std::regex_error::regex_error
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                    < cpp | regex | regex error
                    
                                                            
                    |   Defined in header  <regex>
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|   regex_error( std::regex_constants::error_type ecode );  | 
(1) | (since C++11) | 
|   regex_error( const regex_error& other );  | 
(2) | (since C++11) | 
2) Copy constructor. Initializes the contents with those of other. If *this and other both have dynamic type 
std::regex_error then std::strcmp(what(), other.what()) == 0.Parameters
| ecode | - | error code indicating the error raised in regular expression parsing | 
| other | - |  another regex_error object to copy
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See also
|    (C++11)  | 
  describes different types of matching errors  (typedef)  |