diff -r f732e6f3bf7f -r aff193f53a64 src/HOL/Library/Mapping.thy --- a/src/HOL/Library/Mapping.thy Wed Apr 09 14:08:18 2014 +0200 +++ b/src/HOL/Library/Mapping.thy Wed Apr 09 14:08:25 2014 +0200 @@ -10,25 +10,29 @@ subsection {* Parametricity transfer rules *} +lemma map_of_foldr: -- {* FIXME move *} + "map_of xs = foldr (\(k, v) m. m(k \ v)) xs Map.empty" + using map_add_map_of_foldr [of Map.empty] by auto + context begin interpretation lifting_syntax . -lemma empty_transfer: +lemma empty_parametric: "(A ===> rel_option B) Map.empty Map.empty" by transfer_prover -lemma lookup_transfer: "((A ===> B) ===> A ===> B) (\m k. m k) (\m k. m k)" +lemma lookup_parametric: "((A ===> B) ===> A ===> B) (\m k. m k) (\m k. m k)" by transfer_prover -lemma update_transfer: +lemma update_parametric: assumes [transfer_rule]: "bi_unique A" shows "(A ===> B ===> (A ===> rel_option B) ===> A ===> rel_option B) (\k v m. m(k \ v)) (\k v m. m(k \ v))" by transfer_prover -lemma delete_transfer: +lemma delete_parametric: assumes [transfer_rule]: "bi_unique A" shows "(A ===> (A ===> rel_option B) ===> A ===> rel_option B) (\k m. m(k := None)) (\k m. m(k := None))" @@ -38,23 +42,31 @@ "(rel_option A ===> HOL.eq) Option.is_none Option.is_none" by (auto simp add: is_none_def rel_fun_def rel_option_iff split: option.split) -lemma dom_transfer: +lemma dom_parametric: assumes [transfer_rule]: "bi_total A" shows "((A ===> rel_option B) ===> rel_set A) dom dom" unfolding dom_def [abs_def] is_none_def [symmetric] by transfer_prover -lemma map_of_transfer [transfer_rule]: +lemma map_of_parametric [transfer_rule]: assumes [transfer_rule]: "bi_unique R1" shows "(list_all2 (rel_prod R1 R2) ===> R1 ===> rel_option R2) map_of map_of" unfolding map_of_def by transfer_prover -lemma tabulate_transfer: +lemma map_entry_parametric [transfer_rule]: + assumes [transfer_rule]: "bi_unique A" + shows "(A ===> (B ===> B) ===> (A ===> rel_option B) ===> A ===> rel_option B) + (\k f m. (case m k of None \ m + | Some v \ m (k \ (f v)))) (\k f m. (case m k of None \ m + | Some v \ m (k \ (f v))))" + by transfer_prover + +lemma tabulate_parametric: assumes [transfer_rule]: "bi_unique A" shows "(list_all2 A ===> (A ===> B) ===> A ===> rel_option B) (\ks f. (map_of (map (\k. (k, f k)) ks))) (\ks f. (map_of (map (\k. (k, f k)) ks)))" by transfer_prover -lemma bulkload_transfer: +lemma bulkload_parametric: "(list_all2 A ===> HOL.eq ===> rel_option A) (\xs k. if k < length xs then Some (xs ! k) else None) (\xs k. if k < length xs then Some (xs ! k) else None)" proof @@ -72,20 +84,13 @@ done qed -lemma map_transfer: +lemma map_parametric: "((A ===> B) ===> (C ===> D) ===> (B ===> rel_option C) ===> A ===> rel_option D) (\f g m. (map_option g \ m \ f)) (\f g m. (map_option g \ m \ f))" by transfer_prover -lemma map_entry_transfer: - assumes [transfer_rule]: "bi_unique A" - shows "(A ===> (B ===> B) ===> (A ===> rel_option B) ===> A ===> rel_option B) - (\k f m. (case m k of None \ m - | Some v \ m (k \ (f v)))) (\k f m. (case m k of None \ m - | Some v \ m (k \ (f v))))" - by transfer_prover +end -end subsection {* Type definition and primitive operations *} @@ -96,28 +101,28 @@ setup_lifting (no_code) type_definition_mapping lift_definition empty :: "('a, 'b) mapping" - is Map.empty parametric empty_transfer . + is Map.empty parametric empty_parametric . lift_definition lookup :: "('a, 'b) mapping \ 'a \ 'b option" - is "\m k. m k" parametric