--- a/src/HOL/Tools/Sledgehammer/sledgehammer_annotate.ML Tue Jun 25 17:13:09 2013 -0500
+++ b/src/HOL/Tools/Sledgehammer/sledgehammer_annotate.ML Wed Jun 26 18:24:41 2013 +0200
@@ -42,11 +42,31 @@
fun post_fold_term_type f s t =
post_traverse_term_type (fn t => fn T => fn s => (t, f t T s)) s t |> snd
-(* Data structures, orders *)
+fun fold_map_atypes f T s =
+ case T of
+ Type (name, Ts) =>
+ let val (Ts, s) = fold_map (fold_map_atypes f) Ts s in
+ (Type (name, Ts), s)
+ end
+ | _ => f T s
+
+(** get unique elements of a list **)
+local
+ fun unique' b x [] = if b then [x] else []
+ | unique' b x (y :: ys) =
+ if x = y then unique' false x ys
+ else unique' true y ys |> b ? cons x
+in
+ fun unique ord xs =
+ case sort ord xs of x :: ys => unique' true x ys | [] => []
+end
+
+(** Data structures, orders **)
+val indexname_ord = Term_Ord.fast_indexname_ord
val cost_ord = prod_ord int_ord (prod_ord int_ord int_ord)
structure Var_Set_Tab = Table(
type key = indexname list
- val ord = list_ord Term_Ord.fast_indexname_ord)
+ val ord = list_ord indexname_ord)
(* (1) Generalize types *)
fun generalize_types ctxt t =
@@ -59,10 +79,61 @@
t |> erase_types |> infer_types
end
-(* (2) Typing-spot table *)
+(* (2) match types *)
+fun match_types ctxt t1 t2 =
+ let
+ val thy = Proof_Context.theory_of ctxt
+ val get_types = post_fold_term_type (K cons) []
+ in
+ fold (Sign.typ_match thy) (get_types t1 ~~ get_types t2) Vartab.empty
+ end
+
+
+(* (3) handle trivial tfrees *)
+fun handle_trivial_tfrees ctxt (t', subst) =
+ let
+
+ val add_tfree_names =
+ snd #> snd #> fold_atyps (fn TFree (x, _) => cons x | _ => I)
+
+ val trivial_tfree_names =
+ Vartab.fold add_tfree_names subst []
+ |> filter_out (Variable.is_declared ctxt)
+ |> unique fast_string_ord
+ val tfree_name_trivial = Ord_List.member fast_string_ord trivial_tfree_names
+
+ val trivial_tvar_names =
+ Vartab.fold
+ (fn (tvar_name, (_, TFree (tfree_name, _))) =>
+ tfree_name_trivial tfree_name ? cons tvar_name
+ | _ => I)
+ subst
+ []
+ |> sort indexname_ord
+ val tvar_name_trivial = Ord_List.member indexname_ord trivial_tvar_names
+
+ val t' =
+ t' |> map_types
+ (map_type_tvar
+ (fn (idxn, sort) =>
+ if tvar_name_trivial idxn then dummyT else TVar (idxn, sort)))
+
+ val subst =
+ subst |> fold Vartab.delete trivial_tvar_names
+ |> Vartab.map
+ (K (apsnd (map_type_tfree
+ (fn (name, sort) =>
+ if tfree_name_trivial name then dummyT
+ else TFree (name, sort)))))
+ in
+ (t', subst)
+ end
+
+
+(* (4) Typing-spot table *)
local
fun key_of_atype (TVar (z, _)) =
- Ord_List.insert Term_Ord.fast_indexname_ord z
+ Ord_List.insert indexname_ord z
| key_of_atype _ = I
fun key_of_type T = fold_atyps key_of_atype T []
fun update_tab t T (tab, pos) =
@@ -83,7 +154,7 @@
post_fold_term_type update_tab (Var_Set_Tab.empty, 0) #> fst
end
-(* (3) Reverse-greedy *)
+(* (5) Reverse-greedy *)
fun reverse_greedy typing_spot_tab =
let
fun update_count z =
@@ -103,72 +174,43 @@
|>> sort_distinct (rev_order o cost_ord o pairself snd)
in fold drop_superfluous typing_spots ([], tvar_count_tab) |> fst end
-(* (4) Introduce annotations *)
-fun introduce_annotations ctxt spots t t' =
