Oracle function to return temporary table

hi..

i need to make a function that returns a table that is populated within the function...

i can't create any object types.. so i can't have a predefined table with the fields i want returned

is there a way to create a temporary table type in a function, populate it and return it? where the temporary table type expires after the return?

this is basically the structure of the function i need

create function f(x,y,z) returns (table to be defined)
as
...
begin
   build temporary table
   return temp table
end;

Code (markup):

any ideas would be appreciated