src/HOL/Tools/Sledgehammer/sledgehammer_proof_reconstruct.ML
author blanchet
Tue Jul 27 12:01:02 2010 +0200 (2010-07-27)
changeset 38007 f0a4aa17f23f
parent 37998 f1b7fb87f523
child 38014 81c23d286f0c
permissions -rw-r--r--
handle Vampire's equality proxy axiom correctly
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(*  Title:      HOL/Tools/Sledgehammer/sledgehammer_proof_reconstruct.ML
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    Author:     Lawrence C Paulson and Claire Quigley, Cambridge University Computer Laboratory
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    Author:     Jasmin Blanchette, TU Muenchen
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Transfer of proofs from external provers.
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*)
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signature SLEDGEHAMMER_PROOF_RECONSTRUCT =
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sig
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  type minimize_command = string list -> string
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  val metis_line: bool -> int -> int -> string list -> string
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  val metis_proof_text:
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    bool * minimize_command * string * string vector * thm * int
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    -> string * string list
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  val isar_proof_text:
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    string Symtab.table * bool * int * Proof.context * int list
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    -> bool * minimize_command * string * string vector * thm * int
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    -> string * string list
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  val proof_text:
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    bool -> string Symtab.table * bool * int * Proof.context * int list
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    -> bool * minimize_command * string * string vector * thm * int
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    -> string * string list
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end;
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structure Sledgehammer_Proof_Reconstruct : SLEDGEHAMMER_PROOF_RECONSTRUCT =
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struct
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open Metis_Clauses
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open Sledgehammer_Util
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open Sledgehammer_Fact_Filter
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open Sledgehammer_TPTP_Format
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type minimize_command = string list -> string
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fun mk_anot phi = AConn (ANot, [phi])
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fun mk_aconn c (phi1, phi2) = AConn (c, [phi1, phi2])
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val index_in_shape : int -> int list -> int = find_index o curry (op =)
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fun is_axiom_clause_number thm_names num =
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  num > 0 andalso num <= Vector.length thm_names andalso
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  Vector.sub (thm_names, num - 1) <> ""
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fun is_conjecture_clause_number conjecture_shape num =
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  index_in_shape num conjecture_shape >= 0
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fun negate_term (Const (@{const_name All}, T) $ Abs (s, T', t')) =
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    Const (@{const_name Ex}, T) $ Abs (s, T', negate_term t')
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  | negate_term (Const (@{const_name Ex}, T) $ Abs (s, T', t')) =
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    Const (@{const_name All}, T) $ Abs (s, T', negate_term t')
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  | negate_term (@{const "op -->"} $ t1 $ t2) =
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    @{const "op &"} $ t1 $ negate_term t2
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  | negate_term (@{const "op &"} $ t1 $ t2) =
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    @{const "op |"} $ negate_term t1 $ negate_term t2
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  | negate_term (@{const "op |"} $ t1 $ t2) =
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    @{const "op &"} $ negate_term t1 $ negate_term t2
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  | negate_term (@{const Not} $ t) = t
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  | negate_term t = @{const Not} $ t
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datatype ('a, 'b, 'c, 'd, 'e) raw_step =
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  Definition of 'a * 'b * 'c |
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  Inference of 'a * 'd * 'e list
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(**** PARSING OF TSTP FORMAT ****)
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datatype int_or_string = Str of string | Int of int
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(*Strings enclosed in single quotes, e.g. filenames*)
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val scan_quoted = $$ "'" |-- Scan.repeat (~$$ "'") --| $$ "'" >> implode;
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val scan_dollar_name =
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  Scan.repeat ($$ "$") -- Symbol.scan_id >> (fn (ss, s) => implode ss ^ s)
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(* needed for SPASS's output format *)
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fun repair_name _ "$true" = "c_True"
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  | repair_name _ "$false" = "c_False"
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  | repair_name _ "$$e" = "c_equal" (* seen in Vampire proofs *)
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  | repair_name _ "equal" = "c_equal" (* probably not needed *)
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  | repair_name pool s = Symtab.lookup pool s |> the_default s
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(* Generalized first-order terms, which include file names, numbers, etc. *)
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(* The "x" argument is not strictly necessary, but without it Poly/ML loops
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   forever at compile time. *)
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fun parse_generalized_term x =
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  (scan_quoted >> (fn s => ATerm (Str s, []))
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   || scan_dollar_name
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      -- Scan.optional ($$ "(" |-- parse_generalized_terms --| $$ ")") []
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      >> (fn (s, gs) => ATerm (Str s, gs))
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   || scan_integer >> (fn k => ATerm (Int k, []))
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   || $$ "(" |-- parse_generalized_term --| $$ ")"
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   || $$ "[" |-- Scan.optional parse_generalized_terms [] --| $$ "]"
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      >> curry ATerm (Str "list")) x
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and parse_generalized_terms x =
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  (parse_generalized_term ::: Scan.repeat ($$ "," |-- parse_generalized_term)) x
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fun parse_term pool x =
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  ((scan_dollar_name >> repair_name pool)
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    -- Scan.optional ($$ "(" |-- parse_terms pool --| $$ ")") [] >> ATerm) x
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and parse_terms pool x =
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  (parse_term pool ::: Scan.repeat ($$ "," |-- parse_term pool)) x
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fun parse_predicate_term pool =
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  parse_term pool -- Scan.option (Scan.option ($$ "!") --| $$ "="
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                                  -- parse_term pool)
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  >> (fn (u, NONE) => APred u
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       | (u1, SOME (NONE, u2)) => APred (ATerm ("c_equal", [u1, u2]))
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       | (u1, SOME (SOME _, u2)) =>
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         mk_anot (APred (ATerm ("c_equal", [u1, u2]))))
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fun fo_term_head (ATerm (s, _)) = s
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(* TPTP formulas are fully parenthesized, so we don't need to worry about
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   operator precedence. *)
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fun parse_formula pool x =
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  (($$ "(" |-- parse_formula pool --| $$ ")"
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    || ($$ "!" >> K AForall || $$ "?" >> K AExists)
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       --| $$ "[" -- parse_terms pool --| $$ "]" --| $$ ":"
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       -- parse_formula pool
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       >> (fn ((q, ts), phi) => AQuant (q, map fo_term_head ts, phi))
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    || $$ "~" |-- parse_formula pool >> mk_anot
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    || parse_predicate_term pool)
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   -- Scan.option ((Scan.this_string "=>" >> K AImplies
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                    || Scan.this_string "<=>" >> K AIff
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                    || Scan.this_string "<~>" >> K ANotIff
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                    || Scan.this_string "<=" >> K AIf
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                    || $$ "|" >> K AOr || $$ "&" >> K AAnd)
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                   -- parse_formula pool)
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   >> (fn (phi1, NONE) => phi1
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        | (phi1, SOME (c, phi2)) => mk_aconn c (phi1, phi2))) x
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fun ints_of_generalized_term (ATerm (label, gs)) =
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  fold ints_of_generalized_term gs #> (case label of Int k => cons k | _ => I)
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val parse_tstp_annotations =
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  Scan.optional ($$ "," |-- parse_generalized_term
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                   --| Scan.option ($$ "," |-- parse_generalized_terms)
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                 >> (fn g => ints_of_generalized_term g [])) []
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(* Syntax: (fof|cnf)\(<num>, <formula_role>, <cnf_formula> <annotations>\).
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   The <num> could be an identifier, but we assume integers. *)
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 fun parse_tstp_line pool =
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   ((Scan.this_string "fof" || Scan.this_string "cnf") -- $$ "(")
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     |-- scan_integer --| $$ "," -- Symbol.scan_id --| $$ ","
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     -- parse_formula pool -- parse_tstp_annotations --| $$ ")" --| $$ "."
