std::layout_stride::mapping<Extents>::mapping-traits
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< cpp | container | mdspan | layout stride | mapping
static constexpr bool is_unique() noexcept; |
(1) | (since C++23) |
constexpr bool is_exhaustive() const noexcept; |
(2) | (since C++23) |
static constexpr bool is_strided() noexcept; |
(3) | (since C++23) |
static constexpr bool is_always_unique() noexcept; |
(4) | (since C++23) |
static constexpr bool is_always_exhaustive() noexcept; |
(5) | (since C++23) |
static constexpr bool is_always_strided() noexcept; |
(6) | (since C++23) |
Every instance of every specialization of mapping
is unique and strided.
The mapping is exhaustive if one of the following conditions is true
- rank_ is 0, or
- there exists a permutation p of the integers in the range
[
0,
rank_)
such that
- stride(p[0]) equals 1 and
- stride(p[i]) equals stride(p[i - 1]) * extents().extent(p[i - 1])
- for all i in
[
1,
rank_)
, where p[i] is the ith element of p.
(rank_ is an exposition-only static member constant defined in std::layout_stride::mapping.)
See LayoutMapping for the semantics of these predicate mapping traits.
目录 |
[编辑] 参数
(无)
[编辑] 返回值
1,3-4,6) true
2) true if the mapping is exhaustive (see above)
5) false
[编辑] 示例
本节不完整 原因:没有示例 |
[编辑] 另请参阅
本节不完整 |