std::hash<std::error_condition>
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                    < cpp | error | error condition
                    
                                                            
                    |   Defined in header  <system_error>
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|   template<> struct hash<std::error_condition>;  | 
(since C++17) | |
The template specialization of std::hash for std::error_condition allows users to obtain hashes of objects of type std::error_condition.