Stack.For_csttype t = | Emptyat top-level
*)| T_or_comment of Cst.t_or_comment * tafter the given sexp or comment
*)| Open of Positions.pos * tafter the opening paren
*)| In_sexp_comment of {hash_semi_pos : Positions.pos;rev_comments : Cst.comment list;stack : t;}In_sexp_comment only indicates if the next s-expression is to be commented out, but if we are nested below parens below an sexp comment, the stack would look like Open (.., In_sexp_comment ..).
val empty : tval get_many : t -> Cst.t_or_comment listRaises if t contains a partial sexp.