F45, Is id_null(x) TRUE for unitialized x ?

I have a package where a certain procedure is called a number of times. I use an id_null() against a variable of type RecordGroup held in the outer scope.

E.G.

PACKAGE BODY my_pack
IS

        PROCEDURE A
        IS
        

                PROCEDURE B
                IS
                        v_rg_id RecordGroup;
                        v_rg_name VARCHAR2(20) := 'my_group';

                        PROCEDURE C
                        IS
                        BEGIN
                                IF id_null(v_rg_id) THEN
                                        create the group
                                END IF;

                                ...
                        END C;
        
                BEGIN
                        LOOP
                                use PROCEDURE C
                        END LOOP;
                        delete_group(v_rg_id);
                END B;

        BEGIN
                LOOP;
                        use procedure B
                END LOOP;
        END A;

So, the record group has a lifetime within procedure B. Each time that A calls B, I should get a new record group as the scope of the v_rg_id is within B.

But, is my assumption that id_null(v_rg_id) will be true on each entry into procedure B a correct one, or should I really be checking for the group by name?

So far it seems to work OK, but that may just be luck!!

Thoughts?

-- 
Andy Hardy. PGP key available on request
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