You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
587 lines
20 KiB
587 lines
20 KiB
// Pair implementation -*- C++ -*-
|
|
|
|
// Copyright (C) 2001-2021 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 bits/stl_pair.h
|
|
* This is an internal header file, included by other library headers.
|
|
* Do not attempt to use it directly. @headername{utility}
|
|
*/
|
|
|
|
#ifndef _STL_PAIR_H
|
|
#define _STL_PAIR_H 1
|
|
|
|
#include <bits/move.h> // for std::move / std::forward, and std::swap
|
|
|
|
#if __cplusplus >= 201103L
|
|
# include <type_traits> // for std::__decay_and_strip, std::is_reference_v
|
|
#endif
|
|
#if __cplusplus > 201703L
|
|
# include <compare>
|
|
# define __cpp_lib_constexpr_utility 201811L
|
|
#endif
|
|
|
|
namespace std _GLIBCXX_VISIBILITY(default)
|
|
{
|
|
_GLIBCXX_BEGIN_NAMESPACE_VERSION
|
|
|
|
/**
|
|
* @addtogroup utilities
|
|
* @{
|
|
*/
|
|
|
|
#if __cplusplus >= 201103L
|
|
/// Tag type for piecewise construction of std::pair objects.
|
|
struct piecewise_construct_t { explicit piecewise_construct_t() = default; };
|
|
|
|
/// Tag for piecewise construction of std::pair objects.
|
|
_GLIBCXX17_INLINE constexpr piecewise_construct_t piecewise_construct =
|
|
piecewise_construct_t();
|
|
|
|
/// @cond undocumented
|
|
|
|
// Forward declarations.
|
|
template<typename...>
|
|
class tuple;
|
|
|
|
template<size_t...>
|
|
struct _Index_tuple;
|
|
|
|
// Concept utility functions, reused in conditionally-explicit
|
|
// constructors.
|
|
// See PR 70437, don't look at is_constructible or
|
|
// is_convertible if the types are the same to
|
|
// avoid querying those properties for incomplete types.
|
|
template <bool, typename _T1, typename _T2>
|
|
struct _PCC
|
|
{
|
|
template <typename _U1, typename _U2>
|
|
static constexpr bool _ConstructiblePair()
|
|
{
|
|
return __and_<is_constructible<_T1, const _U1&>,
|
|
is_constructible<_T2, const _U2&>>::value;
|
|
}
|
|
|
|
template <typename _U1, typename _U2>
|
|
static constexpr bool _ImplicitlyConvertiblePair()
|
|
{
|
|
return __and_<is_convertible<const _U1&, _T1>,
|
|
is_convertible<const _U2&, _T2>>::value;
|
|
}
|
|
|
|
template <typename _U1, typename _U2>
|
|
static constexpr bool _MoveConstructiblePair()
|
|
{
|
|
return __and_<is_constructible<_T1, _U1&&>,
|
|
is_constructible<_T2, _U2&&>>::value;
|
|
}
|
|
|
|
template <typename _U1, typename _U2>
|
|
static constexpr bool _ImplicitlyMoveConvertiblePair()
|
|
{
|
|
return __and_<is_convertible<_U1&&, _T1>,
|
|
is_convertible<_U2&&, _T2>>::value;
|
|
}
|
|
|
|
template <bool __implicit, typename _U1, typename _U2>
|
|
static constexpr bool _CopyMovePair()
|
|
{
|
|
using __do_converts = __and_<is_convertible<const _U1&, _T1>,
|
|
is_convertible<_U2&&, _T2>>;
|
|
using __converts = typename conditional<__implicit,
|
|
__do_converts,
|
|
__not_<__do_converts>>::type;
|
|
return __and_<is_constructible<_T1, const _U1&>,
|
|
is_constructible<_T2, _U2&&>,
|
|
__converts
|
|
>::value;
|
|
}
|
|
|
|
