std::reference_wrapper<T>::operator=
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                    < cpp | utility | functional | reference wrapper
                    
                                                            
                    |   reference_wrapper& operator=( const reference_wrapper<T>& other ) noexcept;  | 
(since C++11) | |
Copy assignment operator. Drops the current reference and stores a reference to other.get().
Parameters
| other | - | reference wrapper to copy | 
Return values
*this