std::extents

 

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std::mdspan

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mdspan::mdspan

mdspan::operator=

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mdspan::operator[]

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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

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swap

Helper types and templates

extents

dextents

layout_right

layout_left

layout_stride

default_accessor

Deduction guides

 

Defined in header <mdspan>
template<class IndexType, std::size_t... Extents> class extents;		(since C++23)

The class template extents represents a multidimensional index space of rank equal to sizeof...(Extents).

Each specialization of extents models regular and is TriviallyCopyable.

Template parameters

IndexType	-	the type of each non-dynamic Extents. Shall be a signed or unsigned integer type. Otherwise, the program is ill-formed.
Extents	-	represents extent (size of an integer interval) for each rank index. Each element of it is either equal to std::dynamic_extent (in this case, it represents a dynamic extent and the extent size shall be determined dynamically), or is representable as a value of type IndexType (then it represents a static extent and the extent size is just the value of it), or else the program is ill-formed.

Member types

Member type	Definition
index_type	IndexType
size_type	std::make_unsigned_t<index_type>
rank_type	std::size_t

Data members

Typical implementations only hold one non-static data member:

• dynamic-extents in type std::array<index_type, rank_dynamic()>, stores the size of each dynamic extents. The name is for exposition only.

Member functions

(constructor)	constructs an extents (public member function)
Observers
rank [static]	returns the static rank of an extents (public static member function)
rank_dynamic [static]	returns the dynamic rank of an extents (public static member function)
static_extents [static]	returns static extent size of an extents at a certain rank index (public static member function)
extent	returns dynamic extent size of an extents at a certain rank index (public member function)
Public exposition-only helpers
fwd-prod-of-extents	returns the product of extent size in range [​0​, i). The name is for exposition only. (public member function)
rev-prod-of-extents	returns the product of extents size in range [i + 1, rank()). The name is for exposition only. (public member function)
index-cast	casts the input into an integer type. The name is for exposition only. (public member function)
Private exposition-only helpers
dynamic-index	returns the number of dynamic extents below a certain rank index. The name is for exposition only. (private member function)
dynamic-index-inv	returns the number r that in range [​0​, r + 1) there is exactly i + 1 dynamic extents for a certain argument i. The name is for exposition only. (private member function)

Non-member functions

operator==

compare underlying extents in each dimension of two extents (function)