std::hash <std::experimental::optional>
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                    < cpp | experimental | optional
                    
                                                            
                    |   | After reviewing national body comments to n3690, this library component was voted out from C++14 working paper into a separate Technical Specification. It is not a part of the draft C++14 as of n3797. | 
| Defined in header  <experimental/optional> | ||
| template<class T> struct hash<std::experimental::optional<T>>; | (library fundamentals TS) | |
The template specialization of std::hash for the std::experimental::optional class allows users to obtain hashes of the values contained in optional objects.
[edit] Template parameters
| T | - | the type of the value contained in optionalobject. The specialization std::hash<T> must meet the requirements of class templatehash. | 
[edit] Example
| This section is incomplete Reason: no example | 
[edit] See also
| (C++11) | hash function object (class template) |