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    >> (fn (((num, role), phi), deps) =>
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           case role of
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             "definition" =>
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             (case phi of
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                AConn (AIff, [phi1 as APred _, phi2]) =>
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                Definition (num, phi1, phi2)
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              | APred (ATerm ("$$e", _)) =>
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                Inference (num, phi, deps) (* Vampire's equality proxy axiom *)
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              | _ => raise Fail "malformed definition")
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           | _ => Inference (num, phi, deps))
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(**** PARSING OF SPASS OUTPUT ****)
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(* SPASS returns clause references of the form "x.y". We ignore "y", whose role
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   is not clear anyway. *)
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val parse_dot_name = scan_integer --| $$ "." --| scan_integer
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val parse_spass_annotations =
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  Scan.optional ($$ ":" |-- Scan.repeat (parse_dot_name
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                                         --| Scan.option ($$ ","))) []
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(* It is not clear why some literals are followed by sequences of stars and/or
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   pluses. We ignore them. *)
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fun parse_decorated_predicate_term pool =
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  parse_predicate_term pool --| Scan.repeat ($$ "*" || $$ "+" || $$ " ")
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fun mk_horn ([], []) = APred (ATerm ("c_False", []))
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  | mk_horn ([], pos_lits) = foldr1 (mk_aconn AOr) pos_lits
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  | mk_horn (neg_lits, []) = mk_anot (foldr1 (mk_aconn AAnd) neg_lits)
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  | mk_horn (neg_lits, pos_lits) =
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    mk_aconn AImplies (foldr1 (mk_aconn AAnd) neg_lits,
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                       foldr1 (mk_aconn AOr) pos_lits)
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fun parse_horn_clause pool =
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  Scan.repeat (parse_decorated_predicate_term pool) --| $$ "|" --| $$ "|"
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    -- Scan.repeat (parse_decorated_predicate_term pool) --| $$ "-" --| $$ ">"
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    -- Scan.repeat (parse_decorated_predicate_term pool)
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  >> (mk_horn o apfst (op @))
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(* Syntax: <num>[0:<inference><annotations>]
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   <cnf_formulas> || <cnf_formulas> -> <cnf_formulas>. *)
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fun parse_spass_line pool =
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  scan_integer --| $$ "[" --| $$ "0" --| $$ ":" --| Symbol.scan_id
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  -- parse_spass_annotations --| $$ "]" -- parse_horn_clause pool --| $$ "."
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  >> (fn ((num, deps), u) => Inference (num, u, deps))
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fun parse_line pool = parse_tstp_line pool || parse_spass_line pool
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fun parse_lines pool = Scan.repeat1 (parse_line pool)
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fun parse_proof pool =
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  fst o Scan.finite Symbol.stopper
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            (Scan.error (!! (fn _ => raise Fail "unrecognized ATP output")
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                            (parse_lines pool)))
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  o explode o strip_spaces
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(**** INTERPRETATION OF TSTP SYNTAX TREES ****)
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exception FO_TERM of string fo_term list
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exception FORMULA of (string, string fo_term) formula list
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exception SAME of unit
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(* Type variables are given the basic sort "HOL.type". Some will later be
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   constrained by information from type literals, or by type inference. *)
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fun type_from_fo_term tfrees (u as ATerm (a, us)) =
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  let val Ts = map (type_from_fo_term tfrees) us in
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    case strip_prefix_and_undo_ascii type_const_prefix a of
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      SOME b => Type (invert_const b, Ts)
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    | NONE =>
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      if not (null us) then
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        raise FO_TERM [u]  (* only "tconst"s have type arguments *)
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      else case strip_prefix_and_undo_ascii tfree_prefix a of
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        SOME b =>
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        let val s = "'" ^ b in
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          TFree (s, AList.lookup (op =) tfrees s |> the_default HOLogic.typeS)
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        end
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      | NONE =>
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        case strip_prefix_and_undo_ascii tvar_prefix a of
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          SOME b => TVar (("'" ^ b, 0), HOLogic.typeS)
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        | NONE =>
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          (* Variable from the ATP, say "X1" *)
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          Type_Infer.param 0 (a, HOLogic.typeS)
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  end
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fun fix_atp_variable_name s =
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  let
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    fun subscript_name s n = s ^ nat_subscript n
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    val s = String.map Char.toLower s
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  in
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    case space_explode "_" s of
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      [_] => (case take_suffix Char.isDigit (String.explode s) of
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                (cs1 as _ :: _, cs2 as _ :: _) =>
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                subscript_name (String.implode cs1)
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                               (the (Int.fromString (String.implode cs2)))
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              | (_, _) => s)
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    | [s1, s2] => (case Int.fromString s2 of
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                     SOME n => subscript_name s1 n
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                   | NONE => s)
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    | _ => s
