layout_right provides a layout mapping
where the rightmost extent is stride 1, and
strides increase right-to-left as the product of extents
. namespace std {
template<class Extents>
class layout_right::mapping {
public:
using extents_type = Extents;
using index_type = typename extents_type::index_type;
using size_type = typename extents_type::size_type;
using rank_type = typename extents_type::rank_type;
using layout_type = layout_right;
constexpr mapping() noexcept = default;
constexpr mapping(const mapping&) noexcept = default;
constexpr mapping(const extents_type&) noexcept;
template<class OtherExtents>
constexpr explicit(!is_convertible_v<OtherExtents, extents_type>)
mapping(const mapping<OtherExtents>&) noexcept;
template<class OtherExtents>
constexpr explicit(!is_convertible_v<OtherExtents, extents_type>)
mapping(const layout_left::mapping<OtherExtents>&) noexcept;
template<class OtherExtents>
constexpr explicit(extents_type::rank() > 0)
mapping(const layout_stride::mapping<OtherExtents>&) noexcept;
constexpr mapping& operator=(const mapping&) noexcept = default;
constexpr const extents_type& extents() const noexcept { return extents_; }
constexpr index_type required_span_size() const noexcept;
template<class... Indices>
constexpr index_type operator()(Indices...) const noexcept;
static constexpr bool is_always_unique() noexcept { return true; }
static constexpr bool is_always_exhaustive() noexcept { return true; }
static constexpr bool is_always_strided() noexcept { return true; }
static constexpr bool is_unique() noexcept { return true; }
static constexpr bool is_exhaustive() noexcept { return true; }
static constexpr bool is_strided() noexcept { return true; }
constexpr index_type stride(rank_type) const noexcept;
template<class OtherExtents>
friend constexpr bool operator==(const mapping&, const mapping<OtherExtents>&) noexcept;
private:
extents_type extents_{};
};
}