sml-mode bug

gistfile1.ML

datatype type_node
  = Param of TyParam.t
  | LongId of LongTyId.t * tyargs_t option
  | Record of field_t list
  | Tuple of type_t list
  | Fun of type_t list * type_t list option * type_t list
  | Any
  | VProc
  | Cont of tyargs_t option
  | Addr of type_t
and tyargs_node
    = ArgTypes of type_t list
and dataconsdef_node
    = ConsDef of BomId.t * type_t option
and field_node
    = Immutable of IntInf.int * type_t
    | Mutable of IntInf.int * type_t
and fundef_node
    = Def of Attrs.t option * BomId.t * TyParams.t option
             * varpat_t list option * varpat_t list option * type_t list option * exp_t
and varpat_node
    = Wild of type_t option
    | Var of BomId.t * type_t option
and caserule_node
    = LongRule of LongConId.t * varpat_t list option * exp_t
    | LiteralRule of Literal.t * exp_t
    | DefaultRule of varpat_t * exp_t
and tycaserule_node
    = TyRule of type_t * exp_t
    | Default of exp_t
and simpleexp_node
    = PrimOp of PrimTycons.tycon * simpleexp_t list
    | AllocId of LongValueId.t * simpleexp_t list
    | AllocType of tyargs_t * simpleexp_t list
    | AtIndex of IntInf.int * simpleexp_t * simpleexp_t option
    | TypeCast of type_t * simpleexp_t
    | HostVproc
    | VpLoad of IntInf.int * simpleexp_t
    | VpAddr of IntInf.int * simpleexp_t
    | VpStore of IntInf.int * simpleexp_t * simpleexp_t
    | Id of LongValueId.t
    | Lit of Literal.t
    | MLString of IntInf.int vector
and exp_node
    = Let of varpat_t list * rhs_t * exp_t
    | Do of simpleexp_t * exp_t
    | FunExp of fundef_t list * exp_t
    | ContExp of BomId.t * varpat_t list option * exp_t * exp_t
    | If of simpleexp_t * exp_t * exp_t
    | Case of simpleexp_t * caserule_t list
            | Typecase of TyParam.t * tycaserule_t list
                        | Apply of LongValueId.t * simpleexp_t list option * simpleexp_t list option
                                 | Throw of BomId.t * tyargs_t option * simpleexp_t list option
                                          | Return of simpleexp_t list option
and rhs_node
    = Composite of exp_t
                 | Simple of simpleexp_t

                                 withtype type_t = type_node Wrap.t
and tyargs_t = tyargs_node Wrap.t
and dataconsdef_t = dataconsdef_node Wrap.t
and field_t = field_node  Wrap.t
and fundef_t = fundef_node Wrap.t
and varpat_t = varpat_node Wrap.t
and caserule_t = caserule_node Wrap.t
and tycaserule_t = tycaserule_node Wrap.t
and simpleexp_t = simpleexp_node Wrap.t
and exp_t = exp_node Wrap.t
and rhs_t = rhs_node Wrap.t