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  end
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(* First-order translation. No types are known for variables. "HOLogic.typeT"
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   should allow them to be inferred.*)
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fun term_from_fo_term thy full_types tfrees opt_T =
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  let
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    fun aux opt_T extra_us u =
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      case u of
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        ATerm ("hBOOL", [u1]) => aux (SOME @{typ bool}) [] u1
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      | ATerm ("hAPP", [u1, u2]) => aux opt_T (u2 :: extra_us) u1
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      | ATerm (a, us) =>
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        if a = type_wrapper_name then
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          case us of
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            [typ_u, term_u] =>
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            aux (SOME (type_from_fo_term tfrees typ_u)) extra_us term_u
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          | _ => raise FO_TERM us
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        else case strip_prefix_and_undo_ascii const_prefix a of
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          SOME "equal" =>
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          list_comb (Const (@{const_name "op ="}, HOLogic.typeT),
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                     map (aux NONE []) us)
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        | SOME b =>
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          let
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            val c = invert_const b
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            val num_type_args = num_type_args thy c
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            val (type_us, term_us) =
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              chop (if full_types then 0 else num_type_args) us
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            (* Extra args from "hAPP" come after any arguments given directly to
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               the constant. *)
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            val term_ts = map (aux NONE []) term_us
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            val extra_ts = map (aux NONE []) extra_us
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            val t =
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              Const (c, if full_types then
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                          case opt_T of
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                            SOME T => map fastype_of term_ts ---> T
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                          | NONE =>
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                            if num_type_args = 0 then
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                              Sign.const_instance thy (c, [])
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                            else
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                              raise Fail ("no type information for " ^ quote c)
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                        else
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                          Sign.const_instance thy (c,
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                              map (type_from_fo_term tfrees) type_us))
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          in list_comb (t, term_ts @ extra_ts) end
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        | NONE => (* a free or schematic variable *)
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          let
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            val ts = map (aux NONE []) (us @ extra_us)
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            val T = map fastype_of ts ---> HOLogic.typeT
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            val t =
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              case strip_prefix_and_undo_ascii fixed_var_prefix a of
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                SOME b => Free (b, T)
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              | NONE =>
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                case strip_prefix_and_undo_ascii schematic_var_prefix a of
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                  SOME b => Var ((b, 0), T)
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                | NONE =>
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                  (* Variable from the ATP, say "X1" *)
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                  Var ((fix_atp_variable_name a, 0), T)
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          in list_comb (t, ts) end
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  in aux opt_T [] end
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(* Type class literal applied to a type. Returns triple of polarity, class,
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   type. *)
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fun type_constraint_from_formula pos tfrees (AConn (ANot, [u])) =
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    type_constraint_from_formula (not pos) tfrees u
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  | type_constraint_from_formula pos tfrees (phi as APred (ATerm (a, us))) =
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    (case (strip_prefix_and_undo_ascii class_prefix a,
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   303
           map (type_from_fo_term tfrees) us) of
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   304
       (SOME b, [T]) => (pos, b, T)
blanchet@37991
   305
     | _ => raise FORMULA [phi])
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   306
  | type_constraint_from_formula _ _ phi = raise FORMULA [phi]
paulson@21978
   307
paulson@21978
   308
(** Accumulate type constraints in a clause: negative type literals **)
paulson@21978
   309
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   310
fun add_var (key, z)  = Vartab.map_default (key, []) (cons z)
paulson@21978
   311
blanchet@36909
   312
fun add_type_constraint (false, cl, TFree (a ,_)) = add_var ((a, ~1), cl)
blanchet@36909
   313
  | add_type_constraint (false, cl, TVar (ix, _)) = add_var (ix, cl)
blanchet@36909
   314
  | add_type_constraint _ = I
paulson@21978
   315
blanchet@36491
   316
fun is_positive_literal (@{const Not} $ _) = false
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   317
  | is_positive_literal _ = true
blanchet@36402
   318
blanchet@36555
   319
val combinator_table =
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   320
  [(@{const_name COMBI}, @{thm COMBI_def_raw}),
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   321
   (@{const_name COMBK}, @{thm COMBK_def_raw}),
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   322
   (@{const_name COMBB}, @{thm COMBB_def_raw}),
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   323
   (@{const_name COMBC}, @{thm COMBC_def_raw}),
blanchet@36555
   324
   (@{const_name COMBS}, @{thm COMBS_def_raw})]
blanchet@36555
   325
blanchet@36555
   326
fun uncombine_term (t1 $ t2) = betapply (pairself uncombine_term (t1, t2))
blanchet@36555
   327
  | uncombine_term (Abs (s, T, t')) = Abs (s, T, uncombine_term t')
blanchet@36555
   328
  | uncombine_term (t as Const (x as (s, _))) =
blanchet@36555
   329
    (case AList.lookup (op =) combinator_table s of
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   330
       SOME thm => thm |> prop_of |> specialize_type @{theory} x |> Logic.dest_equals |> snd
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   331
