]> Dear caml-list I want to buidl a tree , so first i defined Node module Node= struct type 'a t = {id : int ; mutable anc : 'a t ; mutable child : 'a t array ; mutable content : 'a } let create i init = {id = i ; child = [||] ; content = init ; anc =????} .. end i dont know how to define the function var create : int -> 'a -> 'a t how to initiate anc ? but if in order to initiate anc easily , i define type 'a t = Empty | Some of { id :int ; mutable anc : 'a t .....} however syntex error :-( so, how to solve this problem? Thanks Yours climb onlyclimb@163.com 2002-12-16 ------------------- To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/ Beginner's list: http://groups.yahoo.com/group/ocaml_beginners