array a <one two three>
reference to array a <ARRAY(0x148bac)>
reference to anon array containing reference to array <ARRAY(0x138a6c)>
contents of array referred to by $bb <ARRAY(0x148bac)>
reference to the array referred to by $aa <ARRAY(0x148bac)>
contents of array referred to by $cc, or array a <one two three>