added helper -- cf. SET616^5
(* Title: HOL/TPTP/TPTP_Parser/tptp_proof.ML
Author: Nik Sultana, Cambridge University Computer Laboratory
Collection of functions for handling TPTP proofs.
*)
signature TPTP_PROOF =
sig
val extract_inference_info : (TPTP_Syntax.general_term * 'a list) option ->
(string * string list) option
end
structure TPTP_Proof : TPTP_PROOF =
struct
open TPTP_Syntax
(*Extract name of inference rule, and the inferences it relies on*)
(*This is tuned to work with LEO-II, and is brittle wrt upstream
changes of the proof protocol.*)
fun extract_inference_info annot =
let
fun get_line_id (General_Data (Number (Int_num, num))) = [num]
| get_line_id (General_Data (Atomic_Word name)) = [name]
| get_line_id (General_Term (Number (Int_num, num), _ (*e.g. a bind*))) = [num]
| get_line_id _ = []
(*e.g. General_Data (Application ("theory", [General_Data
(Atomic_Word "equality")])) -- which would come from E through LEO-II*)
in
case annot of
NONE => NONE
| SOME annot =>
(case annot of
(General_Data (Application ("inference",
[General_Data (Atomic_Word inference_name),
_,
General_List related_lines])), _) =>
(SOME (inference_name, map get_line_id related_lines |> List.concat))
| _ => NONE)
end
end