std::error_category

 

C++

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Technical Specifications

 

Utilities library

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Error handling
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initializer_list (C++11)
bitset
hash (C++11)
integer_sequence (C++14)
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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
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pair tuple (C++11) apply (C++17) make_from_tuple (C++17)	optional (C++17) any (C++17) variant (C++17)
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swap
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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_category

Member functions

error_category::error_category

error_category::~error_category

error_category::name

error_category::default_error_condition

error_category::equivalent

error_category::message

error_category::operator==error_category::operator!=error_category::operator<

 

Defined in header <system_error>
class error_category;		(since C++11)

std::error_category serves as the base class for specific error category types, such as std::system_category, std::iostream_category, etc. Each specific category class defines the error_code - error_condition mapping and holds the explanatory strings for all error_conditions. The objects of error category classes are treated as singletons, passed by reference.

Member functions

(constructor)	constructs an error_category (public member function)
(destructor) [virtual]	destructs an error_category (virtual public member function)
operator= [deleted]	not copy assignable (public member function)
name [virtual]	obtains the name of the category (virtual public member function)
default_error_condition [virtual]	maps error_code to error_condition (virtual public member function)
equivalent [virtual]	compares error_code and error_condition for equivalence (virtual public member function)
message [virtual]	obtains the explanatory string (virtual public member function)
operator==operator!=operator<	compares two error categories (function)

Specific error categories

generic_category (C++11)	identifies the generic error category (function)
system_category (C++11)	identifies the operating system error category (function)
iostream_category (C++11)	identifies the iostream error category (function)
future_category (C++11)	identifies the future error category (function)

See also

error_condition (C++11)	holds a portable error code (class)
error_code (C++11)	holds a platform-dependent error code (class)