sql - Using an object type in a select statement in Oracle -

I have a function that returns an object with 3 values. Is there a way to call that function with a selection statement, and each value is a different column? I could break it in 3 functions, but the value is related, so I wanted to put it as one for display reasons. (I.e., Oracle does not need to call 3 identical complex functions for every line in the query.)

Type the following:

  Type test_obj object (a number, B NUMBER, C NUMBER); Create test_func or replace function (pinput number) with return test_obj returns test_obj (0, 0, 0); End test_func;  

I want to be able to call test_func from a select statement, but sometimes without calling the function, there can be columns A, B and C. I probably thought of something like that, but it does not work: choose

  iv.col1, iv.col2, iv.func_data.a, iv.func_data.b, iv.func_data.c From (Select MT Col1, mt.col2, test_func (mt.input) as func_data from my_table mt) iv  

Any method of doing something like this in Oracle 10G Is there a better way to solve this problem?