std::packaged_task<R(Args...)>::swap
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                    < cpp | thread | packaged task
                    
                                                            
                    |   void swap( packaged_task& other ) noexcept;  | 
(since C++11) | |
Exchanges the shared states and stored tasks of *this and other.
Parameters
| other | - | packaged task whose state to swap with | 
Return value
(none)
See also
|    specializes the std::swap algorithm  (function template)  |