utility
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// <utility> -*- C++ -*-
// Copyright (C) 2001-2018 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>
#if __cplusplus > 201402L
#include <exception>
#endif
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 > 201103L
#define __cpp_lib_tuple_element_t 201402
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 */
move.h
std::tuple_element
tuple_element
Definition: array:359
std::experimental::fundamentals_v1::in_place
constexpr in_place_t in_place
Tag for in-place construction.
Definition: optional:88
c++config.h
std::add_const_t
typename add_const< _Tp >::type add_const_t
Alias template for add_const.
Definition: type_traits:1449
std::exchange
_Tp exchange(_Tp &__obj, _Up &&__new_val)
Assign __new_val to __obj and return its previous value.
Definition: utility:287
std::pair::second
_T2 second
first is a copy of the first object
Definition: stl_pair.h:204
type_traits
std::integer_sequence
Class template integer_sequence.
Definition: utility:321
std::pair::first
_T1 first
second_type is the second bound type
Definition: stl_pair.h:203
std::tuple_size
tuple_size
Definition: array:350
exception
initializer_list
stl_relops.h
std
ISO C++ entities toplevel namespace is std.
std::integral_constant
integral_constant
Definition: type_traits:69
stl_pair.h
std::pair
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:198