[GiNaC-list] list of list

Hello List, I am rather a newbie in GiNaC and in C++ (but I am very familiar with another CAS and with C): I have just noticed that: lst list; list = lst(lst(1,1),lst(2,4),lst(3,9)); gives a list of list as expected, whereas lst list; list = lst(1,1),lst(2,4),lst(3,9); gives the first list (namely lst(1,1)) is it a bug ? or is it a wrong thing to do ? Thanks in advance, Jerome