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

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

// Copyright (C) 2001-2019 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

  /// Assign @p __new_val to @p __obj and return its previous value.
  template <typename _Tp, typename _Up = _Tp>
    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
e1e0016d	1	// <utility> -- C++ --
01dd2c6c	2
fbd26352	3	// Copyright (C) 2001-2019 Free Software Foundation, Inc.
01dd2c6c	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
6bc9506f	8	// Free Software Foundation; either version 3, or (at your option)
01dd2c6c	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
6bc9506f	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.
01dd2c6c	19
6bc9506f	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/>.
01dd2c6c	24
e1e0016d	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
944beac5	51	/** @file include/utility
fb809cfc	52	* This is a Standard C++ Library header.
78ee80ac	53	*/
78ee80ac	54
a438d9ac	55	#ifndef _GLIBCXX_UTILITY
a438d9ac	56	#define _GLIBCXX_UTILITY 1
e1e0016d	57
e1e0016d	58	#pragma GCC system_header
d570f2e9	59
73337dee	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
e1e0016d	68	#include <bits/c++config.h>
	69	#include <bits/stl_relops.h>
	70	#include <bits/stl_pair.h>
	71
0c8766b1	72	#if __cplusplus >= 201103L
f6751ff2	73
a1d0f6e1	74	#include <type_traits>
5022cf3f	75	#include <bits/move.h>
	76	#include <initializer_list>
	77
2948dd21	78	namespace std _GLIBCXX_VISIBILITY(default)
	79	{
	80	_GLIBCXX_BEGIN_NAMESPACE_VERSION
5022cf3f	81
1db1b56c	82	/// Finds the size of a given tuple type.
	83	template<typename _Tp>
	84	struct tuple_size;
	85
	86	// _GLIBCXX_RESOLVE_LIB_DEFECTS
d791a23a	87	// 2313. tuple_size should always derive from integral_constant<size_t, N>
22d87db6	88	// 2770. tuple_size<const T> specialization is not SFINAE compatible
22d87db6	89
d791a23a	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;
1db1b56c	95
22d87db6	96	template<typename _Tp>
d791a23a	97	struct tuple_size<const __enable_if_has_tuple_size<_Tp>>
d791a23a	98	: public tuple_size<_Tp> { };
22d87db6	99
1db1b56c	100	template<typename _Tp>
d791a23a	101	struct tuple_size<volatile __enable_if_has_tuple_size<_Tp>>
d791a23a	102	: public tuple_size<_Tp> { };
1db1b56c	103
1db1b56c	104	template<typename _Tp>
d791a23a	105	struct tuple_size<const volatile __enable_if_has_tuple_size<_Tp>>
d791a23a	106	: public tuple_size<_Tp> { };
1db1b56c	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
80bdf09d	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
a1d0f6e1	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	{ };
3825cab1	150
3825cab1	151	/// Partial specialization for std::pair
5022cf3f	152	template<class _Tp1, class _Tp2>
2781800c	153	struct tuple_size<std::pair<_Tp1, _Tp2>>
46262525	154	: public integral_constant<std::size_t, 2> { };
5022cf3f	155
3825cab1	156	/// Partial specialization for std::pair
5022cf3f	157	template<class _Tp1, class _Tp2>
2781800c	158	struct tuple_element<0, std::pair<_Tp1, _Tp2>>
5022cf3f	159	{ typedef _Tp1 type; };
fb809cfc	160
3825cab1	161	/// Partial specialization for std::pair
5022cf3f	162	template<class _Tp1, class _Tp2>
2781800c	163	struct tuple_element<1, std::pair<_Tp1, _Tp2>>
5022cf3f	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>
f749333e	173	static constexpr _Tp1&
2781800c	174	__get(std::pair<_Tp1, _Tp2>& __pair) noexcept
cb17d4f2	175	{ return __pair.first; }
cb17d4f2	176
cb17d4f2	177	template<typename _Tp1, typename _Tp2>
f749333e	178	static constexpr _Tp1&&
cb17d4f2	179	__move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept
cb17d4f2	180	{ return std::forward<_Tp1>(__pair.first); }
5022cf3f	181
5022cf3f	182	template<typename _Tp1, typename _Tp2>
f749333e	183	static constexpr const _Tp1&
2781800c	184	__const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept
cb17d4f2	185	{ return __pair.first; }
6d8efcd4	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); }
5022cf3f	191	};
	192
	193	template<>
	194	struct __pair_get<1>
	195	{
	196	template<typename _Tp1, typename _Tp2>
f749333e	197	static constexpr _Tp2&
2781800c	198	__get(std::pair<_Tp1, _Tp2>& __pair) noexcept
cb17d4f2	199	{ return __pair.second; }
cb17d4f2	200
cb17d4f2	201	template<typename _Tp1, typename _Tp2>
f749333e	202	static constexpr _Tp2&&
cb17d4f2	203	__move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept
cb17d4f2	204	{ return std::forward<_Tp2>(__pair.second); }
5022cf3f	205
5022cf3f	206	template<typename _Tp1, typename _Tp2>
f749333e	207	static constexpr const _Tp2&
2781800c	208	__const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept
cb17d4f2	209	{ return __pair.second; }
6d8efcd4	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); }
5022cf3f	215	};
	216
	217	template<std::size_t _Int, class _Tp1, class _Tp2>
f749333e	218	constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&
