std::error_category

 

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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 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) Stacktrace stacktrace_entry (C++23) basic_stacktrace (C++23) Debugging support is_debugger_present (C++26) breakpoint_if_debugging (C++26) breakpoint (C++26)

 

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)