     | NONE => t)
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   332
  | uncombine_term t = t
blanchet@36555
   333
blanchet@37991
   334
fun disjuncts (AConn (AOr, phis)) = maps disjuncts phis
blanchet@37991
   335
  | disjuncts phi = [phi]
blanchet@37991
   336
blanchet@37991
   337
(* Update schematic type variables with detected sort constraints. It's not
blanchet@37991
   338
   totally clear when this code is necessary. *)
blanchet@37991
   339
fun repair_tvar_sorts (tvar_tab, t) =
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   340
  let
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   341
    fun do_type (Type (a, Ts)) = Type (a, map do_type Ts)
blanchet@37991
   342
      | do_type (TVar (xi, s)) =
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   343
        TVar (xi, the_default s (Vartab.lookup tvar_tab xi))
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   344
      | do_type (TFree z) = TFree z
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   345
    fun do_term (Const (a, T)) = Const (a, do_type T)
blanchet@37991
   346
      | do_term (Free (a, T)) = Free (a, do_type T)
blanchet@37991
   347
      | do_term (Var (xi, T)) = Var (xi, do_type T)
blanchet@37991
   348
      | do_term (t as Bound _) = t
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   349
      | do_term (Abs (a, T, t)) = Abs (a, do_type T, do_term t)
blanchet@37991
   350
      | do_term (t1 $ t2) = do_term t1 $ do_term t2
blanchet@37991
   351
  in t |> not (Vartab.is_empty tvar_tab) ? do_term end
blanchet@37991
   352
blanchet@37991
   353
fun s_disj (t1, @{const False}) = t1
blanchet@37991
   354
  | s_disj p = HOLogic.mk_disj p
blanchet@37991
   355
blanchet@37991
   356
fun quantify_over_free quant_s free_s body_t =
blanchet@37991
   357
  case Term.add_frees body_t [] |> filter (curry (op =) free_s o fst) of
blanchet@37991
   358
    [] => body_t
blanchet@37991
   359
  | frees as (_, free_T) :: _ =>
blanchet@37991
   360
    Abs (free_s, free_T, fold (curry abstract_over) (map Free frees) body_t)
blanchet@37991
   361
blanchet@37991
   362
 (* Interpret a list of syntax trees as a clause, given by "real" literals and
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   363
   sort constraints. Accumulates sort constraints in "tvar_tab", with "real"
blanchet@37991
   364
   literals in "lits". *)
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   365
fun prop_from_formula thy full_types tfrees =
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   366
   let
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   367
    val do_sort_constraint =
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   368
      add_type_constraint o type_constraint_from_formula true tfrees
blanchet@37991
   369
    fun do_real_literal phi =
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   370
      case phi of
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   371
        AQuant (_, [], phi) => do_real_literal phi
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   372
      | AQuant (q, x :: xs, phi') =>
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   373
        let
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   374
          val body = do_real_literal (AQuant (q, xs, phi'))
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   375
          val quant_s = case q of
blanchet@37991
   376
                          AForall => @{const_name All}
blanchet@37991
   377
                        | AExists => @{const_name Ex}
blanchet@37991
   378
        in quantify_over_free quant_s x body end
blanchet@37991
   379
      | AConn (ANot, [phi']) => HOLogic.mk_not (do_real_literal phi')
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   380
      | AConn (c, [phi1, phi2]) =>
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   381
        (phi1, phi2)
blanchet@37991
   382
        |> pairself do_real_literal
blanchet@37991
   383
        |> (case c of
blanchet@37991
   384
              AAnd => HOLogic.mk_conj
blanchet@37991
   385
            | AOr => HOLogic.mk_disj
blanchet@37991
   386
            | AImplies => HOLogic.mk_imp
blanchet@37991
   387
            | AIff => (fn (t1, t2) => HOLogic.eq_const HOLogic.boolT $ t1 $ t2))
blanchet@37991
   388
      | APred tm =>
blanchet@37991
   389
        term_from_fo_term thy full_types tfrees (SOME @{typ bool}) tm
blanchet@37991
   390
      | _ => raise FORMULA [phi]
blanchet@37991
   391
    fun do_literals (tvar_tab, t) [] = (tvar_tab, t)
blanchet@37991
   392
      | do_literals (tvar_tab, t) (u :: us) =
blanchet@37991
   393
        (do_literals (tvar_tab |> do_sort_constraint u, t) us
blanchet@37991
   394
         handle FO_TERM _ => raise SAME ()
blanchet@37991
   395
              | FORMULA _ => raise SAME ())
blanchet@37991
   396
        handle SAME () =>
blanchet@37991
   397
               do_literals (tvar_tab, s_disj (do_real_literal u, t)) us
blanchet@37991
   398
  in
blanchet@37991
   399
    repair_tvar_sorts o do_literals (Vartab.empty, HOLogic.false_const)
blanchet@37991
   400
    o disjuncts
blanchet@37991
   401
  end
blanchet@37991
   402
blanchet@36556
   403
fun check_formula ctxt =
wenzelm@37145
   404
  Type_Infer.constrain @{typ bool}
blanchet@36486
   405
  #> Syntax.check_term (ProofContext.set_mode ProofContext.mode_schematic ctxt)
paulson@21978
   406
paulson@21978
   407
paulson@21978
   408
(**** Translation of TSTP files to Isar Proofs ****)
paulson@21978
   409
blanchet@36486
   410
fun unvarify_term (Var ((s, 0), T)) = Free (s, T)
blanchet@36486
   411
  | unvarify_term t = raise TERM ("unvarify_term: non-Var", [t])
paulson@21978
   412
blanchet@37991
   413
fun decode_line full_types tfrees (Definition (num, phi1, phi2)) ctxt =
blanchet@36486
   414
    let
blanchet@37991
   415
      val thy = ProofContext.theory_of ctxt
blanchet@37991
   416
      val t1 = prop_from_formula thy full_types tfrees phi1
blanchet@36551
   417
      val vars = snd (strip_comb t1)
blanchet@36486
   418
      val frees = map unvarify_term vars
blanchet@36486
   419
      val unvarify_args = subst_atomic (vars ~~ frees)
blanchet@37991
   420
      val t2 = prop_from_formula thy full_types tfrees phi2
blanchet@36551
   421
      val (t1, t2) =
blanchet@36551
   422
        HOLogic.eq_const HOLogic.typeT $ t1 $ t2
blanchet@36556
   423
        |> unvarify_args |> uncombine_term |> check_formula ctxt
blanchet@36555
   424
        |> HOLogic.dest_eq
blanchet@36486
   425
    in
blanchet@36551
   426
      (Definition (num, t1, t2),
blanchet@36551
   427
       fold Variable.declare_term (maps OldTerm.term_frees [t1, t2]) ctxt)
blanchet@36486
   428
    end
blanchet@37991
   429
  | decode_line full_types tfrees (Inference (num, u, deps)) ctxt =
blanchet@36551
   430
    let
blanchet@37991
   431
      val thy = ProofContext.theory_of ctxt
blanchet@37991
   432
      val t = u |> prop_from_formula thy full_types tfrees
blanchet@37998
   433
                |> uncombine_term |> check_formula ctxt
blanchet@36551
   434
    in
blanchet@36551
   435
      (Inference (num, t, deps),
blanchet@36551
   436
       fold Variable.declare_term (OldTerm.term_frees t) ctxt)
blanchet@36486
   437
    end
blanchet@36967
   438
fun decode_lines ctxt full_types tfrees lines =
blanchet@36967
   439
  fst (fold_map (decode_line full_types tfrees) lines ctxt)
paulson@21978
   440
blanchet@37323
   441
fun aint_actual_inference _ (Definition _) = true
blanchet@37323
   442
  | aint_actual_inference t (Inference (_, t', _)) = not (t aconv t')
blanchet@36486
   443
blanchet@36486
   444
(* No "real" literals means only type information (tfree_tcs, clsrel, or
blanchet@36486
   445
   clsarity). *)
blanchet@36486
   446
val is_only_type_information = curry (op aconv) HOLogic.true_const
blanchet@36486
   447
blanchet@36486
   448
fun replace_one_dep (old, new) dep = if dep = old then new else [dep]
blanchet@36486
   449
fun replace_deps_in_line _ (line as Definition _) = line
blanchet@36486
   450
  | replace_deps_in_line p (Inference (num, t, deps)) =
blanchet@36486
   451
    Inference (num, t, fold (union (op =) o replace_one_dep p) deps [])
paulson@21978
   452
paulson@22491
   453
(*Discard axioms; consolidate adjacent lines that prove the same clause, since they differ
paulson@22491
   454
  only in type information.*)
blanchet@36551
   455
fun add_line _ _ (line as Definition _) lines = line :: lines
