std::error_category:: operator==,!=,<,<=>

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Utilities library
General utilities
Relational operators (deprecated in C++20)
std::error_category
Member functions
error_category::operator== error_category::operator!= error_category::operator< error_category::operator<=>
(until C++20) (until C++20) (C++20)
bool operator == ( const error_category & rhs ) const noexcept ;
(1) (since C++11)
bool operator ! = ( const error_category & rhs ) const noexcept ;
(2) (since C++11)
(until C++20)
bool operator < ( const error_category & rhs ) const noexcept ;
(3) (since C++11)
(until C++20)
std:: strong_ordering operator <=> ( const error_category & rhs ) const noexcept ;
(4) (since C++20)

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 ) .
4) Orders * this and rhs by the order of this and & rhs . Equivalent to std:: compare_three_way ( ) ( this, & rhs ) .

The < , <= , > , >= , and != operators are synthesized from operator <=> and operator == respectively.

(since C++20)

Parameters

rhs - specifies the error_category to compare

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 .
4) std :: strong_order :: less if * this is less than rhs as defined by the order of this and & rhs , otherwise std :: strong_order :: greater if rhs is less than * this in the order, otherwise std :: strong_order :: equal .