std::operator==,!=,<,<=>(std::error_code)

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Defined in header`<system_error>`
bool operator==(conststd::error_code& lhs, conststd::error_code& rhs)noexcept;	(1)	(since C++11)
bool operator!=(conststd::error_code& lhs, conststd::error_code& rhs)noexcept;	(2)	(since C++11) (until C++20)
bool operator<(conststd::error_code& lhs, conststd::error_code& rhs)noexcept;	(3)	(since C++11) (until C++20)
std::strong_ordering operator<=>(conststd::error_code& lhs, conststd::error_code& rhs)noexcept;	(4)	(since C++20)

Compares two error code objects.

1) Compareslhs andrhs for equality.

2) Compareslhs andrhs for equality.

3) Checks whetherlhs is less thanrhs.

4) Obtains three-way comparison result oflhs andrhs.

The<,<=,>,>=, and!= operators aresynthesized fromoperator<=> andoperator== respectively.

(since C++20)

[edit]Parameters

lhs, rhs

error codes to compare

[edit]Return value

1)true if the error category and error value compare equal.

2)true if the error category or error value compare are not equal.

3)true iflhs.category()< rhs.category(). Otherwise,true iflhs.category()== rhs.category()&& lhs.value()< rhs.value(). Otherwise,false.

4)lhs.category()<=> rhs.category() if it is notstd::strong_ordering::equal. Otherwise,lhs.value()<=> rhs.value().

[edit]See also

category	obtains the error_category for this error_code (public member function)[edit]
value	obtains the value of the`error_code` (public member function)[edit]
operator==operator!=operator<operator<=> (removed in C++20)(removed in C++20)(C++20)	compares`error_condition`s and`error_code`s (function)[edit]

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std::operator==,!=,<,<=>(std::error_code)

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