std::span<T,Extent>::begin
constexpr iterator begin() const noexcept; |
Returns an iterator to the first element of the span
.
If the span
is empty, the returned iterator will be equal to end()
.
Parameters
(none).
Return value
Iterator to the first element.
Complexity
Constant.
Example
#include <span> #include <iostream> void print(std::span<const int> sp) { for(auto it = sp.begin(); it != sp.end(); ++it) { std::cout << *it << ' '; } std::cout << '\n'; } void transmogrify(std::span<int> sp) { if (!sp.empty()) { std::cout << *sp.begin() << '\n'; *sp.begin() = 2; } } int main() { int array[] { 1, 3, 4, 5 }; print(array); transmogrify(array); print(array); }
Output:
1 3 4 5 1 2 3 4 5
See also
(C++20)
|
returns an iterator to the end (public member function) |
(C++11)(C++14)
|
returns an iterator to the beginning of a container or array (function template) |
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