C++

Reference

<system_error>

error_category

public member function
<system_error>

std::relational operators (error_category)

(1)
bool operator== (const error_category& rhs) const noexcept;
(2)
bool operator!= (const error_category& rhs) const noexcept;
(3)
bool operator<  (const error_category& rhs) const noexcept;
Relational operators
These member functions compare whether two error_category objects are the same.

Two error_category objects only compare equal if they have the same address in memory:
1
 
this == &

The less-than relational operator (3) returns whether the left-hand side operand refers to an object whose reference goes before rhs in a total ordering of pointers, as if defined as:
1
2
3
 
bool error_category::operator< (const error_category& rhs) const noexcept {
  return less <const error_category*>()(this,&rhs);
}

Parameters

rhs
Another error_category object.

Return value

true if both objects are the same, false otherwise.