# HG changeset patch # User wenzelm # Date 1467829191 -7200 # Node ID a95e7432d86c80d948780195df6b5798f846d902 # Parent a962f349c8c9fba030d30bd13ca6ea24b2ad494d misc tuning and modernization; diff -r a962f349c8c9 -r a95e7432d86c src/HOL/Finite_Set.thy --- a/src/HOL/Finite_Set.thy Wed Jul 06 14:09:13 2016 +0200 +++ b/src/HOL/Finite_Set.thy Wed Jul 06 20:19:51 2016 +0200 @@ -16,9 +16,9 @@ begin inductive finite :: "'a set \ bool" - where - emptyI [simp, intro!]: "finite {}" - | insertI [simp, intro!]: "finite A \ finite (insert a A)" +where + emptyI [simp, intro!]: "finite {}" +| insertI [simp, intro!]: "finite A \ finite (insert a A)" end @@ -32,14 +32,16 @@ assumes "P {}" and insert: "\x F. finite F \ x \ F \ P F \ P (insert x F)" shows "P F" -using \finite F\ + using \finite F\ proof induct show "P {}" by fact - fix x F assume F: "finite F" and P: "P F" +next + fix x F + assume F: "finite F" and P: "P F" show "P (insert x F)" proof cases assume "x \ F" - hence "insert x F = F" by (rule insert_absorb) + then have "insert x F = F" by (rule insert_absorb) with P show ?thesis by (simp only:) next assume "x \ F" @@ -49,13 +51,15 @@ lemma infinite_finite_induct [case_names infinite empty insert]: assumes infinite: "\A. \ finite A \ P A" - assumes empty: "P {}" - assumes insert: "\x F. finite F \ x \ F \ P F \ P (insert x F)" + and empty: "P {}" + and insert: "\x F. finite F \ x \ F \ P F \ P (insert x F)" shows "P A" proof (cases "finite A") - case False with infinite show ?thesis . + case False + with infinite show ?thesis . next - case True then show ?thesis by (induct A) (fact empty insert)+ + case True + then show ?thesis by (induct A) (fact empty insert)+ qed @@ -71,16 +75,18 @@ text \A finite choice principle. Does not need the SOME choice operator.\ -lemma finite_set_choice: - "finite A \ \x\A. \y. P x y \ \f. \x\A. P x (f x)" +lemma finite_set_choice: "finite A \ \x\A. \y. P x y \ \f. \x\A. P x (f x)" proof (induct rule: finite_induct) - case empty then show ?case by simp + case empty + then show ?case by simp next case (insert a A) - then obtain f b where f: "ALL x:A. P x (f x)" and ab: "P a b" by auto - show ?case (is "EX f. ?P f") + then obtain f b where f: "\x\A. P x (f x)" and ab: "P a b" + by auto + show ?case (is "\f. ?P f") proof - show "?P(%x. if x = a then b else f x)" using f ab by auto + show "?P (\x. if x = a then b else f x)" + using f ab by auto qed qed @@ -88,100 +94,101 @@ subsubsection \Finite sets are the images of initial segments of natural numbers\ lemma finite_imp_nat_seg_image_inj_on: - assumes "finite A" + assumes "finite A" shows "\(n::nat) f. A = f ` {i. i < n} \ inj_on f {i. i < n}" -using assms + using assms proof induct case empty show ?case proof - show "\f. {} = f ` {i::nat. i < 0} \ inj_on f {i. i < 0}" by simp + show "\f. {} = f ` {i::nat. i < 0} \ inj_on f {i. i < 0}" + by simp qed next case (insert a A) have notinA: "a \ A" by fact - from insert.hyps obtain n f - where "A = f ` {i::nat. i < n}" "inj_on f {i. i < n}" by blast - hence "insert a A = f(n:=a) ` {i. i < Suc n}" - "inj_on (f(n:=a)) {i. i < Suc n}" using notinA - by (auto simp add: image_def Ball_def inj_on_def less_Suc_eq) - thus ?case by blast + from insert.hyps obtain n f where "A = f ` {i::nat. i < n}" "inj_on f {i. i < n}" + by blast + then have "insert a A = f(n:=a) ` {i. i < Suc n}" and "inj_on (f(n:=a)) {i. i < Suc n}" + using notinA by (auto simp add: image_def Ball_def inj_on_def less_Suc_eq) + then show ?case by blast qed -lemma nat_seg_image_imp_finite: - "A = f ` {i::nat. i < n} \ finite A" +lemma nat_seg_image_imp_finite: "A = f ` {i::nat. i < n} \ finite A" proof (induct n arbitrary: A) - case 0 thus ?case by simp + case 0 + then show ?case by simp next case (Suc n) let ?B = "f ` {i. i < n}" - have finB: "finite ?B" by(rule Suc.hyps[OF refl]) + have finB: "finite ?B" by (rule Suc.hyps[OF refl]) show ?case - proof cases - assume "\kk(\ k (\(n::nat) f. A = f ` {i::nat. i < n})" +lemma finite_conv_nat_seg_image: "finite A \ (\(n::nat) f. A = f ` {i::nat. i < n})" by (blast intro: nat_seg_image_imp_finite dest: finite_imp_nat_seg_image_inj_on) lemma finite_imp_inj_to_nat_seg: assumes "finite A" shows "\f n::nat. f ` A = {i. i < n} \ inj_on f A" proof - - from finite_imp_nat_seg_image_inj_on[OF \finite A\] + from finite_imp_nat_seg_image_inj_on [OF \finite A\] obtain f and n::nat where bij: "bij_betw f {i. i ?f ` A = {i. i k}" +lemma finite_Collect_le_nat [iff]: "finite {n::nat. n \ k}" by (simp add: le_eq_less_or_eq Collect_disj_eq) subsubsection \Finiteness and common set operations\ -lemma rev_finite_subset: - "finite B \ A \ B \ finite A" +lemma rev_finite_subset: "finite B \ A \ B \ finite A" proof (induct arbitrary: A rule: finite_induct) case empty then show ?case by simp next case (insert x F A) - have A: "A \ insert x F" and r: "A - {x} \ F \ finite (A - {x})" by fact+ + have A: "A \ insert x F" and r: "A - {x} \ F \ finite (A - {x})" + by fact+ show "finite A" proof cases assume x: "x \ A" with A have "A - {x} \ F" by (simp add: subset_insert_iff) with r have "finite (A - {x})" . - hence "finite (insert x (A - {x}))" .. - also have "insert x (A - {x}) = A" using x by (rule insert_Diff) + then have "finite (insert x (A - {x}))" .. + also have "insert x (A - {x}) = A" + using x by (rule insert_Diff) finally show ?thesis . next show ?thesis when "A \ F" using that by fact assume "x \ A" - with A show "A \ F" by (simp add: subset_insert_iff) + with A show "A \ F" + by (simp add: subset_insert_iff) qed qed -lemma finite_subset: - "A \ B \ finite B \ finite A" +lemma finite_subset: "A \ B \ finite B \ finite A" by (rule rev_finite_subset) lemma finite_UnI: @@ -189,8 +196,7 @@ shows "finite (F \ G)" using assms by induct simp_all -lemma finite_Un [iff]: - "finite (F \ G) \ finite F \ finite G" +lemma finite_Un [iff]: "finite (F \ G) \ finite F \ finite G" by (blast intro: finite_UnI finite_subset [of _ "F \ G"]) lemma finite_insert [simp]: "finite (insert a A) \ finite A" @@ -200,8 +206,7 @@ then show ?thesis by simp qed -lemma finite_Int [simp, intro]: - "finite F \ finite G \ finite (F \ G)" +lemma finite_Int [simp, intro]: "finite F \ finite G \ finite (F \ G)" by (blast intro: finite_subset) lemma finite_Collect_conjI [simp, intro]: @@ -212,112 +217,110 @@ "finite {x. P x \ Q x} \ finite {x. P x} \ finite {x. Q x}" by (simp add: Collect_disj_eq) -lemma finite_Diff [simp, intro]: - "finite A \ finite (A - B)" +lemma finite_Diff [simp, intro]: "finite A \ finite (A - B)" by (rule finite_subset, rule Diff_subset) lemma finite_Diff2 [simp]: assumes "finite B" shows "finite (A - B) \ finite A" proof - - have "finite A \ finite((A - B) \ (A \ B))" by (simp add: Un_Diff_Int) - also have "\ \ finite (A - B)" using \finite B\ by simp + have "finite A \ finite ((A - B) \ (A \ B))" + by (simp add: Un_Diff_Int) + also have "\ \ finite (A - B)" + using \finite B\ by simp finally show ?thesis .. qed -lemma finite_Diff_insert [iff]: - "finite (A - insert a B) \ finite (A - B)" +lemma finite_Diff_insert [iff]: "finite (A - insert a B) \ finite (A - B)" proof - have "finite (A - B) \ finite (A - B - {a})" by simp moreover have "A - insert a B = A - B - {a}" by auto ultimately show ?thesis by simp qed -lemma finite_compl[simp]: +lemma finite_compl [simp]: "finite (A :: 'a set) \ finite (- A) \ finite (UNIV :: 'a set)" by (simp add: Compl_eq_Diff_UNIV) -lemma finite_Collect_not[simp]: +lemma finite_Collect_not [simp]: "finite {x :: 'a. P x} \ finite {x. \ P x} \ finite (UNIV :: 'a set)" by (simp add: Collect_neg_eq) lemma finite_Union [simp, intro]: - "finite A \ (\M. M \ A \ finite M) \ finite(\A)" + "finite A \ (\M. M \ A \ finite M) \ finite (\A)" by (induct rule: finite_induct) simp_all lemma finite_UN_I [intro]: "finite A \ (\a. a \ A \ finite (B a)) \ finite (\a\A. B a)" by (induct rule: finite_induct) simp_all -lemma finite_UN [simp]: - "finite A \ finite (UNION A B) \ (\x\A. finite (B x))" +lemma finite_UN [simp]: "finite A \ finite (UNION A B) \ (\x\A. finite (B x))" by (blast intro: finite_subset) -lemma finite_Inter [intro]: - "\A\M. finite A \ finite (\M)" +lemma finite_Inter [intro]: "\A\M. finite A \ finite (\M)" by (blast intro: Inter_lower finite_subset) -lemma finite_INT [intro]: - "\x\I. finite (A x) \ finite (\x\I. A x)" +lemma finite_INT [intro]: "\x\I. finite (A x) \ finite (\x\I. A x)" by (blast intro: INT_lower finite_subset) -lemma finite_imageI [simp, intro]: - "finite F \ finite (h ` F)" +lemma finite_imageI [simp, intro]: "finite F \ finite (h ` F)" by (induct rule: finite_induct) simp_all -lemma finite_image_set [simp]: - "finite {x. P x} \ finite { f x | x. P x }" +lemma finite_image_set [simp]: "finite {x. P x} \ finite {f x |x. P x}" by (simp add: image_Collect [symmetric]) lemma finite_image_set2: - "finite {x. P x} \ finite {y. Q y} \ finite {f x y | x y. P x \ Q y}" + "finite {x. P x} \ finite {y. Q y} \ finite {f x y |x y. P x \ Q y}" by (rule finite_subset [where B = "\x \ {x. P x}. \y \ {y. Q y}. {f x y}"]) auto lemma finite_imageD: assumes "finite (f ` A)" and "inj_on f A" shows "finite A" -using assms + using assms proof (induct "f ` A" arbitrary: A) - case empty then show ?case by simp + case empty + then show ?case by simp next case (insert x B) - then have B_A: "insert x B = f ` A" by simp - then obtain y where "x = f y" and "y \ A" by blast - from B_A \x \ B\ have "B = f ` A - {x}" by blast - with B_A \x \ B\ \x = f y\ \inj_on f A\ \y \ A\ have "B = f ` (A - {y})" + then have B_A: "insert x B = f ` A" + by simp + then obtain y where "x = f y" and "y \ A" + by blast + from B_A \x \ B\ have "B = f ` A - {x}" + by blast + with B_A \x \ B\ \x = f y\ \inj_on f A\ \y \ A\ have "B = f ` (A - {y})" by (simp add: inj_on_image_set_diff Set.Diff_subset) - moreover from \inj_on f A\ have "inj_on f (A - {y})" by (rule inj_on_diff) - ultimately have "finite (A - {y})" by (rule insert.hyps) - then show "finite A" by simp + moreover from \inj_on f A\ have "inj_on f (A - {y})" + by (rule inj_on_diff) + ultimately have "finite (A - {y})" + by (rule insert.hyps) + then show "finite A" + by simp qed -lemma finite_image_iff: - assumes "inj_on f A" - shows "finite (f ` A) \ finite A" -using assms finite_imageD by blast +lemma finite_image_iff: "inj_on f A \ finite (f ` A) \ finite A" + using finite_imageD by blast -lemma finite_surj: - "finite A \ B \ f ` A \ finite B" +lemma finite_surj: "finite A \ B \ f ` A \ finite B" by (erule finite_subset) (rule finite_imageI) -lemma finite_range_imageI: - "finite (range g) \ finite (range (\x. f (g x)))" +lemma finite_range_imageI: "finite (range g) \ finite (range (\x. f (g x)))" by (drule finite_imageI) (simp add: range_composition) lemma finite_subset_image: assumes "finite B" shows "B \ f ` A \ \C\A. finite C \ B = f ` C" -using assms + using assms proof induct - case empty then show ?case by simp + case empty + then show ?case by simp next - case insert then show ?case - by (clarsimp simp del: image_insert simp add: image_insert [symmetric]) - blast + case insert + then show ?case + by (clarsimp simp del: image_insert simp add: image_insert [symmetric]) blast qed -lemma finite_vimage_IntI: - "finite F \ inj_on h A \ finite (h -` F \ A)" +lemma finite_vimage_IntI: "finite F \ inj_on h A \ finite (h -` F \ A)" apply (induct rule: finite_induct) apply simp_all apply (subst vimage_insert) @@ -334,15 +337,14 @@ by (simp only: * assms finite_UN_I) qed -lemma finite_vimageI: - "finite F \ inj h \ finite (h -` F)" +lemma finite_vimageI: "finite F \ inj h \ finite (h -` F)" using finite_vimage_IntI[of F h UNIV] by auto -lemma finite_vimageD': "\ finite (f -` A); A \ range f \ \ finite A" -by(auto simp add: subset_image_iff intro: finite_subset[rotated]) +lemma finite_vimageD': "finite (f -` A) \ A \ range f \ finite A" + by (auto simp add: subset_image_iff intro: finite_subset[rotated]) -lemma finite_vimageD: "\ finite (h -` F); surj h \ \ finite F" -by(auto dest: finite_vimageD') +lemma finite_vimageD: "finite (h -` F) \ surj h \ finite F" + by (auto dest: finite_vimageD') lemma finite_vimage_iff: "bij h \ finite (h -` F) \ finite F" unfolding bij_def by (auto elim: finite_vimageD finite_vimageI) @@ -359,30 +361,36 @@ assumes "finite {y. P y}" shows "finite {x. \y. P y \ Q x y} \ (\y. P y \ finite {x. Q x y})" proof - - have "{x. EX y. P y & Q x y} = (\y\{y. P y}. {x. Q x y})" by auto - with assms show ?thesis by simp + have "{x. \y. P y \ Q x y} = (\y\{y. P y}. {x. Q x y})" + by auto + with assms show ?thesis + by simp qed -lemma finite_Plus: - "finite A \ finite B \ finite (A <+> B)" +lemma finite_Plus: "finite A \ finite B \ finite (A <+> B)" by (simp add: Plus_def) -lemma finite_PlusD: +lemma finite_PlusD: fixes A :: "'a set" and B :: "'b set" assumes fin: "finite (A <+> B)" shows "finite A" "finite B" proof - - have "Inl ` A \ A <+> B" by auto - then have "finite (Inl ` A :: ('a + 'b) set)" using fin by (rule finite_subset) - then show "finite A" by (rule finite_imageD) (auto intro: inj_onI) + have "Inl ` A \ A <+> B" + by auto + then have "finite (Inl ` A :: ('a + 'b) set)" + using fin by (rule finite_subset) + then show "finite A" + by (rule finite_imageD) (auto intro: inj_onI) next - have "Inr ` B \ A <+> B" by auto - then have "finite (Inr ` B :: ('a + 'b) set)" using fin by (rule finite_subset) - then show "finite B" by (rule finite_imageD) (auto intro: inj_onI) + have "Inr ` B \ A <+> B" + by auto + then have "finite (Inr ` B :: ('a + 'b) set)" + using fin by (rule finite_subset) + then show "finite B" + by (rule finite_imageD) (auto intro: inj_onI) qed -lemma finite_Plus_iff [simp]: - "finite (A <+> B) \ finite A \ finite B" +lemma finite_Plus_iff [simp]: "finite (A <+> B) \ finite A \ finite B" by (auto intro: finite_PlusD finite_Plus) lemma finite_Plus_UNIV_iff [simp]: @@ -390,21 +398,22 @@ by (subst UNIV_Plus_UNIV [symmetric]) (rule finite_Plus_iff) lemma finite_SigmaI [simp, intro]: - "finite A \ (\a. a\A \ finite (B a)) ==> finite (SIGMA a:A. B a)" - by (unfold Sigma_def) blast + "finite A \ (\a. a\A \ finite (B a)) \ finite (SIGMA a:A. B a)" + unfolding Sigma_def by blast lemma finite_SigmaI2: assumes "finite {x\A. B x \ {}}" and "\a. a \ A \ finite (B a)" shows "finite (Sigma A B)" proof - - from assms have "finite (Sigma {x\A. B x \ {}} B)" by auto - also have "Sigma {x:A. B x \ {}} B = Sigma A B" by auto + from assms have "finite (Sigma {x\A. B x \ {}} B)" + by auto + also have "Sigma {x:A. B x \ {}} B = Sigma A B" + by auto finally show ?thesis . qed -lemma finite_cartesian_product: - "finite A \ finite B \ finite (A \ B)" +lemma finite_cartesian_product: "finite A \ finite B \ finite (A \ B)" by (rule finite_SigmaI) lemma finite_Prod_UNIV: @@ -417,10 +426,12 @@ proof - from assms obtain n f where "A \ B = f ` {i::nat. i < n}" by (auto simp add: finite_conv_nat_seg_image) - then have "fst ` (A \ B) = fst ` f ` {i::nat. i < n}" by simp + then have "fst ` (A \ B) = fst ` f ` {i::nat. i < n}" + by simp with \B \ {}\ have "A = (fst \ f) ` {i::nat. i < n}" by (simp add: image_comp) - then have "\n f. A = f ` {i::nat. i < n}" by blast + then have "\n f. A = f ` {i::nat. i < n}" + by blast then show ?thesis by (auto simp add: finite_conv_nat_seg_image) qed @@ -431,10 +442,12 @@ proof - from assms obtain n f where "A \ B = f ` {i::nat. i < n}" by (auto simp add: finite_conv_nat_seg_image) - then have "snd ` (A \ B) = snd ` f ` {i::nat. i < n}" by simp + then have "snd ` (A \ B) = snd ` f ` {i::nat. i < n}" + by simp with \A \ {}\ have "B = (snd \ f) ` {i::nat. i < n}" by (simp add: image_comp) - then have "\n f. B = f ` {i::nat. i < n}" by blast + then have "\n f. B = f ` {i::nat. i < n}" + by blast then show ?thesis by (auto simp add: finite_conv_nat_seg_image) qed @@ -443,48 +456,52 @@ "finite (A \ B) \ (A = {} \ B = {} \ (finite A \ finite B))" by (auto dest: finite_cartesian_productD1 finite_cartesian_productD2 finite_cartesian_product) -lemma finite_prod: +lemma finite_prod: "finite (UNIV :: ('a \ 'b) set) \ finite (UNIV :: 'a set) \ finite (UNIV :: 'b set)" using finite_cartesian_product_iff[of UNIV UNIV] by simp -lemma finite_Pow_iff [iff]: - "finite (Pow A) \ finite A" +lemma finite_Pow_iff [iff]: "finite (Pow A) \ finite A" proof assume "finite (Pow A)" - then have "finite ((%x. {x}) ` A)" by (blast intro: finite_subset) - then show "finite A" by (rule finite_imageD [unfolded inj_on_def]) simp + then have "finite ((\x. {x}) ` A)" + by (blast intro: finite_subset) + then show "finite A" + by (rule finite_imageD [unfolded inj_on_def]) simp next assume "finite A" then show "finite (Pow A)" by induct (simp_all add: Pow_insert) qed -corollary finite_Collect_subsets [simp, intro]: - "finite A \ finite {B. B \ A}" +corollary finite_Collect_subsets [simp, intro]: "finite A \ finite {B. B \ A}" by (simp add: Pow_def [symmetric]) lemma finite_set: "finite (UNIV :: 'a set set) \ finite (UNIV :: 'a set)" -by(simp only: finite_Pow_iff Pow_UNIV[symmetric]) + by (simp only: finite_Pow_iff Pow_UNIV[symmetric]) -lemma finite_UnionD: "finite(\A) \ finite A" +lemma finite_UnionD: "finite (\A) \ finite A" by (blast intro: finite_subset [OF subset_Pow_Union]) -lemma finite_set_of_finite_funs: assumes "finite A" "finite B" -shows "finite{f. \x. (x \ A \ f x \ B) \ (x \ A \ f x = d)}" (is "finite ?S") -proof- +lemma finite_set_of_finite_funs: + assumes "finite A" "finite B" + shows "finite {f. \x. (x \ A \ f x \ B) \ (x \ A \ f x = d)}" (is "finite ?S") +proof - let ?F = "\f. {(a,b). a \ A \ b = f a}" - have "?F ` ?S \ Pow(A \ B)" by auto - from finite_subset[OF this] assms have 1: "finite (?F ` ?S)" by simp + have "?F ` ?S \ Pow(A \ B)" + by auto + from finite_subset[OF this] assms have 1: "finite (?F ` ?S)" + by simp have 2: "inj_on ?F ?S" - by(fastforce simp add: inj_on_def set_eq_iff fun_eq_iff) - show ?thesis by(rule finite_imageD[OF 1 2]) + by (fastforce simp add: inj_on_def set_eq_iff fun_eq_iff) + show ?thesis + by (rule finite_imageD [OF 1 2]) qed lemma not_finite_existsD: assumes "\ finite {a. P a}" shows "\a. P a" proof (rule classical) - assume "\ (\a. P a)" + assume "\ ?thesis" with assms show ?thesis by auto qed @@ -496,11 +513,13 @@ assumes "\x. P {x}" and "\x F. finite F \ F \ {} \ x \ F \ P F \ P (insert x F)" shows "P F" -using assms + using assms proof induct - case empty then show ?case by simp + case empty + then show ?case by simp next - case (insert x F) then show ?case by cases auto + case (insert x F) + then show ?case by cases auto qed lemma finite_subset_induct [consumes 2, case_names empty insert]: @@ -508,13 +527,12 @@ assumes empty: "P {}" and insert: "\a F. finite F \ a \ A \ a \ F \ P F \ P (insert a F)" shows "P F" -using \finite F\ \F \ A\ + using \finite F\ \F \ A\ proof induct show "P {}" by fact next fix x F - assume "finite F" and "x \ F" and - P: "F \ A \ P F" and i: "insert x F \ A" + assume "finite F" and "x \ F" and P: "F \ A \ P F" and i: "insert x F \ A" show "P (insert x F)" proof (rule insert) from i show "x \ A" by blast @@ -531,11 +549,10 @@ and remove: "\a A. finite A \ a \ A \ P A \ P (A - {a})" shows "P {}" proof - - have "\B. B \ A \ P (A - B)" + have "P (A - B)" if "B \ A" for B :: "'a set" proof - - fix B :: "'a set" - assume "B \ A" - with \finite A\ have "finite B" by (rule rev_finite_subset) + from \finite A\ that have "finite B" + by (rule rev_finite_subset) from this \B \ A\ show "P (A - B)" proof induct case empty @@ -544,11 +561,15 @@ case (insert b B) have "P (A - B - {b})" proof (rule remove) - from \finite A\ show "finite (A - B)" by induct auto - from insert show "b \ A - B" by simp - from insert show "P (A - B)" by simp + from \finite A\ show "finite (A - B)" + by induct auto + from insert show "b \ A - B" + by simp + from insert show "P (A - B)" + by simp qed - also have "A - B - {b} = A - insert b B" by (rule Diff_insert [symmetric]) + also have "A - B - {b} = A - insert b B" + by (rule Diff_insert [symmetric]) finally show ?case . qed qed @@ -558,11 +579,13 @@ lemma finite_update_induct [consumes 1, case_names const update]: assumes finite: "finite {a. f a \ c}" - assumes const: "P (\a. c)" - assumes update: "\a b f. finite {a. f a \ c} \ f a = c \ b \ c \ P f \ P (f(a := b))" + and const: "P (\a. c)" + and update: "\a b f. finite {a. f a \ c} \ f a = c \ b \ c \ P f \ P (f(a := b))" shows "P f" -using finite proof (induct "{a. f a \ c}" arbitrary: f) - case empty with const show ?case by simp + using finite +proof (induct "{a. f a \ c}" arbitrary: f) + case empty + with const show ?case by simp next case (insert a A) then have "A = {a'. (f(a := c)) a' \ c}" and "f a \ c" @@ -573,7 +596,8 @@ by simp from insert \A = {a'. (f(a := c)) a' \ c}\ have "P (f(a := c))" by simp - with \finite {a'. (f(a := c)) a' \ c}\ \(f(a := c)) a = c\ \f a \ c\ have "P ((f(a := c))(a := f a))" + with \finite {a'. (f(a := c)) a' \ c}\ \(f(a := c)) a = c\ \f a \ c\ + have "P ((f(a := c))(a := f a))" by (rule update) then show ?case by simp qed @@ -581,8 +605,7 @@ subsection \Class \finite\\ -class finite = - assumes finite_UNIV: "finite (UNIV :: 'a set)" +class finite = assumes finite_UNIV: "finite (UNIV :: 'a set)" begin lemma finite [simp]: "finite (A :: 'a set)" @@ -596,20 +619,22 @@ instance prod :: (finite, finite) finite by standard (simp only: UNIV_Times_UNIV [symmetric] finite_cartesian_product finite) -lemma inj_graph: "inj (%f. {(x, y). y = f x})" - by (rule inj_onI, auto simp add: set_eq_iff fun_eq_iff) +lemma inj_graph: "inj (\f. {(x, y). y = f x})" + by (rule inj_onI) (auto simp add: set_eq_iff fun_eq_iff) instance "fun" :: (finite, finite) finite proof - show "finite (UNIV :: ('a => 'b) set)" + show "finite (UNIV :: ('a \ 'b) set)" proof (rule finite_imageD) - let ?graph = "%f::'a => 'b. {(x, y). y = f x}" - have "range ?graph \ Pow UNIV" by simp + let ?graph = "\f::'a \ 'b. {(x, y). y = f x}" + have "range ?graph \ Pow UNIV" + by simp moreover have "finite (Pow (UNIV :: ('a * 'b) set))" by (simp only: finite_Pow_iff finite) ultimately show "finite (range ?graph)" by (rule finite_subset) - show "inj ?graph" by (rule inj_graph) + show "inj ?graph" + by (rule inj_graph) qed qed @@ -629,8 +654,8 @@ subsection \A basic fold functional for finite sets\ text \The intended behaviour is -\fold f z {x\<^sub>1, ..., x\<^sub>n} = f x\<^sub>1 (\ (f x\<^sub>n z)\)\ -if \f\ is ``left-commutative'': + \fold f z {x\<^sub>1, \, x\<^sub>n} = f x\<^sub>1 (\ (f x\<^sub>n z)\)\ + if \f\ is ``left-commutative'': \ locale comp_fun_commute = @@ -641,34 +666,35 @@ lemma fun_left_comm: "f y (f x z) = f x (f y z)" using comp_fun_commute by (simp add: fun_eq_iff) -lemma commute_left_comp: - "f y \ (f x \ g) = f x \ (f y \ g)" +lemma commute_left_comp: "f y \ (f x \ g) = f x \ (f y \ g)" by (simp add: o_assoc comp_fun_commute) end inductive fold_graph :: "('a \ 'b \ 'b) \ 'b \ 'a set \ 'b \ bool" -for f :: "'a \ 'b \ 'b" and z :: 'b where - emptyI [intro]: "fold_graph f z {} z" | - insertI [intro]: "x \ A \ fold_graph f z A y - \ fold_graph f z (insert x A) (f x y)" + for f :: "'a \ 'b \ 'b" and z :: 'b +where + emptyI [intro]: "fold_graph f z {} z" +| insertI [intro]: "x \ A \ fold_graph f z A y \ fold_graph f z (insert x A) (f x y)" inductive_cases empty_fold_graphE [elim!]: "fold_graph f z {} x" -definition fold :: "('a \ 'b \ 'b) \ 'b \ 'a set \ 'b" where - "fold f z A = (if finite A then (THE y. fold_graph f z A y) else z)" +definition fold :: "('a \ 'b \ 'b) \ 'b \ 'a set \ 'b" + where "fold f z A = (if finite A then (THE y. fold_graph f z A y) else z)" -text\A tempting alternative for the definiens is -@{term "if finite A then THE y. fold_graph f z A y else e"}. -It allows the removal of finiteness assumptions from the theorems -\fold_comm\, \fold_reindex\ and \fold_distrib\. -The proofs become ugly. It is not worth the effort. (???)\ +text \ + A tempting alternative for the definiens is + @{term "if finite A then THE y. fold_graph f z A y else e"}. + It allows the removal of finiteness assumptions from the theorems + \fold_comm\, \fold_reindex\ and \fold_distrib\. + The proofs become ugly. It is not worth the effort. (???) +\ lemma finite_imp_fold_graph: "finite A \ \x. fold_graph f z A x" -by (induct rule: finite_induct) auto + by (induct rule: finite_induct) auto -subsubsection\From @{const fold_graph} to @{term fold}\ +subsubsection \From @{const fold_graph} to @{term fold}\ context comp_fun_commute begin @@ -681,11 +707,16 @@ lemma fold_graph_insertE_aux: "fold_graph f z A y \ a \ A \ \y'. y = f a y' \ fold_graph f z (A - {a}) y'" proof (induct set: fold_graph) - case (insertI x A y) show ?case + case emptyI + then show ?case by simp +next + case (insertI x A y) + show ?case proof (cases "x = a") - assume "x = a" with insertI show ?case by auto + case True + with insertI show ?thesis by auto next - assume "x \ a" + case False then obtain y' where y: "y = f a y'" and y': "fold_graph f z (A - {a}) y'" using insertI by auto have "f x y = f a (f x y')" @@ -693,86 +724,96 @@ moreover have "fold_graph f z (insert x A - {a}) (f x y')" using y' and \x \ a\ and \x \ A\ by (simp add: insert_Diff_if fold_graph.insertI) - ultimately show ?case by fast + ultimately show ?thesis + by fast qed -qed simp +qed lemma fold_graph_insertE: assumes "fold_graph f z (insert x A) v" and "x \ A" obtains y where "v = f x y" and "fold_graph f z A y" -using assms by (auto dest: fold_graph_insertE_aux [OF _ insertI1]) + using assms by (auto dest: fold_graph_insertE_aux [OF _ insertI1]) -lemma fold_graph_determ: - "fold_graph f z A x \ fold_graph f z A y \ y = x" +lemma fold_graph_determ: "fold_graph f z A x \ fold_graph f z A y \ y = x" proof (induct arbitrary: y set: fold_graph) + case emptyI + then show ?case by fast +next case (insertI x A y v) from \fold_graph f z (insert x A) v\ and \x \ A\ obtain y' where "v = f x y'" and "fold_graph f z A y'" by (rule fold_graph_insertE) - from \fold_graph f z A y'\ have "y' = y" by (rule insertI) - with \v = f x y'\ show "v = f x y" by simp -qed fast + from \fold_graph f z A y'\ have "y' = y" + by (rule insertI) + with \v = f x y'\ show "v = f x y" + by simp +qed -lemma fold_equality: - "fold_graph f z A y \ fold f z A = y" +lemma fold_equality: "fold_graph f z A y \ fold f z A = y" by (cases "finite A") (auto simp add: fold_def intro: fold_graph_determ dest: fold_graph_finite) lemma fold_graph_fold: assumes "finite A" shows "fold_graph f z A (fold f z A)" proof - - from assms have "\x. fold_graph f z A x" by (rule finite_imp_fold_graph) + from assms have "\x. fold_graph f z A x" + by (rule finite_imp_fold_graph) moreover note fold_graph_determ - ultimately have "\!x. fold_graph f z A x" by (rule ex_ex1I) - then have "fold_graph f z A (The (fold_graph f z A))" by (rule theI') - with assms show ?thesis by (simp add: fold_def) + ultimately have "\!x. fold_graph f z A x" + by (rule ex_ex1I) + then have "fold_graph f z A (The (fold_graph f z A))" + by (rule theI') + with assms show ?thesis + by (simp add: fold_def) qed text \The base case for \fold\:\ -lemma (in -) fold_infinite [simp]: - assumes "\ finite A" - shows "fold f z A = z" - using assms by (auto simp add: fold_def) +lemma (in -) fold_infinite [simp]: "\ finite A \ fold f z A = z" + by (auto simp: fold_def) -lemma (in -) fold_empty [simp]: - "fold f z {} = z" - by (auto simp add: fold_def) +lemma (in -) fold_empty [simp]: "fold f z {} = z" + by (auto simp: fold_def) -text\The various recursion equations for @{const fold}:\ +text \The various recursion equations for @{const fold}:\ lemma fold_insert [simp]: assumes "finite A" and "x \ A" shows "fold f z (insert x A) = f x (fold f z A)" proof (rule fold_equality) fix z - from \finite A\ have "fold_graph f z A (fold f z A)" by (rule fold_graph_fold) - with \x \ A\ have "fold_graph f z (insert x A) (f x (fold f z A))" by (rule fold_graph.insertI) - then show "fold_graph f z (insert x A) (f x (fold f z A))" by simp + from \finite A\ have "fold_graph f z A (fold f z A)" + by (rule fold_graph_fold) + with \x \ A\ have "fold_graph f z (insert x A) (f x (fold f z A))" + by (rule fold_graph.insertI) + then show "fold_graph f z (insert x A) (f x (fold f z A))" + by simp qed declare (in -) empty_fold_graphE [rule del] fold_graph.intros [rule del] \ \No more proofs involve these.\ -lemma fold_fun_left_comm: - "finite A \ f x (fold f z A) = fold f (f x z) A" +lemma fold_fun_left_comm: "finite A \ f x (fold f z A) = fold f (f x z) A" proof (induct rule: finite_induct) - case empty then show ?case by simp + case empty + then show ?case by simp next - case (insert y A) then show ?case + case insert + then show ?case by (simp add: fun_left_comm [of x]) qed -lemma fold_insert2: - "finite A \ x \ A \ fold f z (insert x A) = fold f (f x z) A" +lemma fold_insert2: "finite A \ x \ A \ fold f z (insert x A) = fold f (f x z) A" by (simp add: fold_fun_left_comm) lemma fold_rec: assumes "finite A" and "x \ A" shows "fold f z A = f x (fold f z (A - {x}))" proof - - have A: "A = insert x (A - {x})" using \x \ A\ by blast - then have "fold f z A = fold f z (insert x (A - {x}))" by simp + have A: "A = insert x (A - {x})" + using \x \ A\ by blast + then have "fold f z A = fold f z (insert x (A - {x}))" + by simp also have "\ = f x (fold f z (A - {x}))" by (rule fold_insert) (simp add: \finite A\)+ finally show ?thesis . @@ -782,27 +823,32 @@ assumes "finite A" shows "fold f z (insert x A) = f x (fold f z (A - {x}))" proof - - from \finite A\ have "finite (insert x A)" by auto - moreover have "x \ insert x A" by auto + from \finite A\ have "finite (insert x A)" + by auto + moreover have "x \ insert x A" + by auto ultimately have "fold f z (insert x A) = f x (fold f z (insert x A - {x}))" by (rule fold_rec) - then show ?thesis by simp + then show ?thesis + by simp qed lemma fold_set_union_disj: assumes "finite A" "finite B" "A \ B = {}" shows "Finite_Set.fold f z (A \ B) = Finite_Set.fold f (Finite_Set.fold f z A) B" -using assms(2,1,3) by induction simp_all + using assms(2,1,3) by induct simp_all end -text\Other properties of @{const fold}:\ +text \Other properties of @{const fold}:\ lemma fold_image: assumes "inj_on g A" shows "fold f z (g ` A) = fold (f \ g) z A" proof (cases "finite A") - case False with assms show ?thesis by (auto dest: finite_imageD simp add: fold_def) + case False + with assms show ?thesis + by (auto dest: finite_imageD simp add: fold_def) next case True have "fold_graph f z (g ` A) = fold_graph (f \ g) z A" @@ -810,48 +856,63 @@ fix w show "fold_graph f z (g ` A) w \ fold_graph (f \ g) z A w" (is "?P \ ?Q") proof - assume ?P then show ?Q using assms + assume ?P + then show ?Q + using assms proof (induct "g ` A" w arbitrary: A) - case emptyI then show ?case by (auto intro: fold_graph.emptyI) + case emptyI + then show ?case by (auto intro: fold_graph.emptyI) next case (insertI x A r B) - from \inj_on g B\ \x \ A\ \insert x A = image g B\ obtain x' A' where - "x' \ A'" and [simp]: "B = insert x' A'" "x = g x'" "A = g ` A'" + from \inj_on g B\ \x \ A\ \insert x A = image g B\ obtain x' A' + where "x' \ A'" and [simp]: "B = insert x' A'" "x = g x'" "A = g ` A'" by (rule inj_img_insertE) - from insertI.prems have "fold_graph (f o g) z A' r" + from insertI.prems have "fold_graph (f \ g) z A' r" by (auto intro: insertI.hyps) with \x' \ A'\ have "fold_graph (f \ g) z (insert x' A') ((f \ g) x' r)" by (rule fold_graph.insertI) - then show ?case by simp + then show ?case + by simp qed next - assume ?Q then show ?P using assms + assume ?Q + then show ?P + using assms proof induct - case emptyI thus ?case by (auto intro: fold_graph.emptyI) + case emptyI + then show ?case + by (auto intro: fold_graph.emptyI) next case (insertI x A r) - from \x \ A\ insertI.prems have "g x \ g ` A" by auto - moreover from insertI have "fold_graph f z (g ` A) r" by simp + from \x \ A\ insertI.prems have "g x \ g ` A" + by auto + moreover from insertI have "fold_graph f z (g ` A) r" + by simp ultimately have "fold_graph f z (insert (g x) (g ` A)) (f (g x) r)" by (rule fold_graph.insertI) - then show ?case by simp + then show ?case + by simp qed qed qed - with True assms show ?thesis by (auto simp add: fold_def) + with True assms show ?thesis + by (auto simp add: fold_def) qed lemma fold_cong: assumes "comp_fun_commute f" "comp_fun_commute g" - assumes "finite A" and cong: "\x. x \ A \ f x = g x" + and "finite A" + and cong: "\x. x \ A \ f x = g x" and "s = t" and "A = B" shows "fold f s A = fold g t B" proof - - have "fold f s A = fold g s A" - using \finite A\ cong proof (induct A) - case empty then show ?case by simp + have "fold f s A = fold g s A" + using \finite A\ cong + proof (induct A) + case empty + then show ?case by simp next - case (insert x A) + case insert interpret f: comp_fun_commute f by (fact \comp_fun_commute f\) interpret g: comp_fun_commute g by (fact \comp_fun_commute g\) from insert show ?case by simp @@ -874,16 +935,19 @@ shows "fold f z (insert x A) = f x (fold f z A)" proof cases assume "x \ A" - then obtain B where "A = insert x B" and "x \ B" by (rule set_insert) - then show ?thesis using assms by (simp add: comp_fun_idem fun_left_idem) + then obtain B where "A = insert x B" and "x \ B" + by (rule set_insert) + then show ?thesis + using assms by (simp add: comp_fun_idem fun_left_idem) next - assume "x \ A" then show ?thesis using assms by simp + assume "x \ A" + then show ?thesis + using assms by simp qed declare fold_insert [simp del] fold_insert_idem [simp] -lemma fold_insert_idem2: - "finite A \ fold f z (insert x A) = fold f (f x z) A" +lemma fold_insert_idem2: "finite A \ fold f z (insert x A) = fold f (f x z) A" by (simp add: fold_fun_left_comm) end @@ -891,50 +955,54 @@ subsubsection \Liftings to \comp_fun_commute\ etc.\ -lemma (in comp_fun_commute) comp_comp_fun_commute: - "comp_fun_commute (f \ g)" -proof -qed (simp_all add: comp_fun_commute) +lemma (in comp_fun_commute) comp_comp_fun_commute: "comp_fun_commute (f \ g)" + by standard (simp_all add: comp_fun_commute) -lemma (in comp_fun_idem) comp_comp_fun_idem: - "comp_fun_idem (f \ g)" +lemma (in comp_fun_idem) comp_comp_fun_idem: "comp_fun_idem (f \ g)" by (rule comp_fun_idem.intro, rule comp_comp_fun_commute, unfold_locales) (simp_all add: comp_fun_idem) -lemma (in comp_fun_commute) comp_fun_commute_funpow: - "comp_fun_commute (\x. f x ^^ g x)" +lemma (in comp_fun_commute) comp_fun_commute_funpow: "comp_fun_commute (\x. f x ^^ g x)" proof - fix y x - show "f y ^^ g y \ f x ^^ g x = f x ^^ g x \ f y ^^ g y" + show "f y ^^ g y \ f x ^^ g x = f x ^^ g x \ f y ^^ g y" for x y proof (cases "x = y") - case True then show ?thesis by simp + case True + then show ?thesis by simp next - case False show ?thesis + case False + show ?thesis proof (induct "g x" arbitrary: g) - case 0 then show ?case by simp + case 0 + then show ?case by simp next case (Suc n g) have hyp1: "f y ^^ g y \ f x = f x \ f y ^^ g y" proof (induct "g y" arbitrary: g) - case 0 then show ?case by simp + case 0 + then show ?case by simp next case (Suc n g) define h where "h z = g z - 1" for z - with Suc have "n = h y" by simp + with Suc have "n = h y" + by simp with Suc have hyp: "f y ^^ h y \ f x = f x \ f y ^^ h y" by auto - from Suc h_def have "g y = Suc (h y)" by simp - then show ?case by (simp add: comp_assoc hyp) - (simp add: o_assoc comp_fun_commute) + from Suc h_def have "g y = Suc (h y)" + by simp + then show ?case + by (simp add: comp_assoc hyp) (simp add: o_assoc comp_fun_commute) qed define h where "h z = (if z = x then g x - 1 else g z)" for z - with Suc have "n = h x" by simp + with Suc have "n = h x" + by simp with Suc have "f y ^^ h y \ f x ^^ h x = f x ^^ h x \ f y ^^ h y" by auto - with False h_def have hyp2: "f y ^^ g y \ f x ^^ h x = f x ^^ h x \ f y ^^ g y" by simp - from Suc h_def have "g x = Suc (h x)" by simp - then show ?case by (simp del: funpow.simps add: funpow_Suc_right o_assoc hyp2) - (simp add: comp_assoc hyp1) + with False h_def have hyp2: "f y ^^ g y \ f x ^^ h x = f x ^^ h x \ f y ^^ g y" + by simp + from Suc h_def have "g x = Suc (h x)" + by simp + then show ?case + by (simp del: funpow.simps add: funpow_Suc_right o_assoc hyp2) (simp add: comp_assoc hyp1) qed qed qed @@ -942,51 +1010,45 @@ subsubsection \Expressing set operations via @{const fold}\ -lemma comp_fun_commute_const: - "comp_fun_commute (\_. f)" -proof -qed rule +lemma comp_fun_commute_const: "comp_fun_commute (\_. f)" + by standard rule -lemma comp_fun_idem_insert: - "comp_fun_idem insert" -proof -qed auto +lemma comp_fun_idem_insert: "comp_fun_idem insert" + by standard auto -lemma comp_fun_idem_remove: - "comp_fun_idem Set.remove" -proof -qed auto +lemma comp_fun_idem_remove: "comp_fun_idem Set.remove" + by standard auto -lemma (in semilattice_inf) comp_fun_idem_inf: - "comp_fun_idem inf" -proof -qed (auto simp add: inf_left_commute) +lemma (in semilattice_inf) comp_fun_idem_inf: "comp_fun_idem inf" + by standard (auto simp add: inf_left_commute) -lemma (in semilattice_sup) comp_fun_idem_sup: - "comp_fun_idem sup" -proof -qed (auto simp add: sup_left_commute) +lemma (in semilattice_sup) comp_fun_idem_sup: "comp_fun_idem sup" + by standard (auto simp add: sup_left_commute) lemma union_fold_insert: assumes "finite A" shows "A \ B = fold insert B A" proof - - interpret comp_fun_idem insert by (fact comp_fun_idem_insert) - from \finite A\ show ?thesis by (induct A arbitrary: B) simp_all + interpret comp_fun_idem insert + by (fact comp_fun_idem_insert) + from \finite A\ show ?thesis + by (induct A arbitrary: B) simp_all qed lemma minus_fold_remove: assumes "finite A" shows "B - A = fold Set.remove B A" proof - - interpret comp_fun_idem Set.remove by (fact comp_fun_idem_remove) - from \finite A\ have "fold Set.remove B A = B - A" by (induct A arbitrary: B) auto + interpret comp_fun_idem Set.remove + by (fact comp_fun_idem_remove) + from \finite A\ have "fold Set.remove B A = B - A" + by (induct A arbitrary: B) auto then show ?thesis .. qed lemma comp_fun_commute_filter_fold: "comp_fun_commute (\x A'. if P x then Set.insert x A' else A')" -proof - +proof - interpret comp_fun_idem Set.insert by (fact comp_fun_idem_insert) show ?thesis by standard (auto simp: fun_eq_iff) qed @@ -994,77 +1056,79 @@ lemma Set_filter_fold: assumes "finite A" shows "Set.filter P A = fold (\x A'. if P x then Set.insert x A' else A') {} A" -using assms -by (induct A) - (auto simp add: Set.filter_def comp_fun_commute.fold_insert[OF comp_fun_commute_filter_fold]) + using assms + by induct + (auto simp add: Set.filter_def comp_fun_commute.fold_insert[OF comp_fun_commute_filter_fold]) -lemma inter_Set_filter: +lemma inter_Set_filter: assumes "finite B" shows "A \ B = Set.filter (\x. x \ A) B" -using assms -by (induct B) (auto simp: Set.filter_def) + using assms + by induct (auto simp: Set.filter_def) lemma image_fold_insert: assumes "finite A" shows "image f A = fold (\k A. Set.insert (f k) A) {} A" -using assms proof - - interpret comp_fun_commute "\k A. Set.insert (f k) A" by standard auto - show ?thesis using assms by (induct A) auto + interpret comp_fun_commute "\k A. Set.insert (f k) A" + by standard auto + show ?thesis + using assms by (induct A) auto qed lemma Ball_fold: assumes "finite A" shows "Ball A P = fold (\k s. s \ P k) True A" -using assms proof - - interpret comp_fun_commute "\k s. s \ P k" by standard auto - show ?thesis using assms by (induct A) auto + interpret comp_fun_commute "\k s. s \ P k" + by standard auto + show ?thesis + using assms by (induct A) auto qed lemma Bex_fold: assumes "finite A" shows "Bex A P = fold (\k s. s \ P k) False A" -using assms proof - - interpret comp_fun_commute "\k s. s \ P k" by standard auto - show ?thesis using assms by (induct A) auto + interpret comp_fun_commute "\k s. s \ P k" + by standard auto + show ?thesis + using assms by (induct A) auto qed -lemma comp_fun_commute_Pow_fold: - "comp_fun_commute (\x A. A \ Set.insert x ` A)" +lemma comp_fun_commute_Pow_fold: "comp_fun_commute (\x A. A \ Set.insert x ` A)" by (clarsimp simp: fun_eq_iff comp_fun_commute_def) blast lemma Pow_fold: assumes "finite A" shows "Pow A = fold (\x A. A \ Set.insert x ` A) {{}} A" -using assms proof - - interpret comp_fun_commute "\x A. A \ Set.insert x ` A" by (rule comp_fun_commute_Pow_fold) - show ?thesis using assms by (induct A) (auto simp: Pow_insert) + interpret comp_fun_commute "\x A. A \ Set.insert x ` A" + by (rule comp_fun_commute_Pow_fold) + show ?thesis + using assms by (induct A) (auto simp: Pow_insert) qed lemma fold_union_pair: assumes "finite B" shows "(\y\B. {(x, y)}) \ A = fold (\y. Set.insert (x, y)) A B" proof - - interpret comp_fun_commute "\y. Set.insert (x, y)" by standard auto - show ?thesis using assms by (induct B arbitrary: A) simp_all + interpret comp_fun_commute "\y. Set.insert (x, y)" + by standard auto + show ?thesis + using assms by (induct arbitrary: A) simp_all qed -lemma comp_fun_commute_product_fold: - assumes "finite B" - shows "comp_fun_commute (\x z. fold (\y. Set.insert (x, y)) z B)" - by standard (auto simp: fold_union_pair[symmetric] assms) +lemma comp_fun_commute_product_fold: + "finite B \ comp_fun_commute (\x z. fold (\y. Set.insert (x, y)) z B)" + by standard (auto simp: fold_union_pair [symmetric]) lemma product_fold: - assumes "finite A" - assumes "finite B" + assumes "finite A" "finite B" shows "A \ B = fold (\x z. fold (\y. Set.insert (x, y)) z B) {} A" -using assms unfolding Sigma_def -by (induct A) - (simp_all add: comp_fun_commute.fold_insert[OF comp_fun_commute_product_fold] fold_union_pair) - + using assms unfolding Sigma_def + by (induct A) + (simp_all add: comp_fun_commute.fold_insert[OF comp_fun_commute_product_fold] fold_union_pair) context complete_lattice begin @@ -1073,61 +1137,55 @@ assumes "finite A" shows "inf (Inf A) B = fold inf B A" proof - - interpret comp_fun_idem inf by (fact comp_fun_idem_inf) - from \finite A\ fold_fun_left_comm show ?thesis by (induct A arbitrary: B) - (simp_all add: inf_commute fun_eq_iff) + interpret comp_fun_idem inf + by (fact comp_fun_idem_inf) + from \finite A\ fold_fun_left_comm show ?thesis + by (induct A arbitrary: B) (simp_all add: inf_commute fun_eq_iff) qed lemma sup_Sup_fold_sup: assumes "finite A" shows "sup (Sup A) B = fold sup B A" proof - - interpret comp_fun_idem sup by (fact comp_fun_idem_sup) - from \finite A\ fold_fun_left_comm show ?thesis by (induct A arbitrary: B) - (simp_all add: sup_commute fun_eq_iff) + interpret comp_fun_idem sup + by (fact comp_fun_idem_sup) + from \finite A\ fold_fun_left_comm show ?thesis + by (induct A arbitrary: B) (simp_all add: sup_commute fun_eq_iff) qed -lemma Inf_fold_inf: - assumes "finite A" - shows "Inf A = fold inf top A" - using assms inf_Inf_fold_inf [of A top] by (simp add: inf_absorb2) +lemma Inf_fold_inf: "finite A \ Inf A = fold inf top A" + using inf_Inf_fold_inf [of A top] by (simp add: inf_absorb2) -lemma Sup_fold_sup: - assumes "finite A" - shows "Sup A = fold sup bot A" - using assms sup_Sup_fold_sup [of A bot] by (simp add: sup_absorb2) +lemma Sup_fold_sup: "finite A \ Sup A = fold sup bot A" + using sup_Sup_fold_sup [of A bot] by (simp add: sup_absorb2) lemma inf_INF_fold_inf: assumes "finite A" - shows "inf B (INFIMUM A f) = fold (inf \ f) B A" (is "?inf = ?fold") -proof (rule sym) + shows "inf B (INFIMUM A f) = fold (inf \ f) B A" (is "?inf = ?fold") +proof - interpret comp_fun_idem inf by (fact comp_fun_idem_inf) interpret comp_fun_idem "inf \ f" by (fact comp_comp_fun_idem) - from \finite A\ show "?fold = ?inf" - by (induct A arbitrary: B) - (simp_all add: inf_left_commute) + from \finite A\ have "?fold = ?inf" + by (induct A arbitrary: B) (simp_all add: inf_left_commute) + then show ?thesis .. qed lemma sup_SUP_fold_sup: assumes "finite A" - shows "sup B (SUPREMUM A f) = fold (sup \ f) B A" (is "?sup = ?fold") -proof (rule sym) + shows "sup B (SUPREMUM A f) = fold (sup \ f) B A" (is "?sup = ?fold") +proof - interpret comp_fun_idem sup by (fact comp_fun_idem_sup) interpret comp_fun_idem "sup \ f" by (fact comp_comp_fun_idem) - from \finite A\ show "?fold = ?sup" - by (induct A arbitrary: B) - (simp_all add: sup_left_commute) + from \finite A\ have "?fold = ?sup" + by (induct A arbitrary: B) (simp_all add: sup_left_commute) + then show ?thesis .. qed -lemma INF_fold_inf: - assumes "finite A" - shows "INFIMUM A f = fold (inf \ f) top A" - using assms inf_INF_fold_inf [of A top] by simp +lemma INF_fold_inf: "finite A \ INFIMUM A f = fold (inf \ f) top A" + using inf_INF_fold_inf [of A top] by simp -lemma SUP_fold_sup: - assumes "finite A" - shows "SUPREMUM A f = fold (sup \ f) bot A" - using assms sup_SUP_fold_sup [of A bot] by simp +lemma SUP_fold_sup: "finite A \ SUPREMUM A f = fold (sup \ f) bot A" + using sup_SUP_fold_sup [of A bot] by simp end @@ -1146,15 +1204,14 @@ by standard (insert comp_fun_commute, simp add: fun_eq_iff) definition F :: "'a set \ 'b" -where - eq_fold: "F A = fold f z A" + where eq_fold: "F A = fold f z A" lemma empty [simp]:"F {} = z" by (simp add: eq_fold) lemma infinite [simp]: "\ finite A \ F A = z" by (simp add: eq_fold) - + lemma insert [simp]: assumes "finite A" and "x \ A" shows "F (insert x A) = f x (F A)" @@ -1163,7 +1220,7 @@ have "fold f z (insert x A) = f x (fold f z A)" by simp with \finite A\ show ?thesis by (simp add: eq_fold fun_eq_iff) qed - + lemma remove: assumes "finite A" and "x \ A" shows "F A = f x (F (A - {x}))" @@ -1174,10 +1231,8 @@ ultimately show ?thesis by simp qed -lemma insert_remove: - assumes "finite A" - shows "F (insert x A) = f x (F (A - {x}))" - using assms by (cases "x \ A") (simp_all add: remove insert_absorb) +lemma insert_remove: "finite A \ F (insert x A) = f x (F (A - {x}))" + by (cases "x \ A") (simp_all add: remove insert_absorb) end @@ -1209,7 +1264,7 @@ text \ The traditional definition - @{prop "card A \ LEAST n. EX f. A = {f i | i. i < n}"} + @{prop "card A \ LEAST n. \f. A = {f i |i. i < n}"} is ugly to work with. But now that we have @{const fold} things are easy: \ @@ -1218,60 +1273,49 @@ defines card = "folding.F (\_. Suc) 0" by standard rule -lemma card_infinite: - "\ finite A \ card A = 0" +lemma card_infinite: "\ finite A \ card A = 0" by (fact card.infinite) -lemma card_empty: - "card {} = 0" +lemma card_empty: "card {} = 0" by (fact card.empty) -lemma