template <bool __implicit, typename _U1, typename _U2>
|
|
static constexpr bool _MoveCopyPair()
|
|
{
|
|
using __do_converts = __and_<is_convertible<_U1&&, _T1>,
|
|
is_convertible<const _U2&, _T2>>;
|
|
using __converts = typename conditional<__implicit,
|
|
__do_converts,
|
|
__not_<__do_converts>>::type;
|
|
return __and_<is_constructible<_T1, _U1&&>,
|
|
is_constructible<_T2, const _U2&&>,
|
|
__converts
|
|
>::value;
|
|
}
|
|
};
|
|
|
|
template <typename _T1, typename _T2>
|
|
struct _PCC<false, _T1, _T2>
|
|
{
|
|
template <typename _U1, typename _U2>
|
|
static constexpr bool _ConstructiblePair()
|
|
{
|
|
return false;
|
|
}
|
|
|
|
template <typename _U1, typename _U2>
|
|
static constexpr bool _ImplicitlyConvertiblePair()
|
|
{
|
|
return false;
|
|
}
|
|
|
|
template <typename _U1, typename _U2>
|
|
static constexpr bool _MoveConstructiblePair()
|
|
{
|
|
return false;
|
|
}
|
|
|
|
template <typename _U1, typename _U2>
|
|
static constexpr bool _ImplicitlyMoveConvertiblePair()
|
|
{
|
|
return false;
|
|
}
|
|
};
|
|
#endif // C++11
|
|
|
|
template<typename _U1, typename _U2> class __pair_base
|
|
{
|
|
#if __cplusplus >= 201103L
|
|
template<typename _T1, typename _T2> friend struct pair;
|
|
__pair_base() = default;
|
|
~__pair_base() = default;
|
|
__pair_base(const __pair_base&) = default;
|
|
__pair_base& operator=(const __pair_base&) = delete;
|
|
#endif // C++11
|
|
};
|
|
|
|
/// @endcond
|
|
|
|
/**
|
|
* @brief Struct holding two objects of arbitrary type.
|
|
*
|
|
* @tparam _T1 Type of first object.
|
|
* @tparam _T2 Type of second object.
|
|
*
|
|
* <https://gcc.gnu.org/onlinedocs/libstdc++/manual/utilities.html>
|
|
*/
|
|
template<typename _T1, typename _T2>
|
|
struct pair
|
|
: private __pair_base<_T1, _T2>
|
|
{
|
|
typedef _T1 first_type; ///< The type of the `first` member
|
|
typedef _T2 second_type; ///< The type of the `second` member
|
|
|
|
_T1 first; ///< The first member
|
|
_T2 second; ///< The second member
|
|
|
|
// _GLIBCXX_RESOLVE_LIB_DEFECTS
|
|
// 265. std::pair::pair() effects overly restrictive
|
|
/** The default constructor creates @c first and @c second using their
|
|
* respective default constructors. */
|
|
#if __cplusplus >= 201103L
|
|
template <typename _U1 = _T1,
|
|
typename _U2 = _T2,
|
|
typename enable_if<__and_<
|
|
__is_implicitly_default_constructible<_U1>,
|
|
__is_implicitly_default_constructible<_U2>>
|
|
::value, bool>::type = true>
|
|
#endif
|
|
_GLIBCXX_CONSTEXPR pair()
|
|
: first(), second() { }
|
|
|
|
#if __cplusplus >= 201103L
|
|
template <typename _U1 = _T1,
|
|
typename _U2 = _T2,
|
|
typename enable_if<__and_<
|
|
is_default_constructible<_U1>,
|
|
is_default_constructible<_U2>,
|
|
__not_<
|
|
__and_<__is_implicitly_default_constructible<_U1>,
|
|
__is_implicitly_default_constructible<_U2>>>>
|
|
::value, bool>::type = false>
|
|
explicit constexpr pair()
|
|
: first(), second() { }
|
|
#endif
|
|
|
|
#if __cplusplus < 201103L
|
|
/// Two objects may be passed to a @c pair constructor to be copied.
