std::span<T,Extent>::empty

 

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[[nodiscard]] constexpr bool empty() const noexcept;		(since C++20)

Checks if the span is empty.

Parameters

(none)

Return value

true if the span is empty (i.e., size() == 0); false otherwise.

Example

Run this code

#include <iomanip>
#include <iostream>
#include <span>
 
int main()
{
    std::span<const char> span{"ABCDEF"};
 
    while (!span.empty())
    {
        std::cout << std::quoted(span.data()) << '\n';
        span = span.last(span.size() - 1);
    }
}

Output:

"ABCDEF"
"BCDEF"
"CDEF"
"DEF"
"EF"
"F"
""

See also

size (C++20)

returns the number of elements in the sequence (public member function)