blanchet@36551
   456
  | add_line conjecture_shape thm_names (Inference (num, t, [])) lines =
blanchet@36570
   457
    (* No dependencies: axiom, conjecture clause, or internal axioms or
blanchet@36570
   458
       definitions (Vampire). *)
blanchet@36486
   459
    if is_axiom_clause_number thm_names num then
blanchet@36486
   460
      (* Axioms are not proof lines. *)
blanchet@36486
   461
      if is_only_type_information t then
blanchet@36486
   462
        map (replace_deps_in_line (num, [])) lines
blanchet@36486
   463
      (* Is there a repetition? If so, replace later line by earlier one. *)
blanchet@37323
   464
      else case take_prefix (aint_actual_inference t) lines of
blanchet@36486
   465
        (_, []) => lines (*no repetition of proof line*)
blanchet@36486
   466
      | (pre, Inference (num', _, _) :: post) =>
blanchet@36486
   467
        pre @ map (replace_deps_in_line (num', [num])) post
blanchet@36570
   468
    else if is_conjecture_clause_number conjecture_shape num then
blanchet@36486
   469
      Inference (num, t, []) :: lines
blanchet@36551
   470
    else
blanchet@36570
   471
      map (replace_deps_in_line (num, [])) lines
blanchet@36551
   472
  | add_line _ _ (Inference (num, t, deps)) lines =
blanchet@36486
   473
    (* Type information will be deleted later; skip repetition test. *)
blanchet@36486
   474
    if is_only_type_information t then
blanchet@36486
   475
      Inference (num, t, deps) :: lines
blanchet@36486
   476
    (* Is there a repetition? If so, replace later line by earlier one. *)
blanchet@37323
   477
    else case take_prefix (aint_actual_inference t) lines of
blanchet@36486
   478
      (* FIXME: Doesn't this code risk conflating proofs involving different
blanchet@36486
   479
         types?? *)
blanchet@36486
   480
       (_, []) => Inference (num, t, deps) :: lines
blanchet@36486
   481
     | (pre, Inference (num', t', _) :: post) =>
blanchet@36486
   482
       Inference (num, t', deps) ::
blanchet@36486
   483
       pre @ map (replace_deps_in_line (num', [num])) post
paulson@22044
   484
blanchet@36486
   485
(* Recursively delete empty lines (type information) from the proof. *)
blanchet@36486
   486
fun add_nontrivial_line (Inference (num, t, [])) lines =
blanchet@36486
   487
    if is_only_type_information t then delete_dep num lines
blanchet@36486
   488
    else Inference (num, t, []) :: lines
blanchet@36486
   489
  | add_nontrivial_line line lines = line :: lines
blanchet@36395
   490
and delete_dep num lines =
blanchet@36486
   491
  fold_rev add_nontrivial_line (map (replace_deps_in_line (num, [])) lines) []
blanchet@36486
   492
blanchet@37323
   493
(* ATPs sometimes reuse free variable names in the strangest ways. Removing
blanchet@37323
   494
   offending lines often does the trick. *)
blanchet@36560
   495
fun is_bad_free frees (Free x) = not (member (op =) frees x)
blanchet@36560
   496
  | is_bad_free _ _ = false
paulson@22470
   497
blanchet@36570
   498
(* Vampire is keen on producing these. *)
blanchet@36570
   499
fun is_trivial_formula (@{const Not} $ (Const (@{const_name "op ="}, _)
blanchet@36570
   500
                                        $ t1 $ t2)) = (t1 aconv t2)
blanchet@37498
   501
  | is_trivial_formula _ = false
blanchet@36570
   502
blanchet@37498
   503
fun add_desired_line _ _ _ _ (line as Definition (num, _, _)) (j, lines) =
blanchet@37323
   504
    (j, line :: map (replace_deps_in_line (num, [])) lines)
blanchet@37498
   505
  | add_desired_line isar_shrink_factor conjecture_shape thm_names frees
blanchet@36570
   506
                     (Inference (num, t, deps)) (j, lines) =
blanchet@36402
   507
    (j + 1,
blanchet@36570
   508
     if is_axiom_clause_number thm_names num orelse
blanchet@36570
   509
        is_conjecture_clause_number conjecture_shape num orelse
blanchet@36570
   510
        (not (is_only_type_information t) andalso
blanchet@36570
   511
         null (Term.add_tvars t []) andalso
blanchet@36570
   512
         not (exists_subterm (is_bad_free frees) t) andalso
blanchet@36570
   513
         not (is_trivial_formula t) andalso
blanchet@36570
   514
         (null lines orelse (* last line must be kept *)
blanchet@36924
   515
          (length deps >= 2 andalso j mod isar_shrink_factor = 0))) then
blanchet@36570
   516
       Inference (num, t, deps) :: lines  (* keep line *)
blanchet@36402
   517
     else
blanchet@36570
   518
       map (replace_deps_in_line (num, deps)) lines)  (* drop line *)
paulson@21978
   519
blanchet@36402
   520
(** EXTRACTING LEMMAS **)
paulson@21979
   521
blanchet@37991
   522
(* A list consisting of the first number in each line is returned. For TSTP,
blanchet@37991
   523
   interesting lines have the form "fof(108, axiom, ...)", where the number
blanchet@37991
   524
   (108) is extracted. For SPASS, lines have the form "108[0:Inp] ...", where
blanchet@37991
   525
   the first number (108) is extracted. *)
blanchet@37961
   526
fun extract_formula_numbers_in_atp_proof atp_proof =
blanchet@35865
   527
  let
blanchet@37962
   528
    val tokens_of = String.tokens (not o Char.isAlphaNum)
blanchet@37961
   529
    fun extract_num ("fof" :: num :: "axiom" :: _) = Int.fromString num
blanchet@36395
   530
      | extract_num (num :: "0" :: "Inp" :: _) = Int.fromString num
blanchet@36395
   531
      | extract_num _ = NONE
blanchet@36402
   532
  in atp_proof |> split_lines |> map_filter (extract_num o tokens_of) end
blanchet@37399
   533
blanchet@37399
   534
val indent_size = 2
blanchet@37399
   535
val no_label = ("", ~1)
blanchet@37399
   536
blanchet@37399
   537
val raw_prefix = "X"
blanchet@37399
   538
val assum_prefix = "A"
blanchet@37399
   539
val fact_prefix = "F"
blanchet@37399
   540
blanchet@37399
   541
fun string_for_label (s, num) = s ^ string_of_int num
blanchet@37399
   542
blanchet@37399
   543
fun metis_using [] = ""
blanchet@37399
   544
  | metis_using ls =
blanchet@37399
   545
    "using " ^ space_implode " " (map string_for_label ls) ^ " "
blanchet@37399
   546
fun metis_apply _ 1 = "by "
blanchet@37399
   547
  | metis_apply 1 _ = "apply "
blanchet@37399
   548
  | metis_apply i _ = "prefer " ^ string_of_int i ^ " apply "
blanchet@37479
   549
fun metis_name full_types = if full_types then "metisFT" else "metis"
blanchet@37479
   550
fun metis_call full_types [] = metis_name full_types
blanchet@37479
   551
  | metis_call full_types ss =
blanchet@37479
   552
    "(" ^ metis_name full_types ^ " " ^ space_implode " " ss ^ ")"
blanchet@37479
   553
fun metis_command full_types i n (ls, ss) =
blanchet@37479
   554
  metis_using ls ^ metis_apply i n ^ metis_call full_types ss
blanchet@37479
   555
fun metis_line full_types i n ss =
blanchet@36063
   556
  "Try this command: " ^
blanchet@37479
   557
  Markup.markup Markup.sendback (metis_command full_types i n ([], ss)) ^ ".\n"
blanchet@36281
   558
fun minimize_line _ [] = ""
blanchet@36281
   559
  | minimize_line minimize_command facts =
blanchet@36281
   560
    case minimize_command facts of
blanchet@36281
   561
      "" => ""
blanchet@36281
   562
    | command =>
blanchet@36065
   563
      "To minimize the number of lemmas, try this command: " ^
blanchet@36281
   564
      Markup.markup Markup.sendback command ^ ".\n"
immler@31840
   565
blanchet@37171
   566
val unprefix_chained = perhaps (try (unprefix chained_prefix))
blanchet@37171
   567
blanchet@37479
   568
fun metis_proof_text (full_types, minimize_command, atp_proof, thm_names, goal,
blanchet@37479
   569
                      i) =
blanchet@36063
   570
  let
blanchet@37171
   571
    val raw_lemmas =
blanchet@37961
   572
      atp_proof |> extract_formula_numbers_in_atp_proof
blanchet@36402
   573
                |> filter (is_axiom_clause_number thm_names)
blanchet@36402
   574
                |> map (fn i => Vector.sub (thm_names, i - 1))
blanchet@37171
   575
    val (chained_lemmas, other_lemmas) =
blanchet@37171
   576
      raw_lemmas |> List.partition (String.isPrefix chained_prefix)
blanchet@37171
   577
                 |>> map (unprefix chained_prefix)
blanchet@37171
   578
                 |> pairself (sort_distinct string_ord)
blanchet@37171
   579
    val lemmas = other_lemmas @ chained_lemmas
blanchet@36063
   580
    val n = Logic.count_prems (prop_of goal)
blanchet@37171
   581
  in
blanchet@37479
   582
