CREATE OR ALTER PACKAGE TEST_A
AS
begin

procedure "Assign"(
    a int,
    b int = null
);

procedure proc1(arg1 int);

function test2(a int) returns int;
 
end;

RECREATE PACKAGE BODY TEST_A
AS
begin

procedure proc1(arg1 int)
as
begin
end
function test2(a int) returns int
as
begin
    return a + 1;
end

procedure "Assign"(
    a int,
    b int)
as
begin
    execute procedure proc1(a + test2(coalesce(b,5)));
end

end;