card_insert_disjoint: - "finite A \ x \ A \ card (insert x A) = Suc (card A)" +lemma card_insert_disjoint: "finite A \ x \ A \ card (insert x A) = Suc (card A)" by (fact card.insert) -lemma card_insert_if: - "finite A \ card (insert x A) = (if x \ A then card A else Suc (card A))" +lemma card_insert_if: "finite A \ card (insert x A) = (if x \ A then card A else Suc (card A))" by auto (simp add: card.insert_remove card.remove) -lemma card_ge_0_finite: - "card A > 0 \ finite A" +lemma card_ge_0_finite: "card A > 0 \ finite A" by (rule ccontr) simp -lemma card_0_eq [simp]: - "finite A \ card A = 0 \ A = {}" +lemma card_0_eq [simp]: "finite A \ card A = 0 \ A = {}" by (auto dest: mk_disjoint_insert) -lemma finite_UNIV_card_ge_0: - "finite (UNIV :: 'a set) \ card (UNIV :: 'a set) > 0" +lemma finite_UNIV_card_ge_0: "finite (UNIV :: 'a set) \ card (UNIV :: 'a set) > 0" by (rule ccontr) simp -lemma card_eq_0_iff: - "card A = 0 \ A = {} \ \ finite A" +lemma card_eq_0_iff: "card A = 0 \ A = {} \ \ finite A" by auto -lemma card_range_greater_zero: - "finite (range f) \ card (range f) > 0" +lemma card_range_greater_zero: "finite (range f) \ card (range f) > 0" by (rule ccontr) (simp add: card_eq_0_iff) -lemma card_gt_0_iff: - "0 < card A \ A \ {} \ finite A" - by (simp add: neq0_conv [symmetric] card_eq_0_iff) +lemma card_gt_0_iff: "0 < card A \ A \ {} \ finite A" + by (simp add: neq0_conv [symmetric] card_eq_0_iff) -lemma card_Suc_Diff1: - "finite A \ x \ A \ Suc (card (A - {x})) = card A" -apply(rule_tac t = A in insert_Diff [THEN subst], assumption) -apply(simp del:insert_Diff_single) -done +lemma card_Suc_Diff1: "finite A \ x \ A \ Suc (card (A - {x})) = card A" + apply (rule insert_Diff [THEN subst, where t = A]) + apply assumption + apply (simp del: insert_Diff_single) + done -lemma card_insert_le_m1: "n>0 \ card y \ n-1 \ card (insert x y) \ n" +lemma card_insert_le_m1: "n > 0 \ card y \ n - 1 \ card (insert x y) \ n" apply (cases "finite y") apply (cases "x \ y") apply (auto simp: insert_absorb) done -lemma card_Diff_singleton: - "finite A \ x \ A \ card (A - {x}) = card A - 1" +lemma card_Diff_singleton: "finite A \ x \ A \ card (A - {x}) = card A - 1" by (simp add: card_Suc_Diff1 [symmetric]) lemma card_Diff_singleton_if: @@ -1282,124 +1326,137 @@ assumes "finite A" and "a \ A" and "a \ B" shows "card (A - insert a B) = card (A - B) - 1" proof - - have "A - insert a B = (A - B) - {a}" using assms by blast - then show ?thesis using assms by(simp add: card_Diff_singleton) + have "A - insert a B = (A - B) - {a}" + using assms by blast + then show ?thesis + using assms by (simp add: card_Diff_singleton) qed -lemma card_insert: "finite A ==> card (insert x A) = Suc (card (A - {x}))" +lemma card_insert: "finite A \ card (insert x A) = Suc (card (A - {x}))" by (fact card.insert_remove) -lemma card_insert_le: "finite A ==> card A <= card (insert x A)" -by (simp add: card_insert_if) +lemma card_insert_le: "finite A \ card A \ card (insert x A)" + by (simp add: card_insert_if) -lemma card_Collect_less_nat[simp]: "card{i::nat. i < n} = n" -by (induct n) (simp_all add:less_Suc_eq Collect_disj_eq) +lemma card_Collect_less_nat[simp]: "card {i::nat. i < n} = n" + by (induct n) (simp_all add:less_Suc_eq Collect_disj_eq) -lemma card_Collect_le_nat[simp]: "card{i::nat. i <= n} = Suc n" -using card_Collect_less_nat[of "Suc n"] by(simp add: less_Suc_eq_le) +lemma card_Collect_le_nat[simp]: "card {i::nat. i \ n} = Suc n" + using card_Collect_less_nat[of "Suc n"] by (simp add: less_Suc_eq_le) lemma card_mono: assumes "finite B" and "A \ B" shows "card A \ card B" proof - - from assms have "finite A" by (auto intro: finite_subset) - then show ?thesis using assms proof (induct A arbitrary: B) - case empty then show ?case by simp + from assms have "finite A" + by (auto intro: finite_subset) + then show ?thesis + using assms + proof (induct A arbitrary: B) + case empty + then show ?case by simp next case (insert x A) - then have "x \ B" by simp - from insert have "A \ B - {x}" and "finite (B - {x})" by auto - with insert.hyps have "card A \ card (B - {x})" by auto - with \finite A\ \x \ A\ \finite B\ \x \ B\ show ?case by simp (simp only: card.remove) + then have "x \ B" + by simp + from insert have "A \ B - {x}" and "finite (B - {x})" + by auto + with insert.hyps have "card A \ card (B - {x})" + by auto + with \finite A\ \x \ A\ \finite B\ \x \ B\ show ?case + by simp (simp only: card.remove) qed qed -lemma card_seteq: "finite B ==> (!!A. A <= B ==> card B <= card A ==> A = B)" -apply (induct rule: finite_induct) -apply simp -apply clarify -apply (subgoal_tac "finite A & A - {x} <= F") - prefer 2 apply (blast intro: finite_subset, atomize) -apply (drule_tac x = "A - {x}" in spec) -apply (simp add: card_Diff_singleton_if split add: if_split_asm) -apply (case_tac "card A", auto) -done +lemma card_seteq: "finite B \ (\A. A \ B \ card B \ card A \ A = B)" + apply (induct rule: finite_induct) + apply simp + apply clarify + apply (subgoal_tac "finite A \ A - {x} \ F") + prefer 2 apply (blast intro: finite_subset, atomize) + apply (drule_tac x = "A - {x}" in spec) + apply (simp add: card_Diff_singleton_if split add: if_split_asm) + apply (case_tac "card A", auto) + done -lemma psubset_card_mono: "finite B ==> A < B ==> card A < card B" -apply (simp add: psubset_eq linorder_not_le [symmetric]) -apply (blast dest: card_seteq) -done +lemma psubset_card_mono: "finite B \ A < B \ card A < card B" + apply (simp add: psubset_eq linorder_not_le [symmetric]) + apply (blast dest: card_seteq) + done lemma card_Un_Int: - assumes "finite A" and "finite B" + assumes "finite A" "finite B" shows "card A + card B = card (A \ B) + card (A \ B)" -using assms proof (induct A) - case empty then show ?case by simp + using assms +proof (induct A) + case empty + then show ?case by simp next - case (insert x A) then show ?case + case insert + then show ?case by (auto simp add: insert_absorb Int_insert_left) qed -lemma card_Un_disjoint: - assumes "finite A" and "finite B" - assumes "A \ B = {}" - shows "card (A \ B) = card A + card B" -using assms card_Un_Int [of A B] by simp +lemma card_Un_disjoint: "finite A \ finite B \ A \ B = {} \ card (A \ B) = card A + card B" + using card_Un_Int [of A B] by simp lemma card_Un_le: "card (A \ B) \ card A + card B" -apply(cases "finite A") - apply(cases "finite B") - using le_iff_add card_Un_Int apply blast - apply simp -apply simp -done + apply (cases "finite A") + apply (cases "finite B") + using le_iff_add card_Un_Int apply blast + apply simp + apply simp + done lemma card_Diff_subset: - assumes "finite B" and "B \ A" + assumes "finite B" + and "B \ A" shows "card (A - B) = card A - card B" proof (cases "finite A") - case False with assms show ?thesis by simp + case False + with assms show ?thesis + by simp next - case True with assms show ?thesis by (induct B arbitrary: A) simp_all + case True + with assms show ?thesis + by (induct B arbitrary: A) simp_all qed lemma card_Diff_subset_Int: - assumes AB: "finite (A \ B)" shows "card (A - B) = card A - card (A \ B)" + assumes "finite (A \ B)" + shows "card (A - B) = card A - card (A \ B)" proof - have "A - B = A - A \ B" by auto - thus ?thesis - by (simp add: card_Diff_subset AB) + with assms show ?thesis + by (simp add: card_Diff_subset) qed lemma diff_card_le_card_Diff: -assumes "finite B" shows "card A - card B \ card(A - B)" -proof- + assumes "finite B" + shows "card A - card B \ card (A - B)" +proof - have "card A - card B \ card A - card (A \ B)" using card_mono[OF assms Int_lower2, of A] by arith - also have "\ = card(A-B)" using assms by(simp add: card_Diff_subset_Int) + also have "\ = card (A - B)" + using assms by (simp add: card_Diff_subset_Int) finally show ?thesis . qed -lemma card_Diff1_less: "finite A ==> x: A ==> card (A - {x}) < card A" -apply (rule Suc_less_SucD) -apply (simp add: card_Suc_Diff1 del:card_Diff_insert) -done +lemma card_Diff1_less: "finite A \ x \ A \ card (A - {x}) < card A" + by (rule Suc_less_SucD) (simp add: card_Suc_Diff1 del: card_Diff_insert) -lemma card_Diff2_less: - "finite A ==> x: A ==> y: A ==> card (A - {x} - {y}) < card A" -apply (case_tac "x = y") - apply (simp add: card_Diff1_less del:card_Diff_insert) -apply (rule less_trans) - prefer 2 apply (auto intro!: card_Diff1_less simp del:card_Diff_insert) -done +lemma card_Diff2_less: "finite A \ x \ A \ y \ A \ card (A - {x} - {y}) < card A" + apply (cases "x = y") + apply (simp add: card_Diff1_less del:card_Diff_insert) + apply (rule less_trans) + prefer 2 apply (auto intro!: card_Diff1_less simp del: card_Diff_insert) + done -lemma card_Diff1_le: "finite A ==> card (A - {x}) <= card A" -apply (case_tac "x : A") - apply (simp_all add: card_Diff1_less less_imp_le) -done +lemma card_Diff1_le: "finite A \ card (A - {x}) \ card A" + by (cases "x \ A") (simp_all add: card_Diff1_less less_imp_le) -lemma card_psubset: "finite B ==> A \ B ==> card A < card B ==> A < B" -by (erule psubsetI, blast) +lemma card_psubset: "finite B \ A \ B \ card A < card B \ A < B" + by (erule psubsetI) blast lemma card_le_inj: assumes fA: "finite A" @@ -1413,7 +1470,7 @@ next case (insert x s t) then show ?case - proof (induct rule: finite_induct[OF "insert.prems"(1)]) + proof (induct rule: finite_induct [OF insert.prems(1)]) case 1 then show ?case by simp next @@ -1454,41 +1511,43 @@ qed lemma insert_partition: - "\ x \ F; \c1 \ insert x F. \c2 \ insert x F. c1 \ c2 \ c1 \ c2 = {} \ - \ x \ \F = {}" -by auto + "x \ F \ \c1 \ insert x F. \c2 \ insert x F. c1 \ c2 \ c1 \ c2 = {} \ x \ \F = {}" + by auto -lemma finite_psubset_induct[consumes 1, case_names psubset]: - assumes fin: "finite A" - and major: "\A. finite A \ (\B. B \ A \ P B) \ P A" +lemma finite_psubset_induct [consumes 1, case_names psubset]: + assumes finite: "finite A" + and major: "\A. finite A \ (\B. B \ A \ P B) \ P A" shows "P A" -using fin + using finite proof (induct A taking: card rule: measure_induct_rule) case (less A) have fin: "finite A" by fact - have ih: "\B. \card B < card A; finite B\ \ P B" by fact - { fix B - assume asm: "B \ A" - from asm have "card B < card A" using psubset_card_mono fin by blast + have ih: "card B < card A \ finite B \ P B" for B by fact + have "P B" if "B \ A" for B + proof - + from that have "card B < card A" + using psubset_card_mono fin by blast moreover - from asm have "B \ A" by auto - then have "finite B" using fin finite_subset by blast - ultimately - have "P B" using ih by simp - } + from that have "B \ A" + by auto + then have "finite B" + using fin finite_subset by blast + ultimately show ?thesis using ih by simp + qed with fin show "P A" using major by blast qed -lemma finite_induct_select[consumes 1, case_names empty select]: +lemma finite_induct_select [consumes 1, case_names empty select]: assumes "finite S" - assumes "P {}" - assumes select: "\T. T \ S \ P T \ \s\S - T. P (insert s T)" + and "P {}" + and select: "\T. T \ S \ P T \ \s\S - T. P (insert s T)" shows "P S" proof - have "0 \ card S" by simp then have "\T \ S. card T = card S \ P T" proof (induct rule: dec_induct) - case base with \P {}\ show ?case + case base with \P {}\ + show ?case by (intro exI[of _ "{}"]) auto next case (step n) @@ -1506,24 +1565,27 @@ qed lemma remove_induct [case_names empty infinite remove]: - assumes empty: "P ({} :: 'a set)" and infinite: "\finite B \ P B" - and remove: "\A. finite A \ A \ {} \ A \ B \ (\x. x \ A \ P (A - {x})) \ P A" + assumes empty: "P ({} :: 'a set)" + and infinite: "\ finite B \ P B" + and remove: "\A. finite A \ A \ {} \ A \ B \ (\x. x \ A \ P (A - {x})) \ P A" shows "P B" proof (cases "finite B") assume "\finite B" - thus ?thesis by (rule infinite) + then show ?thesis by (rule infinite) next define A where "A = B" assume "finite B" - hence "finite A" "A \ B" by (simp_all add: A_def) - thus "P A" - proof (induction "card A" arbitrary: A) + then have "finite A" "A \ B" + by (simp_all add: A_def) + then show "P A" + proof (induct "card A" arbitrary: A) case 0 - hence "A = {}" by auto + then have "A = {}" by auto with empty show ?case by simp next case (Suc n A) - from \A \ B\ and \finite B\ have "finite A" by (rule finite_subset) + from \A \ B\ and \finite B\ have "finite A" + by (rule finite_subset) moreover from Suc.hyps have "A \ {}" by auto moreover note \A \ B\ moreover have "P (A - {x})" if x: "x \ A" for x @@ -1533,92 +1595,99 @@ qed lemma finite_remove_induct [consumes 1, case_names empty remove]: - assumes finite: "finite B" and empty: "P ({} :: 'a set)" - and rm: "\A. finite A \ A \ {} \ A \ B \ (\x. x \ A \ P (A - {x})) \ P A" + fixes P :: "'a set \ bool" + assumes finite: "finite B" + and empty: "P {}" + and rm: "\A. finite A \ A \ {} \ A \ B \ (\x. x \ A \ P (A - {x})) \ P A" defines "B' \ B" - shows "P B'" - by (induction B' rule: remove_induct) (simp_all add: assms) + shows "P B'" + by (induct B' rule: remove_induct) (simp_all add: assms) -text\main cardinality theorem\ +text \Main cardinality theorem.\ lemma card_partition [rule_format]: - "finite C ==> - finite (\C) --> - (\c\C. card c = k) --> - (\c1 \ C. \c2 \ C. c1 \ c2 --> c1 \ c2 = {}) --> - k * card(C) = card (\C)" -apply (erule finite_induct, simp) -apply (simp add: card_Un_disjoint insert_partition - finite_subset [of _ "\(insert x F)"]) -done + "finite C \ finite (\C) \ (\c\C. card c = k) \ + (\c1 \ C. \c2 \ C. c1 \ c2 \ c1 \ c2 = {}) \ + k * card C = card (\C)" + apply (induct rule: finite_induct) + apply simp + apply (simp add: card_Un_disjoint insert_partition finite_subset [of _ "\(insert x F)"]) + done lemma card_eq_UNIV_imp_eq_UNIV: assumes fin: "finite (UNIV :: 'a set)" - and card: "card A = card (UNIV :: 'a set)" + and card: "card A = card (UNIV :: 'a set)" shows "A = (UNIV :: 'a set)" proof show "A \ UNIV" by simp show "UNIV \ A" proof - fix x - show "x \ A" + show "x \ A" for x proof (rule ccontr) assume "x \ A" then have "A \ UNIV" by auto - with fin have "card A < card (UNIV :: 'a set)" by (fact psubset_card_mono) + with fin have "card A < card (UNIV :: 'a set)" + by (fact psubset_card_mono) with card show False by simp qed qed qed -text\The form of a finite set of given cardinality\ +text \The form of a finite set of given cardinality\ lemma card_eq_SucD: -assumes "card A = Suc k" -shows "\b B. A = insert b B & b \ B & card B = k & (k=0 \ B={})" + assumes "card A = Suc k" + shows "\b B. A = insert b B \ b \ B \ card B = k \ (k = 0 \ B = {})" proof - - have fin: "finite A" using assms by (auto intro: ccontr) - moreover have "card A \ 0" using assms by auto - ultimately obtain b where b: "b \ A" by auto + have fin: "finite A" + using assms by (auto intro: ccontr) + moreover have "card A \ 0" + using assms by auto + ultimately obtain b where b: "b \ A" + by auto show ?thesis proof (intro exI conjI) - show "A = insert b (A-{b})" using b by blast - show "b \ A - {b}" by blast + show "A = insert b (A - {b})" + using b by blast + show "b \ A - {b}" + by blast show "card (A - {b}) = k" and "k = 0 \ A - {b} = {}" using assms b fin by(fastforce dest:mk_disjoint_insert)+ qed qed lemma card_Suc_eq: - "(card A = Suc k) = - (\b B. A = insert b B & b \ B & card B = k & (k=0 \ B={}))" - apply(auto elim!: card_eq_SucD) - apply(subst card.insert) - apply(auto simp add: intro:ccontr) - done + "card A = Suc k \ + (\b B. A = insert b B \ b \ B \ card B = k \ (k = 0 \ B = {}))" + apply (auto elim!: card_eq_SucD) + apply (subst