lookup_transfer . + is "\m k. m k" parametric lookup_parametric . lift_definition update :: "'a \ 'b \ ('a, 'b) mapping \ ('a, 'b) mapping" - is "\k v m. m(k \ v)" parametric update_transfer . + is "\k v m. m(k \ v)" parametric update_parametric . lift_definition delete :: "'a \ ('a, 'b) mapping \ ('a, 'b) mapping" - is "\k m. m(k := None)" parametric delete_transfer . + is "\k m. m(k := None)" parametric delete_parametric . lift_definition keys :: "('a, 'b) mapping \ 'a set" - is dom parametric dom_transfer . + is dom parametric dom_parametric . lift_definition tabulate :: "'a list \ ('a \ 'b) \ ('a, 'b) mapping" - is "\ks f. (map_of (List.map (\k. (k, f k)) ks))" parametric tabulate_transfer . + is "\ks f. (map_of (List.map (\k. (k, f k)) ks))" parametric tabulate_parametric . lift_definition bulkload :: "'a list \ (nat, 'a) mapping" - is "\xs k. if k < length xs then Some (xs ! k) else None" parametric bulkload_transfer . + is "\xs k. if k < length xs then Some (xs ! k) else None" parametric bulkload_parametric . lift_definition map :: "('c \ 'a) \ ('b \ 'd) \ ('a, 'b) mapping \ ('c, 'd) mapping" - is "\f g m. (map_option g \ m \ f)" parametric map_transfer . + is "\f g m. (map_option g \ m \ f)" parametric map_parametric . subsection {* Functorial structure *} @@ -148,11 +153,14 @@ where "default k v m = (if k \ keys m then m else update k v m)" +text {* Manual derivation of transfer rule is non-trivial *} + lift_definition map_entry :: "'a \ ('b \ 'b) \ ('a, 'b) mapping \ ('a, 'b) mapping" is "\k f m. (case m k of None \ m - | Some v \ m (k \ (f v)))" parametric map_entry_transfer . + | Some v \ m (k \ (f v)))" parametric map_entry_parametric . -lemma map_entry_code [code]: "map_entry k f m = (case lookup m k of None \ m +lemma map_entry_code [code]: + "map_entry k f m = (case lookup m k of None \ m | Some v \ update k (f v) m)" by transfer rule @@ -160,12 +168,9 @@ where "map_default k v f m = map_entry k f (default k v m)" -lift_definition of_alist :: "('k \ 'v) list \ ('k, 'v) mapping" - is map_of parametric map_of_transfer . - -lemma of_alist_code [code]: +definition of_alist :: "('k \ 'v) list \ ('k, 'v) mapping" +where "of_alist xs = foldr (\(k, v) m. update k v m) xs empty" - by transfer (simp add: map_add_map_of_foldr [symmetric]) instantiation mapping :: (type, type) equal begin @@ -189,6 +194,11 @@ shows "(pcr_mapping A B ===> pcr_mapping A B ===> op=) HOL.eq HOL.equal" by (unfold equal) transfer_prover +lemma of_alist_transfer [transfer_rule]: + assumes [transfer_rule]: "bi_unique R1" + shows "(list_all2 (rel_prod R1 R2) ===> pcr_mapping R1 R2) map_of of_alist" + unfolding of_alist_def [abs_def] map_of_foldr [abs_def] by transfer_prover + end @@ -380,12 +390,8 @@ "tabulate xs f = fold (\k m. update k (f k) m) xs empty" proof transfer fix f :: "'a \ 'b" and xs - from map_add_map_of_foldr - have "Map.empty ++ map_of (List.map (\k. (k, f k)) xs) = - foldr (\(k, v) m. m(k \ v)) (List.map (\k. (k, f k)) xs) Map.empty" - . - then have "map_of (List.map (\k. (k, f k)) xs) = foldr (\k m. m(k \ f k)) xs Map.empty" - by (simp add: foldr_map comp_def) + have "map_of (List.map (\k. (k, f k)) xs) = foldr (\k m. m(k \ f k)) xs Map.empty" + by (simp add: foldr_map comp_def map_of_foldr) also have "foldr (\k m. m(k \ f k)) xs = fold (\k m. m(k \ f k)) xs" by (rule foldr_fold) (simp add: fun_eq_iff) ultimately show "map_of (List.map (\k. (k, f k)) xs) = fold (\k m. m(k \ f k)) xs Map.empty"