std::default_accessor

 

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mdspan::is_uniquemdspan::is_exhaustivemdspan::is_stridedmdspan::is_always_uniquemdspan::is_always_exhaustivemdspan::is_always_strided (C++23)(C++23)(C++23)(C++23)(C++23)(C++23)

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

The 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 that has an offset provided by arguments (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;.