    (metis_line full_types i n other_lemmas ^
blanchet@37479
   583
     minimize_line minimize_command lemmas, lemmas)
blanchet@37171
   584
  end
immler@31037
   585
blanchet@36486
   586
(** Isar proof construction and manipulation **)
blanchet@36486
   587
blanchet@36486
   588
fun merge_fact_sets (ls1, ss1) (ls2, ss2) =
blanchet@36486
   589
  (union (op =) ls1 ls2, union (op =) ss1 ss2)
blanchet@36402
   590
blanchet@36402
   591
type label = string * int
blanchet@36402
   592
type facts = label list * string list
blanchet@36402
   593
blanchet@36402
   594
datatype qualifier = Show | Then | Moreover | Ultimately
blanchet@36291
   595
blanchet@36402
   596
datatype step =
blanchet@36478
   597
  Fix of (string * typ) list |
blanchet@36486
   598
  Let of term * term |
blanchet@36402
   599
  Assume of label * term |
blanchet@36402
   600
  Have of qualifier list * label * term * byline
blanchet@36402
   601
and byline =
blanchet@36564
   602
  ByMetis of facts |
blanchet@36402
   603
  CaseSplit of step list list * facts
blanchet@36402
   604
blanchet@36574
   605
fun smart_case_split [] facts = ByMetis facts
blanchet@36574
   606
  | smart_case_split proofs facts = CaseSplit (proofs, facts)
blanchet@36574
   607
blanchet@36475
   608
fun add_fact_from_dep thm_names num =
blanchet@36475
   609
  if is_axiom_clause_number thm_names num then
blanchet@36480
   610
    apsnd (insert (op =) (Vector.sub (thm_names, num - 1)))
blanchet@36475
   611
  else
blanchet@36480
   612
    apfst (insert (op =) (raw_prefix, num))
blanchet@36402
   613
blanchet@37998
   614
fun forall_of v t = HOLogic.all_const (fastype_of v) $ lambda v t
blanchet@36491
   615
fun forall_vars t = fold_rev forall_of (map Var (Term.add_vars t [])) t
blanchet@36491
   616
blanchet@37498
   617
fun step_for_line _ _ (Definition (_, t1, t2)) = Let (t1, t2)
blanchet@36486
   618
  | step_for_line _ _ (Inference (num, t, [])) = Assume ((raw_prefix, num), t)
blanchet@36486
   619
  | step_for_line thm_names j (Inference (num, t, deps)) =
blanchet@36486
   620
    Have (if j = 1 then [Show] else [], (raw_prefix, num),
blanchet@36491
   621
          forall_vars t,
blanchet@36564
   622
          ByMetis (fold (add_fact_from_dep thm_names) deps ([], [])))
blanchet@36291
   623
blanchet@36967
   624
fun proof_from_atp_proof pool ctxt full_types tfrees isar_shrink_factor
blanchet@36967
   625
                         atp_proof conjecture_shape thm_names params frees =
blanchet@36402
   626
  let
blanchet@36486
   627
    val lines =
blanchet@37991
   628
      atp_proof ^ "$" (* the $ sign acts as a sentinel (FIXME: pick it up) *)
blanchet@36548
   629
      |> parse_proof pool
blanchet@36967
   630
      |> decode_lines ctxt full_types tfrees
blanchet@36551
   631
      |> rpair [] |-> fold_rev (add_line conjecture_shape thm_names)
blanchet@36486
   632
      |> rpair [] |-> fold_rev add_nontrivial_line
blanchet@37498
   633
      |> rpair (0, []) |-> fold_rev (add_desired_line isar_shrink_factor
blanchet@36570
   634
                                               conjecture_shape thm_names frees)
blanchet@36486
   635
      |> snd
blanchet@36402
   636
  in
blanchet@36909
   637
    (if null params then [] else [Fix params]) @
blanchet@36486
   638
    map2 (step_for_line thm_names) (length lines downto 1) lines
blanchet@36402
   639
  end
blanchet@36402
   640
blanchet@36402
   641
(* When redirecting proofs, we keep information about the labels seen so far in
blanchet@36402
   642
   the "backpatches" data structure. The first component indicates which facts
blanchet@36402
   643
   should be associated with forthcoming proof steps. The second component is a
blanchet@37322
   644
   pair ("assum_ls", "drop_ls"), where "assum_ls" are the labels that should
blanchet@37322
   645
   become assumptions and "drop_ls" are the labels that should be dropped in a
blanchet@37322
   646
   case split. *)
blanchet@36402
   647
type backpatches = (label * facts) list * (label list * label list)
blanchet@36402
   648
blanchet@36556
   649
fun used_labels_of_step (Have (_, _, _, by)) =
blanchet@36402
   650
    (case by of
blanchet@36564
   651
       ByMetis (ls, _) => ls
blanchet@36556
   652
     | CaseSplit (proofs, (ls, _)) =>
blanchet@36556
   653
       fold (union (op =) o used_labels_of) proofs ls)
blanchet@36556
   654
  | used_labels_of_step _ = []
blanchet@36556
   655
and used_labels_of proof = fold (union (op =) o used_labels_of_step) proof []
blanchet@36402
   656
blanchet@36402
   657
fun new_labels_of_step (Fix _) = []
blanchet@36486
   658
  | new_labels_of_step (Let _) = []
blanchet@36402
   659
  | new_labels_of_step (Assume (l, _)) = [l]
blanchet@36402
   660
  | new_labels_of_step (Have (_, l, _, _)) = [l]
blanchet@36402
   661
val new_labels_of = maps new_labels_of_step
blanchet@36402
   662
blanchet@36402
   663
val join_proofs =
blanchet@36402
   664
  let
blanchet@36402
   665
    fun aux _ [] = NONE
blanchet@36402
   666
      | aux proof_tail (proofs as (proof1 :: _)) =
blanchet@36402
   667
        if exists null proofs then
blanchet@36402
   668
          NONE
blanchet@36402
   669
        else if forall (curry (op =) (hd proof1) o hd) (tl proofs) then
blanchet@36402
   670
          aux (hd proof1 :: proof_tail) (map tl proofs)
blanchet@36402
   671
        else case hd proof1 of
blanchet@37498
   672
          Have ([], l, t, _) => (* FIXME: should we really ignore the "by"? *)
blanchet@36402
   673
          if forall (fn Have ([], l', t', _) :: _ => (l, t) = (l', t')
blanchet@36402
   674
                      | _ => false) (tl proofs) andalso
blanchet@36402
   675
             not (exists (member (op =) (maps new_labels_of proofs))
blanchet@36556
   676
                         (used_labels_of proof_tail)) then
blanchet@36402
   677
            SOME (l, t, map rev proofs, proof_tail)
blanchet@36402
   678
          else
blanchet@36402
   679
            NONE
blanchet@36402
   680
        | _ => NONE
blanchet@36402
   681
  in aux [] o map rev end
blanchet@36402
   682
blanchet@36402
   683
fun case_split_qualifiers proofs =
blanchet@36402
   684
  case length proofs of
blanchet@36402
   685
    0 => []
blanchet@36402
   686
  | 1 => [Then]
blanchet@36402
   687
  | _ => [Ultimately]
blanchet@36402
   688
blanchet@37991
   689
fun redirect_proof conjecture_shape hyp_ts concl_t proof =
wenzelm@33310
   690
  let
blanchet@37324
   691
    (* The first pass outputs those steps that are independent of the negated
blanchet@37324
   692
       conjecture. The second pass flips the proof by contradiction to obtain a
blanchet@37324
   693
       direct proof, introducing case splits when an inference depends on
blanchet@37324
   694
       several facts that depend on the negated conjecture. *)
blanchet@37324
   695
    fun find_hyp num = nth hyp_ts (index_in_shape num conjecture_shape)
blanchet@37996
   696
    val concl_l = (raw_prefix, List.last conjecture_shape)
blanchet@36402
   697
    fun first_pass ([], contra) = ([], contra)
blanchet@36491
   698
      | first_pass ((step as Fix _) :: proof, contra) =
blanchet@36491
   699
        first_pass (proof, contra) |>> cons step
blanchet@36491
   700
      | first_pass ((step as Let _) :: proof, contra) =
blanchet@36491
   701
        first_pass (proof, contra) |>> cons step
blanchet@37498
   702
      | first_pass ((step as Assume (l as (_, num), _)) :: proof, contra) =
blanchet@37996
   703
        if l = concl_l then
blanchet@37996
   704
          first_pass (proof, contra ||> l = concl_l ? cons step)
blanchet@36402
   705
        else
blanchet@36551
   706
          first_pass (proof, contra) |>> cons (Assume (l, find_hyp num))
blanchet@37324
   707
      | first_pass (Have (qs, l, t, ByMetis (ls, ss)) :: proof, contra) =
blanchet@37996
   708
        let val step = Have (qs, l, t, ByMetis (ls, ss)) in
blanchet@37324
   709
          if exists (member (op =) (fst contra)) ls then
blanchet@37324
   710
            first_pass (proof, contra |>> cons l ||> cons step)
blanchet@37324
   711
          else
blanchet@37324
   712
            first_pass (proof, contra) |>> cons step
blanchet@37324
   713
        end
blanchet@36402
   714
      | first_pass _ = raise Fail "malformed proof"
blanchet@36402
   715
    val (proof_top, (contra_ls, contra_proof)) =
blanchet@37996
   716
      first_pass (proof, ([concl_l], []))
blanchet@36402
   717
