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

 

C++

Language

Standard Library Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

 

Utilities library

Type support (basic types, RTTI, type traits)
Dynamic memory management
Error handling
Program utilities
Variadic functions
Library feature-test macros
Date and time
Function objects
initializer_list (C++11)
bitset
hash (C++11)
integer_sequence (C++14)
Relational operators (deprecated in C++20)
rel_ops::operator!=rel_ops::operator>rel_ops::operator<=rel_ops::operator>=
Comparisons (C++20)
strong_order weak_order partial_order strong_equal weak_equal	strong_ordering weak_ordering partial_ordering strong_equality weak_equality	is_eqis_neqis_ltis_lteqis_gtis_gteq
common_comparison_category
Common vocabulary types
pair tuple (C++11) apply (C++17) make_from_tuple (C++17)	optional (C++17) any (C++17) variant (C++17)
Swap, forward and move
swap
exchange (C++14)
forward (C++11)
move (C++11)
move_if_noexcept (C++11)
Elementary string conversions
to_chars (C++17)
from_chars (C++17)
chars_format (C++17)
Type operations
declval (C++11)
as_const (C++17)
launder (C++17)

 

Error handling

Exception handling exception uncaught_exceptionuncaught_exceptions (until C++20)(C++17) exception_ptr (C++11) make_exception_ptr (C++11) current_exception (C++11) rethrow_exception (C++11) nested_exception (C++11) throw_with_nested (C++11) rethrow_if_nested (C++11) Exception handling failures terminate terminate_handler get_terminate (C++11) set_terminate bad_exception unexpected (until C++17) unexpected_handler (until C++17) get_unexpected (C++11)(until C++17) set_unexpected (until C++17) Contracts contract_violation (C++20)

Exception categories logic_error invalid_argument domain_error length_error out_of_range runtime_error range_error overflow_error underflow_error tx_exception (TM TS) Error codes Error codes errno Assertions assert system_error facility error_category (C++11) generic_category (C++11) system_category (C++11) error_condition (C++11) errc (C++11) error_code (C++11) system_error (C++11)

 

std::error_code

Member functions

error_code::error_code

error_code::operator=

error_code::assign

Modifiers

error_code::clear

Observers

error_code::value

error_code::category

error_code::default_error_condition

error_code::message

error_code::operator bool

Non-member functions

operator< operator== operator!=

operator<<

Helper classes

is_error_code_enum

hash<std::error_code>

 

Defined in header <system_error>
bool operator==( const error_code& lhs, const error_code& rhs ) noexcept;	(1)	(since C++11)
bool operator!=( const error_code& lhs, const error_code& rhs ) noexcept;	(1)	(since C++11)
bool operator<( const error_code& lhs, const error_code& rhs ) noexcept;	(1)	(since C++11)

Compares two error code objects.

1) Compares lhs and rhs for equality.

2) Compares lhs and rhs for equality.

3) Checks whether lhs is less than rhs.

Parameters

lhs, rhs

-

error codes to compare

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

See also

category	obtains the error_category for this error_code (public member function)
value	obtains the value of the error_code (public member function)
operator==operator!=operator<	compares error_conditions and error_codes (function)