type var = int * (* arity of variable*) int;;
type 'nf_nob i_var_ = [ `I of var * 'nf_nob Listx.listx | `Var of var ]
type 'nf_nob i_n_var_ = [ `N of int | 'nf_nob i_var_ ]
type ('nf_nob,'nf) i_num_var_ = [
  | 'nf_nob i_n_var_
  | `Match of ('nf_nob,'nf) i_num_var_ * (* originating var *) var * (*lift*) int * (*branches*)(int * 'nf) list ref * (*args*)'nf_nob list
]
type 'nf nf_nob_ = [ `Lam of (* was_unpacked *) bool * 'nf | `Pacman | ('nf nf_nob_,'nf) i_num_var_ ]
type nf = [ nf nf_nob_ | `Bottom  ]
type nf_nob = nf nf_nob_
type i_var = nf_nob i_var_;;
type i_n_var = nf_nob i_n_var_;;
type i_num_var = (nf_nob,nf) i_num_var_;;
val hd_of_i_var : i_var -> int
val hd_of : i_n_var -> int option
val arity_of_hd : i_n_var -> int
(* put t under n lambdas, lifting t accordingtly *)
val make_lams : nf -> int -> nf
val lift : int -> nf -> nf
val free_vars' : nf -> var list
val free_vars : nf -> int list
module ToScott :
  sig
    val scott_of_nf : nf -> Pure.Pure.t
  end
val print : ?l:string list -> nf -> string
val string_of_nf : [<nf] -> string
val cast_to_i_var : [< nf > `I `Var] -> i_var
val cast_to_i_n_var : [< nf > `I `N `Var] -> i_n_var
val cast_to_i_num_var : [< nf > `I `N `Match `Var] -> i_num_var
val set_arity : int -> nf -> nf
val mk_app : nf -> nf -> nf
val mk_appl : nf -> nf list -> nf
val mk_appx : nf -> nf Listx.listx -> nf
val mk_match : nf -> var -> int -> (int * nf) list ref -> nf list -> nf
val subst : bool -> bool -> int -> nf -> nf -> nf
val eta_compare : nf -> nf -> int
val eta_eq : [< nf ] -> [< nf ] -> bool
val eta_subterm : [< nf ] -> [< nf ] -> bool
val max_arity_tms : int -> [< nf] list -> int option
val minus1 : int -> int