std::experimental::observer_ptr::swap
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                    < cpp | experimental | observer ptr
                    
                                                            
                    | 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
| This section is incomplete Reason: no example |