functor import Application System String at 'x-oz://system/String.ozf' define fun {IsntNil X} case X of nil then false else true end end fun {ReverseWords In Split} local Tokens FilteredTokens Reversed Str in Tokens = {String.split In Split} FilteredTokens = {List.filter Tokens IsntNil} Reversed = {List.reverse FilteredTokens} Str = {String.join Reversed Split} {String.toAtom Str} end end in {System.print {ReverseWords " one two three four " " "}} {Application.exit 0} end