std::error_category

 

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General utilities Date and time Function objects Formatting library (C++20) bitset hash (C++11) Relational operators (deprecated in C++20) rel_ops::operator!=rel_ops::operator> rel_ops::operator<=rel_ops::operator>= Integer comparison functions cmp_equalcmp_lesscmp_less_than (C++20)(C++20)(C++20)    cmp_not_equalcmp_greatercmp_greater_than (C++20)(C++20)(C++20) in_range (C++20) Swap and type operations swap ranges::swap (C++20) exchange (C++14) declval (C++11) to_underlying (C++23) forward (C++11) forward_like (C++23) move (C++11) move_if_noexcept (C++11) as_const (C++17) Common vocabulary types pair tuple (C++11) optional (C++17) any (C++17) variant (C++17) tuple_size (C++11) tuple_element (C++11) apply (C++17) make_from_tuple (C++17) expected (C++23) Elementary string conversions to_chars (C++17) from_chars (C++17) chars_format (C++17)

 

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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) System error support 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) Assertions assert Stacktrace stacktrace_entry (C++23) basic_stacktrace (C++23)

 

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<error_category::operator<=> (until C++20)(until C++20)(C++20)

 

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<operator<=> (removed in C++20)(removed in C++20)(C++20)	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)