author | wenzelm |
Sat, 07 Aug 2010 14:45:26 +0200 | |
changeset 38222 | dac5fa0ac971 |
parent 37492 | ab36b1a50ca8 |
child 39198 | f967a16dfcdd |
permissions | -rw-r--r-- |
(* Title: HOL/Library/Quotient_List.thy Author: Cezary Kaliszyk and Christian Urban *) header {* Quotient infrastructure for the list type *} theory Quotient_List imports Main Quotient_Syntax begin declare [[map list = (map, list_all2)]] lemma split_list_all: shows "(\<forall>x. P x) \<longleftrightarrow> P [] \<and> (\<forall>x xs. P (x#xs))" apply(auto) apply(case_tac x) apply(simp_all) done lemma map_id[id_simps]: shows "map id = id" apply(simp add: expand_fun_eq) apply(rule allI) apply(induct_tac x) apply(simp_all) done lemma list_all2_reflp: shows "equivp R \<Longrightarrow> list_all2 R xs xs" by (induct xs, simp_all add: equivp_reflp) lemma list_all2_symp: assumes a: "equivp R" and b: "list_all2 R xs ys" shows "list_all2 R ys xs" using list_all2_lengthD[OF b] b apply(induct xs ys rule: list_induct2) apply(simp_all) apply(rule equivp_symp[OF a]) apply(simp) done thm list_induct3 lemma list_all2_transp: assumes a: "equivp R" and b: "list_all2 R xs1 xs2" and c: "list_all2 R xs2 xs3" shows "list_all2 R xs1 xs3" using list_all2_lengthD[OF b] list_all2_lengthD[OF c] b c apply(induct rule: list_induct3) apply(simp_all) apply(auto intro: equivp_transp[OF a]) done lemma list_equivp[quot_equiv]: assumes a: "equivp R" shows "equivp (list_all2 R)" apply (intro equivpI) unfolding reflp_def symp_def transp_def apply(simp add: list_all2_reflp[OF a]) apply(blast intro: list_all2_symp[OF a]) apply(blast intro: list_all2_transp[OF a]) done lemma list_all2_rel: assumes q: "Quotient R Abs Rep" shows "list_all2 R r s = (list_all2 R r r \<and> list_all2 R s s \<and> (map Abs r = map Abs s))" apply(induct r s rule: list_induct2') apply(simp_all) using Quotient_rel[OF q] apply(metis) done lemma list_quotient[quot_thm]: assumes q: "Quotient R Abs Rep" shows "Quotient (list_all2 R) (map Abs) (map Rep)" unfolding Quotient_def apply(subst split_list_all) apply(simp add: Quotient_abs_rep[OF q] abs_o_rep[OF q] map_id) apply(intro conjI allI) apply(induct_tac a) apply(simp_all add: Quotient_rep_reflp[OF q]) apply(rule list_all2_rel[OF q]) done lemma cons_prs_aux: assumes q: "Quotient R Abs Rep" shows "(map Abs) ((Rep h) # (map Rep t)) = h # t" by (induct t) (simp_all add: Quotient_abs_rep[OF q]) lemma cons_prs[quot_preserve]: assumes q: "Quotient R Abs Rep" shows "(Rep ---> (map Rep) ---> (map Abs)) (op #) = (op #)" by (simp only: expand_fun_eq fun_map_def cons_prs_aux[OF q]) (simp) lemma cons_rsp[quot_respect]: assumes q: "Quotient R Abs Rep" shows "(R ===> list_all2 R ===> list_all2 R) (op #) (op #)" by (auto) lemma nil_prs[quot_preserve]: assumes q: "Quotient R Abs Rep" shows "map Abs [] = []" by simp lemma nil_rsp[quot_respect]: assumes q: "Quotient R Abs Rep" shows "list_all2 R [] []" by simp lemma map_prs_aux: assumes a: "Quotient R1 abs1 rep1" and b: "Quotient R2 abs2 rep2" shows "(map abs2) (map ((abs1 ---> rep2) f) (map rep1 l)) = map f l" by (induct l) (simp_all add: Quotient_abs_rep[OF a] Quotient_abs_rep[OF b]) lemma map_prs[quot_preserve]: assumes a: "Quotient R1 abs1 rep1" and b: "Quotient R2 abs2 rep2" shows "((abs1 ---> rep2) ---> (map rep1) ---> (map abs2)) map = map" and "((abs1 ---> id) ---> map rep1 ---> id) map = map" by (simp_all only: expand_fun_eq fun_map_def map_prs_aux[OF a b]) (simp_all add: Quotient_abs_rep[OF a]) lemma map_rsp[quot_respect]: assumes q1: "Quotient R1 Abs1 Rep1" and q2: "Quotient R2 Abs2 Rep2" shows "((R1 ===> R2) ===> (list_all2 R1) ===> list_all2 R2) map map" and "((R1 ===> op =) ===> (list_all2 R1) ===> op =) map map" apply simp_all apply(rule_tac [!] allI)+ apply(rule_tac [!] impI) apply(rule_tac [!] allI)+ apply (induct_tac [!] xa ya rule: list_induct2') apply simp_all done lemma foldr_prs_aux: assumes a: "Quotient R1 abs1 rep1" and b: "Quotient R2 abs2 rep2" shows "abs2 (foldr ((abs1 ---> abs2 ---> rep2) f) (map rep1 l) (rep2 e)) = foldr f l e" by (induct