(* Title: Pure/Isar/find_theorems.ML
ID: $Id$
Author: Rafal Kolanski, NICTA and Tobias Nipkow, TU Muenchen
Retrieve theorems from proof context.
*)
val thms_containing_limit = ref 40;
signature FIND_THEOREMS =
sig
val find_thms: Proof.context -> FactIndex.spec -> (thmref * thm) list
datatype 'term criterion =
Name of string | Intro | Elim | Dest | Simp of 'term | Pattern of 'term
val print_theorems: Proof.context -> term option -> int option ->
(bool * string criterion) list -> unit
end;
structure FindTheorems: FIND_THEOREMS =
struct
(* find_thms *)
fun find_thms ctxt spec =
(PureThy.thms_containing (ProofContext.theory_of ctxt) spec @
ProofContext.lthms_containing ctxt spec)
|> map PureThy.selections |> List.concat;
(* matching theorems *)
local
(*returns all those facts whose subterm extracted by extract can be
instantiated to obj; the list is sorted according to the number of premises
and the size of the required substitution*)
fun select_match (extract_thms, extract_term) ctxt obj facts =
let
val match = #2 o Pattern.match (Sign.tsig_of (ProofContext.sign_of ctxt));
fun match_size pat =
let val subst = match (pat, obj) (*exception Pattern.MATCH*)
in SOME (Vartab.foldl (op + o apsnd (Term.size_of_term o #2 o #2)) (0, subst)) end
handle Pattern.MATCH => NONE;
fun select (fact as (_, thm)) =
let
fun first_match (th :: ths) res =
(case match_size (extract_term (Thm.prop_of th)) of
SOME s => ((Thm.nprems_of th, s), fact) :: res
| NONE => first_match ths res)
| first_match [] res = res;
in first_match (extract_thms thm) end;
fun thm_ord (((p0, s0), _), ((p1, s1), _)) =
prod_ord (int_ord o pairself (fn 0 => 0 | x => 1)) int_ord ((p0, s0), (p1, s1));
in
fold select facts []
|> Library.sort thm_ord |> map #2
end;
in
fun is_matching_thm extract ctxt prop fact =
not (null (select_match extract ctxt prop [fact]));
end;
(** search criteria **)
datatype 'term criterion =
Name of string | Intro | Elim | Dest | Simp of 'term | Pattern of 'term;
fun read_criterion _ (Name name) = Name name
| read_criterion _ Intro = Intro
| read_criterion _ Elim = Elim
| read_criterion _ Dest = Dest
| read_criterion ctxt (Simp str) = Simp (ProofContext.read_term ctxt str)
| read_criterion ctxt (Pattern str) =
Pattern (hd (ProofContext.read_term_pats TypeInfer.logicT ctxt [str]));
fun pretty_criterion ctxt (b, c) =
let
fun prfx s = if b then s else "-" ^ s;
in
(case c of
Name name => Pretty.str (prfx "name: " ^ quote name)
| Intro => Pretty.str (prfx "intro")
| Elim => Pretty.str (prfx "elim")
| Dest => Pretty.str (prfx "dest")
| Simp t => Pretty.block [Pretty.str (prfx "simp:"), Pretty.brk 1,
Pretty.quote (ProofContext.pretty_term ctxt t)]
| Pattern pat => Pretty.enclose (prfx " \"") "\""
[ProofContext.pretty_term ctxt (Term.show_dummy_patterns pat)])
end;
(** search criterion filters **)
(* filter_name *)
fun is_substring pat str =
if String.size pat = 0 then true
else if String.size pat > String.size str then false
else if String.substring (str, 0, String.size pat) = pat then true
else is_substring pat (String.extract (str, 1, NONE));
(*filter that just looks for a string in the name,
substring match only (no regexps are performed)*)
fun filter_name str_pat ((name, _), _) = is_substring str_pat name;
(* filter intro/elim/dest rules *)
