std::default_accessor

 

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std::mdspan

Member functions mdspan::mdspan mdspan::operator= Element access mdspan::operator[] Observers mdspan::rank mdspan::rank_dynamic mdspan::static_extent mdspan::extent mdspan::size mdspan::empty mdspan::stride mdspan::extents mdspan::data_handle mdspan::mapping mdspan::accessor mdspan::is_uniquemdspan::is_exhaustivemdspan::is_stridedmdspan::is_always_uniquemdspan::is_always_exhaustivemdspan::is_always_strided

Non-member functions swap(std::mdspan) Subviews submdspan (C++26) submdspan_extents (C++26) Helper types and templates extentsdextentsdims (C++26) default_accessor Layout mapping policies layout_left layout_right layout_stride layout_left_padded (C++26) layout_right_padded (C++26) Subviews helpers full_extent (C++26) strided_slice (C++26) submdspan_mapping_result (C++26) Deduction guides

 

Defined in header <mdspan>
template< class ElementType > class default_accessor;		(since C++23)

A specialization of std::default_accessor class template is the default AccessorPolicy used by std::mdspan if no user-specified accessor policy is provided.

Each specialization of default_accessor models semiregular and is TriviallyCopyable.

Template parameters

ElementType

-

the element type. Shall be a complete object type that is neither an abstract class type nor an array type. Otherwise, the program is ill-formed

Member types

Member type	Definition
offset_policy	default_accessor
element_type	ElementType
reference	ElementType&
data_handle_type	ElementType*

Member functions

(constructor)	constructs a default_accessor (public member function)
access	returns a nth element provided by arguments (public member function)
offset	returns a data handle advanced by an offset value (public member function)

std::default_accessor::default_accessor

constexpr default_accessor() noexcept = default;	(1)
template< class OtherElementType > constexpr default_accessor( default_accessor<OtherElementType> ) noexcept {}	(2)

1) Default constructs a default_accessor.

2) Constructs a default_accessor from default_accessor<OtherElementType>. The constructor has no visible effect. This overload participates in overload resolution only if std::is_convertible_v<OtherElementType(*)[], element_type(*)[]> is true.

std::default_accessor::access

constexpr reference access( data_handle_type p, std::size_t i ) const noexcept;

Equivalent to return p[i];.

std::default_accessor::offset

constexpr data_handle_type offset( data_handle_type p, std::size_t i ) const noexcept;

Equivalent to return p + i;.