|
|
pair(const _T1& __a, const _T2& __b)
|
|
: first(__a), second(__b) { }
|
|
#else
|
|
// Shortcut for constraining the templates that don't take pairs.
|
|
/// @cond undocumented
|
|
using _PCCP = _PCC<true, _T1, _T2>;
|
|
/// @endcond
|
|
|
|
/// Construct from two const lvalues, allowing implicit conversions.
|
|
template<typename _U1 = _T1, typename _U2=_T2, typename
|
|
enable_if<_PCCP::template
|
|
_ConstructiblePair<_U1, _U2>()
|
|
&& _PCCP::template
|
|
_ImplicitlyConvertiblePair<_U1, _U2>(),
|
|
bool>::type=true>
|
|
constexpr pair(const _T1& __a, const _T2& __b)
|
|
: first(__a), second(__b) { }
|
|
|
|
/// Construct from two const lvalues, disallowing implicit conversions.
|
|
template<typename _U1 = _T1, typename _U2=_T2, typename
|
|
enable_if<_PCCP::template
|
|
_ConstructiblePair<_U1, _U2>()
|
|
&& !_PCCP::template
|
|
_ImplicitlyConvertiblePair<_U1, _U2>(),
|
|
bool>::type=false>
|
|
explicit constexpr pair(const _T1& __a, const _T2& __b)
|
|
: first(__a), second(__b) { }
|
|
#endif
|
|
|
|
#if __cplusplus < 201103L
|
|
/// There is also a templated constructor to convert from other pairs.
|
|
template<typename _U1, typename _U2>
|
|
pair(const pair<_U1, _U2>& __p)
|
|
: first(__p.first), second(__p.second) { }
|
|
#else
|
|
// Shortcut for constraining the templates that take pairs.
|
|
/// @cond undocumented
|
|
template <typename _U1, typename _U2>
|
|
using _PCCFP = _PCC<!is_same<_T1, _U1>::value
|
|
|| !is_same<_T2, _U2>::value,
|
|
_T1, _T2>;
|
|
/// @endcond
|
|
|
|
template<typename _U1, typename _U2, typename
|
|
enable_if<_PCCFP<_U1, _U2>::template
|
|
_ConstructiblePair<_U1, _U2>()
|
|
&& _PCCFP<_U1, _U2>::template
|
|
_ImplicitlyConvertiblePair<_U1, _U2>(),
|
|
bool>::type=true>
|
|
constexpr pair(const pair<_U1, _U2>& __p)
|
|
: first(__p.first), second(__p.second) { }
|
|
|
|
template<typename _U1, typename _U2, typename
|
|
enable_if<_PCCFP<_U1, _U2>::template
|
|
_ConstructiblePair<_U1, _U2>()
|
|
&& !_PCCFP<_U1, _U2>::template
|
|
_ImplicitlyConvertiblePair<_U1, _U2>(),
|
|
bool>::type=false>
|
|
explicit constexpr pair(const pair<_U1, _U2>& __p)
|
|
: first(__p.first), second(__p.second) { }
|
|
#endif
|
|
|
|
#if __cplusplus >= 201103L
|
|
constexpr pair(const pair&) = default; ///< Copy constructor
|
|
constexpr pair(pair&&) = default; ///< Move constructor
|
|
|
|
// DR 811.