card.insert) + apply (auto simp add: intro:ccontr) + done lemma card_1_singletonE: - assumes "card A = 1" obtains x where "A = {x}" + assumes "card A = 1" + obtains x where "A = {x}" using assms by (auto simp: card_Suc_eq) lemma is_singleton_altdef: "is_singleton A \ card A = 1" unfolding is_singleton_def by (auto elim!: card_1_singletonE is_singletonE simp del: One_nat_def) -lemma card_le_Suc_iff: "finite A \ - Suc n \ card A = (\a B. A = insert a B \ a \ B \ n \ card B \ finite B)" -by (fastforce simp: card_Suc_eq less_eq_nat.simps(2) insert_eq_iff - dest: subset_singletonD split: nat.splits if_splits) +lemma card_le_Suc_iff: + "finite A \ Suc n \ card A = (\a B. A = insert a B \ a \ B \ n \ card B \ finite B)" + by (fastforce simp: card_Suc_eq less_eq_nat.simps(2) insert_eq_iff + dest: subset_singletonD split: nat.splits if_splits) lemma finite_fun_UNIVD2: assumes fin: "finite (UNIV :: ('a \ 'b) set)" shows "finite (UNIV :: 'b set)" proof - - from fin have "\arbitrary. finite (range (\f :: 'a \ 'b. f arbitrary))" + from fin have "finite (range (\f :: 'a \ 'b. f arbitrary))" for arbitrary by (rule finite_imageI) - moreover have "\arbitrary. UNIV = range (\f :: 'a \ 'b. f arbitrary)" + moreover have "UNIV = range (\f :: 'a \ 'b. f arbitrary)" for arbitrary by (rule UNIV_eq_I) auto - ultimately show "finite (UNIV :: 'b set)" by simp + ultimately show "finite (UNIV :: 'b set)" + by simp qed lemma card_UNIV_unit [simp]: "card (UNIV :: unit set) = 1" @@ -1628,164 +1697,176 @@ assumes "\ finite A" shows "\B. finite B \ card B = n \ B \ A" proof (induction n) - case 0 show ?case by (intro exI[of _ "{}"]) auto -next + case 0 + show ?case by (intro exI[of _ "{}"]) auto +next case (Suc n) - then guess B .. note B = this + then obtain B where B: "finite B \ card B = n \ B \ A" .. with \\ finite A\ have "A \ B" by auto with B have "B \ A" by auto - hence "\x. x \ A - B" by (elim psubset_imp_ex_mem) - then guess x .. note x = this + then have "\x. x \ A - B" + by (elim psubset_imp_ex_mem) + then obtain x where x: "x \ A - B" .. with B have "finite (insert x B) \ card (insert x B) = Suc n \ insert x B \ A" by auto - thus "\B. finite B \ card B = Suc n \ B \ A" .. + then show "\B. finite B \ card B = Suc n \ B \ A" .. qed + subsubsection \Cardinality of image\ -lemma card_image_le: "finite A ==> card (f ` A) \ card A" +lemma card_image_le: "finite A \ card (f ` A) \ card A" by (induct rule: finite_induct) (simp_all add: le_SucI card_insert_if) lemma card_image: assumes "inj_on f A" shows "card (f ` A) = card A" proof (cases "finite A") - case True then show ?thesis using assms by (induct A) simp_all + case True + then show ?thesis + using assms by (induct A) simp_all next - case False then have "\ finite (f ` A)" using assms by (auto dest: finite_imageD) - with False show ?thesis by simp + case False + then have "\ finite (f ` A)" + using assms by (auto dest: finite_imageD) + with False show ?thesis + by simp qed lemma bij_betw_same_card: "bij_betw f A B \ card A = card B" -by(auto simp: card_image bij_betw_def) + by(auto simp: card_image bij_betw_def) -lemma endo_inj_surj: "finite A ==> f ` A \ A ==> inj_on f A ==> f ` A = A" -by (simp add: card_seteq card_image) +lemma endo_inj_surj: "finite A \ f ` A \ A \ inj_on f A \ f ` A = A" + by (simp add: card_seteq card_image) lemma eq_card_imp_inj_on: - assumes "finite A" "card(f ` A) = card A" shows "inj_on f A" -using assms + assumes "finite A" "card(f ` A) = card A" + shows "inj_on f A" + using assms proof (induct rule:finite_induct) - case empty show ?case by simp + case empty + show ?case by simp next case (insert x A) - then show ?case using card_image_le [of A f] - by (simp add: card_insert_if split: if_splits) + then show ?case + using card_image_le [of A f] by (simp add: card_insert_if split: if_splits) qed -lemma inj_on_iff_eq_card: "finite A \ inj_on f A \ card(f ` A) = card A" +lemma inj_on_iff_eq_card: "finite A \ inj_on f A \ card (f ` A) = card A" by (blast intro: card_image eq_card_imp_inj_on) lemma card_inj_on_le: - assumes "inj_on f A" "f ` A \ B" "finite B" shows "card A \ card B" + assumes "inj_on f A" "f ` A \ B" "finite B" + shows "card A \ card B" proof - - have "finite A" using assms - by (blast intro: finite_imageD dest: finite_subset) - then show ?thesis using assms - by (force intro: card_mono simp: card_image [symmetric]) + have "finite A" + using assms by (blast intro: finite_imageD dest: finite_subset) + then show ?thesis + using assms by (force intro: card_mono simp: card_image [symmetric]) qed lemma surj_card_le: "finite A \ B \ f ` A \ card B \ card A" by (blast intro: card_image_le card_mono le_trans) lemma card_bij_eq: - "[|inj_on f A; f ` A \ B; inj_on g B; g ` B \ A; - finite A; finite B |] ==> card A = card B" -by (auto intro: le_antisym card_inj_on_le) + "inj_on f A \ f ` A \ B \ inj_on g B \ g ` B \ A \ finite A \ finite B + \ card A = card B" + by (auto intro: le_antisym card_inj_on_le) + +lemma bij_betw_finite: "bij_betw f A B \ finite A \ finite B" + unfolding bij_betw_def using finite_imageD [of f A] by auto -lemma bij_betw_finite: - assumes "bij_betw f A B" - shows "finite A \ finite B" -using assms unfolding bij_betw_def -using finite_imageD[of f A] by auto +lemma inj_on_finite: "inj_on f A \ f ` A \ B \ finite B \ finite A" + using finite_imageD finite_subset by blast -lemma inj_on_finite: -assumes "inj_on f A" "f ` A \ B" "finite B" -shows "finite A" -using assms finite_imageD finite_subset by blast +lemma card_vimage_inj: "inj f \ A \ range f \ card (f -` A) = card A" + by (auto 4 3 simp: subset_image_iff inj_vimage_image_eq + intro: card_image[symmetric, OF subset_inj_on]) -lemma card_vimage_inj: "\ inj f; A \ range f \ \ card (f -` A) = card A" -by(auto 4 3 simp add: subset_image_iff inj_vimage_image_eq intro: card_image[symmetric, OF subset_inj_on]) subsubsection \Pigeonhole Principles\ -lemma pigeonhole: "card A > card(f ` A) \ ~ inj_on f A " -by (auto dest: card_image less_irrefl_nat) +lemma pigeonhole: "card A > card (f ` A) \ \ inj_on f A " + by (auto dest: card_image less_irrefl_nat) lemma pigeonhole_infinite: -assumes "~ finite A" and "finite(f`A)" -shows "EX a0:A. ~finite{a:A. f a = f a0}" -proof - - have "finite(f`A) \ ~ finite A \ EX a0:A. ~finite{a:A. f a = f a0}" - proof(induct "f`A" arbitrary: A rule: finite_induct) - case empty thus ?case by simp + assumes "\ finite A" and "finite (f`A)" + shows "\a0\A. \ finite {a\A. f a = f a0}" + using assms(2,1) +proof (induct "f`A" arbitrary: A rule: finite_induct) + case empty + then show ?case by simp +next + case (insert b F) + show ?case + proof (cases "finite {a\A. f a = b}") + case True + with \\ finite A\ have "\ finite (A - {a\A. f a = b})" + by simp + also have "A - {a\A. f a = b} = {a\A. f a \ b}" + by blast + finally have "\ finite {a\A. f a \ b}" . + from insert(3)[OF _ this] insert(2,4) show ?thesis + by simp (blast intro: rev_finite_subset) next - case (insert b F) - show ?case - proof cases - assume "finite{a:A. f a = b}" - hence "~ finite(A - {a:A. f a = b})" using \\ finite A\ by simp - also have "A - {a:A. f a = b} = {a:A. f a \ b}" by blast - finally have "~ finite({a:A. f a \ b})" . - from insert(3)[OF _ this] - show ?thesis using insert(2,4) by simp (blast intro: rev_finite_subset) - next - assume 1: "~finite{a:A. f a = b}" - hence "{a \ A. f a = b} \ {}" by force - thus ?thesis using 1 by blast - qed + case False + then have "{a \ A. f a = b} \ {}" by force + with False show ?thesis by blast qed - from this[OF assms(2,1)] show ?thesis . qed lemma pigeonhole_infinite_rel: -assumes "~finite A" and "finite B" and "ALL a:A. EX b:B. R a b" -shows "EX b:B. ~finite{a:A. R a b}" + assumes "\ finite A" + and "finite B" + and "\a\A. \b\B. R a b" + shows "\b\B. \ finite {a:A. R a b}" proof - - let ?F = "%a. {b:B. R a b}" - from finite_Pow_iff[THEN iffD2, OF \finite B\] - have "finite(?F ` A)" by(blast intro: rev_finite_subset) - from pigeonhole_infinite[where f = ?F, OF assms(1) this] - obtain a0 where "a0\A" and 1: "\ finite {a\A. ?F a = ?F a0}" .. - obtain b0 where "b0 : B" and "R a0 b0" using \a0:A\ assms(3) by blast - { assume "finite{a:A. R a b0}" - then have "finite {a\A. ?F a = ?F a0}" - using \b0 : B\ \R a0 b0\ by(blast intro: rev_finite_subset) - } - with 1 \b0 : B\ show ?thesis by blast + let ?F = "\a. {b\B. R a b}" + from finite_Pow_iff[THEN iffD2, OF \finite B\] have "finite (?F ` A)" + by (blast intro: rev_finite_subset) + from pigeonhole_infinite [where f = ?F, OF assms(1) this] + obtain a0 where "a0 \ A" and 1: "\ finite {a\A. ?F a = ?F a0}" .. + obtain b0 where "b0 \ B" and "R a0 b0" + using \a0 \ A\ assms(3) by blast + have "finite {a\A. ?F a = ?F a0}" if "finite{a:A. R a b0}" + using \b0 \ B\ \R a0 b0\ that by (blast intro: rev_finite_subset) + with 1 \b0 : B\ show ?thesis + by blast qed subsubsection \Cardinality of sums\ lemma card_Plus: - assumes "finite A" and "finite B" + assumes "finite A" "finite B" shows "card (A <+> B) = card A + card B" proof - have "Inl`A \ Inr`B = {}" by fast with assms show ?thesis - unfolding Plus_def - by (simp add: card_Un_disjoint card_image) + by (simp add: Plus_def card_Un_disjoint card_image) qed lemma card_Plus_conv_if: "card (A <+> B) = (if finite A \ finite B then card A + card B else 0)" by (auto simp add: card_Plus) -text \Relates to equivalence classes. Based on a theorem of F. Kamm\"uller.\ +text \Relates to equivalence classes. Based on a theorem of F. Kammüller.\ lemma dvd_partition: - assumes f: "finite (\C)" and "\c\C. k dvd card c" "\c1\C. \c2\C. c1 \ c2 \ c1 \ c2 = {}" - shows "k dvd card (\C)" + assumes f: "finite (\C)" + and "\c\C. k dvd card c" "\c1\C. \c2\C. c1 \ c2 \ c1 \ c2 = {}" + shows "k dvd card (\C)" proof - - have "finite C" + have "finite C" by (rule finite_UnionD [OF f]) - then show ?thesis using assms + then show ?thesis + using assms proof (induct rule: finite_induct) - case empty show ?case by simp + case empty + show ?case by simp next - case (insert c C) - then show ?case + case insert + then show ?case apply simp apply (subst card_Un_disjoint) apply (auto simp add: disjoint_eq_subset_Compl) @@ -1793,34 +1874,33 @@ qed qed + subsubsection \Relating injectivity and surjectivity\ -lemma finite_surj_inj: assumes "finite A" "A \ f ` A" shows "inj_on f A" +lemma finite_surj_inj: + assumes "finite A" "A \ f ` A" + shows "inj_on f A" proof - - have "f ` A = A" + have "f ` A = A" by (rule card_seteq [THEN sym]) (auto simp add: assms card_image_le) then show ?thesis using assms by (simp add: eq_card_imp_inj_on) qed -lemma finite_UNIV_surj_inj: fixes f :: "'a \ 'a" -shows "finite(UNIV:: 'a set) \ surj f \ inj f" -by (blast intro: finite_surj_inj subset_UNIV) +lemma finite_UNIV_surj_inj: "finite(UNIV:: 'a set) \ surj f \ inj f" for f :: "'a \ 'a" + by (blast intro: finite_surj_inj subset_UNIV) -lemma finite_UNIV_inj_surj: fixes f :: "'a \ 'a" -shows "finite(UNIV:: 'a set) \ inj f \ surj f" -by(fastforce simp:surj_def dest!: endo_inj_surj) +lemma finite_UNIV_inj_surj: "finite(UNIV:: 'a set) \ inj f \ surj f" for f :: "'a \ 'a" + by (fastforce simp:surj_def dest!: endo_inj_surj) -corollary infinite_UNIV_nat [iff]: - "\ finite (UNIV :: nat set)" +corollary infinite_UNIV_nat [iff]: "\ finite (UNIV :: nat set)" proof assume "finite (UNIV :: nat set)" - with finite_UNIV_inj_surj [of Suc] - show False by simp (blast dest: Suc_neq_Zero surjD) + with finite_UNIV_inj_surj [of Suc] show False + by simp (blast dest: Suc_neq_Zero surjD) qed -lemma infinite_UNIV_char_0: - "\ finite (UNIV :: 'a::semiring_char_0 set)" +lemma infinite_UNIV_char_0: "\ finite (UNIV :: 'a::semiring_char_0 set)" proof assume "finite (UNIV :: 'a set)" with subset_UNIV have "finite (range of_nat :: 'a set)" @@ -1836,7 +1916,7 @@ hide_const (open) Finite_Set.fold -subsection "Infinite Sets" +subsection \Infinite Sets\ text \ Some elementary facts about infinite sets, mostly by Stephan Merz. @@ -1859,19 +1939,18 @@ by simp lemma Diff_infinite_finite: - assumes T: "finite T" and S: "infinite S" + assumes "finite T" "infinite S" shows "infinite (S - T)" - using T + using \finite T\ proof induct - from S - show "infinite (S - {})" by auto + from \infinite S\ show "infinite (S - {})" + by auto next fix T x assume ih: "infinite (S - T)" have "S - (insert x T) = (S - T) - {x}" by (rule Diff_insert) - with ih - show "infinite (S - (insert x T))" + with ih show "infinite (S - (insert x T))" by (simp add: infinite_remove) qed @@ -1882,21 +1961,23 @@ by simp lemma infinite_super: - assumes T: "S \ T" and S: "infinite S" + assumes "S \ T" + and "infinite S" shows "infinite T" proof assume "finite T" - with T have "finite S" by (simp add: finite_subset) - with S show False by simp + with \S \ T\ have "finite S" by (simp add: finite_subset) + with \infinite S\ show False by simp qed proposition infinite_coinduct [consumes 1, case_names infinite]: assumes "X A" - and step: "\A. X A \ \x\A. X (A - {x}) \ infinite (A - {x})" + and step: "\A. X A \ \x\A. X (A - {x}) \ infinite (A - {x})" shows "infinite A" proof assume "finite A" - then show False using \X A\ + then show False + using \X A\ proof (induction rule: finite_psubset_induct) case (psubset A) then obtain x where "x \ A" "X (A - {x}) \ infinite (A - {x})" @@ -1906,7 +1987,8 @@ show False apply (rule psubset.IH [where B = "A - {x}"]) using \x \ A\ apply blast - by (simp add: \X (A - {x})\) + apply (simp add: \X (A - {x})\) + done qed qed @@ -1918,14 +2000,14 @@ \ lemma inf_img_fin_dom': - assumes img: "finite (f ` A)" and dom: "infinite A" + assumes img: "finite (f ` A)" + and dom: "infinite A" shows "\y \ f ` A. infinite (f -` {y} \ A)" proof (rule ccontr) have "A \ (\y\f ` A. f -` {y} \ A)" by auto - moreover - assume "\ ?thesis" + moreover assume "\ ?thesis" with img have "finite (\y\f ` A. f -` {y} \ A)" by blast - ultimately have "finite A" by(rule finite_subset) + ultimately have "finite A" by (rule finite_subset) with dom show False by contradiction qed @@ -1937,16 +2019,15 @@ lemma inf_img_fin_dom: assumes img: "finite (f`A)" and dom: "infinite A" shows "\y \ f`A. infinite (f -` {y})" -using inf_img_fin_dom'[OF assms] by auto + using inf_img_fin_dom'[OF assms] by auto lemma inf_img_fin_domE: assumes "finite (f`A)" and "infinite A" obtains y where "y \ f`A" and "infinite (f -` {y})" using assms by (blast dest: inf_img_fin_dom) -proposition finite_image_absD: - fixes S :: "'a::linordered_ring set" - shows "finite (abs ` S) \ finite S" +proposition finite_image_absD: "finite (abs ` S) \ finite S" + for S :: "'a::linordered_ring set" by (rule ccontr) (auto simp: abs_eq_iff vimage_def dest: inf_img_fin_dom) end diff -r a962f349c8c9 -r a95e7432d86c src/HOL/Relation.thy --- a/src/HOL/Relation.thy Wed Jul 06 14:09:13 2016 +0200 +++ b/src/HOL/Relation.thy Wed Jul 06 20:19:51 2016 +0200 @@ -14,7 +14,7 @@ declare predicate1D [Pure.dest, dest] declare predicate2I [Pure.intro!, intro!] declare predicate2D [Pure.dest, dest] -declare bot1E [elim!] +declare bot1E [elim!] declare bot2E [elim!] declare top1I [intro!] declare top2I [intro!] @@ -56,15 +56,16 @@ subsubsection \Relations as sets of pairs\ -type_synonym 'a rel = "('a * 'a) set" +type_synonym 'a rel = "('a \ 'a) set" -lemma subrelI: \ \Version of @{thm [source] subsetI} for binary relations\ - "(\x y. (x, y) \ r \ (x, y) \ s) \ r \ s" +lemma subrelI: "(\x y. (x, y) \ r \ (x, y) \ s) \ r \ s" + \ \Version of @{thm [source] subsetI} for