2781800c	219	get(std::pair<_Tp1, _Tp2>& __in) noexcept
5022cf3f	220	{ return __pair_get<_Int>::__get(__in); }
5022cf3f	221
cb17d4f2	222	template<std::size_t _Int, class _Tp1, class _Tp2>
f749333e	223	constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&&
cb17d4f2	224	get(std::pair<_Tp1, _Tp2>&& __in) noexcept
cb17d4f2	225	{ return __pair_get<_Int>::__move_get(std::move(__in)); }
cb17d4f2	226
5022cf3f	227	template<std::size_t _Int, class _Tp1, class _Tp2>
f749333e	228	constexpr const typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&
2781800c	229	get(const std::pair<_Tp1, _Tp2>& __in) noexcept
5022cf3f	230	{ return __pair_get<_Int>::__const_get(__in); }
5022cf3f	231
6d8efcd4	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
c8ae75b7	237	#if __cplusplus > 201103L
f6751ff2	238
	239	#define __cpp_lib_tuples_by_type 201304
	240
2185f051	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
6d8efcd4	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
2185f051	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
6d8efcd4	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
f6751ff2	281	#define __cpp_lib_exchange_function 201304
f6751ff2	282
c8ae75b7	283	/// Assign @p __new_val to @p __obj and return its previous value.
2185f051	284	template <typename _Tp, typename _Up = _Tp>
c8ae75b7	285	inline _Tp
c8ae75b7	286	exchange(_Tp& __obj, _Up&& __new_val)
28f8cba2	287	{ return std::__exchange(__obj, std::forward<_Up>(__new_val)); }
c8ae75b7	288	#endif
c8ae75b7	289
d7c3eac6	290	// Stores a tuple of indices. Used by tuple and pair, and by bind() to
d7c3eac6	291	// extract the elements in a tuple.
d8e55bb1	292	template<size_t... _Indexes> struct _Index_tuple { };
d8e55bb1	293
f78676f0	294	#ifdef __has_builtin
	295	# if __has_builtin(__make_integer_seq)
	296	# define _GLIBCXX_USE_MAKE_INTEGER_SEQ 1
	297	# endif
	298	#endif
d7c3eac6	299
	300	// Builds an _Index_tuple<0, 1, 2, ..., _Num-1>.
	301	template<size_t _Num>
	302	struct _Build_index_tuple
	303	{
f78676f0	304	#if _GLIBCXX_USE_MAKE_INTEGER_SEQ
	305	template<typename, size_t... _Indices>
	306	using _IdxTuple = _Index_tuple<_Indices...>;
d7c3eac6	307
f78676f0	308	using __type = __make_integer_seq<_IdxTuple, size_t, _Num>;
	309	#else
	310	using __type = _Index_tuple<__integer_pack(_Num)...>;
	311	#endif
d7c3eac6	312	};
	313
	314	#if __cplusplus > 201103L
f6751ff2	315
	316	#define __cpp_lib_integer_sequence 201304
	317
d7c3eac6	318	/// Class template integer_sequence
	319	template<typename _Tp, _Tp... _Idx>
	320	struct integer_sequence
	321	{
	322	typedef _Tp value_type;
962c2793	323	static constexpr size_t size() noexcept { return sizeof...(_Idx); }
d7c3eac6	324	};
d7c3eac6	325
d7c3eac6	326	/// Alias template make_integer_sequence
	327	template<typename _Tp, _Tp _Num>
	328	using make_integer_sequence
f78676f0	329	#if _GLIBCXX_USE_MAKE_INTEGER_SEQ
	330	= __make_integer_seq<integer_sequence, _Tp, _Num>;
	331	#else
	332	= integer_sequence<_Tp, __integer_pack(_Num)...>;
	333	#endif
	334
	335	#undef _GLIBCXX_USE_MAKE_INTEGER_SEQ
d7c3eac6	336
	337	/// Alias template index_sequence
	338	template<size_t... _Idx>
	339	using index_sequence = integer_sequence<size_t, _Idx...>;
	340
	341	/// Alias template make_index_sequence
	342	template<size_t _Num>
	343	using make_index_sequence = make_integer_sequence<size_t, _Num>;
	344
	345	/// Alias template index_sequence_for
	346	template<typename... _Types>
	347	using index_sequence_for = make_index_sequence<sizeof...(_Types)>;
	348	#endif
	349
1a669380	350	#if __cplusplus > 201402L
1a669380	351
ee6c971a	352	struct in_place_t {
ee6c971a	353	explicit in_place_t() = default;
1a669380	354	};
1a669380	355
ee6c971a	356	inline constexpr in_place_t in_place{};
	357
	358	template<typename _Tp> struct in_place_type_t
	359	{
	360	explicit in_place_type_t() = default;
	361	};
	362
	363	template<typename _Tp>
	364	inline constexpr in_place_type_t<_Tp> in_place_type{};
	365
	366	template<size_t _Idx> struct in_place_index_t
	367	{
	368	explicit in_place_index_t() = default;
	369	};
	370
	371	template<size_t _Idx>
	372	inline constexpr in_place_index_t<_Idx> in_place_index{};
1a669380	373
4e2d3fab	374	template<typename>
	375	struct __is_in_place_type_impl : false_type
	376	{ };
	377
	378	template<typename _Tp>
	379	struct __is_in_place_type_impl<in_place_type_t<_Tp>> : true_type
	380	{ };
	381
	382	template<typename _Tp>
	383	struct __is_in_place_type
	384	: public __is_in_place_type_impl<_Tp>
	385	{ };
	386
f5f4272e	387	#define __cpp_lib_as_const 201510
	388	template<typename _Tp>
	389	constexpr add_const_t<_Tp>& as_const(_Tp& __t) noexcept { return __t; }
	390
	391	template<typename _Tp>
	392	void as_const(const _Tp&&) = delete;
	393
4e2d3fab	394	#endif // C++17
1a669380	395
2948dd21	396	_GLIBCXX_END_NAMESPACE_VERSION
2948dd21	397	} // namespace
5022cf3f	398
bec9a462	399	#endif
bec9a462	400
a438d9ac	401	#endif /* _GLIBCXX_UTILITY */