anchor.diff:      in
     let targMap = Map.ofList (List.map2 ft targOpts tparams) in
     let replace_typ_arg (t:typ):typ = subst_typ_name targMap t in
  -  let arg_typ t = (normalize_type_with_transform env (replace_typ_arg t) (Some OperandTyp)).norm_typ in
  +  let arg_typ t = replace_typ_arg t in
     arg_typ
   
   let compute_fun_instance (env:env) (u:unifier) (f:fun_decl) (ts_opt:typ list option):fun_instance =
  
positive.code:     // op in {+, -, *, /, %}
        let (t1, ae1) = infer_exp_force env u e1 None in
        let (t2, ae2) = infer_exp_force env u e2 None in
        let t = unify_int_bound t1 t2 op in
        norm_ret t (AE_Op (Bop op, [ae1; ae2]))
    | EOp (Bop (BAnd _ | BOr _) as op, [e1; e2]) ->
        let tv = u_next_type_var u in
  
negative.code:   | EOp (FieldOp (Id xf), [e1]) ->
      (
        let (t1, ae1) = infer_exp_force env u e1 expected_typ in
        let t1 = normalize_type env t1 in
        let t1 = t1.norm_typ in
        let x1 =
          match t1 with
          | TName (Id x1) | TApply (Id x1, _) -> x1
  