+(* (6) Introduce annotations *)
+fun introduce_annotations subst spots t t' =
let
- val thy = Proof_Context.theory_of ctxt
- val get_types = post_fold_term_type (K cons) []
- fun match_types tp =
- fold (Sign.typ_match thy) (op ~~ (pairself get_types tp)) Vartab.empty
- fun unica' b x [] = if b then [x] else []
- | unica' b x (y :: ys) =
- if x = y then unica' false x ys
- else unica' true y ys |> b ? cons x
- fun unica ord xs =
- case sort ord xs of x :: ys => unica' true x ys | [] => []
- val add_all_tfree_namesT = fold_atyps (fn TFree (x, _) => cons x | _ => I)
- fun erase_unica_tfrees env =
- let
- val unica =
- Vartab.fold (add_all_tfree_namesT o snd o snd) env []
- |> filter_out (Variable.is_declared ctxt)
- |> unica fast_string_ord
- val erase_unica = map_atyps
- (fn T as TFree (s, _) =>
- if Ord_List.member fast_string_ord unica s then dummyT else T
- | T => T)
- in Vartab.map (K (apsnd erase_unica)) env end
- val env = match_types (t', t) |> erase_unica_tfrees
- fun get_annot env (TFree _) = (false, (env, dummyT))
- | get_annot env (T as TVar (v, S)) =
- let val T' = Envir.subst_type env T in
- if T' = dummyT then (false, (env, dummyT))
- else (true, (Vartab.update (v, (S, dummyT)) env, T'))
- end
- | get_annot env (Type (S, Ts)) =
- (case fold_rev (fn T => fn (b, (env, Ts)) =>
- let
- val (b', (env', T)) = get_annot env T
- in (b orelse b', (env', T :: Ts)) end)
- Ts (false, (env, [])) of
- (true, (env', Ts)) => (true, (env', Type (S, Ts)))
- | (false, (env', _)) => (false, (env', dummyT)))
- fun post1 _ T (env, cp, ps as p :: ps', annots) =
+ fun subst_atype (T as TVar (idxn, S)) subst =
+ (Envir.subst_type subst T,
+ Vartab.update (idxn, (S, dummyT)) subst)
+ | subst_atype T subst = (T, subst)
+ val subst_type = fold_map_atypes subst_atype
+ fun collect_annot _ T (subst, cp, ps as p :: ps', annots) =
if p <> cp then
- (env, cp + 1, ps, annots)
+ (subst, cp + 1, ps, annots)
else
- let val (annot_necessary, (env', T')) = get_annot env T in
- (env', cp + 1, ps', annots |> annot_necessary ? cons (p, T'))
+ let val (T, subst) = subst_type T subst in
+ (subst, cp + 1, ps', (p, T)::annots)
end
- | post1 _ _ accum = accum
- val (_, _, _, annots) = post_fold_term_type post1 (env, 0, spots, []) t'
- fun post2 t _ (cp, annots as (p, T) :: annots') =
+ | collect_annot _ _ x = x
+ val (_, _, _, annots) =
+ post_fold_term_type collect_annot (subst, 0, spots, []) t'
+ fun insert_annot t _ (cp, annots as (p, T) :: annots') =
if p <> cp then (t, (cp + 1, annots))
else (Type.constraint T t, (cp + 1, annots'))
- | post2 t _ x = (t, x)
+ | insert_annot t _ x = (t, x)
in
- t |> post_traverse_term_type post2 (0, rev annots)
+ t |> post_traverse_term_type insert_annot (0, rev annots)
|> fst
end
-(* (5) Annotate *)
+(* (7) Annotate *)
fun annotate_types ctxt t =
let
val t' = generalize_types ctxt t
+ val subst = match_types ctxt t' t
+ val (t', subst) = (t', subst) |> handle_trivial_tfrees ctxt
val typing_spots =
t' |> typing_spot_table
|> reverse_greedy
|> sort int_ord
- in introduce_annotations ctxt typing_spots t t' end
+ in introduce_annotations subst typing_spots t t' end
end