Create or replace global subtype - oracle

Question

I know that I can create a subtype inside a package specification like:
CREATE OR REPLACE PACKAGE XY
AS
SUBTYPE type_sdebug IS VARCHAR (200);
...
END;
/
If I want to use the same subtype within another package then I need to redefine the same type again. Is there a way to create or replace a global subtype such as:
CREATE OR REPLACE TYPE STRING_ARRAY AS VARRAY(500) OF VARCHAR2(30);
/

Answer 1

As far as I know, SUBTYPEs are a PL/SQL feature, so you cannot create them globally. But nothing prevents you from using a type defined in your package XY in another package (e.g. AB):
CREATE OR REPLACE PACKAGE XY
AS
SUBTYPE type_sdebug IS VARCHAR (200);
END;
CREATE OR REPLACE PACKAGE AB
AS
PROCEDURE print_it(p_Debug in XY.type_sdebug);
END;
CREATE OR REPLACE PACKAGE BODY AB
AS
PROCEDURE print_it(p_Debug in XY.type_sdebug) is
begin
dbms_output.put_line(p_Debug);
end;
END;
declare
v_Debug XY.type_sdebug default 'hello world';
begin
ab.print_it(v_Debug);
end;

Answer 2

Now that I've read the question correctly *{;-) , according to the documentation you can indeed create a subtype:
"This statement shows how the subtype corporate_customer_typ in the sample oe schema was created. It is based on the customer_typ supertype created in the preceding example and adds the account_mgr_id attribute. A hypothetical name is given to the table so that you can duplicate this example in your test database:"
CREATE TYPE corporate_customer_typ_demo UNDER customer_typ
( account_mgr_id NUMBER(6)
);
You may need additional privileges to be able to do so though, according to the prerequisites for creating types:
"To create a subtype, you must have the UNDER ANY TYPE system privilege or the UNDER object privilege on the supertype."