Match.purs

findX :: (MatchObj -> Maybe MatchObj) -> [String] -> Maybe MatchObj
findX matcher words = head xs
  where
    xs = do len <- length words .. 1
            idx <- 0 .. length words - len
            let m = matcher { before: take idx words
                            , group: (drop idx >>> take len) words
                            , after: drop (idx + len) words
                            , matches: defaultTransaction
                            , context: []
                            }
            guard $ isJust m
            return $ fromJust m