    val backpatch_label = the_default ([], []) oo AList.lookup (op =) o fst
blanchet@36402
   718
    fun backpatch_labels patches ls =
blanchet@36402
   719
      fold merge_fact_sets (map (backpatch_label patches) ls) ([], [])
blanchet@36402
   720
    fun second_pass end_qs ([], assums, patches) =
blanchet@37324
   721
        ([Have (end_qs, no_label, concl_t,
blanchet@36564
   722
                ByMetis (backpatch_labels patches (map snd assums)))], patches)
blanchet@36402
   723
      | second_pass end_qs (Assume (l, t) :: proof, assums, patches) =
blanchet@36402
   724
        second_pass end_qs (proof, (t, l) :: assums, patches)
blanchet@36564
   725
      | second_pass end_qs (Have (qs, l, t, ByMetis (ls, ss)) :: proof, assums,
blanchet@36402
   726
                            patches) =
blanchet@36402
   727
        if member (op =) (snd (snd patches)) l andalso
blanchet@37322
   728
           not (member (op =) (fst (snd patches)) l) andalso
blanchet@36402
   729
           not (AList.defined (op =) (fst patches) l) then
blanchet@36402
   730
          second_pass end_qs (proof, assums, patches ||> apsnd (append ls))
blanchet@36402
   731
        else
blanchet@36402
   732
          (case List.partition (member (op =) contra_ls) ls of
blanchet@36402
   733
             ([contra_l], co_ls) =>
blanchet@37322
   734
             if member (op =) qs Show then
blanchet@37322
   735
               second_pass end_qs (proof, assums,
blanchet@37322
   736
                                   patches |>> cons (contra_l, (co_ls, ss)))
blanchet@37322
   737
             else
blanchet@36402
   738
               second_pass end_qs
blanchet@36402
   739
                           (proof, assums,
blanchet@36402
   740
                            patches |>> cons (contra_l, (l :: co_ls, ss)))
blanchet@36402
   741
               |>> cons (if member (op =) (fst (snd patches)) l then
blanchet@37991
   742
                           Assume (l, negate_term t)
blanchet@36402
   743
                         else
blanchet@37991
   744
                           Have (qs, l, negate_term t,
blanchet@36564
   745
                                 ByMetis (backpatch_label patches l)))
blanchet@36402
   746
           | (contra_ls as _ :: _, co_ls) =>
blanchet@36402
   747
             let
blanchet@36402
   748
               val proofs =
blanchet@36402
   749
                 map_filter
blanchet@36402
   750
                     (fn l =>
blanchet@37996
   751
                         if l = concl_l then
blanchet@36402
   752
                           NONE
blanchet@36402
   753
                         else
blanchet@36402
   754
                           let
blanchet@36402
   755
                             val drop_ls = filter (curry (op <>) l) contra_ls
blanchet@36402
   756
                           in
blanchet@36402
   757
                             second_pass []
blanchet@36402
   758
                                 (proof, assums,
blanchet@36402
   759
                                  patches ||> apfst (insert (op =) l)
blanchet@36402
   760
                                          ||> apsnd (union (op =) drop_ls))
blanchet@36402
   761
                             |> fst |> SOME
blanchet@36402
   762
                           end) contra_ls
blanchet@37324
   763
               val (assumes, facts) =
blanchet@37324
   764
                 if member (op =) (fst (snd patches)) l then
blanchet@37991
   765
                   ([Assume (l, negate_term t)], (l :: co_ls, ss))
blanchet@37324
   766
                 else
blanchet@37324
   767
                   ([], (co_ls, ss))
blanchet@36402
   768
             in
blanchet@36402
   769
               (case join_proofs proofs of
blanchet@36402
   770
                  SOME (l, t, proofs, proof_tail) =>
blanchet@36402
   771
                  Have (case_split_qualifiers proofs @
blanchet@36402
   772
                        (if null proof_tail then end_qs else []), l, t,
blanchet@36574
   773
                        smart_case_split proofs facts) :: proof_tail
blanchet@36402
   774
                | NONE =>
blanchet@36402
   775
                  [Have (case_split_qualifiers proofs @ end_qs, no_label,
blanchet@36574
   776
                         concl_t, smart_case_split proofs facts)],
blanchet@36402
   777
                patches)
blanchet@37324
   778
               |>> append assumes
blanchet@36402
   779
             end
blanchet@36402
   780
           | _ => raise Fail "malformed proof")
blanchet@36402
   781
       | second_pass _ _ = raise Fail "malformed proof"
blanchet@36486
   782
    val proof_bottom =
blanchet@36486
   783
      second_pass [Show] (contra_proof, [], ([], ([], []))) |> fst
blanchet@36402
   784
  in proof_top @ proof_bottom end
blanchet@36402
   785
blanchet@36402
   786
val kill_duplicate_assumptions_in_proof =
blanchet@36402
   787
  let
blanchet@36402
   788
    fun relabel_facts subst =
blanchet@36402
   789
      apfst (map (fn l => AList.lookup (op =) subst l |> the_default l))
blanchet@36491
   790
    fun do_step (step as Assume (l, t)) (proof, subst, assums) =
blanchet@36402
   791
        (case AList.lookup (op aconv) assums t of
blanchet@36967
   792
           SOME l' => (proof, (l, l') :: subst, assums)
blanchet@36491
   793
         | NONE => (step :: proof, subst, (t, l) :: assums))
blanchet@36402
   794
      | do_step (Have (qs, l, t, by)) (proof, subst, assums) =
blanchet@36402
   795
        (Have (qs, l, t,
blanchet@36402
   796
               case by of
blanchet@36564
   797
                 ByMetis facts => ByMetis (relabel_facts subst facts)
blanchet@36402
   798
               | CaseSplit (proofs, facts) =>
blanchet@36402
   799
                 CaseSplit (map do_proof proofs, relabel_facts subst facts)) ::
blanchet@36402
   800
         proof, subst, assums)
blanchet@36491
   801
      | do_step step (proof, subst, assums) = (step :: proof, subst, assums)
blanchet@36402
   802
    and do_proof proof = fold do_step proof ([], [], []) |> #1 |> rev
blanchet@36402
   803
  in do_proof end
blanchet@36402
   804
blanchet@36402
   805
val then_chain_proof =
blanchet@36402
   806
  let
blanchet@36402
   807
    fun aux _ [] = []
blanchet@36491
   808
      | aux _ ((step as Assume (l, _)) :: proof) = step :: aux l proof
blanchet@36402
   809
      | aux l' (Have (qs, l, t, by) :: proof) =
blanchet@36402
   810
        (case by of
blanchet@36564
   811
           ByMetis (ls, ss) =>
blanchet@36402
   812
           Have (if member (op =) ls l' then
blanchet@36402
   813
                   (Then :: qs, l, t,
blanchet@36564
   814
                    ByMetis (filter_out (curry (op =) l') ls, ss))
blanchet@36402
   815
                 else
blanchet@36564
   816
                   (qs, l, t, ByMetis (ls, ss)))
blanchet@36402
   817
         | CaseSplit (proofs, facts) =>
blanchet@36402
   818
           Have (qs, l, t, CaseSplit (map (aux no_label) proofs, facts))) ::
blanchet@36402
   819
        aux l proof
blanchet@36491
   820
      | aux _ (step :: proof) = step :: aux no_label proof
blanchet@36402
   821
  in aux no_label end
blanchet@36402
   822
blanchet@36402
   823
fun kill_useless_labels_in_proof proof =
blanchet@36402
   824
  let
blanchet@36556
   825
    val used_ls = used_labels_of proof
blanchet@36402
   826
    fun do_label l = if member (op =) used_ls l then l else no_label
blanchet@36556
   827
    fun do_step (Assume (l, t)) = Assume (do_label l, t)
blanchet@36556
   828
      | do_step (Have (qs, l, t, by)) =
blanchet@36402
   829
        Have (qs, do_label l, t,
blanchet@36402
   830
              case by of
blanchet@36402
   831
                CaseSplit (proofs, facts) =>
blanchet@36556
   832
                CaseSplit (map (map do_step) proofs, facts)
blanchet@36402
   833
              | _ => by)
blanchet@36556
   834
      | do_step step = step
blanchet@36556
   835
  in map do_step proof end
blanchet@36402
   836
blanchet@36402
   837
fun prefix_for_depth n = replicate_string (n + 1)
blanchet@36402
   838
blanchet@36402
   839
val relabel_proof =
blanchet@36402
   840
  let
blanchet@36402
   841
    fun aux _ _ _ [] = []
blanchet@36402
   842
      | aux subst depth (next_assum, next_fact) (Assume (l, t) :: proof) =
blanchet@36402
   843
        if l = no_label then
blanchet@36402
   844
          Assume (l, t) :: aux subst depth (next_assum, next_fact) proof
blanchet@36402
   845
