--- a/src/HOL/List.thy Sun Feb 12 22:05:02 2023 +0100
+++ b/src/HOL/List.thy Mon Feb 13 16:07:41 2023 +0100
@@ -243,6 +243,11 @@
abbreviation length :: "'a list \<Rightarrow> nat" where
"length \<equiv> size"
+primrec map_of :: "('a \<times> 'b) list \<Rightarrow> 'a \<Rightarrow> 'b option"
+where
+ "map_of [] = (\<lambda>x. None)"
+| "map_of (p # ps) = (map_of ps)(fst p := Some(snd p))"
+
definition enumerate :: "nat \<Rightarrow> 'a list \<Rightarrow> (nat \<times> 'a) list" where
enumerate_eq_zip: "enumerate n xs = zip [n..<n + length xs] xs"
@@ -4681,6 +4686,126 @@
by (subst foldr_fold [symmetric]) simp_all
+subsubsection \<open>\<^const>\<open>map_of\<close>\<close>
+
+lemma map_of_eq_None_iff:
+ "(map_of xys x = None) = (x \<notin> fst ` (set xys))"
+by (induct xys) simp_all
+
+lemma map_of_eq_Some_iff [simp]:
+ "distinct(map fst xys) \<Longrightarrow> (map_of xys x = Some y) = ((x,y) \<in> set xys)"
+proof (induct xys)
+ case (Cons xy xys)
+ then show ?case
+ by (cases xy) (auto simp flip: map_of_eq_None_iff)
+qed auto
+
+lemma Some_eq_map_of_iff [simp]:
+ "distinct(map fst xys) \<Longrightarrow> (Some y = map_of xys x) = ((x,y) \<in> set xys)"
+by (auto simp del: map_of_eq_Some_iff simp: map_of_eq_Some_iff [symmetric])
+
+lemma map_of_is_SomeI [simp]:
+ "\<lbrakk>distinct(map fst xys); (x,y) \<in> set xys\<rbrakk> \<Longrightarrow> map_of xys x = Some y"
+ by simp
+
+lemma map_of_zip_is_None [simp]:
+ "length xs = length ys \<Longrightarrow> (map_of (zip xs ys) x = None) = (x \<notin> set xs)"
+by (induct rule: list_induct2) simp_all
+
+lemma map_of_zip_is_Some:
+ assumes "length xs = length ys"
+ shows "x \<in> set xs \<longleftrightarrow> (\<exists>y. map_of (zip xs ys) x = Some y)"
+using assms by (induct rule: list_induct2) simp_all
+
+lemma map_of_zip_upd:
+ fixes x :: 'a and xs :: "'a list" and ys zs :: "'b list"
+ assumes "length ys = length xs"
+ and "length zs = length xs"
+ and "x \<notin> set xs"
+ and "(map_of (zip xs ys))(x := Some y) = (map_of (zip xs zs))(x := Some z)"
+ shows "map_of (zip xs ys) = map_of (zip xs zs)"
+proof
+ fix x' :: 'a
+ show "map_of (zip xs ys) x' = map_of (zip xs zs) x'"
+ proof (cases "x = x'")
+ case True
+ from assms True map_of_zip_is_None [of xs ys x']
+ have "map_of (zip xs ys) x' = None" by simp
+ moreover from assms True map_of_zip_is_None [of xs zs x']
+ have "map_of (zip xs zs) x' = None" by simp
+ ultimately show ?thesis by simp
+ next
+ case False from assms
+ have "((map_of (zip xs ys))(x := Some y)) x' = ((map_of (zip xs zs))(x := Some z)) x'" by auto
+ with False show ?thesis by simp
+ qed
+qed
+
+lemma map_of_zip_inject:
+ assumes "length ys = length xs"
+ and "length zs = length xs"
+ and dist: "distinct xs"
+ and map_of: "map_of (zip xs ys) = map_of (zip xs zs)"
+ shows "ys = zs"
+ using assms(1) assms(2)[symmetric]
+ using dist map_of
+proof (induct ys xs zs rule: list_induct3)
+ case Nil show ?case by simp
+next
+ case (Cons y ys x xs z zs)
+ from \<open>map_of (zip (x#xs) (y#ys)) = map_of (zip (x#xs) (z#zs))\<close>
+ have map_of: "(map_of (zip xs ys))(x := Some y) = (map_of (zip xs zs))(x := Some z)" by simp
+ from Cons have "length ys = length xs" and "length zs = length xs"
+ and "x \<notin> set xs" by simp_all
+ then have "map_of (zip xs ys) = map_of (zip xs zs)" using map_of by (rule map_of_zip_upd)
+ with Cons.hyps \<open>distinct (x # xs)\<close> have "ys = zs" by simp
+ moreover have "y = z" using fun_upd_eqD[OF map_of] by simp
