std::error_category::operator==,!=,<
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                    < cpp | error | error category
                    
                                                            
                    | bool operator==( const error_category& rhs ) const; | (1) | (since C++11) | 
| bool operator!=( const error_category& rhs ) const; | (2) | (since C++11) | 
| bool operator<( const error_category& rhs ) const; | (3) | (since C++11) | 
Compares to another error category.
1) Checks whether *this and 
rhs refer to the same object.2) Checks whether *this and 
rhs do not refer to the same object.3) Orders *this and 
rhs by the order of this and &rhs. Equivalent to std::less<const error_category*>()(this, &rhs).[edit] Parameters
| code | - | specifies the error code to compare | 
| condition | - | specifies the error condition to compare | 
[edit] Return value
1) true if *this and 
rhs refer to the same object, false otherwise.2) true if *this and 
rhs do not refer to the same object, false otherwise.3) true if *this is less than 
rhs as defined by the order of this and &rhs.[edit] Exceptions
noexcept specification:  
noexcept
  

