std::shared_future::operator=
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                    < cpp | thread | shared future
                    
                                                            
                    | shared_future& operator=(const shared_future& rhs); | (1) | (since C++11) | 
| shared_future& operator=(shared_future&& rhs) noexcept; | (2) | (since C++11) | 
| shared_future& operator=(future<R>&& other); | (3) | (since C++11) | 
| shared_future& operator=(shared_future&& other); | (4) | (since C++11) | 
| This section is incomplete | 


