
18eeaec4 PC	203	__move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept
18eeaec4 PC	204	{ return std::forward<_Tp2>(__pair.second); }
53dc5044 PC	205
53dc5044 PC	206	template<typename _Tp1, typename _Tp2>
9480716c	207	static constexpr const _Tp2&
7933dc2a	208	__const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept
18eeaec4	209	{ return __pair.second; }
ccbbf8df VV	210
	211	template<typename _Tp1, typename _Tp2>
	212	static constexpr const _Tp2&&
	213	__const_move_get(const std::pair<_Tp1, _Tp2>&& __pair) noexcept
	214	{ return std::forward<const _Tp2>(__pair.second); }
53dc5044 PC	215	};
	216
	217	template<std::size_t _Int, class _Tp1, class _Tp2>
9480716c	218	constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&
7933dc2a	219	get(std::pair<_Tp1, _Tp2>& __in) noexcept
53dc5044 PC	220	{ return __pair_get<_Int>::__get(__in); }
53dc5044 PC	221
18eeaec4	222	template<std::size_t _Int, class _Tp1, class _Tp2>
9480716c	223	constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&&
18eeaec4 PC	224	get(std::pair<_Tp1, _Tp2>&& __in) noexcept
18eeaec4 PC	225	{ return __pair_get<_Int>::__move_get(std::move(__in)); }
18eeaec4	226
53dc5044	227	template<std::size_t _Int, class _Tp1, class _Tp2>
9480716c	228	constexpr const typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&
7933dc2a	229	get(const std::pair<_Tp1, _Tp2>& __in) noexcept
53dc5044 PC	230	{ return __pair_get<_Int>::__const_get(__in); }
53dc5044 PC	231
ccbbf8df VV	232	template<std::size_t _Int, class _Tp1, class _Tp2>
	233	constexpr const typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&&
	234	get(const std::pair<_Tp1, _Tp2>&& __in) noexcept
	235	{ return __pair_get<_Int>::__const_move_get(std::move(__in)); }
	236
c98b0598	237	#if __cplusplus > 201103L
a15f7cb8 ESR	238
	239	#define __cpp_lib_tuples_by_type 201304
	240
b5a8fed6 JW	241	template <typename _Tp, typename _Up>
	242	constexpr _Tp&
	243	get(pair<_Tp, _Up>& __p) noexcept
	244	{ return __p.first; }
	245
	246	template <typename _Tp, typename _Up>
	247	constexpr const _Tp&
	248	get(const pair<_Tp, _Up>& __p) noexcept
	249	{ return __p.first; }
	250
	251	template <typename _Tp, typename _Up>
	252	constexpr _Tp&&
	253	get(pair<_Tp, _Up>&& __p) noexcept
	254	{ return std::move(__p.first); }
	255
ccbbf8df VV	256	template <typename _Tp, typename _Up>
	257	constexpr const _Tp&&
	258	get(const pair<_Tp, _Up>&& __p) noexcept
	259	{ return std::move(__p.first); }
	260
b5a8fed6 JW	261	template <typename _Tp, typename _Up>
	262	constexpr _Tp&
	263	get(pair<_Up, _Tp>& __p) noexcept
	264	{ return __p.second; }
	265
	266	template <typename _Tp, typename _Up>
	267	constexpr const _Tp&
	268	get(const pair<_Up, _Tp>& __p) noexcept
	269	{ return __p.second; }
	270
	271	template <typename _Tp, typename _Up>
	272	constexpr _Tp&&
	273	get(pair<_Up, _Tp>&& __p) noexcept
	274	{ return std::move(__p.second); }
	275
ccbbf8df VV	276	template <typename _Tp, typename _Up>
	277	constexpr const _Tp&&
	278	get(const pair<_Up, _Tp>&& __p) noexcept
	279	{ return std::move(__p.second); }
	280
a15f7cb8 ESR	281	#define __cpp_lib_exchange_function 201304
a15f7cb8 ESR	282
3a66e68a	283	#if __cplusplus > 201703L
b30ee71a	284	# define __cpp_lib_constexpr_algorithms 201806L
3a66e68a ESR	285	#endif
3a66e68a ESR	286
c98b0598	287	/// Assign @p __new_val to @p __obj and return its previous value.
b5a8fed6	288	template <typename _Tp, typename _Up = _Tp>
3a66e68a	289	_GLIBCXX20_CONSTEXPR
c98b0598 JW	290	inline _Tp
c98b0598 JW	291	exchange(_Tp& __obj, _Up&& __new_val)
9b817548	292	{ return std::__exchange(__obj, std::forward<_Up>(__new_val)); }
3a66e68a	293
c98b0598 JW	294	#endif
c98b0598 JW	295
1b1bdc03 JW	296	// Stores a tuple of indices. Used by tuple and pair, and by bind() to
1b1bdc03 JW	297	// extract the elements in a tuple.
