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std::_Optional_base< _Tp, bool, bool > Struct Template Reference
Utilities
Inheritance diagram for std::_Optional_base< _Tp, bool, bool >:
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Public Member Functions

constexpr _Optional_base (_Optional_base &&__other) noexcept(is_nothrow_move_constructible_v< _Tp >)
 
constexpr _Optional_base (const _Optional_base &__other)
 
template<typename... _Args, enable_if_t< is_constructible_v< _Tp, _Args... >, bool > = false>
constexpr _Optional_base (in_place_t, _Args &&... __args)
 
template<typename _Up , typename... _Args, enable_if_t< is_constructible_v< _Tp, initializer_list< _Up > &, _Args... >, bool > = false>
constexpr _Optional_base (in_place_t, initializer_list< _Up > __il, _Args &&... __args)
 
_Optional_base & operator= (_Optional_base &&)=default
 
_Optional_base & operator= (const _Optional_base &)=default
 

Public Attributes

_Optional_payload< _Tp > _M_payload
 

Protected Types

using _Stored_type = remove_const_t< _Tp >
 

Protected Member Functions

template<typename... _Args>
constexpr void _M_construct (_Args &&... __args) noexcept(is_nothrow_constructible_v< _Stored_type, _Args... >)
 
constexpr void _M_destruct () noexcept
 
constexpr const _Tp & _M_get () const noexcept
 
constexpr _Tp & _M_get () noexcept
 
constexpr bool _M_is_engaged () const noexcept
 
constexpr void _M_reset () noexcept
 

Detailed Description

template<typename _Tp, bool = is_trivially_copy_constructible_v<_Tp>, bool = is_trivially_move_constructible_v<_Tp>>
struct std::_Optional_base< _Tp, bool, bool >

Class template that provides copy/move constructors of optional.

Such a separate base class template is necessary in order to conditionally make copy/move constructors trivial.

When the contained value is trivially copy/move constructible, the copy/move constructors of _Optional_base will invoke the trivial copy/move constructor of _Optional_payload. Otherwise, they will invoke _Optional_payload(bool, const _Optional_payload&) or _Optional_payload(bool, _Optional_payload&&) to initialize the contained value, if copying/moving an engaged optional.

Whether the other special members are trivial is determined by the _Optional_payload<_Tp> specialization used for the _M_payload member.

See also
optional, _Enable_special_members

Definition at line 510 of file optional.

Member Typedef Documentation

◆ _Stored_type

template<typename _Tp , typename _Dp >
using std::_Optional_base_impl< _Tp, _Dp >::_Stored_type = remove_const_t<_Tp>
protectedinherited

Definition at line 448 of file optional.

Constructor & Destructor Documentation

◆ _Optional_base() [1/4]

template<typename _Tp , bool = is_trivially_copy_constructible_v<_Tp>, bool = is_trivially_move_constructible_v<_Tp>>
template<typename... _Args, enable_if_t< is_constructible_v< _Tp, _Args... >, bool > = false>
constexpr std::_Optional_base< _Tp, bool, bool >::_Optional_base ( in_place_t  ,
_Args &&...  __args 
)
inlineexplicitconstexpr

Definition at line 520 of file optional.

◆ _Optional_base() [2/4]

template<typename _Tp , bool = is_trivially_copy_constructible_v<_Tp>, bool = is_trivially_move_constructible_v<_Tp>>
template<typename _Up , typename... _Args, enable_if_t< is_constructible_v< _Tp, initializer_list< _Up > &, _Args... >, bool > = false>
constexpr std::_Optional_base< _Tp, bool, bool >::_Optional_base ( in_place_t  ,
initializer_list< _Up >  __il,
_Args &&...  __args 
)
inlineexplicitconstexpr

Definition at line 529 of file optional.

◆ _Optional_base() [3/4]

template<typename _Tp , bool = is_trivially_copy_constructible_v<_Tp>, bool = is_trivially_move_constructible_v<_Tp>>
constexpr std::_Optional_base< _Tp, bool, bool >::_Optional_base ( const _Optional_base< _Tp, bool, bool > &  __other)
inlineconstexpr

Definition at line 537 of file optional.

◆ _Optional_base() [4/4]

template<typename _Tp , bool = is_trivially_copy_constructible_v<_Tp>, bool = is_trivially_move_constructible_v<_Tp>>
constexpr std::_Optional_base< _Tp, bool, bool >::_Optional_base ( _Optional_base< _Tp, bool, bool > &&  __other)
inlineconstexprnoexcept

Definition at line 542 of file optional.

Member Function Documentation

◆ _M_construct()

template<typename _Tp , typename _Dp >
template<typename... _Args>
constexpr void std::_Optional_base_impl< _Tp, _Dp >::_M_construct ( _Args &&...  __args)
inlineconstexprprotectednoexceptinherited

Definition at line 454 of file optional.

◆ _M_destruct()

template<typename _Tp , typename _Dp >
constexpr void std::_Optional_base_impl< _Tp, _Dp >::_M_destruct ( )
inlineconstexprprotectednoexceptinherited

Definition at line 462 of file optional.

◆ _M_get() [1/2]

template<typename _Tp , typename _Dp >
constexpr const _Tp & std::_Optional_base_impl< _Tp, _Dp >::_M_get ( ) const
inlineconstexprprotectednoexceptinherited

Definition at line 482 of file optional.

◆ _M_get() [2/2]

template<typename _Tp , typename _Dp >
constexpr _Tp & std::_Optional_base_impl< _Tp, _Dp >::_M_get ( )
inlineconstexprprotectednoexceptinherited

Definition at line 475 of file optional.

◆ _M_is_engaged()

template<typename _Tp , typename _Dp >
constexpr bool std::_Optional_base_impl< _Tp, _Dp >::_M_is_engaged ( ) const
inlineconstexprprotectednoexceptinherited

Definition at line 470 of file optional.

◆ _M_reset()

template<typename _Tp , typename _Dp >
constexpr void std::_Optional_base_impl< _Tp, _Dp >::_M_reset ( )
inlineconstexprprotectednoexceptinherited

Definition at line 467 of file optional.

Member Data Documentation

◆ _M_payload

template<typename _Tp , bool = is_trivially_copy_constructible_v<_Tp>, bool = is_trivially_move_constructible_v<_Tp>>
_Optional_payload<_Tp> std::_Optional_base< _Tp, bool, bool >::_M_payload

Definition at line 552 of file optional.

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