MODULE; IMPORT Integer; IMPORT Fmt; PROCEDURE NFANode Compare (a, b: T): [-1 .. 1] = BEGIN RETURN Integer.Compare(a.ID, b.ID); END Compare; PROCEDUREEqual (a,b:T):BOOLEAN=BEGIN RETURN Compare(a,b)=0;END Equal; PROCEDUREHash (a: T): INTEGER = BEGIN RETURN a.ID; END Hash; PROCEDUREFormat (a: T): TEXT = BEGIN RETURN Fmt.Int(a.ID); END Format; BEGIN END NFANode.