is_error_code_enum Class
Represents a type predicate that tests for the error_code enumeration.
Syntax
template <_Enum>
class is_error_code_enum;
Remarks
An instance of this type predicate holds true if the type _Enum is an enumeration value suitable for storing in an object of type error_code.
It is permissible to add specializations to this type for user-defined types.