|
|
template<typename _U1, typename
|
|
enable_if<_PCCP::template
|
|
_MoveCopyPair<true, _U1, _T2>(),
|
|
bool>::type=true>
|
|
constexpr pair(_U1&& __x, const _T2& __y)
|
|
: first(std::forward<_U1>(__x)), second(__y) { }
|
|
|
|
template<typename _U1, typename
|
|
enable_if<_PCCP::template
|
|
_MoveCopyPair<false, _U1, _T2>(),
|
|
bool>::type=false>
|
|
explicit constexpr pair(_U1&& __x, const _T2& __y)
|
|
: first(std::forward<_U1>(__x)), second(__y) { }
|
|
|
|
template<typename _U2, typename
|
|
enable_if<_PCCP::template
|
|
_CopyMovePair<true, _T1, _U2>(),
|
|
bool>::type=true>
|
|
constexpr pair(const _T1& __x, _U2&& __y)
|
|
: first(__x), second(std::forward<_U2>(__y)) { }
|
|
|
|
template<typename _U2, typename
|
|
enable_if<_PCCP::template
|
|
_CopyMovePair<false, _T1, _U2>(),
|
|
bool>::type=false>
|
|
explicit pair(const _T1& __x, _U2&& __y)
|
|
: first(__x), second(std::forward<_U2>(__y)) { }
|
|
|
|
template<typename _U1, typename _U2, typename
|
|
enable_if<_PCCP::template
|
|
_MoveConstructiblePair<_U1, _U2>()
|
|
&& _PCCP::template
|
|
_ImplicitlyMoveConvertiblePair<_U1, _U2>(),
|
|
bool>::type=true>
|
|
constexpr pair(_U1&& __x, _U2&& __y)
|
|
: first(std::forward<_U1>(__x)), second(std::forward<_U2>(__y)) { }
|
|
|
|
template<typename _U1, typename _U2, typename
|
|
enable_if<_PCCP::template
|
|
_MoveConstructiblePair<_U1, _U2>()
|
|
&& !_PCCP::template
|
|
_ImplicitlyMoveConvertiblePair<_U1, _U2>(),
|
|
bool>::type=false>
|
|
explicit constexpr pair(_U1&& __x, _U2&& __y)
|
|
: first(std::forward<_U1>(__x)), second(std::forward<_U2>(__y)) { }
|
|
|
|
|
|
template<typename _U1, typename _U2, typename
|
|
enable_if<_PCCFP<_U1, _U2>::template
|
|
_MoveConstructiblePair<_U1, _U2>()
|
|
&& _PCCFP<_U1, _U2>::template
|
|
_ImplicitlyMoveConvertiblePair<_U1, _U2>(),
|
|
bool>::type=true>
|
|
constexpr pair(pair<_U1, _U2>&& __p)
|
|
: first(std::forward<_U1>(__p.first)),
|
|
second(std::forward<_U2>(__p.second)) { }
|
|
|
|
template<typename _U1, typename _U2, typename
|
|
enable_if<_PCCFP<_U1, _U2>::template
|
|
_MoveConstructiblePair<_U1, _U2>()
|
|
&& !_PCCFP<_U1, _U2>::template
|
|
_ImplicitlyMoveConvertiblePair<_U1, _U2>(),
|
|
bool>::type=false>
|
|
explicit constexpr pair(pair<_U1, _U2>&& __p)
|
|
: first(std::forward<_U1>(__p.first)),
|
|
second(std::forward<_U2>(__p.second)) { }
|
|
|
|
template<typename... _Args1, typename... _Args2>
|
|
_GLIBCXX20_CONSTEXPR
|
|
pair(piecewise_construct_t, tuple<_Args1...>, tuple<_Args2...>);
|
|
|
|
_GLIBCXX20_CONSTEXPR pair&
|
|
operator=(typename conditional<
|
|
__and_<is_copy_assignable<_T1>,
|
|
is_copy_assignable<_T2>>::value,
|
|
const pair&, const __nonesuch&>::type __p)
|
|
{
|
|
first = __p.first;
|
|
second = __p.second;
|
|
return *this;
|
|
}
|
|
|
|
_GLIBCXX20_CONSTEXPR pair&
|
|
operator=(typename conditional<
|
|
__and_<is_move_assignable<_T1>,
|
|
is_move_assignable<_T2>>::value,
|
|
pair&&, __nonesuch&&>::type __p)
|
|
noexcept(__and_<is_nothrow_move_assignable<_T1>,
|
|
is_nothrow_move_assignable<_T2>>::value)
|
|
{
|
|
first = std::forward<first_type>(__p.first);
|
|
second = std::forward<second_type>(__p.second);
|
|
return *this;
|
|
}
|
|
|
|
template<typename _U1, typename _U2>
|
|
_GLIBCXX20_CONSTEXPR
|
|
typename enable_if<__and_<is_assignable<_T1&, const _U1&>,
|
|
is_assignable<_T2&, const _U2&>>::value,
|
|
pair&>::type
|
|
operator=(const pair<_U1, _U2>& __p)
|
|
{
|
|
first = __p.first;
|
|
second = __p.second;
|
|
return *this;
|
|
}
|
|
|
|
template<typename _U1, typename _U2>
|
|
_GLIBCXX20_CONSTEXPR
|
|
typename enable_if<__and_<is_assignable<_T1&, _U1&&>,
|
|
is_assignable<_T2&, _U2&&>>::value,
|
|
pair&>::type
|
|
operator=(pair<_U1, _U2>&& __p)
|
|
{
|
|
first = std::forward<_U1>(__p.first);
|
|
second = std::forward<_U2>(__p.second);
|
|
return *this;
|
|
}
|
|
|
|
/// Swap the first members and then the second members.