+ ultimately show ?case by simp
+qed
+
+lemma map_of_zip_nth:
+ assumes "length xs = length ys"
+ assumes "distinct xs"
+ assumes "i < length ys"
+ shows "map_of (zip xs ys) (xs ! i) = Some (ys ! i)"
+using assms proof (induct arbitrary: i rule: list_induct2)
+ case Nil
+ then show ?case by simp
+next
+ case (Cons x xs y ys)
+ then show ?case
+ using less_Suc_eq_0_disj by auto
+qed
+
+lemma map_of_zip_map:
+ "map_of (zip xs (map f xs)) = (\<lambda>x. if x \<in> set xs then Some (f x) else None)"
+ by (induct xs) (simp_all add: fun_eq_iff)
+
+lemma map_of_SomeD: "map_of xs k = Some y \<Longrightarrow> (k, y) \<in> set xs"
+ by (induct xs) (auto split: if_splits)
+
+lemma map_of_mapk_SomeI:
+ "inj f \<Longrightarrow> map_of t k = Some x \<Longrightarrow>
+ map_of (map (case_prod (\<lambda>k. Pair (f k))) t) (f k) = Some x"
+by (induct t) (auto simp: inj_eq)
+
+lemma weak_map_of_SomeI: "(k, x) \<in> set l \<Longrightarrow> \<exists>x. map_of l k = Some x"
+by (induct l) auto
+
+lemma map_of_filter_in:
+ "map_of xs k = Some z \<Longrightarrow> P k z \<Longrightarrow> map_of (filter (case_prod P) xs) k = Some z"
+by (induct xs) auto
+
+lemma map_of_map:
+ "map_of (map (\<lambda>(k, v). (k, f v)) xs) = map_option f \<circ> map_of xs"
+ by (induct xs) (auto simp: fun_eq_iff)
+
+lemma map_of_Cons_code [code]:
+ "map_of [] k = None"
+ "map_of ((l, v) # ps) k = (if l = k then Some v else map_of ps k)"
+ by simp_all
+
+
subsubsection \<open>\<^const>\<open>enumerate\<close>\<close>
lemma enumerate_simps [simp, code]:
--- a/src/HOL/Map.thy Sun Feb 12 22:05:02 2023 +0100
+++ b/src/HOL/Map.thy Mon Feb 13 16:07:41 2023 +0100
@@ -70,21 +70,11 @@
"_Map (_Maplets ms1 ms2)" \<leftharpoondown> "_MapUpd (_Map ms1) ms2"
"_Maplets ms1 (_Maplets ms2 ms3)" \<leftharpoondown> "_Maplets (_Maplets ms1 ms2) ms3"
-primrec map_of :: "('a \<times> 'b) list \<Rightarrow> 'a \<rightharpoonup> 'b"
-where
- "map_of [] = empty"
-| "map_of (p # ps) = (map_of ps)(fst p \<mapsto> snd p)"
-
definition map_upds :: "('a \<rightharpoonup> 'b) \<Rightarrow> 'a list \<Rightarrow> 'b list \<Rightarrow> 'a \<rightharpoonup> 'b"
where "map_upds m xs ys = m ++ map_of (rev (zip xs ys))"
translations
"_MapUpd m (_maplets x y)" \<rightleftharpoons> "CONST map_upds m x y"
-lemma map_of_Cons_code [code]:
- "map_of [] k = None"
- "map_of ((l, v) # ps) k = (if l = k then Some v else map_of ps k)"
- by simp_all
-
subsection \<open>@{term [source] empty}\<close>
@@ -142,99 +132,6 @@
"empty = map_of xys \<longleftrightarrow> xys = []"
by(subst eq_commute) simp
-lemma map_of_eq_None_iff:
- "(map_of xys x = None) = (x \<notin> fst ` (set xys))"
-by (induct xys) simp_all
-
-lemma map_of_eq_Some_iff [simp]:
- "distinct(map fst xys) \<Longrightarrow> (map_of xys x = Some y) = ((x,y) \<in> set xys)"
-proof (induct xys)
- case (Cons xy xys)
- then show ?case
- by (cases xy) (auto simp flip: map_of_eq_None_iff)
-qed auto
-
-lemma Some_eq_map_of_iff [simp]:
- "distinct(map fst xys) \<Longrightarrow> (Some y = map_of xys x) = ((x,y) \<in> set xys)"
-by (auto simp del: map_of_eq_Some_iff simp: map_of_eq_Some_iff [symmetric])
-
-lemma map_of_is_SomeI [simp]:
- "\<lbrakk>distinct(map fst xys); (x,y) \<in> set xys\<rbrakk> \<Longrightarrow> map_of xys x = Some y"
- by simp
-
-lemma map_of_zip_is_None [simp]:
- "length xs = length ys \<Longrightarrow> (map_of (zip xs ys) x = None) = (x \<notin> set xs)"
-by (induct rule: list_induct2) simp_all
