utility
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// <utility> -*- C++ -*-
// Copyright (C) 2001-2014 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 <bits/move.h>
#include <initializer_list>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
template<class _Tp>
class tuple_size;
template<std::size_t _Int, class _Tp>
class tuple_element;
// Various functions which give std::pair a tuple-like interface.
template<class _Tp1, class _Tp2>
struct tuple_size<std::pair<_Tp1, _Tp2>>
: public integral_constant<std::size_t, 2> { };
template<class _Tp1, class _Tp2>
struct tuple_element<0, std::pair<_Tp1, _Tp2>>
{ typedef _Tp1 type; };
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<>
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<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); }
#if __cplusplus > 201103L
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 _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); }
/// 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)
{
_Tp __old_val = std::move(__obj);
__obj = std::forward<_Up>(__new_val);
return __old_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
{
typedef _Index_tuple<_Indexes..., sizeof...(_Indexes)> __next;
};
// Builds an _Index_tuple<0, 1, 2, ..., _Num-1>.
template<size_t _Num>
struct _Build_index_tuple
{
typedef typename _Build_index_tuple<_Num - 1>::__type::__next __type;
};
template<>
struct _Build_index_tuple<0>
{
typedef _Index_tuple<> __type;
};
#if __cplusplus > 201103L
/// Class template integer_sequence
template<typename _Tp, _Tp... _Idx>
struct integer_sequence
{
typedef _Tp value_type;
static constexpr size_t size() { return sizeof...(_Idx); }
};
template<typename _Tp, _Tp _Num,
typename _ISeq = typename _Build_index_tuple<_Num>::__type>
struct _Make_integer_sequence;
template<typename _Tp, _Tp _Num, size_t... _Idx>
struct _Make_integer_sequence<_Tp, _Num, _Index_tuple<_Idx...>>
{
static_assert( _Num >= 0,
"Cannot make integer sequence of negative length" );
typedef integer_sequence<_Tp, static_cast<_Tp>(_Idx)...> __type;
};
/// Alias template make_integer_sequence
template<typename _Tp, _Tp _Num>
using make_integer_sequence
= typename _Make_integer_sequence<_Tp, _Num>::__type;
/// 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
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#endif
#endif /* _GLIBCXX_UTILITY */
stl_relops.h
std::pair
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:96
c++config.h
move.h
initializer_list
stl_pair.h
std::size
constexpr size_t size() const noexcept
Returns the total number of bits.
Definition: bitset:1293