I am having trouble making this run: code: functor export generic:Generic define fun {Generic Op InitVal N} if N == 0 then InitVal else {Op N {Generic Op InitVal (N-1)}} end end end error: %************************* expansion error ********************** %** %** illegal use of nesting marker %** %** in file "Oz", line 2, column 0 %** ------------------ rejected (1 error)