std::error_category::error_category(3)

NAME
std::error_category::error_category - std::error_category::error_category

Synopsis
   constexpr error_category() noexcept; (1) (since C++11)
   error_category( const error_category& ) = delete; (2) (since C++11)
   1) Constructs the error category object.
   2) Copy constructor is deleted. error_category is neither MoveConstructible nor
   CopyConstructible.

Parameters
   (none)
   Defect reports
   The following behavior-changing defect reports were applied retroactively to
   previously published C++ standards.
      DR Applied to Behavior as published Correct behavior
   LWG 2145 C++11 error_category was not constructible default constructor added