I need to produce such array :

root = ["22", "friend 22", ["11", "contact 11", [ ]  ] , ["13", 
"contact 13"], ["17", "contact 17"]]
writing

root[0] = friend.id_to_s
root[1] = friend.pseudo

then for each friend.contact , I write an array
	friend_array[0] = contact.id.to_s
	friend_array[1] = contact.pseudo
... then I would like to write
          friend_array[2] = [?]  if contact.info.count > 0
.. I need to write an empty array in this case...  (otherwise there is 
no friend_array[2] )

how can I write it ?

tfyl

joss