binary relations\ by auto -lemma lfp_induct2: \ \Version of @{thm [source] lfp_induct} for binary relations\ +lemma lfp_induct2: "(a, b) \ lfp f \ mono f \ (\a b. (a, b) \ f (lfp f \ {(x, y). P x y}) \ P a b) \ P a b" + \ \Version of @{thm [source] lfp_induct} for binary relations\ using lfp_induct_set [of "(a, b)" f "case_prod P"] by auto @@ -148,35 +149,30 @@ subsubsection \Reflexivity\ definition refl_on :: "'a set \ 'a rel \ bool" -where - "refl_on A r \ r \ A \ A \ (\x\A. (x, x) \ r)" + where "refl_on A r \ r \ A \ A \ (\x\A. (x, x) \ r)" -abbreviation refl :: "'a rel \ bool" -where \ \reflexivity over a type\ - "refl \ refl_on UNIV" +abbreviation refl :: "'a rel \ bool" \ \reflexivity over a type\ + where "refl \ refl_on UNIV" definition reflp :: "('a \ 'a \ bool) \ bool" -where - "reflp r \ (\x. r x x)" + where "reflp r \ (\x. r x x)" -lemma reflp_refl_eq [pred_set_conv]: - "reflp (\x y. (x, y) \ r) \ refl r" +lemma reflp_refl_eq [pred_set_conv]: "reflp (\x y. (x, y) \ r) \ refl r" by (simp add: refl_on_def reflp_def) -lemma refl_onI [intro?]: "r \ A \ A ==> (!!x. x : A ==> (x, x) : r) ==> refl_on A r" - by (unfold refl_on_def) (iprover intro!: ballI) +lemma refl_onI [intro?]: "r \ A \ A \ (\x. x \ A \ (x, x) \ r) \ refl_on A r" + unfolding refl_on_def by (iprover intro!: ballI) -lemma refl_onD: "refl_on A r ==> a : A ==> (a, a) : r" - by (unfold refl_on_def) blast +lemma refl_onD: "refl_on A r \ a \ A \ (a, a) \ r" + unfolding refl_on_def by blast -lemma refl_onD1: "refl_on A r ==> (x, y) : r ==> x : A" - by (unfold refl_on_def) blast +lemma refl_onD1: "refl_on A r \ (x, y) \ r \ x \ A" + unfolding refl_on_def by blast -lemma refl_onD2: "refl_on A r ==> (x, y) : r ==> y : A" - by (unfold refl_on_def) blast +lemma refl_onD2: "refl_on A r \ (x, y) \ r \ y \ A" + unfolding refl_on_def by blast -lemma reflpI [intro?]: - "(\x. r x x) \ reflp r" +lemma reflpI [intro?]: "(\x. r x x) \ reflp r" by (auto intro: refl_onI simp add: reflp_def) lemma reflpE: @@ -189,104 +185,86 @@ shows "r x x" using assms by (auto elim: reflpE) -lemma refl_on_Int: "refl_on A r ==> refl_on B s ==> refl_on (A \ B) (r \ s)" - by (unfold refl_on_def) blast +lemma refl_on_Int: "refl_on A r \ refl_on B s \ refl_on (A \ B) (r \ s)" + unfolding refl_on_def by blast -lemma reflp_inf: - "reflp r \ reflp s \ reflp (r \ s)" +lemma reflp_inf: "reflp r \ reflp s \ reflp (r \ s)" by (auto intro: reflpI elim: reflpE) -lemma refl_on_Un: "refl_on A r ==> refl_on B s ==> refl_on (A \ B) (r \ s)" - by (unfold refl_on_def) blast +lemma refl_on_Un: "refl_on A r \ refl_on B s \ refl_on (A \ B) (r \ s)" + unfolding refl_on_def by blast -lemma reflp_sup: - "reflp r \ reflp s \ reflp (r \ s)" +lemma reflp_sup: "reflp r \ reflp s \ reflp (r \ s)" by (auto intro: reflpI elim: reflpE) -lemma refl_on_INTER: - "ALL x:S. refl_on (A x) (r x) ==> refl_on (INTER S A) (INTER S r)" - by (unfold refl_on_def) fast +lemma refl_on_INTER: "\x\S. refl_on (A x) (r x) \ refl_on (INTER S A) (INTER S r)" + unfolding refl_on_def by fast -lemma refl_on_UNION: - "ALL x:S. refl_on (A x) (r x) \ refl_on (UNION S A) (UNION S r)" - by (unfold refl_on_def) blast +lemma refl_on_UNION: "\x\S. refl_on (A x) (r x) \ refl_on (UNION S A) (UNION S r)" + unfolding refl_on_def by blast lemma refl_on_empty [simp]: "refl_on {} {}" - by (simp add:refl_on_def) + by (simp add: refl_on_def) lemma refl_on_def' [nitpick_unfold, code]: "refl_on A r \ (\(x, y) \ r. x \ A \ y \ A) \ (\x \ A. (x, x) \ r)" by (auto intro: refl_onI dest: refl_onD refl_onD1 refl_onD2) lemma reflp_equality [simp]: "reflp op =" -by(simp add: reflp_def) + by (simp add: reflp_def) -lemma reflp_mono: "\ reflp R; \x y. R x y \ Q x y \ \ reflp Q" -by(auto intro: reflpI dest: reflpD) +lemma reflp_mono: "reflp R \ (\x y. R x y \ Q x y) \ reflp Q" + by (auto intro: reflpI dest: reflpD) subsubsection \Irreflexivity\ definition irrefl :: "'a rel \ bool" -where - "irrefl r \ (\a. (a, a) \ r)" + where "irrefl r \ (\a. (a, a) \ r)" definition irreflp :: "('a \ 'a \ bool) \ bool" -where - "irreflp R \ (\a. \ R a a)" + where "irreflp R \ (\a. \ R a a)" -lemma irreflp_irrefl_eq [pred_set_conv]: - "irreflp (\a b. (a, b) \ R) \ irrefl R" +lemma irreflp_irrefl_eq [pred_set_conv]: "irreflp (\a b. (a, b) \ R) \ irrefl R" by (simp add: irrefl_def irreflp_def) -lemma irreflI [intro?]: - "(\a. (a, a) \ R) \ irrefl R" +lemma irreflI [intro?]: "(\a. (a, a) \ R) \ irrefl R" by (simp add: irrefl_def) -lemma irreflpI [intro?]: - "(\a. \ R a a) \ irreflp R" +lemma irreflpI [intro?]: "(\a. \ R a a) \ irreflp R" by (fact irreflI [to_pred]) -lemma irrefl_distinct [code]: - "irrefl r \ (\(a, b) \ r. a \ b)" +lemma irrefl_distinct [code]: "irrefl r \ (\(a, b) \ r. a \ b)" by (auto simp add: irrefl_def) subsubsection \Asymmetry\ inductive asym :: "'a rel \ bool" -where - asymI: "irrefl R \ (\a b. (a, b) \ R \ (b, a) \ R) \ asym R" + where asymI: "irrefl R \ (\a b. (a, b) \ R \ (b, a) \ R) \ asym R" inductive asymp :: "('a \ 'a \ bool) \ bool" -where - asympI: "irreflp R \ (\a b. R a b \ \ R b a) \ asymp R" + where asympI: "irreflp R \ (\a b. R a b \ \ R b a) \ asymp R" -lemma asymp_asym_eq [pred_set_conv]: - "asymp (\a b. (a, b) \ R) \ asym R" +lemma asymp_asym_eq [pred_set_conv]: "asymp (\a b. (a, b) \ R) \ asym R" by (auto intro!: asymI asympI elim: asym.cases asymp.cases simp add: irreflp_irrefl_eq) subsubsection \Symmetry\ definition sym :: "'a rel \ bool" -where - "sym r \ (\x y. (x, y) \ r \ (y, x) \ r)" + where "sym r \ (\x y. (x, y) \ r \ (y, x) \ r)" definition symp :: "('a \ 'a \ bool) \ bool" -where - "symp r \ (\x y. r x y \ r y x)" + where "symp r \ (\x y. r x y \ r y x)" -lemma symp_sym_eq [pred_set_conv]: - "symp (\x y. (x, y) \ r) \ sym r" +lemma symp_sym_eq [pred_set_conv]: "symp (\x y. (x, y) \ r) \ sym r" by (simp add: sym_def symp_def) -lemma symI [intro?]: - "(\a b. (a, b) \ r \ (b, a) \ r) \ sym r" +lemma symI [intro?]: "(\a b. (a, b) \ r \ (b, a) \ r) \ sym r" by (unfold sym_def) iprover -lemma sympI [intro?]: - "(\a b. r a b \ r b a) \ symp r" +lemma sympI [intro?]: "(\a b. r a b \ r b a) \ symp r" by (fact symI [to_pred]) lemma symE: @@ -309,86 +287,70 @@ shows "r a b" using assms by (rule symD [to_pred]) -lemma sym_Int: - "sym r \ sym s \ sym (r \ s)" +lemma sym_Int: "sym r \ sym s \ sym (r \ s)" by (fast intro: symI elim: symE) -lemma symp_inf: - "symp r \ symp s \ symp (r \ s)" +lemma symp_inf: "symp r \ symp s \ symp (r \ s)" by (fact sym_Int [to_pred]) -lemma sym_Un: - "sym r \ sym s \ sym (r \ s)" +lemma sym_Un: "sym r \ sym s \ sym (r \ s)" by (fast intro: symI elim: symE) -lemma symp_sup: - "symp r \ symp s \ symp (r \ s)" +lemma symp_sup: "symp r \ symp s \ symp (r \ s)" by (fact sym_Un [to_pred]) -lemma sym_INTER: - "\x\S. sym (r x) \ sym (INTER S r)" +lemma sym_INTER: "\x\S. sym (r x) \ sym (INTER S r)" by (fast intro: symI elim: symE) -lemma symp_INF: - "\x\S. symp (r x) \ symp (INFIMUM S r)" +lemma symp_INF: "\x\S. symp (r x) \ symp (INFIMUM S r)" by (fact sym_INTER [to_pred]) -lemma sym_UNION: - "\x\S. sym (r x) \ sym (UNION S r)" +lemma sym_UNION: "\x\S. sym (r x) \ sym (UNION S r)" by (fast intro: symI elim: symE) -lemma symp_SUP: - "\x\S. symp (r x) \ symp (SUPREMUM S r)" +lemma symp_SUP: "\x\S. symp (r x) \ symp (SUPREMUM S r)" by (fact sym_UNION [to_pred]) subsubsection \Antisymmetry\ definition antisym :: "'a rel \ bool" -where - "antisym r \ (\x y. (x, y) \ r \ (y, x) \ r \ x = y)" + where "antisym r \ (\x y. (x, y) \ r \ (y, x) \ r \ x = y)" abbreviation antisymP :: "('a \ 'a \ bool) \ bool" -where -- \FIXME proper logical operation\ - "antisymP r \ antisym {(x, y). r x y}" + where "antisymP r \ antisym {(x, y). r x y}" (* FIXME proper logical operation *) + +lemma antisymI [intro?]: "(\x y. (x, y) \ r \ (y, x) \ r \ x = y) \ antisym r" + unfolding antisym_def by iprover -lemma antisymI [intro?]: - "(!!x y. (x, y) : r ==> (y, x) : r ==> x=y) ==> antisym r" - by (unfold antisym_def) iprover +lemma antisymD [dest?]: "antisym r \ (a, b) \ r \ (b, a) \ r \ a = b" + unfolding antisym_def by iprover -lemma antisymD [dest?]: "antisym r ==> (a, b) : r ==> (b, a) : r ==> a = b" - by (unfold antisym_def) iprover - -lemma antisym_subset: "r \ s ==> antisym s ==> antisym r" - by (unfold antisym_def) blast +lemma antisym_subset: "r \ s \ antisym s \ antisym r" + unfolding antisym_def by blast lemma antisym_empty [simp]: "antisym {}" - by (unfold antisym_def) blast + unfolding antisym_def by blast lemma antisymP_equality [simp]: "antisymP op =" -by(auto intro: antisymI) + by (auto intro: antisymI) subsubsection \Transitivity\ definition trans :: "'a rel \ bool" -where - "trans r \ (\x y z. (x, y) \ r \ (y, z) \ r \ (x, z) \ r)" + where "trans r \ (\x y z. (x, y) \ r \ (y, z) \ r \ (x, z) \ r)" definition transp :: "('a \ 'a \ bool) \ bool" -where - "transp r \ (\x y z. r x y \ r y z \ r x z)" + where "transp r \ (\x y z. r x y \ r y z \ r x z)" -lemma transp_trans_eq [pred_set_conv]: - "transp (\x y. (x, y) \ r) \ trans r" +lemma transp_trans_eq [pred_set_conv]: "transp (\x y. (x, y) \ r) \ trans r" by (simp add: trans_def transp_def) -lemma transI [intro?]: - "(\x y z. (x, y) \ r \ (y, z) \ r \ (x, z) \ r) \ trans r" +lemma transI [intro?]: "(\x y z. (x, y) \ r \ (y, z) \ r \ (x, z) \ r) \ trans r" by (unfold trans_def) iprover -lemma transpI [intro?]: - "(\x y z. r x y \ r y z \ r x z) \ transp r" +lemma transpI [intro?]: "(\x y z. r x y \ r y z \ r x z) \ transp r" by (fact transI [to_pred]) lemma transE: @@ -411,37 +373,31 @@ shows "r x z" using assms by (rule transD [to_pred]) -lemma trans_Int: - "trans r \ trans s \ trans (r \ s)" +lemma trans_Int: "trans r \ trans s \ trans (r \ s)" by (fast intro: transI elim: transE) -lemma transp_inf: - "transp r \ transp s \ transp (r \ s)" +lemma transp_inf: "transp r \ transp s \ transp (r \ s)" by (fact trans_Int [to_pred]) -lemma trans_INTER: - "\x\S. trans (r x) \ trans (INTER S r)" +lemma trans_INTER: "\x\S. trans (r x) \ trans (INTER S r)" by (fast intro: transI elim: transD) (* FIXME thm trans_INTER [to_pred] *) -lemma trans_join [code]: - "trans r \ (\(x, y1) \ r. \(y2, z) \ r. y1 = y2 \ (x, z) \ r)" +lemma trans_join [code]: "trans r \ (\(x, y1) \ r. \(y2, z) \ r. y1 = y2 \ (x, z) \ r)" by (auto simp add: trans_def) -lemma transp_trans: - "transp r \ trans {(x, y). r x y}" +lemma transp_trans: "transp r \ trans {(x, y). r x y}" by (simp add: trans_def transp_def) lemma transp_equality [simp]: "transp op =" -by(auto intro: transpI) + by (auto intro: transpI) subsubsection \Totality\ definition total_on :: "'a set \ 'a rel \ bool" -where - "total_on A r \ (\x\A. \y\A. x \ y \ (x, y) \ r \ (y, x) \ r)" + where "total_on A r \ (\x\A. \y\A. x \ y \ (x, y) \ r \ (y, x) \ r)" abbreviation "total \ total_on UNIV" @@ -452,27 +408,22 @@ subsubsection \Single valued relations\ definition single_valued :: "('a \ 'b) set \ bool" -where - "single_valued r \ (\x y. (x, y) \ r \ (\z. (x, z) \ r \ y = z))" + where "single_valued r \ (\x y. (x, y) \ r \ (\z. (x, z) \ r \ y = z))" abbreviation single_valuedP :: "('a \ 'b \ bool) \ bool" -where -- \FIXME proper logical operation\ - "single_valuedP r \ single_valued {(x, y). r x y}" + where "single_valuedP r \ single_valued {(x, y). r x y}" (* FIXME proper logical operation *) -lemma single_valuedI: - "ALL x y. (x,y):r --> (ALL z. (x,z):r --> y=z) ==> single_valued r" - by (unfold single_valued_def) +lemma single_valuedI: "\x y. (x, y) \ r \ (\z. (x, z) \ r \ y = z) \ single_valued r" + unfolding single_valued_def . -lemma single_valuedD: - "single_valued r ==> (x, y) : r ==> (x, z) : r ==> y = z" +lemma single_valuedD: "single_valued r \ (x, y) \ r \ (x, z) \ r \ y = z" by (simp add: single_valued_def) lemma single_valued_empty[simp]: "single_valued {}" -by(simp add: single_valued_def) + by (simp add: single_valued_def) -lemma single_valued_subset: - "r \ s ==> single_valued s ==> single_valued r" - by (unfold single_valued_def) blast +lemma single_valued_subset: "r \ s \ single_valued s \ single_valued r" + unfolding single_valued_def by blast subsection \Relation operations\ @@ -480,17 +431,16 @@ subsubsection \The identity relation\ definition Id :: "'a rel" -where - [code del]: "Id = {p. \x. p = (x, x)}" + where [code del]: "Id = {p. \x. p = (x, x)}" -lemma IdI [intro]: "(a, a) : Id" +lemma IdI [intro]: "(a, a) \ Id" by (simp add: Id_def) -lemma IdE [elim!]: "p : Id ==> (!!x. p = (x, x) ==> P) ==> P" - by (unfold Id_def) (iprover elim: CollectE) +lemma IdE [elim!]: "p \ Id \ (\x. p = (x, x) \ P) \ P" + unfolding Id_def by (iprover elim: CollectE) -lemma pair_in_Id_conv [iff]: "((a, b) : Id) = (a = b)" - by (unfold Id_def) blast +lemma pair_in_Id_conv [iff]: "(a, b) \ Id \ a = b" + unfolding Id_def by blast lemma refl_Id: "refl Id" by (simp add: refl_on_def) @@ -509,7 +459,7 @@ by (unfold single_valued_def) blast lemma irrefl_diff_Id [simp]: "irrefl (r - Id)" - by (simp add:irrefl_def) + by (simp add: irrefl_def) lemma trans_diff_Id: "trans r \ antisym r \ trans (r - Id)" unfolding antisym_def trans_def by blast @@ -524,28 +474,25 @@ subsubsection \Diagonal: identity over a set\ definition Id_on :: "'a set \ 'a rel" -where - "Id_on A = (\x\A. {(x, x)})" + where "Id_on A = (\x\A. {(x, x)})" lemma Id_on_empty [simp]: "Id_on {} = {}" - by (simp add: Id_on_def) + by (simp add: Id_on_def) -lemma Id_on_eqI: "a = b ==> a : A ==> (a, b) : Id_on A" +lemma Id_on_eqI: "a = b \ a \ A \ (a, b) \ Id_on A" by (simp add: Id_on_def) -lemma Id_onI [intro!]: "a : A ==> (a, a) : Id_on A" +lemma Id_onI [intro!]: "a \ A \ (a, a) \ Id_on A" by (rule Id_on_eqI) (rule refl) -lemma Id_onE [elim!]: - "c : Id_on A ==> (!!x. x : A ==> c = (x, x) ==> P) ==> P" +lemma Id_onE [elim!]: "c \ Id_on A \ (\x. x \ A \ c = (x, x) \ P) \ P" \ \The general elimination rule.