|
|
_GLIBCXX20_CONSTEXPR void
|
|
swap(pair& __p)
|
|
noexcept(__and_<__is_nothrow_swappable<_T1>,
|
|
__is_nothrow_swappable<_T2>>::value)
|
|
{
|
|
using std::swap;
|
|
swap(first, __p.first);
|
|
swap(second, __p.second);
|
|
}
|
|
|
|
private:
|
|
template<typename... _Args1, size_t... _Indexes1,
|
|
typename... _Args2, size_t... _Indexes2>
|
|
_GLIBCXX20_CONSTEXPR
|
|
pair(tuple<_Args1...>&, tuple<_Args2...>&,
|
|
_Index_tuple<_Indexes1...>, _Index_tuple<_Indexes2...>);
|
|
#endif // C++11
|
|
};
|
|
|
|
/// @relates pair @{
|
|
|
|
#if __cpp_deduction_guides >= 201606
|
|
template<typename _T1, typename _T2> pair(_T1, _T2) -> pair<_T1, _T2>;
|
|
#endif
|
|
|
|
/// Two pairs of the same type are equal iff their members are equal.
|
|
template<typename _T1, typename _T2>
|
|
inline _GLIBCXX_CONSTEXPR bool
|
|
operator==(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
|
|
{ return __x.first == __y.first && __x.second == __y.second; }
|
|
|
|
#if __cpp_lib_three_way_comparison && __cpp_lib_concepts
|
|
template<typename _T1, typename _T2>
|
|
constexpr common_comparison_category_t<__detail::__synth3way_t<_T1>,
|
|
__detail::__synth3way_t<_T2>>
|
|
operator<=>(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
|
|
{
|
|
if (auto __c = __detail::__synth3way(__x.first, __y.first); __c != 0)
|
|
return __c;
|
|
return __detail::__synth3way(__x.second, __y.second);
|
|
}
|
|
#else
|
|
/** Defines a lexicographical order for pairs.
|
|
*
|
|
* For two pairs of the same type, `P` is ordered before `Q` if
|
|
* `P.first` is less than `Q.first`, or if `P.first` and `Q.first`
|
|
* are equivalent (neither is less than the other) and `P.second` is less
|
|
* than `Q.second`.
|
|
*/
|
|
template<typename _T1, typename _T2>
|
|
inline _GLIBCXX_CONSTEXPR bool
|
|
operator<(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
|
|
{ return __x.first < __y.first
|
|
|| (!(__y.first < __x.first) && __x.second < __y.second); }
|
|
|
|
/// Uses @c operator== to find the result.
|
|
template<typename _T1, typename _T2>
|
|
inline _GLIBCXX_CONSTEXPR bool
|
|
operator!=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
|
|
{ return !(__x == __y); }
|
|
|
|
/// Uses @c operator< to find the result.