        else
blanchet@36402
   846
          let val l' = (prefix_for_depth depth assum_prefix, next_assum) in
blanchet@36402
   847
            Assume (l', t) ::
blanchet@36402
   848
            aux ((l, l') :: subst) depth (next_assum + 1, next_fact) proof
blanchet@36402
   849
          end
blanchet@36402
   850
      | aux subst depth (next_assum, next_fact) (Have (qs, l, t, by) :: proof) =
blanchet@36402
   851
        let
blanchet@36402
   852
          val (l', subst, next_fact) =
blanchet@36402
   853
            if l = no_label then
blanchet@36402
   854
              (l, subst, next_fact)
blanchet@36402
   855
            else
blanchet@36402
   856
              let
blanchet@36402
   857
                val l' = (prefix_for_depth depth fact_prefix, next_fact)
blanchet@36402
   858
              in (l', (l, l') :: subst, next_fact + 1) end
blanchet@36570
   859
          val relabel_facts =
blanchet@36570
   860
            apfst (map (fn l =>
blanchet@36570
   861
                           case AList.lookup (op =) subst l of
blanchet@36570
   862
                             SOME l' => l'
blanchet@36570
   863
                           | NONE => raise Fail ("unknown label " ^
blanchet@36570
   864
                                                 quote (string_for_label l))))
blanchet@36402
   865
          val by =
blanchet@36402
   866
            case by of
blanchet@36564
   867
              ByMetis facts => ByMetis (relabel_facts facts)
blanchet@36402
   868
            | CaseSplit (proofs, facts) =>
blanchet@36402
   869
              CaseSplit (map (aux subst (depth + 1) (1, 1)) proofs,
blanchet@36402
   870
                         relabel_facts facts)
blanchet@36402
   871
        in
blanchet@36402
   872
          Have (qs, l', t, by) ::
blanchet@36402
   873
          aux subst depth (next_assum, next_fact) proof
blanchet@36402
   874
        end
blanchet@36491
   875
      | aux subst depth nextp (step :: proof) =
blanchet@36491
   876
        step :: aux subst depth nextp proof
blanchet@36402
   877
  in aux [] 0 (1, 1) end
blanchet@36402
   878
blanchet@37479
   879
fun string_for_proof ctxt full_types i n =
blanchet@36402
   880
  let
blanchet@37319
   881
    fun fix_print_mode f x =
blanchet@37319
   882
      setmp_CRITICAL show_no_free_types true
blanchet@37319
   883
          (setmp_CRITICAL show_types true
blanchet@37319
   884
               (Print_Mode.setmp (filter (curry (op =) Symbol.xsymbolsN)
blanchet@37319
   885
                                         (print_mode_value ())) f)) x
blanchet@36402
   886
    fun do_indent ind = replicate_string (ind * indent_size) " "
blanchet@36478
   887
    fun do_free (s, T) =
blanchet@36478
   888
      maybe_quote s ^ " :: " ^
blanchet@36478
   889
      maybe_quote (fix_print_mode (Syntax.string_of_typ ctxt) T)
blanchet@36570
   890
    fun do_label l = if l = no_label then "" else string_for_label l ^ ": "
blanchet@36402
   891
    fun do_have qs =
blanchet@36402
   892
      (if member (op =) qs Moreover then "moreover " else "") ^
blanchet@36402
   893
      (if member (op =) qs Ultimately then "ultimately " else "") ^
blanchet@36402
   894
      (if member (op =) qs Then then
blanchet@36402
   895
         if member (op =) qs Show then "thus" else "hence"
blanchet@36402
   896
       else
blanchet@36402
   897
         if member (op =) qs Show then "show" else "have")
blanchet@36478
   898
    val do_term = maybe_quote o fix_print_mode (Syntax.string_of_term ctxt)
blanchet@36570
   899
    fun do_facts (ls, ss) =
blanchet@36570
   900
      let
blanchet@36570
   901
        val ls = ls |> sort_distinct (prod_ord string_ord int_ord)
blanchet@37171
   902
        val ss = ss |> map unprefix_chained |> sort_distinct string_ord
blanchet@37479
   903
      in metis_command full_types 1 1 (ls, ss) end
blanchet@36478
   904
    and do_step ind (Fix xs) =
blanchet@36478
   905
        do_indent ind ^ "fix " ^ space_implode " and " (map do_free xs) ^ "\n"
blanchet@36486
   906
      | do_step ind (Let (t1, t2)) =
blanchet@36486
   907
        do_indent ind ^ "let " ^ do_term t1 ^ " = " ^ do_term t2 ^ "\n"
blanchet@36402
   908
      | do_step ind (Assume (l, t)) =
blanchet@36402
   909
        do_indent ind ^ "assume " ^ do_label l ^ do_term t ^ "\n"
blanchet@36564
   910
      | do_step ind (Have (qs, l, t, ByMetis facts)) =
blanchet@36402
   911
        do_indent ind ^ do_have qs ^ " " ^
blanchet@36479
   912
        do_label l ^ do_term t ^ " " ^ do_facts facts ^ "\n"
blanchet@36402
   913
      | do_step ind (Have (qs, l, t, CaseSplit (proofs, facts))) =
blanchet@36402
   914
        space_implode (do_indent ind ^ "moreover\n")
blanchet@36402
   915
                      (map (do_block ind) proofs) ^
blanchet@36479
   916
        do_indent ind ^ do_have qs ^ " " ^ do_label l ^ do_term t ^ " " ^
blanchet@36478
   917
        do_facts facts ^ "\n"
blanchet@36402
   918
    and do_steps prefix suffix ind steps =
blanchet@36402
   919
      let val s = implode (map (do_step ind) steps) in
blanchet@36402
   920
        replicate_string (ind * indent_size - size prefix) " " ^ prefix ^
blanchet@36402
   921
        String.extract (s, ind * indent_size,
blanchet@36402
   922
                        SOME (size s - ind * indent_size - 1)) ^
blanchet@36402
   923
        suffix ^ "\n"
blanchet@36402
   924
      end
blanchet@36402
   925
    and do_block ind proof = do_steps "{ " " }" (ind + 1) proof
blanchet@36564
   926
    (* One-step proofs are pointless; better use the Metis one-liner
blanchet@36564
   927
       directly. *)
blanchet@36564
   928
    and do_proof [Have (_, _, _, ByMetis _)] = ""
blanchet@36564
   929
      | do_proof proof =
blanchet@36480
   930
        (if i <> 1 then "prefer " ^ string_of_int i ^ "\n" else "") ^
blanchet@36480
   931
        do_indent 0 ^ "proof -\n" ^
blanchet@36480
   932
        do_steps "" "" 1 proof ^
blanchet@36480
   933
        do_indent 0 ^ (if n <> 1 then "next" else "qed") ^ "\n"
blanchet@36488
   934
  in do_proof end
blanchet@36402
   935
blanchet@37479
   936
fun isar_proof_text (pool, debug, isar_shrink_factor, ctxt, conjecture_shape)
blanchet@37479
   937
                    (other_params as (full_types, _, atp_proof, thm_names, goal,
blanchet@37479
   938
                                      i)) =
blanchet@36402
   939
  let
blanchet@37995
   940
    (* ### FIXME: avoid duplication with ATP_Systems -- and move strip_subgoal
blanchet@37995
   941
       to ATP_Systems *)
blanchet@36909
   942
    val (params, hyp_ts, concl_t) = strip_subgoal goal i
blanchet@36909
   943
    val frees = fold Term.add_frees (concl_t :: hyp_ts) []
blanchet@36967
   944
    val tfrees = fold Term.add_tfrees (concl_t :: hyp_ts) []
blanchet@36402
   945
    val n = Logic.count_prems (prop_of goal)
blanchet@37479
   946
    val (one_line_proof, lemma_names) = metis_proof_text other_params
blanchet@36283
   947
    fun isar_proof_for () =
blanchet@36967
   948
      case proof_from_atp_proof pool ctxt full_types tfrees isar_shrink_factor
blanchet@36924
   949
                                atp_proof conjecture_shape thm_names params
blanchet@36924
   950
                                frees
blanchet@37991
   951
           |> redirect_proof conjecture_shape hyp_ts concl_t
blanchet@36402
   952
           |> kill_duplicate_assumptions_in_proof
blanchet@36402
   953
           |> then_chain_proof
blanchet@36402
   954
           |> kill_useless_labels_in_proof
blanchet@36402
   955
           |> relabel_proof
blanchet@37479
   956
           |> string_for_proof ctxt full_types i n of
blanchet@36283
   957
        "" => ""
blanchet@36402
   958
      | proof => "\nStructured proof:\n" ^ Markup.markup Markup.sendback proof
blanchet@35868
   959
    val isar_proof =
blanchet@36402
   960
      if debug then
blanchet@36283
   961
        isar_proof_for ()
blanchet@36283
   962
      else
blanchet@36283
   963
        try isar_proof_for ()
blanchet@36287
   964
        |> the_default "Warning: The Isar proof construction failed.\n"
blanchet@36283
   965
  in (one_line_proof ^ isar_proof, lemma_names) end
paulson@21978
   966
blanchet@36557
   967
fun proof_text isar_proof isar_params other_params =
blanchet@36557
   968
  (if isar_proof then isar_proof_text isar_params else metis_proof_text)
blanchet@36557
   969
      other_params
blanchet@36223
   970
immler@31038
   971
end;