std::pair< _T1, _T2 > Struct Template Reference

Inherits __pair_base< _T1, _T2 >.

## Public Types

typedef _T1 | first_type
typedef _T2 | second_type

## Public Member Functions

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>
constexpr | pair ()
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)
template<typename _U1 , typename _U2 , typename enable_if< _PCCP::template _MoveConstructiblePair< _U1, _U2 >() &&!_PCCP::template _ImplicitlyMoveConvertiblePair< _U1, _U2 >(), bool >::type = false>
constexpr | pair (_U1 &&__x, _U2 &&__y)
template<typename _U1 , typename enable_if< _PCCP::template _MoveCopyPair< true, _U1, _T2 >(), bool >::type = true>
constexpr | pair (_U1 &&__x, const _T2 &__y)
template<typename _U1 , typename enable_if< _PCCP::template _MoveCopyPair< false, _U1, _T2 >(), bool >::type = false>
constexpr | pair (_U1 &&__x, const _T2 &__y)
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)
template<typename _U1 = _T1, typename _U2 = _T2, typename enable_if< _PCCP::template _ConstructiblePair< _U1, _U2 >() &&!_PCCP::template _ImplicitlyConvertiblePair< _U1, _U2 >(), bool >::type = false>
constexpr | pair (const _T1 &__a, const _T2 &__b)
template<typename _U2 , typename enable_if< _PCCP::template _CopyMovePair< true, _T1, _U2 >(), bool >::type = true>
constexpr | pair (const _T1 &__x, _U2 &&__y)
template<typename _U2 , typename enable_if< _PCCP::template _CopyMovePair< false, _T1, _U2 >(), bool >::type = false>
| pair (const _T1 &__x, _U2 &&__y)
constexpr | pair (const pair &)=default
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)
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>
constexpr | pair (const pair< _U1, _U2 > &__p)
constexpr | pair (pair &&)=default
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)
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>
constexpr | pair (pair< _U1, _U2 > &&__p)
template<typename... _Args1, typename... _Args2>
constexpr | pair (piecewise_construct_t, tuple< _Args1... >, tuple< _Args2... >)
template<typename _U1 , typename _U2 >
constexpr enable_if< __and_< is_assignable< _T1 &, const _U1 & >, is_assignable< _T2 &, const _U2 & > >::value, pair & >::type | operator= (const pair< _U1, _U2 > &__p)
template<typename _U1 , typename _U2 >
constexpr enable_if< __and_< is_assignable< _T1 &, _U1 && >, is_assignable< _T2 &, _U2 && > >::value, pair & >::type | operator= (pair< _U1, _U2 > &&__p)
constexpr pair & | operator= (typename conditional< __and_< is_copy_assignable< _T1 >, is_copy_assignable< _T2 >>::value, const pair &, const __nonesuch & >::type __p)
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)
constexpr void | swap (pair &__p) noexcept(__and_< __is_nothrow_swappable< _T1 >, __is_nothrow_swappable< _T2 >>::value)

## Public Attributes

_T1 | first
_T2 | second

## Related Functions

(Note that these are not member functions.)
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)
template<typename _T1 , typename _T2 >
constexpr bool | operator== (const pair< _T1, _T2 > &__x, const pair< _T1, _T2 > &__y)
template<typename _T1 , typename _T2 >
constexpr bool | operator< (const pair< _T1, _T2 > &__x, const pair< _T1, _T2 > &__y)
template<typename _T1 , typename _T2 >
constexpr bool | operator!= (const pair< _T1, _T2 > &__x, const pair< _T1, _T2 > &__y)
template<typename _T1 , typename _T2 >
constexpr bool | operator> (const pair< _T1, _T2 > &__x, const pair< _T1, _T2 > &__y)
template<typename _T1 , typename _T2 >
constexpr bool | operator<= (const pair< _T1, _T2 > &__x, const pair< _T1, _T2 > &__y)
template<typename _T1 , typename _T2 >
constexpr bool | operator>= (const pair< _T1, _T2 > &__x, const pair< _T1, _T2 > &__y)
template<typename _T1 , typename _T2 >
constexpr enable_if< __and_< __is_swappable< _T1 >, __is_swappable< _T2 > >::value >::type | swap (pair< _T1, _T2 > &__x, pair< _T1, _T2 > &__y) noexcept(noexcept(__x.swap(__y)))

## Detailed Description

### template<typename _T1, typename _T2>
struct std::pair< _T1, _T2 >

Struct holding two objects of arbitrary type.