local
(*elimination rule: conclusion is a Var which does not appear in the major premise*)
fun is_elim ctxt thm =
let
val sg = ProofContext.sign_of ctxt;
val prop = Thm.prop_of thm;
val concl = ObjectLogic.drop_judgment sg (Logic.strip_imp_concl prop);
val major_prem = Library.take (1, Logic.strip_imp_prems prop);
val prem_vars = Drule.vars_of_terms major_prem;
in
not (null major_prem) andalso
Term.is_Var concl andalso
not (Term.dest_Var concl mem prem_vars)
end;
fun filter_elim_dest check_thm ctxt goal =
let
val extract_elim =
(fn thm => if Thm.no_prems thm then [] else [thm],
hd o Logic.strip_imp_prems);
val prems = Logic.prems_of_goal goal 1;
in
fn fact => prems |> List.exists (fn prem =>
is_matching_thm extract_elim ctxt prem fact
andalso (check_thm ctxt) (#2 fact))
end;
in
fun filter_intro ctxt goal =
let
val extract_intro = (single, Logic.strip_imp_concl);
val concl = Logic.concl_of_goal goal 1;
in
fn fact => is_matching_thm extract_intro ctxt concl fact
andalso not (is_elim ctxt (#2 fact))
end;
fun filter_elim ctxt = filter_elim_dest is_elim ctxt;
fun filter_dest ctxt = filter_elim_dest (not oo is_elim) ctxt;
end;
(* filter_simp *)
fun filter_simp ctxt t =
let
val (_, {mk_rews = {mk, ...}, ...}) =
MetaSimplifier.rep_ss (Simplifier.local_simpset_of ctxt);
val extract_simp = (mk, #1 o Logic.dest_equals o Logic.strip_imp_concl);
in is_matching_thm extract_simp ctxt t end;
(* filter_pattern *)
fun filter_pattern ctxt pat =
let val tsig = Sign.tsig_of (ProofContext.sign_of ctxt)
in fn (_, thm) => Pattern.matches_subterm tsig (pat, Thm.prop_of thm) end;
(* interpret criteria as filters *)
local
fun err_no_goal c =
error ("Current goal required for " ^ c ^ " search criterion");
fun filter_crit _ _ (Name name) = filter_name name
| filter_crit _ NONE Intro = err_no_goal "intro"
| filter_crit _ NONE Elim = err_no_goal "elim"
| filter_crit _ NONE Dest = err_no_goal "dest"
| filter_crit ctxt (SOME goal) Intro = filter_intro ctxt goal
| filter_crit ctxt (SOME goal) Elim = filter_elim ctxt goal
| filter_crit ctxt (SOME goal) Dest = filter_dest ctxt goal
| filter_crit ctxt _ (Simp str) = filter_simp ctxt str
| filter_crit ctxt _ (Pattern str) = filter_pattern ctxt str;
in
fun filter_criterion ctxt opt_goal (b, c) =
(if b then I else not) o filter_crit ctxt opt_goal c;
fun all_filters filters = List.filter (fn x => List.all (fn f => f x) filters);
end;
(* print_theorems *)
fun print_theorems ctxt opt_goal opt_limit raw_criteria =
let
val criteria = map (apsnd (read_criterion ctxt)) raw_criteria;
val filters = map (filter_criterion ctxt opt_goal) criteria;
val matches = all_filters filters (find_thms ctxt ([], []));
val len = length matches;
val limit = if_none opt_limit (! thms_containing_limit);
fun prt_fact (thmref, thm) =
ProofContext.pretty_fact ctxt (PureThy.string_of_thmref thmref, [thm]);
in
Pretty.big_list "searched for:" (map (pretty_criterion ctxt) criteria) :: Pretty.str "" ::
(if null matches then [Pretty.str "nothing found"]
else
[Pretty.str ("found " ^ string_of_int len ^ " theorems" ^
(if len <= limit then "" else " (" ^ string_of_int limit ^ " displayed)") ^ ":"),
Pretty.str ""] @
map prt_fact (Library.drop (len - limit, matches)))
|> Pretty.chunks |> Pretty.writeln
end;
end;