\ - by (unfold Id_on_def) (iprover elim!: UN_E singletonE) + unfolding Id_on_def by (iprover elim!: UN_E singletonE) -lemma Id_on_iff: "((x, y) : Id_on A) = (x = y & x : A)" +lemma Id_on_iff: "(x, y) \ Id_on A \ x = y \ x \ A" by blast -lemma Id_on_def' [nitpick_unfold]: - "Id_on {x. A x} = Collect (\(x, y). x = y \ A x)" +lemma Id_on_def' [nitpick_unfold]: "Id_on {x. A x} = Collect (\(x, y). x = y \ A x)" by auto lemma Id_on_subset_Times: "Id_on A \ A \ A" @@ -555,7 +502,7 @@ by (rule refl_onI [OF Id_on_subset_Times Id_onI]) lemma antisym_Id_on [simp]: "antisym (Id_on A)" - by (unfold antisym_def) blast + unfolding antisym_def by blast lemma sym_Id_on [simp]: "sym (Id_on A)" by (rule symI) clarify @@ -564,15 +511,14 @@ by (fast intro: transI elim: transD) lemma single_valued_Id_on [simp]: "single_valued (Id_on A)" - by (unfold single_valued_def) blast + unfolding single_valued_def by blast subsubsection \Composition\ -inductive_set relcomp :: "('a \ 'b) set \ ('b \ 'c) set \ ('a \ 'c) set" (infixr "O" 75) +inductive_set relcomp :: "('a \ 'b) set \ ('b \ 'c) set \ ('a \ 'c) set" (infixr "O" 75) for r :: "('a \ 'b) set" and s :: "('b \ 'c) set" -where - relcompI [intro]: "(a, b) \ r \ (b, c) \ s \ (a, c) \ r O s" + where relcompI [intro]: "(a, b) \ r \ (b, c) \ s \ (a, c) \ r O s" notation relcompp (infixr "OO" 75) @@ -588,269 +534,239 @@ lemma relcompE [elim!]: "xz \ r O s \ (\x y z. xz = (x, z) \ (x, y) \ r \ (y, z) \ s \ P) \ P" - by (cases xz) (simp, erule relcompEpair, iprover) + apply (cases xz) + apply simp + apply (erule relcompEpair) + apply iprover + done -lemma R_O_Id [simp]: - "R O Id = R" +lemma R_O_Id [simp]: "R O Id = R" by fast -lemma Id_O_R [simp]: - "Id O R = R" +lemma Id_O_R [simp]: "Id O R = R" by fast -lemma relcomp_empty1 [simp]: - "{} O R = {}" +lemma relcomp_empty1 [simp]: "{} O R = {}" by blast -lemma relcompp_bot1 [simp]: - "\ OO R = \" +lemma relcompp_bot1 [simp]: "\ OO R = \" by (fact relcomp_empty1 [to_pred]) -lemma relcomp_empty2 [simp]: - "R O {} = {}" +lemma relcomp_empty2 [simp]: "R O {} = {}" by blast -lemma relcompp_bot2 [simp]: - "R OO \ = \" +lemma relcompp_bot2 [simp]: "R OO \ = \" by (fact relcomp_empty2 [to_pred]) -lemma O_assoc: - "(R O S) O T = R O (S O T)" +lemma O_assoc: "(R O S) O T = R O (S O T)" by blast -lemma relcompp_assoc: - "(r OO s) OO t = r OO (s OO t)" +lemma relcompp_assoc: "(r OO s) OO t = r OO (s OO t)" by (fact O_assoc [to_pred]) -lemma trans_O_subset: - "trans r \ r O r \ r" +lemma trans_O_subset: "trans r \ r O r \ r" by (unfold trans_def) blast -lemma transp_relcompp_less_eq: - "transp r \ r OO r \ r " +lemma transp_relcompp_less_eq: "transp r \ r OO r \ r " by (fact trans_O_subset [to_pred]) -lemma relcomp_mono: - "r' \ r \ s' \ s \ r' O s' \ r O s" +lemma relcomp_mono: "r' \ r \ s' \ s \ r' O s' \ r O s" by blast -lemma relcompp_mono: - "r' \ r \ s' \ s \ r' OO s' \ r OO s " +lemma relcompp_mono: "r' \ r \ s' \ s \ r' OO s' \ r OO s " by (fact relcomp_mono [to_pred]) -lemma relcomp_subset_Sigma: - "r \ A \ B \ s \ B \ C \ r O s \ A \ C" +lemma relcomp_subset_Sigma: "r \ A \ B \ s \ B \ C \ r O s \ A \ C" by blast -lemma relcomp_distrib [simp]: - "R O (S \ T) = (R O S) \ (R O T)" +lemma relcomp_distrib [simp]: "R O (S \ T) = (R O S) \ (R O T)" by auto -lemma relcompp_distrib [simp]: - "R OO (S \ T) = R OO S \ R OO T" +lemma relcompp_distrib [simp]: "R OO (S \ T) = R OO S \ R OO T" by (fact relcomp_distrib [to_pred]) -lemma relcomp_distrib2 [simp]: - "(S \ T) O R = (S O R) \ (T O R)" +lemma relcomp_distrib2 [simp]: "(S \ T) O R = (S O R) \ (T O R)" by auto -lemma relcompp_distrib2 [simp]: - "(S \ T) OO R = S OO R \ T OO R" +lemma relcompp_distrib2 [simp]: "(S \ T) OO R = S OO R \ T OO R" by (fact relcomp_distrib2 [to_pred]) -lemma relcomp_UNION_distrib: - "s O UNION I r = (\i\I. s O r i) " +lemma relcomp_UNION_distrib: "s O UNION I r = (\i\I. s O r i) " by auto (* FIXME thm relcomp_UNION_distrib [to_pred] *) -lemma relcomp_UNION_distrib2: - "UNION I r O s = (\i\I. r i O s) " +lemma relcomp_UNION_distrib2: "UNION I r O s = (\i\I. r i O s) " by auto (* FIXME thm relcomp_UNION_distrib2 [to_pred] *) -lemma single_valued_relcomp: - "single_valued r \ single_valued s \ single_valued (r O s)" - by (unfold single_valued_def) blast +lemma single_valued_relcomp: "single_valued r \ single_valued s \ single_valued (r O s)" + unfolding single_valued_def by blast -lemma relcomp_unfold: - "r O s = {(x, z). \y. (x, y) \ r \ (y, z) \ s}" +lemma relcomp_unfold: "r O s = {(x, z). \y. (x, y) \ r \ (y, z) \ s}" by (auto simp add: set_eq_iff) lemma relcompp_apply: "(R OO S) a c \ (\b. R a b \ S b c)" unfolding relcomp_unfold [to_pred] .. lemma eq_OO: "op= OO R = R" -by blast + by blast lemma OO_eq: "R OO op = = R" -by blast + by blast subsubsection \Converse\ inductive_set converse :: "('a \ 'b) set \ ('b \ 'a) set" ("(_\)" [1000] 999) for r :: "('a \ 'b) set" -where - "(a, b) \ r \ (b, a) \ r\" + where "(a, b) \ r \ (b, a) \ r\" -notation - conversep ("(_\\)" [1000] 1000) +notation conversep ("(_\\)" [1000] 1000) notation (ASCII) converse ("(_^-1)" [1000] 999) and conversep ("(_^--1)" [1000] 1000) -lemma converseI [sym]: - "(a, b) \ r \ (b, a) \ r\" +lemma converseI [sym]: "(a, b) \ r \ (b, a) \ r\" by (fact converse.intros) -lemma conversepI (* CANDIDATE [sym] *): - "r a b \ r\\ b a" +lemma conversepI (* CANDIDATE [sym] *): "r a b \ r\\ b a" by (fact conversep.intros) -lemma converseD [sym]: - "(a, b) \ r\ \ (b, a) \ r" +lemma converseD [sym]: "(a, b) \ r\ \ (b, a) \ r" by (erule converse.cases) iprover -lemma conversepD (* CANDIDATE [sym] *): - "r\\ b a \ r a b" +lemma conversepD (* CANDIDATE [sym] *): "r\\ b a \ r a b" by (fact converseD [to_pred]) -lemma converseE [elim!]: +lemma converseE [elim!]: "yx \ r\ \ (\x y. yx = (y, x) \ (x, y) \ r \ P) \ P" \ \More general than \converseD\, as it ``splits'' the member of the relation.\ - "yx \ r\ \ (\x y. yx = (y, x) \ (x, y) \ r \ P) \ P" - by (cases yx) (simp, erule converse.cases, iprover) + apply (cases yx) + apply simp + apply (erule converse.cases) + apply iprover + done lemmas conversepE [elim!] = conversep.cases -lemma converse_iff [iff]: - "(a, b) \ r\ \ (b, a) \ r" +lemma converse_iff [iff]: "(a, b) \ r\ \ (b, a) \ r" by (auto intro: converseI) -lemma conversep_iff [iff]: - "r\\ a b = r b a" +lemma conversep_iff [iff]: "r\\ a b = r b a" by (fact converse_iff [to_pred]) -lemma converse_converse [simp]: - "(r\)\ = r" +lemma converse_converse [simp]: "(r\)\ = r" by (simp add: set_eq_iff) -lemma conversep_conversep [simp]: - "(r\\)\\ = r" +lemma conversep_conversep [simp]: "(r\\)\\ = r" by (fact converse_converse [to_pred]) lemma converse_empty[simp]: "{}\ = {}" -by auto + by auto lemma converse_UNIV[simp]: "UNIV\ = UNIV" -by auto + by auto -lemma converse_relcomp: "(r O s)^-1 = s^-1 O r^-1" +lemma converse_relcomp: "(r O s)\ = s\ O r\" by blast -lemma converse_relcompp: "(r OO s)^--1 = s^--1 OO r^--1" - by (iprover intro: order_antisym conversepI relcomppI - elim: relcomppE dest: conversepD) +lemma converse_relcompp: "(r OO s)\\ = s\\ OO r\\" + by (iprover intro: order_antisym conversepI relcomppI elim: relcomppE dest: conversepD) -lemma converse_Int: "(r \ s)^-1 = r^-1 \ s^-1" +lemma converse_Int: "(r \ s)\ = r\ \ s\" by blast -lemma converse_meet: "(r \ s)^--1 = r^--1 \ s^--1" +lemma converse_meet: "(r \ s)\\ = r\\ \ s\\" by (simp add: inf_fun_def) (iprover intro: conversepI ext dest: conversepD) -lemma converse_Un: "(r \ s)^-1 = r^-1 \ s^-1" +lemma converse_Un: "(r \ s)\ = r\ \ s\" by blast -lemma converse_join: "(r \ s)^--1 = r^--1 \ s^--1" +lemma converse_join: "(r \ s)\\ = r\\ \ s\\" by (simp add: sup_fun_def) (iprover intro: conversepI ext dest: conversepD) -lemma converse_INTER: "(INTER S r)^-1 = (INT x:S. (r x)^-1)" +lemma converse_INTER: "(INTER S r)\ = (INT x:S. (r x)\)" by fast -lemma converse_UNION: "(UNION S r)^-1 = (UN x:S. (r x)^-1)" +lemma converse_UNION: "(UNION S r)\ = (UN x:S. (r x)\)" by blast -lemma converse_mono[simp]: "r^-1 \ s ^-1 \ r \ s" +lemma converse_mono[simp]: "r\ \ s \ \ r \ s" by auto -lemma conversep_mono[simp]: "r^--1 \ s ^--1 \ r \ s" +lemma conversep_mono[simp]: "r\\ \ s \\ \ r \ s" by (fact converse_mono[to_pred]) -lemma converse_inject[simp]: "r^-1 = s ^-1 \ r = s" +lemma converse_inject[simp]: "r\ = s \ \ r = s" by auto -lemma conversep_inject[simp]: "r^--1 = s ^--1 \ r = s" +lemma conversep_inject[simp]: "r\\ = s \\ \ r = s" by (fact converse_inject[to_pred]) -lemma converse_subset_swap: "r \ s ^-1 = (r ^-1 \ s)" +lemma converse_subset_swap: "r \ s \ = (r \ \ s)" by auto -lemma conversep_le_swap: "r \ s ^--1 = (r ^--1 \ s)" +lemma conversep_le_swap: "r \ s \\ = (r \\ \ s)" by (fact converse_subset_swap[to_pred]) -lemma converse_Id [simp]: "Id^-1 = Id" +lemma converse_Id [simp]: "Id\ = Id" by blast -lemma converse_Id_on [simp]: "(Id_on A)^-1 = Id_on A" +lemma converse_Id_on [simp]: "(Id_on A)\ = Id_on A" by blast lemma refl_on_converse [simp]: "refl_on A (converse r) = refl_on A r" - by (unfold refl_on_def) auto + by (auto simp: refl_on_def) lemma sym_converse [simp]: "sym (converse r) = sym r" - by (unfold sym_def) blast + unfolding sym_def by blast lemma antisym_converse [simp]: "antisym (converse r) = antisym r" - by (unfold antisym_def) blast + unfolding antisym_def by blast lemma trans_converse [simp]: "trans (converse r) = trans r" - by (unfold trans_def) blast + unfolding trans_def by blast -lemma sym_conv_converse_eq: "sym r = (r^-1 = r)" - by (unfold sym_def) fast +lemma sym_conv_converse_eq: "sym r \ r\ = r" + unfolding sym_def by fast -lemma sym_Un_converse: "sym (r \ r^-1)" - by (unfold sym_def) blast +lemma sym_Un_converse: "sym (r \ r\)" + unfolding sym_def by blast -lemma sym_Int_converse: "sym (r \ r^-1)" - by (unfold sym_def) blast +lemma sym_Int_converse: "sym (r \ r\)" + unfolding sym_def by blast -lemma total_on_converse [simp]: "total_on A (r^-1) = total_on A r" +lemma total_on_converse [simp]: "total_on A (r\) = total_on A r" by (auto simp: total_on_def) -lemma finite_converse [iff]: "finite (r^-1) = finite r" +lemma finite_converse [iff]: "finite (r\) = finite r" unfolding converse_def conversep_iff using [[simproc add: finite_Collect]] by (auto elim: finite_imageD simp: inj_on_def) -lemma conversep_noteq [simp]: "(op \)^--1 = op \" +lemma conversep_noteq [simp]: "(op \)\\ = op \" by (auto simp add: fun_eq_iff) -lemma conversep_eq [simp]: "(op =)^--1 = op =" +lemma conversep_eq [simp]: "(op =)\\ = op =" by (auto simp add: fun_eq_iff) -lemma converse_unfold [code]: - "r\ = {(y, x). (x, y) \ r}" +lemma converse_unfold [code]: "r\ = {(y, x). (x, y) \ r}" by (simp add: set_eq_iff) subsubsection \Domain, range and field\ -inductive_set Domain :: "('a \ 'b) set \ 'a set" - for r :: "('a \ 'b) set" -where - DomainI [intro]: "(a, b) \ r \ a \ Domain r" +inductive_set Domain :: "('a \ 'b) set \ 'a set" for r :: "('a \ 'b) set" + where DomainI [intro]: "(a, b) \ r \ a \ Domain r" lemmas DomainPI = Domainp.DomainI inductive_cases DomainE [elim!]: "a \ Domain r" inductive_cases DomainpE [elim!]: "Domainp r a" -inductive_set Range :: "('a \ 'b) set \ 'b set" - for r :: "('a \ 'b) set" -where - RangeI [intro]: "(a, b) \ r \ b \ Range r" +inductive_set Range :: "('a \ 'b) set \ 'b set" for r :: "('a \ 'b) set" + where RangeI [intro]: "(a, b) \ r \ b \ Range r" lemmas RangePI = Rangep.RangeI @@ -858,15 +774,12 @@ inductive_cases RangepE [elim!]: "Rangep r b" definition Field :: "'a rel \ 'a set" -where - "Field r = Domain r \ Range r" + where "Field r = Domain r \ Range r" -lemma Domain_fst [code]: - "Domain r = fst ` r" +lemma Domain_fst [code]: "Domain r = fst ` r" by force -lemma Range_snd [code]: - "Range r = snd ` r" +lemma Range_snd [code]: "Range r = snd ` r" by force lemma fst_eq_Domain: "fst ` R = Domain R" @@ -962,10 +875,10 @@ lemma Field_converse [simp]: "Field (r\) = Field r" by (auto simp: Field_def) -lemma Domain_Collect_case_prod [simp]: "Domain {(x, y). P x y} = {x. EX y. P x y}" +lemma Domain_Collect_case_prod [simp]: "Domain {(x, y). P x y} = {x. \y. P x y}" by auto -lemma Range_Collect_case_prod [simp]: "Range {(x, y). P x y} = {y. EX x. P x y}" +lemma Range_Collect_case_prod [simp]: "Range {(x, y). P x y} = {y. \x. P x y}" by auto lemma finite_Domain: "finite r \ finite (Domain r)" @@ -986,34 +899,31 @@ lemma mono_Field: "r \ s \ Field r \ Field s" by (auto simp: Field_def Domain_def Range_def) -lemma Domain_unfold: - "Domain r = {x. \y. (x, y) \ r}" +lemma Domain_unfold: "Domain r = {x. \y. (x, y) \ r}" by blast subsubsection \Image of a set under a relation\ -definition Image :: "('a \ 'b) set \ 'a set \ 'b set" (infixr "``" 90) -where - "r `` s = {y. \x\s. (x, y) \ r}" +definition Image :: "('a \ 'b) set \ 'a set \ 'b set" (infixr "``" 90) + where "r `` s = {y. \x\s. (x, y) \ r}" -lemma Image_iff: "(b : r``A) = (EX x:A. (x, b) : r)" +lemma Image_iff: "b \ r``A \ (\x\A. (x, b) \ r)" by (simp add: Image_def) -lemma Image_singleton: "r``{a} = {b. (a, b) : r}" +lemma Image_singleton: "r``{a} = {b. (a, b) \ r}" by (simp add: Image_def) -lemma Image_singleton_iff [iff]: "(b : r``{a}) = ((a, b) : r)" +lemma Image_singleton_iff [iff]: "b \ r``{a} \ (a, b) \ r" by (rule Image_iff [THEN trans]) simp -lemma ImageI [intro]: "(a, b) : r ==> a : A ==> b : r``A" - by (unfold Image_def) blast +lemma ImageI [intro]: "(a, b) \ r \ a \ A \ b \ r``A" + unfolding Image_def by blast -lemma ImageE [elim!]: - "b : r `` A ==> (!!x. (x, b) : r ==> x : A ==> P) ==> P" - by (unfold Image_def) (iprover elim!: CollectE bexE) +lemma ImageE [elim!]: "b \ r `` A \ (\x. (x, b) \ r \ x \ A \ P) \ P" + unfolding Image_def by (iprover elim!: CollectE bexE) -lemma rev_ImageI: "a : A ==> (a, b) : r ==> b : r `` A" +lemma rev_ImageI: "a \ A \ (a, b) \ r \ b \ r `` A" \ \This version's more effective when we already have the required \a\\ by blast @@ -1029,9 +939,8 @@ lemma Image_Int_subset: "R `` (A \ B) \ R `` A \ R `` B" by blast -lemma Image_Int_eq: - "single_valued (converse R) ==> R `` (A \ B) = R `` A \ R `` B" - by (simp add: single_valued_def, blast) +lemma Image_Int_eq: "single_valued (converse R) \ R `` (A \ B) = R `` A \ R `` B" + by (simp add: single_valued_def, blast) lemma Image_Un: "R `` (A \ B) = R `` A \ R `` B" by blast @@ -1039,14 +948,14 @@ lemma Un_Image: "(R \ S) `` A = R `` A \ S `` A" by blast -lemma Image_subset: "r \ A \ B ==> r``C \ B" +lemma Image_subset: "r \ A \ B \ r``C \ B" by (iprover intro!: subsetI elim!: ImageE dest!: subsetD SigmaD2) lemma Image_eq_UN: "r``B = (\y\ B. r``{y})" \ \NOT suitable for rewriting\ by blast -lemma Image_mono: "r' \ r ==> A' \ A ==> (r' `` A') \ (r `` A)" +lemma Image_mono: "r' \ r \ A' \ A \ (r' `` A') \ (r `` A)" by blast lemma Image_UN: "(r `` (UNION A B)) = (\x\A. r `` (B x))" @@ -1058,19 +967,18 @@ lemma Image_INT_subset: "(r `` INTER A B) \ (\x\A. r `` (B x))" by blast -text\Converse inclusion requires some assumptions\ -lemma Image_INT_eq: - "single_valued (r\) \ A \ {} \ r `` INTER A B = (\x\A. r `` B x)" -apply (rule equalityI) - apply (rule Image_INT_subset) -apply (auto simp add: single_valued_def) -apply blast -done +text \Converse inclusion requires some assumptions\ +lemma Image_INT_eq: "single_valued (r\) \ A \ {} \ r `` INTER A B = (\x\A. r `` B x)" + apply (rule equalityI) + apply (rule Image_INT_subset) + apply (auto simp add: single_valued_def) + apply blast + done -lemma Image_subset_eq: "(r``A \ B) = (A \ - ((r^-1) `` (-B)))" +lemma Image_subset_eq: "r``A \ B \ A \ - ((r\) `` (- B))" by blast -lemma Image_Collect_case_prod [simp]: "{(x, y). P x y} `` A = {y. EX x:A. P x y}" +lemma Image_Collect_case_prod [simp]: "{(x, y). P x y} `` A = {y. \x\A. P x y}" by auto lemma Sigma_Image: "(SIGMA x:A. B x) `` X = (\x\X \ A. B x)" @@ -1083,29 +991,27 @@ subsubsection \Inverse image\ definition inv_image :: "'b rel \ ('a \ 'b) \ 'a rel" -where - "inv_image r f = {(x, y). (f x, f y) \ r}" + where "inv_image r f = {(x, y). (f x, f y) \ r}" definition inv_imagep :: "('b \ 'b \ bool) \ ('a \ 'b) \ 'a \ 'a \ bool" -where - "inv_imagep r f = (\x y. r (f x) (f y))" + where "inv_imagep r f = (\x y. r (f x) (f y))" lemma [pred_set_conv]: "inv_imagep (\x y. (x, y) \ r) f = (\x y. (x, y) \ inv_image r f)" by (simp add: inv_image_def inv_imagep_def) -lemma sym_inv_image: "sym r ==> sym (inv_image r f)" - by (unfold sym_def inv_image_def) blast +lemma sym_inv_image: "sym r \ sym (inv_image r f)" + unfolding sym_def inv_image_def by blast -lemma trans_inv_image: "trans r ==> trans (inv_image r f)" - apply (unfold trans_def inv_image_def) +lemma trans_inv_image: "trans r \ trans (inv_image r f)" + unfolding trans_def inv_image_def apply (simp (no_asm)) apply blast done -lemma in_inv_image[simp]: "((x,y) : inv_image r f) = ((f x, f y) : r)" +lemma in_inv_image[simp]: "(x, y) \ inv_image r f \ (f x, f y) \ r" by (auto simp:inv_image_def) -lemma converse_inv_image[simp]: "(inv_image R f)^-1 = inv_image (R^-1) f" +lemma converse_inv_image[simp]: "(inv_image R f)\ = inv_image (R\) f" unfolding inv_image_def converse_unfold by auto lemma