std::span<T,Extent>::operator[]
constexpr reference operator[](size_type idx) const; |
Returns a reference to the idx
-th element of the sequence. The behavior is undefined if idx
is out of range (i.e., if it is greater than or equal to size()
).
Parameters
idx | - | the index of the element to access |
Return value
A reference to the idx
-th element of the sequence, i.e., data()[idx]
Exceptions
Throws nothing.
Example
#include <iostream> #include <span> #include <utility> void reverse(std::span<int> span) { for (std::size_t i = 0, j = std::size(span); i < j; ++i) { --j; std::swap(span[i], span[j]); } } void print(std::span<const int> const span) { for (int element: span) { std::cout << element << ' '; } std::cout << '\n'; } int main() { int data[]{ 1, 2, 3, 4, 5 }; print(data); reverse(data); print(data); }
Output:
1 2 3 4 5 5 4 3 2 1
See also
returns a pointer to the beginning of the sequence of elements (public member function) |
|
returns the number of elements in the sequence (public member function) |
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