std::array<T,N>::swap (3) - Linux Manuals
void swap( array& other ) noexcept(/* see below */); (since C++11)
constexpr void swap( array& other ) noexcept(/* see below */); (since C++20)
Exchanges the contents of the container with those of other. Does not cause iterators and references to associate with the other container.
other - container to exchange the contents with
noexcept(noexcept(swap(std::declval<T&>(), std::declval<T&>()))) (until C++17)
In the expression above, the identifier swap is looked up in the same manner as the one used by the C++17 std::is_nothrow_swappable trait.
noexcept specification: (since C++17)
For zero-sized arrays,
Linear in size of the container.
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR Applied to Behavior as published Correct behavior
LWG_2456 C++11 the noexcept specification is ill-formed made to work
std::swap(std::array) specializes the std::swap algorithm