Defined in header <mdspan> | ||
---|---|---|
template< class IndexType, std::size_t... Extents > class extents; | (1) | (since C++23) |
template< class IndexType, std::size_t Rank > class dextents = /* see below */ | (2) | (since C++23) |
sizeof...(Extents)
. extents
. Let d
denote std::dynamic_extent
, each specialization of it dextents<TypeIndex, Rank>
is equivalent to extents<IndexType, /* d, d, ..., d (d repeats Rank times in total)*/>
.Each specialization of extents
models regular
and is TriviallyCopyable.
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 will 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. |
Rank | - | denotes the rank of an all-dynamic extents . |
Member type | Definition |
---|---|
index_type | IndexType |
size_type | std::make_unsigned_t<index_type> |
rank_type | std::size_t |
Typical implementations hold only one non-static data member:
dynamic-extents
of type std::array<index_type, rank_dynamic()>
, which stores the size of each dynamic extents. The name is for exposition only. constructs an extents (public member function) |
|
Observers |
|
[static] | returns the static rank of an extents (public static member function) |
[static] | returns the dynamic rank of an extents (public static member function) |
[static] | returns static extent size of an extents at a certain rank index (public static member function) |
returns dynamic extent size of an extents at a certain rank index (public member function) |
|
Public exposition-only helpers |
|
returns the product of extent size in range [ 0, i) (exposition-only member function) |
|
returns the product of extents size in range [ i + 1, rank()) (exposition-only member function) |
|
casts the input into an integer type (exposition-only member function) |
|
Private exposition-only helpers |
|
returns the number of dynamic extents below a certain rank index (exposition-only member function) |
|
returns the number r such that in range [ 0, r + 1) there is exactly i + 1 dynamic extents for a certain argument i (exposition-only member function) |
(C++23) | compare underlying extents in each dimension of two extents (function) |
(C++11) | obtains the number of dimensions of an array type (class template) |
(C++11) | obtains the size of an array type along a specified dimension (class template) |
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