std::array<T,N>::empty
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Tables
std::array
constexpr bool empty() const noexcept;
(since C++11)
Checks if the container has no elements.
Contents
[edit] Return value
true if the container is empty, false otherwise.
[edit] Complexity
Constant.
[edit] Example
The following code uses empty to check if a std::array contains any elements:
Run this code
#include <array> #include <iostream> int main() { std::array <int, 4> numbers{3, 1, 4, 1}; std::array <int, 0> no_numbers; std::cout << std::boolalpha ; std::cout << "numbers.empty(): " << numbers.empty() << '\n'; std::cout << "no_numbers.empty(): " << no_numbers.empty() << '\n'; }
Output:
numbers.empty(): false no_numbers.empty(): true