std::mdspan<T,Extents,LayoutPolicy,AccessorPolicy>::operator[]

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< cpp‎ | container‎ | mdspan
 
 
 
 
template< class... OtherIndexTypes >
constexpr reference operator[]( OtherIndexTypes... indices ) const;
(1) (since C++23)
template< class OtherIndexType >
constexpr reference operator[]( std::span<OtherIndexType, rank()> indices ) const;
(2) (since C++23)
template< class OtherIndexType >
constexpr reference operator[]( const std::array<OtherIndexType, rank()>& indices ) const;
(3) (since C++23)

Returns a reference to the indicesth element of the mdspan.

1) Equivalent to return acc_.access(ptr_, map_(static_cast<index_type>(std::move(indices))...));.
  • This overload participates in overload resolution only if:
  • Let I be extents_type::index-cast(std::move(indices)). Then the behavior is undefined if I is not a multidimensional index in extents(), i.e., map_(I) < map_.required_span_size() is false.
2,3) Let P be a parameter pack such that std::is_same_v<make_index_sequence<rank()>, index_sequence<P...>> is true, then the operator is equivalent to return operator[](std::as_const(indices[P])...);.
  • This overload participates in overload resolution only if:

Parameters

indices - the indices of the element to access

Return value

A reference to the element

Example

See also