|
|
template<typename _T1, typename _T2>
|
|
inline _GLIBCXX_CONSTEXPR bool
|
|
operator>(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
|
|
{ return __y < __x; }
|
|
|
|
/// Uses @c operator< to find the result.
|
|
template<typename _T1, typename _T2>
|
|
inline _GLIBCXX_CONSTEXPR bool
|
|
operator<=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
|
|
{ return !(__y < __x); }
|
|
|
|
/// Uses @c operator< to find the result.
|
|
template<typename _T1, typename _T2>
|
|
inline _GLIBCXX_CONSTEXPR bool
|
|
operator>=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
|
|
{ return !(__x < __y); }
|
|
#endif // !(three_way_comparison && concepts)
|
|
|
|
#if __cplusplus >= 201103L
|
|
/** Swap overload for pairs. Calls std::pair::swap().
|
|
*
|
|
* @note This std::swap overload is not declared in C++03 mode,
|
|
* which has performance implications, e.g. see https://gcc.gnu.org/PR38466
|
|
*/
|
|
template<typename _T1, typename _T2>
|
|
_GLIBCXX20_CONSTEXPR inline
|
|
#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
|
|
// Constrained free swap overload, see p0185r1
|
|
typename enable_if<__and_<__is_swappable<_T1>,
|
|
__is_swappable<_T2>>::value>::type
|
|
#else
|
|
void
|
|
#endif
|
|
swap(pair<_T1, _T2>& __x, pair<_T1, _T2>& __y)
|
|
noexcept(noexcept(__x.swap(__y)))
|
|
{ __x.swap(__y); }
|
|
|
|
#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
|
|
template<typename _T1, typename _T2>
|
|
typename enable_if<!__and_<__is_swappable<_T1>,
|
|
__is_swappable<_T2>>::value>::type
|
|
swap(pair<_T1, _T2>&, pair<_T1, _T2>&) = delete;
|
|
#endif
|
|
#endif // __cplusplus >= 201103L
|
|
|
|
/// @} relates pair
|
|
|
|
/**
|
|
* @brief A convenience wrapper for creating a pair from two objects.
|
|
* @param __x The first object.
|
|
* @param __y The second object.
|
|
* @return A newly-constructed pair<> object of the appropriate type.
|
|
*
|
|
* The C++98 standard says the objects are passed by reference-to-const,
|
|
* but C++03 says they are passed by value (this was LWG issue #181).
|
|
*
|
|
* Since C++11 they have been passed by forwarding reference and then
|
|
* forwarded to the new members of the pair. To create a pair with a
|
|
* member of reference type, pass a `reference_wrapper` to this function.
|
|
*/
|
|
// _GLIBCXX_RESOLVE_LIB_DEFECTS
|
|
// 181. make_pair() unintended behavior
|
|
#if __cplusplus >= 201103L
|
|
// NB: DR 706.
|
|
template<typename _T1, typename _T2>
|
|
constexpr pair<typename __decay_and_strip<_T1>::__type,
|
|
typename __decay_and_strip<_T2>::__type>
|
|
make_pair(_T1&& __x, _T2&& __y)
|
|
{
|
|
typedef typename __decay_and_strip<_T1>::__type __ds_type1;
|
|
typedef typename __decay_and_strip<_T2>::__type __ds_type2;
|
|
typedef pair<__ds_type1, __ds_type2> __pair_type;
|
|
return __pair_type(std::forward<_T1>(__x), std::forward<_T2>(__y));
|
|
}
|
|
#else
|
|
template<typename _T1, typename _T2>
|
|
inline pair<_T1, _T2>
|
|
make_pair(_T1 __x, _T2 __y)
|
|
{ return pair<_T1, _T2>(__x, __y); }
|
|
#endif
|
|
|
|
/// @}
|
|
|
|
_GLIBCXX_END_NAMESPACE_VERSION
|
|
} // namespace std
|
|
|
|
#endif /* _STL_PAIR_H */
|