-
-lemma map_of_zip_is_Some:
- assumes "length xs = length ys"
- shows "x \<in> set xs \<longleftrightarrow> (\<exists>y. map_of (zip xs ys) x = Some y)"
-using assms by (induct rule: list_induct2) simp_all
-
-lemma map_of_zip_upd:
- fixes x :: 'a and xs :: "'a list" and ys zs :: "'b list"
- assumes "length ys = length xs"
- and "length zs = length xs"
- and "x \<notin> set xs"
- and "map_of (zip xs ys)(x \<mapsto> y) = map_of (zip xs zs)(x \<mapsto> z)"
- shows "map_of (zip xs ys) = map_of (zip xs zs)"
-proof
- fix x' :: 'a
- show "map_of (zip xs ys) x' = map_of (zip xs zs) x'"
- proof (cases "x = x'")
- case True
- from assms True map_of_zip_is_None [of xs ys x']
- have "map_of (zip xs ys) x' = None" by simp
- moreover from assms True map_of_zip_is_None [of xs zs x']
- have "map_of (zip xs zs) x' = None" by simp
- ultimately show ?thesis by simp
- next
- case False from assms
- have "(map_of (zip xs ys)(x \<mapsto> y)) x' = (map_of (zip xs zs)(x \<mapsto> z)) x'" by auto
- with False show ?thesis by simp
- qed
-qed
-
-lemma map_of_zip_inject:
- assumes "length ys = length xs"
- and "length zs = length xs"
- and dist: "distinct xs"
- and map_of: "map_of (zip xs ys) = map_of (zip xs zs)"
- shows "ys = zs"
- using assms(1) assms(2)[symmetric]
- using dist map_of
-proof (induct ys xs zs rule: list_induct3)
- case Nil show ?case by simp
-next
- case (Cons y ys x xs z zs)
- from \<open>map_of (zip (x#xs) (y#ys)) = map_of (zip (x#xs) (z#zs))\<close>
- have map_of: "map_of (zip xs ys)(x \<mapsto> y) = map_of (zip xs zs)(x \<mapsto> z)" by simp
- from Cons have "length ys = length xs" and "length zs = length xs"
- and "x \<notin> set xs" by simp_all
- then have "map_of (zip xs ys) = map_of (zip xs zs)" using map_of by (rule map_of_zip_upd)
- with Cons.hyps \<open>distinct (x # xs)\<close> have "ys = zs" by simp
- moreover from map_of have "y = z" by (rule map_upd_eqD1)
- ultimately show ?case by simp
-qed
-
-lemma map_of_zip_nth:
- assumes "length xs = length ys"
- assumes "distinct xs"
- assumes "i < length ys"
- shows "map_of (zip xs ys) (xs ! i) = Some (ys ! i)"
-using assms proof (induct arbitrary: i rule: list_induct2)
- case Nil
- then show ?case by simp
-next
- case (Cons x xs y ys)
- then show ?case
- using less_Suc_eq_0_disj by auto
-qed
-
-lemma map_of_zip_map:
- "map_of (zip xs (map f xs)) = (\<lambda>x. if x \<in> set xs then Some (f x) else None)"
- by (induct xs) (simp_all add: fun_eq_iff)
-
lemma finite_range_map_of: "finite (range (map_of xys))"
proof (induct xys)
case (Cons a xys)
@@ -242,25 +139,6 @@
using finite_range_updI by fastforce
qed auto
-lemma map_of_SomeD: "map_of xs k = Some y \<Longrightarrow> (k, y) \<in> set xs"
- by (induct xs) (auto split: if_splits)
-
-lemma map_of_mapk_SomeI:
- "inj f \<Longrightarrow> map_of t k = Some x \<Longrightarrow>
- map_of (map (case_prod (\<lambda>k. Pair (f k))) t) (f k) = Some x"
-by (induct t) (auto simp: inj_eq)
-
-lemma weak_map_of_SomeI: "(k, x) \<in> set l \<Longrightarrow> \<exists>x. map_of l k = Some x"
-by (induct l) auto
-
-lemma map_of_filter_in:
- "map_of xs k = Some z \<Longrightarrow> P k z \<Longrightarrow> map_of (filter (case_prod P) xs) k = Some z"
-by (induct xs) auto
-
-lemma map_of_map:
- "map_of (map (\<lambda>(k, v). (k, f v)) xs) = map_option f \<circ> map_of xs"
- by (induct xs) (auto simp: fun_eq_iff)
-
lemma dom_map_option:
"dom (\<lambda>k. map_option (f k) (m k)) = dom m"
by (simp add: dom_def)