let rec get_token_list entry tokl last_tok tree =
                  match tree with
                  | Node
                      {
                        node = (Stoken _ | Skeyword _ as tok);
                        son = son;
                        brother = DeadEnd
                      } -> get_token_list entry (last_tok :: tokl) tok son
                  | _ ->
                      if tokl = []
                      then None
                      else
                        Some
                          (((List.rev (last_tok :: tokl)), last_tok, tree))