std::swap(std::function)
From cppreference.com
                    
                                        
                    < cpp | utility | functional | function
                    
                                                            
                    | template< class R, class... Args > void swap( function<R(Args...)> &lhs, function<R(Args...)> &rhs ); | ||
Overloads the std::swap algorithm for std::function. Exchanges the state of lhs with that of rhs. Effectively calls lhs.swap(rhs).
| Contents | 
[edit] Parameters
| lhs, rhs | - | polymorphic function wrappers whose states to swap | 
[edit] Return value
(none)
[edit] Exceptions
| (none) | (until C++17) | 
| noexcept specification:   noexcept | (since C++17) | 
[edit] Example
| This section is incomplete Reason: no example | 
[edit] See also
| swaps the contents (public member function) | 


