std::istream_iterator<T,CharT,Traits,Distance>::~istream_iterator
From cppreference.com
                    
                                        
                    < cpp | iterator | istream iterator
                    
                                                            
                    ~istream_iterator();  | 
(until C++11) | |
|   ~istream_iterator() = default;  | 
(since C++11) | |
Destroys the iterator, including the cached value.
| 
 If std::is_trivially_destructible<T>::value is   | 
(since C++11) |