l) (simp_all add: Quotient_abs_rep[OF a] Quotient_abs_rep[OF b]) lemma foldr_prs[quot_preserve]: assumes a: "Quotient R1 abs1 rep1" and b: "Quotient R2 abs2 rep2" shows "((abs1 ---> abs2 ---> rep2) ---> (map rep1) ---> rep2 ---> abs2) foldr = foldr" by (simp only: expand_fun_eq fun_map_def foldr_prs_aux[OF a b]) (simp) lemma foldl_prs_aux: assumes a: "Quotient R1 abs1 rep1" and b: "Quotient R2 abs2 rep2" shows "abs1 (foldl ((abs1 ---> abs2 ---> rep1) f) (rep1 e) (map rep2 l)) = foldl f e l" by (induct l arbitrary:e) (simp_all add: Quotient_abs_rep[OF a] Quotient_abs_rep[OF b]) lemma foldl_prs[quot_preserve]: assumes a: "Quotient R1 abs1 rep1" and b: "Quotient R2 abs2 rep2" shows "((abs1 ---> abs2 ---> rep1) ---> rep1 ---> (map rep2) ---> abs1) foldl = foldl" by (simp only: expand_fun_eq fun_map_def foldl_prs_aux[OF a b]) (simp) lemma list_all2_empty: shows "list_all2 R [] b \<Longrightarrow> length b = 0" by (induct b) (simp_all) (* induct_tac doesn't accept 'arbitrary', so we manually 'spec' *) lemma foldl_rsp[quot_respect]: assumes q1: "Quotient R1 Abs1 Rep1" and q2: "Quotient R2 Abs2 Rep2" shows "((R1 ===> R2 ===> R1) ===> R1 ===> list_all2 R2 ===> R1) foldl foldl" apply(auto) apply (subgoal_tac "R1 xa ya \<longrightarrow> list_all2 R2 xb yb \<longrightarrow> R1 (foldl x xa xb) (foldl y ya yb)") apply simp apply (rule_tac x="xa" in spec) apply (rule_tac x="ya" in spec) apply (rule_tac xs="xb" and ys="yb" in list_induct2) apply (rule list_all2_lengthD) apply (simp_all) done lemma foldr_rsp[quot_respect]: assumes q1: "Quotient R1 Abs1 Rep1" and q2: "Quotient R2 Abs2 Rep2" shows "((R1 ===> R2 ===> R2) ===> list_all2 R1 ===> R2 ===> R2) foldr foldr" apply auto apply(subgoal_tac "R2 xb yb \<longrightarrow> list_all2 R1 xa ya \<longrightarrow> R2 (foldr x xa xb) (foldr y ya yb)") apply simp apply (rule_tac xs="xa" and ys="ya" in list_induct2) apply (rule list_all2_lengthD) apply (simp_all) done lemma list_all2_rsp: assumes r: "\<forall>x y. R x y \<longrightarrow> (\<forall>a b. R a b \<longrightarrow> S x a = T y b)" and l1: "list_all2 R x y" and l2: "list_all2 R a b" shows "list_all2 S x a = list_all2 T y b" proof - have a: "length y = length x" by (rule list_all2_lengthD[OF l1, symmetric]) have c: "length a = length b" by (rule list_all2_lengthD[OF l2]) show ?thesis proof (cases "length x = length a") case True have b: "length x = length a" by fact show ?thesis using a b c r l1 l2 proof (induct rule: list_induct4) case Nil show ?case using assms by simp next case (Cons h t) then show ?case by auto qed next case False have d: "length x \<noteq> length a" by fact then have e: "\<not>list_all2 S x a" using list_all2_lengthD by auto have "length y \<noteq> length b" using d a c by simp then have "\<not>list_all2 T y b" using list_all2_lengthD by auto then show ?thesis using e by simp qed qed lemma[quot_respect]: "((R ===> R ===> op =) ===> list_all2 R ===> list_all2 R ===> op =) list_all2 list_all2" by (simp add: list_all2_rsp) lemma[quot_preserve]: assumes a: "Quotient R abs1 rep1" shows "((abs1 ---> abs1 ---> id) ---> map rep1 ---> map rep1 ---> id) list_all2 = list_all2" apply (simp add: expand_fun_eq) apply clarify apply (induct_tac xa xb rule: list_induct2') apply (simp_all add: Quotient_abs_rep[OF a]) done lemma[quot_preserve]: assumes a: "Quotient R abs1 rep1" shows "(list_all2 ((rep1 ---> rep1 ---> id) R) l m) = (l = m)" by (induct l m rule: list_induct2') (simp_all add: Quotient_rel_rep[OF a]) lemma list_all2_eq[id_simps]: shows "(list_all2 (op =)) = (op =)" unfolding expand_fun_eq apply(rule allI)+ apply(induct_tac x xa rule: list_induct2') apply(simp_all) done lemma list_all2_find_element: assumes a: "x \<in> set a" and b: "list_all2 R a b" shows "\<exists>y. (y \<in> set b \<and> R x y)" proof - have "length a = length b" using b by (rule list_all2_lengthD) then show ?thesis using a b by (induct a b rule: list_induct2) auto qed lemma list_all2_refl: assumes a: "\<And>x y. R x y = (R x = R y)" shows "list_all2 R x x" by (induct x) (auto simp add: a) end