Can not call a static function with-in a instance of the object.

Question

Another FYI.
I wanted to keep all of the "option" input parameters values for a new object that
i am creating in one place. I thought that the easiest way would be to use a
static function that returns a value; one function for each option value.
I was looking for a way to define "constants" that are not stored in
the persistent data of the object, but could be reference each time
the object is used.
After creating the static functions in both the "type" and "body" components,
I created the method that acutally receives the option input values.
In this method I used a "case" statement. I tested the input parameter
value, which should be one of the option values.
I used a set of "WHEN conditions" that called the same
static functions to get the exact same values that the user should
pass in.
When I try to store this new version, I get the error:
"PLS-00587: a static method cannot be invoked on an instance value"
It points to the first "when statifc_function()" of the case function.
This seems weird!
If I can call the static method from the "type object" without creating
and instance of an object, then why can't I call it within the body
of a method of an instance of the object type?
This doesn't seem appropriate,
unless this implementation of objects is trying to avoid some type
of "recursion"?
If there is some other reason, I can not think of it.
Any ideas?

Answer 1

Sorry for the confusion. Here is the simplest example of what
I want to accomplish.
The anonymous block is a testing of the object type, which definition follows.
declare
test audit_info;
begin
test := audit_info(...);
test.testcall( audit_info.t_EMPLOYER() );
end;
-- * ========================================== * --
create or replace type audit_info as object
( seq_key integer
, static function t_EMPLOYER return varchar2
, member procedure test_call(input_type varchar2)
instantiable
final;
create or replace type body audit_info
as
( id audit_info
static function t_EMPLOYER return varchar2
as
begin
return 'EMPLOYER';
end;
member procedure test_call(input_type varchar2)
as
begin
CASE input_type
WHEN t_EMPLOYER()
select * from dual;
WHEN ...
end case;
end;
end;
The error occurs on the "WHEN t_EMPLOYER()" line. This code is only
an example.
Thanks.