std::hash(std::shared_ptr)
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                    < cpp | memory | shared ptr
                    
                                                            
                    | template<class T> struct hash<shared_ptr<T>>; | (since C++11) | |
The template specialization of std::hash for std::shared_ptr<T> allows users to obtain hashes of objects of type std::shared_ptr<T>.
For a given std::shared_ptr<T> p, this specialization ensures that
| std::hash<std::shared_ptr<T>>()(p) == std::hash<T*>()(p.get()). | (until C++17) | 
| std::hash<std::shared_ptr<typename std::shared_ptr<T>::element_type*>>()(p) == std::hash<T*>()(p.get()). | (since C++17) | 
Example
| This section is incomplete Reason: no example | 
See also
| (C++11) | hash function object (class template) |