4 let step k st outs ins =
5 if st = T.KO then k st outs ins else
7 | "main" :: tl -> k T.OK ("main" :: outs) tl
8 | "helper" :: tl -> k T.OK ("helper" :: outs) tl
9 | "basic" :: tl -> k T.OK ("basic" :: outs) tl
10 | "advanced" :: tl -> k T.OK ("advanced" :: outs) tl
11 | _ -> k T.OO outs ins