> But, to answer your emmediate question: > > ZMZM = [] - The list Nil constructor > Z1T = ( ) - The 1-tuple constructor IIRC, the "1" is the number of commas, so Z1T is the *pair* constructor. --KW 8-) -- Keith Wansbrough <kw217@cl.cam.ac.uk> http://www.cl.cam.ac.uk/users/kw217/ University of Cambridge Computer Laboratory.