Structure Overload

signature Overload =
sig
 type hol_type = HolKernel.hol_type
 type term     = HolKernel.term

 type nthy_rec = {Name : string, Thy : string}
 type overloaded_op_info = {base_type : hol_type, actual_ops : term list,
                            tyavoids : hol_type list}


  type overload_info
  type printmap_data = term * string * int

  val null_oinfo : overload_info

  (* the parse map, taking strings to possible constants *)
  val oinfo_ops : overload_info -> (string * overloaded_op_info) list

  (* the print map, taking constants to at most one string *)
  val print_map : overload_info -> (nthy_rec * string) list

  structure PrintMap : LV_TERM_NET where type value = printmap_data
  val raw_print_map : overload_info -> PrintMap.lvtermnet

  val fupd_actual_ops :
    (term list -> term list) -> overloaded_op_info ->
    overloaded_op_info

  exception OVERLOAD_ERR of string

  val remove_overloaded_form :
    string -> overload_info -> overload_info * (term list * term list)

  val raw_map_insert :
    string -> (nthy_rec list * nthy_rec list) ->
    overload_info -> overload_info

  val info_for_name : overload_info -> string -> overloaded_op_info option
  val is_overloaded : overload_info -> string -> bool
  val overloading_of_term : overload_info -> Term.term -> string option
  val overloading_of_termP : overload_info -> (string -> bool) -> Term.term ->
                             string option
  val overloading_of_nametype :
    overload_info -> {Name : string, Thy : string} ->
    string option

  val add_actual_overloading:
    {opname: string, realname: string, realthy : string} ->
    overload_info -> overload_info

  val add_overloading : string * term -> overload_info -> overload_info
  val add_inferior_overloading : string * term -> overload_info -> overload_info

  val send_to_back_overloading:
    {opname: string, realname: string, realthy : string} ->
    overload_info -> overload_info

  val bring_to_front_overloading:
    {opname: string, realname: string, realthy : string} ->
    overload_info -> overload_info

  val merge_oinfos : overload_info -> overload_info -> overload_info

  val known_constants : overload_info -> string list

  val remove_mapping :
    string -> {Name:string, Thy:string} -> overload_info -> overload_info
  val gen_remove_mapping : string -> term -> overload_info -> overload_info

  val oi_strip_comb : overload_info -> term -> (term * term list) option
  val oi_strip_combP : overload_info -> (string -> bool) -> term ->
                       (term * term list) option

end

(* [oi_strip_comb oinfo t] returns SOME(f, args, pattern) if the the term t
   matches the pattern orig in the overload info's print-map, and this pattern
   decomposes t into operator f applied to arguments args.

   Further, this is the best such match, according to the heuristics
   that overloading uses.
*)

HOL 4, Kananaskis-10