std::experimental::observer_ptr::swap

From cppreference.com
constexpr void swap(observer_ptr& other);
(library fundamentals TS v2)

Swaps the watched object of *this and another observer_ptr object other, by invoking swap on the stored pointers of *this and other.

Parameters

other - another observer_ptr object to swap the watched object with

Return value

(none)

Exceptions

noexcept specification:  
noexcept
  

Example