Template Parameters

  _T1 | Type of first object.
  _T2 | Type of second object.

https://gcc.gnu.org/onlinedocs/libstdc++/manual/utilities.html

Definition at line 211 of file stl_pair.h.

## Member Typedef Documentation

## first_type

template<typename _T1 , typename _T2 >

typedef _T1 std::pair< _T1, _T2 >::first_type

The type of the `first` member.

Definition at line 214 of file stl_pair.h.

## second_type

template<typename _T1 , typename _T2 >

typedef _T2 std::pair< _T1, _T2 >::second_type

The type of the `second` member.

Definition at line 215 of file stl_pair.h.

## Constructor & Destructor Documentation

## pair() [1/5]

template<typename _T1 , typename _T2 >
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>

constexpr std::pair< _T1, _T2 >::pair | ( |  | ) |

inline constexpr

The default constructor creates `first` and `second` using their respective default constructors.

Definition at line 232 of file stl_pair.h.

## pair() [2/5]

template<typename _T1 , typename _T2 >
template<typename _U1 = _T1, typename _U2 = _T2, typename enable_if< _PCCP::template _ConstructiblePair< _U1, _U2 >() &&_PCCP::template _ImplicitlyConvertiblePair< _U1, _U2 >(), bool >::type = true>

constexpr std::pair< _T1, _T2 >::pair | ( | const _T1 & | __a,
|  | const _T2 & | __b
| ) |  |

inline constexpr

Construct from two const lvalues, allowing implicit conversions.

Definition at line 266 of file stl_pair.h.

## pair() [3/5]

template<typename _T1 , typename _T2 >
template<typename _U1 = _T1, typename _U2 = _T2, typename enable_if< _PCCP::template _ConstructiblePair< _U1, _U2 >() &&!_PCCP::template _ImplicitlyConvertiblePair< _U1, _U2 >(), bool >::type = false>

constexpr std::pair< _T1, _T2 >::pair | ( | const _T1 & | __a,
|  | const _T2 & | __b
| ) |  |

inline explicit constexpr

Construct from two const lvalues, disallowing implicit conversions.

Definition at line 276 of file stl_pair.h.

## pair() [4/5]

template<typename _T1 , typename _T2 >

constexpr std::pair< _T1, _T2 >::pair | ( | const pair< _T1, _T2 > & |  | ) |

constexpr default

Copy constructor.

## pair() [5/5]

template<typename _T1 , typename _T2 >

constexpr std::pair< _T1, _T2 >::pair | ( | pair< _T1, _T2 > && |  | ) |

constexpr default

Move constructor.

## Member Function Documentation

## swap()

template<typename _T1 , typename _T2 >

constexpr void std::pair< _T1, _T2 >::swap | ( | pair< _T1, _T2 > & | __p | ) |

inline constexpr noexcept

Swap the first members and then the second members.

Definition at line 439 of file stl_pair.h.

References std::pair< _T1, _T2 >::first, std::pair< _T1, _T2 >::second, and std::swap().

Referenced by std::pair< _T1, _T2 >::swap().

## Member Data Documentation

## first

template<typename _T1 , typename _T2 >

_T1 std::pair< _T1, _T2 >::first

The first member.

Definition at line 217 of file stl_pair.h.

Referenced by std::_Temporary_buffer< _ForwardIterator, _Tp >::_Temporary_buffer(), __gnu_parallel::__find_template(), std::__sample(), std::set< _Key, _Compare, _Alloc >::insert(), std::pair< _T1, _T2 >::operator<(), std::pair< _T1, _T2 >::operator==(), and std::pair< _T1, _T2 >::swap().

## second

template<typename _T1 , typename _T2 >

_T2 std::pair< _T1, _T2 >::second

The second member.

Definition at line 218 of file stl_pair.h.

Referenced by std::__sample(), std::set< _Key, _Compare, _Alloc >::insert(), std::pair< _T1, _T2 >::operator<(), std::pair< _T1, _T2 >::operator==(), and std::pair< _T1, _T2 >::swap().

The documentation for this struct was generated from the following files:

- stl_pair.h
- tuple