5f0b7c95 JW	298	template<size_t... _Indexes> struct _Index_tuple { };
5f0b7c95 JW	299
db624b3b JW	300	#ifdef __has_builtin
	301	# if __has_builtin(__make_integer_seq)
	302	# define _GLIBCXX_USE_MAKE_INTEGER_SEQ 1
	303	# endif
	304	#endif
1b1bdc03 JW	305
	306	// Builds an _Index_tuple<0, 1, 2, ..., _Num-1>.
	307	template<size_t _Num>
	308	struct _Build_index_tuple
	309	{
db624b3b JW	310	#if _GLIBCXX_USE_MAKE_INTEGER_SEQ
	311	template<typename, size_t... _Indices>
	312	using _IdxTuple = _Index_tuple<_Indices...>;
1b1bdc03	313
db624b3b JW	314	using __type = __make_integer_seq<_IdxTuple, size_t, _Num>;
	315	#else
	316	using __type = _Index_tuple<__integer_pack(_Num)...>;
	317	#endif
1b1bdc03 JW	318	};
	319
	320	#if __cplusplus > 201103L
a15f7cb8 ESR	321
	322	#define __cpp_lib_integer_sequence 201304
	323
1b1bdc03 JW	324	/// Class template integer_sequence
	325	template<typename _Tp, _Tp... _Idx>
	326	struct integer_sequence
	327	{
	328	typedef _Tp value_type;
352111c5	329	static constexpr size_t size() noexcept { return sizeof...(_Idx); }
1b1bdc03 JW	330	};
1b1bdc03 JW	331
1b1bdc03 JW	332	/// Alias template make_integer_sequence
	333	template<typename _Tp, _Tp _Num>
	334	using make_integer_sequence
db624b3b JW	335	#if _GLIBCXX_USE_MAKE_INTEGER_SEQ
	336	= __make_integer_seq<integer_sequence, _Tp, _Num>;
	337	#else
	338	= integer_sequence<_Tp, __integer_pack(_Num)...>;
	339	#endif
	340
	341	#undef _GLIBCXX_USE_MAKE_INTEGER_SEQ
1b1bdc03 JW	342
	343	/// Alias template index_sequence
	344	template<size_t... _Idx>
	345	using index_sequence = integer_sequence<size_t, _Idx...>;
	346
	347	/// Alias template make_index_sequence
	348	template<size_t _Num>
	349	using make_index_sequence = make_integer_sequence<size_t, _Num>;
	350
	351	/// Alias template index_sequence_for
	352	template<typename... _Types>
	353	using index_sequence_for = make_index_sequence<sizeof...(_Types)>;
	354	#endif
	355
25a69162 VV	356	#if __cplusplus > 201402L
25a69162 VV	357
627a2f59 VV	358	struct in_place_t {
627a2f59 VV	359	explicit in_place_t() = default;
25a69162 VV	360	};
25a69162 VV	361
627a2f59 VV	362	inline constexpr in_place_t in_place{};
	363
	364	template<typename _Tp> struct in_place_type_t
	365	{
	366	explicit in_place_type_t() = default;
	367	};
	368
	369	template<typename _Tp>
	370	inline constexpr in_place_type_t<_Tp> in_place_type{};
	371
	372	template<size_t _Idx> struct in_place_index_t
	373	{
	374	explicit in_place_index_t() = default;
	375	};
	376
	377	template<size_t _Idx>
	378	inline constexpr in_place_index_t<_Idx> in_place_index{};
25a69162	379
5c578ae4 VV	380	template<typename>
	381	struct __is_in_place_type_impl : false_type
	382	{ };
	383
	384	template<typename _Tp>
	385	struct __is_in_place_type_impl<in_place_type_t<_Tp>> : true_type
	386	{ };
	387
	388	template<typename _Tp>
	389	struct __is_in_place_type
	390	: public __is_in_place_type_impl<_Tp>
	391	{ };
	392
32eaac9c JW	393	#define __cpp_lib_as_const 201510
	394	template<typename _Tp>
	395	constexpr add_const_t<_Tp>& as_const(_Tp& __t) noexcept { return __t; }
	396
	397	template<typename _Tp>
	398	void as_const(const _Tp&&) = delete;
	399
5c578ae4	400	#endif // C++17
25a69162	401
12ffa228 BK	402	_GLIBCXX_END_NAMESPACE_VERSION
12ffa228 BK	403	} // namespace
53dc5044	404
af13a7a6 BK	405	#endif
af13a7a6 BK	406
1143680e	407	#endif /* _GLIBCXX_UTILITY */