in_inv_imagep [simp]: "inv_imagep r f x y = r (f x) (f y)" @@ -1115,8 +1021,7 @@ subsubsection \Powerset\ definition Powp :: "('a \ bool) \ 'a set \ bool" -where - "Powp A = (\B. \x \ B. A x)" + where "Powp A = (\B. \x \ B. A x)" lemma Powp_Pow_eq [pred_set_conv]: "Powp (\x. x \ A) = (\x. x \ Pow A)" by (auto simp add: Powp_def fun_eq_iff) @@ -1130,28 +1035,31 @@ assumes "finite A" shows "Id_on A = Finite_Set.fold (\x. Set.insert (Pair x x)) {} A" proof - - interpret comp_fun_commute "\x. Set.insert (Pair x x)" by standard auto - show ?thesis using assms unfolding Id_on_def by (induct A) simp_all + interpret comp_fun_commute "\x. Set.insert (Pair x x)" + by standard auto + from assms show ?thesis + unfolding Id_on_def by (induct A) simp_all qed lemma comp_fun_commute_Image_fold: "comp_fun_commute (\(x,y) A. if x \ S then Set.insert y A else A)" proof - interpret comp_fun_idem Set.insert - by (fact comp_fun_idem_insert) - show ?thesis - by standard (auto simp add: fun_eq_iff comp_fun_commute split:prod.split) + by (fact comp_fun_idem_insert) + show ?thesis + by standard (auto simp add: fun_eq_iff comp_fun_commute split: prod.split) qed lemma Image_fold: assumes "finite R" shows "R `` S = Finite_Set.fold (\(x,y) A. if x \ S then Set.insert y A else A) {} R" proof - - interpret comp_fun_commute "(\(x,y) A. if x \ S then Set.insert y A else A)" + interpret comp_fun_commute "(\(x,y) A. if x \ S then Set.insert y A else A)" by (rule comp_fun_commute_Image_fold) have *: "\x F. Set.insert x F `` S = (if fst x \ S then Set.insert (snd x) (F `` S) else (F `` S))" by (force intro: rev_ImageI) - show ?thesis using assms by (induct R) (auto simp: *) + show ?thesis + using assms by (induct R) (auto simp: *) qed lemma insert_relcomp_union_fold: @@ -1159,56 +1067,56 @@ shows "{x} O S \ X = Finite_Set.fold (\(w,z) A'. if snd x = w then Set.insert (fst x,z) A' else A') X S" proof - interpret comp_fun_commute "\(w,z) A'. if snd x = w then Set.insert (fst x,z) A' else A'" - proof - - interpret comp_fun_idem Set.insert by (fact comp_fun_idem_insert) + proof - + interpret comp_fun_idem Set.insert + by (fact comp_fun_idem_insert) show "comp_fun_commute (\(w,z) A'. if snd x = w then Set.insert (fst x,z) A' else A')" - by standard (auto simp add: fun_eq_iff split:prod.split) + by standard (auto simp add: fun_eq_iff split: prod.split) qed - have *: "{x} O S = {(x', z). x' = fst x \ (snd x,z) \ S}" by (auto simp: relcomp_unfold intro!: exI) - show ?thesis unfolding * - using \finite S\ by (induct S) (auto split: prod.split) + have *: "{x} O S = {(x', z). x' = fst x \ (snd x, z) \ S}" + by (auto simp: relcomp_unfold intro!: exI) + show ?thesis + unfolding * using \finite S\ by (induct S) (auto split: prod.split) qed lemma insert_relcomp_fold: assumes "finite S" - shows "Set.insert x R O S = + shows "Set.insert x R O S = Finite_Set.fold (\(w,z) A'. if snd x = w then Set.insert (fst x,z) A' else A') (R O S) S" proof - - have "Set.insert x R O S = ({x} O S) \ (R O S)" by auto - then show ?thesis by (auto simp: insert_relcomp_union_fold[OF assms]) + have "Set.insert x R O S = ({x} O S) \ (R O S)" + by auto + then show ?thesis + by (auto simp: insert_relcomp_union_fold [OF assms]) qed lemma comp_fun_commute_relcomp_fold: assumes "finite S" - shows "comp_fun_commute (\(x,y) A. + shows "comp_fun_commute (\(x,y) A. Finite_Set.fold (\(w,z) A'. if y = w then Set.insert (x,z) A' else A') A S)" proof - - have *: "\a b A. + have *: "\a b A. Finite_Set.fold (\(w, z) A'. if b = w then Set.insert (a, z) A' else A') A S = {(a,b)} O S \ A" by (auto simp: insert_relcomp_union_fold[OF assms] cong: if_cong) - show ?thesis by standard (auto simp: *) + show ?thesis + by standard (auto simp: *) qed lemma relcomp_fold: - assumes "finite R" - assumes "finite S" - shows "R O S = Finite_Set.fold + assumes "finite R" "finite S" + shows "R O S = Finite_Set.fold (\(x,y) A. Finite_Set.fold (\(w,z) A'. if y = w then Set.insert (x,z) A' else A') A S) {} R" - using assms by (induct R) + using assms + by (induct R) (auto simp: comp_fun_commute.fold_insert comp_fun_commute_relcomp_fold insert_relcomp_fold cong: if_cong) text \Misc\ abbreviation (input) transP :: "('a \ 'a \ bool) \ bool" -where \ \FIXME drop\ - "transP r \ trans {(x, y). r x y}" + where "transP r \ trans {(x, y). r x y}" (* FIXME drop *) -abbreviation (input) - "RangeP \ Rangep" - -abbreviation (input) - "DomainP \ Domainp" - +abbreviation (input) "RangeP \ Rangep" +abbreviation (input) "DomainP \ Domainp" end diff -r a962f349c8c9 -r a95e7432d86c src/HOL/Transitive_Closure.thy --- a/src/HOL/Transitive_Closure.thy Wed Jul 06 14:09:13 2016 +0200 +++ b/src/HOL/Transitive_Closure.thy Wed Jul 06 20:19:51 2016 +0200 @@ -65,67 +65,65 @@ subsection \Reflexive closure\ -lemma refl_reflcl[simp]: "refl(r^=)" -by(simp add:refl_on_def) +lemma refl_reflcl[simp]: "refl (r\<^sup>=)" + by (simp add: refl_on_def) -lemma antisym_reflcl[simp]: "antisym(r^=) = antisym r" -by(simp add:antisym_def) +lemma antisym_reflcl[simp]: "antisym (r\<^sup>=) = antisym r" + by (simp add: antisym_def) -lemma trans_reflclI[simp]: "trans r \ trans(r^=)" -unfolding trans_def by blast +lemma trans_reflclI[simp]: "trans r \ trans (r\<^sup>=)" + unfolding trans_def by blast -lemma reflclp_idemp [simp]: "(P^==)^== = P^==" -by blast +lemma reflclp_idemp [simp]: "(P\<^sup>=\<^sup>=)\<^sup>=\<^sup>= = P\<^sup>=\<^sup>=" + by blast + subsection \Reflexive-transitive closure\ lemma reflcl_set_eq [pred_set_conv]: "(sup (\x y. (x, y) \ r) op =) = (\x y. (x, y) \ r \ Id)" by (auto simp add: fun_eq_iff) -lemma r_into_rtrancl [intro]: "!!p. p \ r ==> p \ r^*" +lemma r_into_rtrancl [intro]: "\p. p \ r \ p \ r\<^sup>*" \ \\rtrancl\ of \r\ contains \r\\ apply (simp only: split_tupled_all) apply (erule rtrancl_refl [THEN rtrancl_into_rtrancl]) done -lemma r_into_rtranclp [intro]: "r x y ==> r^** x y" +lemma r_into_rtranclp [intro]: "r x y \ r\<^sup>*\<^sup>* x y" \ \\rtrancl\ of \r\ contains \r\\ by (erule rtranclp.rtrancl_refl [THEN rtranclp.rtrancl_into_rtrancl]) -lemma rtranclp_mono: "r \ s ==> r^** \ s^**" +lemma rtranclp_mono: "r \ s \ r\<^sup>*\<^sup>* \ s\<^sup>*\<^sup>*" \ \monotonicity of \rtrancl\\ apply (rule predicate2I) apply (erule rtranclp.induct) apply (rule_tac [2] rtranclp.rtrancl_into_rtrancl, blast+) done -lemma mono_rtranclp[mono]: - "(\a b. x a b \ y a b) \ x^** a b \ y^** a b" +lemma mono_rtranclp[mono]: "(\a b. x a b \ y a b) \ x\<^sup>*\<^sup>* a b \ y\<^sup>*\<^sup>* a b" using rtranclp_mono[of x y] by auto lemmas rtrancl_mono = rtranclp_mono [to_set] theorem rtranclp_induct [consumes 1, case_names base step, induct set: rtranclp]: - assumes a: "r^** a b" - and cases: "P a" "!!y z. [| r^** a y; r y z; P y |] ==> P z" - shows "P b" using a - by (induct x\a b) (rule cases)+ + assumes a: "r\<^sup>*\<^sup>* a b" + and cases: "P a" "\y z. r\<^sup>*\<^sup>* a y \ r y z \ P y \ P z" + shows "P b" + using a by (induct x\a b) (rule cases)+ lemmas rtrancl_induct [induct set: rtrancl] = rtranclp_induct [to_set] lemmas rtranclp_induct2 = - rtranclp_induct[of _ "(ax,ay)" "(bx,by)", split_rule, - consumes 1, case_names refl step] + rtranclp_induct[of _ "(ax,ay)" "(bx,by)", split_rule, consumes 1, case_names refl step] lemmas rtrancl_induct2 = - rtrancl_induct[of "(ax,ay)" "(bx,by)", split_format (complete), - consumes 1, case_names refl step] + rtrancl_induct[of "(ax,ay)" "(bx,by)", split_format (complete), consumes 1, case_names refl step] -lemma refl_rtrancl: "refl (r^*)" -by (unfold refl_on_def) fast +lemma refl_rtrancl: "refl (r\<^sup>*)" + unfolding refl_on_def by fast text \Transitivity of transitive closure.\ -lemma trans_rtrancl: "trans (r^*)" +lemma trans_rtrancl: "trans (r\<^sup>*)" proof (rule transI) fix x y z assume "(x, y) \ r\<^sup>*" @@ -144,42 +142,40 @@ lemmas rtrancl_trans = trans_rtrancl [THEN transD] lemma rtranclp_trans: - assumes xy: "r^** x y" - and yz: "r^** y z" - shows "r^** x z" using yz xy - by induct iprover+ + assumes "r\<^sup>*\<^sup>* x y" + and "r\<^sup>*\<^sup>* y z" + shows "r\<^sup>*\<^sup>* x z" + using assms(2,1) by induct iprover+ lemma rtranclE [cases set: rtrancl]: - assumes major: "(a::'a, b) : r^*" + fixes a b :: 'a + assumes major: "(a, b) \ r\<^sup>*" obtains (base) "a = b" - | (step) y where "(a, y) : r^*" and "(y, b) : r" + | (step) y where "(a, y) \ r\<^sup>*" and "(y, b) \ r" \ \elimination of \rtrancl\ -- by induction on a special formula\ - apply (subgoal_tac "(a::'a) = b | (EX y. (a,y) : r^* & (y,b) : r)") + apply (subgoal_tac "a = b \ (\y. (a, y) \ r\<^sup>* \ (y, b) \ r)") apply (rule_tac [2] major [THEN rtrancl_induct]) prefer 2 apply blast prefer 2 apply blast apply (erule asm_rl exE disjE conjE base step)+ done -lemma rtrancl_Int_subset: "[| Id \ s; (r^* \ s) O r \ s|] ==> r^* \ s" +lemma rtrancl_Int_subset: "Id \ s \ (r\<^sup>* \ s) O r \ s \ r\<^sup>* \ s" apply (rule subsetI) apply auto apply (erule rtrancl_induct) apply auto done -lemma converse_rtranclp_into_rtranclp: - "r a b \ r\<^sup>*\<^sup>* b c \ r\<^sup>*\<^sup>* a c" +lemma converse_rtranclp_into_rtranclp: "r a b \ r\<^sup>*\<^sup>* b c \ r\<^sup>*\<^sup>* a c" by (rule rtranclp_trans) iprover+ lemmas converse_rtrancl_into_rtrancl = converse_rtranclp_into_rtranclp [to_set] -text \ - \medskip More @{term "r^*"} equations and inclusions. -\ +text \\<^medskip> More @{term "r\<^sup>*"} equations and inclusions.\ -lemma rtranclp_idemp [simp]: "(r^**)^** = r^**" +lemma rtranclp_idemp [simp]: "(r\<^sup>*\<^sup>*)\<^sup>*\<^sup>* = r\<^sup>*\<^sup>*" apply (auto intro!: order_antisym) apply (erule rtranclp_induct) apply (rule rtranclp.rtrancl_refl) @@ -188,18 +184,18 @@ lemmas rtrancl_idemp [simp] = rtranclp_idemp [to_set] -lemma rtrancl_idemp_self_comp [simp]: "R^* O R^* = R^*" +lemma rtrancl_idemp_self_comp [simp]: "R\<^sup>* O R\<^sup>* = R\<^sup>*" apply (rule set_eqI) apply (simp only: split_tupled_all) apply (blast intro: rtrancl_trans) done -lemma rtrancl_subset_rtrancl: "r \ s^* ==> r^* \ s^*" +lemma rtrancl_subset_rtrancl: "r \ s\<^sup>* \ r\<^sup>* \ s\<^sup>*" apply (drule rtrancl_mono) apply simp done -lemma rtranclp_subset: "R \ S ==> S \ R^** ==> S^** = R^**" +lemma rtranclp_subset: "R \ S \ S \ R\<^sup>*\<^sup>* \ S\<^sup>*\<^sup>* = R\<^sup>*\<^sup>*" apply (drule rtranclp_mono) apply (drule rtranclp_mono) apply simp @@ -207,17 +203,17 @@ lemmas rtrancl_subset = rtranclp_subset [to_set] -lemma rtranclp_sup_rtranclp: "(sup (R^**) (S^**))^** = (sup R S)^**" -by (blast intro!: rtranclp_subset intro: rtranclp_mono [THEN predicate2D]) +lemma rtranclp_sup_rtranclp: "(sup (R\<^sup>*\<^sup>*) (S\<^sup>*\<^sup>*))\<^sup>*\<^sup>* = (sup R S)\<^sup>*\<^sup>*" + by (blast intro!: rtranclp_subset intro: rtranclp_mono [THEN predicate2D]) lemmas rtrancl_Un_rtrancl = rtranclp_sup_rtranclp [to_set] -lemma rtranclp_reflclp [simp]: "(R^==)^** = R^**" -by (blast intro!: rtranclp_subset) +lemma rtranclp_reflclp [simp]: "(R\<^sup>=\<^sup>=)\<^sup>*\<^sup>* = R\<^sup>*\<^sup>*" + by (blast intro!: rtranclp_subset) lemmas rtrancl_reflcl [simp] = rtranclp_reflclp [to_set] -lemma rtrancl_r_diff_Id: "(r - Id)^* = r^*" +lemma rtrancl_r_diff_Id: "(r - Id)\<^sup>* = r\<^sup>*" apply (rule sym) apply (rule rtrancl_subset, blast, clarify) apply (rename_tac a b) @@ -226,39 +222,35 @@ apply blast done -lemma rtranclp_r_diff_Id: "(inf r op ~=)^** = r^**" +lemma rtranclp_r_diff_Id: "(inf r op \)\<^sup>*\<^sup>* = r\<^sup>*\<^sup>*" apply (rule sym) apply (rule rtranclp_subset) apply blast+ done theorem rtranclp_converseD: - assumes r: "(r^--1)^** x y" - shows "r^** y x" -proof - - from r show ?thesis - by induct (iprover intro: rtranclp_trans dest!: conversepD)+ -qed + assumes "(r\\)\<^sup>*\<^sup>* x y" + shows "r\<^sup>*\<^sup>* y x" + using assms by induct (iprover intro: rtranclp_trans dest!: conversepD)+ lemmas rtrancl_converseD = rtranclp_converseD [to_set] theorem rtranclp_converseI: - assumes "r^** y x" - shows "(r^--1)^** x y" - using assms - by induct (iprover intro: rtranclp_trans conversepI)+ + assumes "r\<^sup>*\<^sup>* y x" + shows "(r\\)\<^sup>*\<^sup>* x y" + using assms by induct (iprover intro: rtranclp_trans conversepI)+ lemmas rtrancl_converseI = rtranclp_converseI [to_set] -lemma rtrancl_converse: "(r^-1)^* = (r^*)^-1" +lemma rtrancl_converse: "(r^-1)\<^sup>* = (r\<^sup>*)^-1" by (fast dest!: rtrancl_converseD intro!: rtrancl_converseI) -lemma sym_rtrancl: "sym r ==> sym (r^*)" +lemma sym_rtrancl: "sym r \ sym (r\<^sup>*)" by (simp only: sym_conv_converse_eq rtrancl_converse [symmetric]) theorem converse_rtranclp_induct [consumes 1, case_names base step]: - assumes major: "r^** a b" - and cases: "P b" "!!y z. [| r y z; r^** z b; P z |] ==> P y" + assumes major: "r\<^sup>*\<^sup>* a b" + and cases: "P b" "\y z. r y z \ r\<^sup>*\<^sup>* z b \ P z \ P y" shows "P a" using rtranclp_converseI [OF major] by induct (iprover intro: cases dest!: conversepD rtranclp_converseD)+ @@ -266,19 +258,17 @@ lemmas converse_rtrancl_induct = converse_rtranclp_induct [to_set] lemmas converse_rtranclp_induct2 = - converse_rtranclp_induct [of _ "(ax,ay)" "(bx,by)", split_rule, - consumes 1, case_names refl step] + converse_rtranclp_induct [of _ "(ax,ay)" "(bx,by)", split_rule, consumes 1, case_names refl step] lemmas converse_rtrancl_induct2 = converse_rtrancl_induct [of "(ax,ay)" "(bx,by)", split_format (complete), - consumes 1, case_names refl step] + consumes 1, case_names refl step] lemma converse_rtranclpE [consumes 1, case_names base step]: - assumes major: "r^** x z" - and cases: "x=z ==> P" - "!!y. [| r x y; r^** y z |] ==> P" + assumes major: "r\<^sup>*\<^sup>* x z" + and cases: "x = z \ P" "\y. r x y \ r\<^sup>*\<^sup>* y z \ P" shows P - apply (subgoal_tac "x = z | (EX y. r x y & r^** y z)") + apply (subgoal_tac "x = z \ (\y. r x y \ r\<^sup>*\<^sup>* y z)") apply (rule_tac [2] major [THEN converse_rtranclp_induct]) prefer 2 apply iprover prefer 2 apply iprover @@ -291,41 +281,42 @@ lemmas converse_rtranclE2 = converse_rtranclE [of "(xa,xb)" "(za,zb)", split_rule] -lemma r_comp_rtrancl_eq: "r O r^* = r^* O r" +lemma r_comp_rtrancl_eq: "r O r\<^sup>* = r\<^sup>* O r" by (blast elim: rtranclE converse_rtranclE intro: rtrancl_into_rtrancl converse_rtrancl_into_rtrancl) -lemma rtrancl_unfold: "r^* = Id Un r^* O r" +lemma rtrancl_unfold: "r\<^sup>* = Id \ r\<^sup>* O r" by (auto intro: rtrancl_into_rtrancl elim: rtranclE) lemma rtrancl_Un_separatorE: - "(a,b) : (P \ Q)^* \ \x y. (a,x) : P^* \ (x,y) : Q \ x=y \ (a,b) : P^*" -apply (induct rule:rtrancl.induct) - apply blast -apply (blast intro:rtrancl_trans) -done + "(a, b) \ (P \ Q)\<^sup>* \ \x y. (a, x) \ P\<^sup>* \ (x, y) \ Q \ x = y \ (a, b) \ P\<^sup>*" + apply (induct rule:rtrancl.induct) + apply blast + apply (blast intro:rtrancl_trans) + done lemma rtrancl_Un_separator_converseE: - "(a,b) : (P \ Q)^* \ \x y. (x,b) : P^* \ (y,x) : Q \ y=x \ (a,b) : P^*" -apply (induct rule:converse_rtrancl_induct) - apply blast -apply (blast intro:rtrancl_trans) -done + "(a, b) \ (P \ Q)\<^sup>* \ \x y. (x, b) \ P\<^sup>* \ (y, x) \ Q \ y = x \ (a, b) \ P\<^sup>*" + apply (induct rule:converse_rtrancl_induct) + apply blast + apply (blast intro:rtrancl_trans) + done lemma Image_closed_trancl: - assumes "r `` X \ X" shows "r\<^sup>* `` X = X" + assumes "r `` X \ X" + shows "r\<^sup>* `` X = X" proof - - from assms have **: "{y. \x\X. (x, y) \ r} \ X" by auto - have "\x y. (y, x) \ r\<^sup>* \ y \ X \ x \ X" + from assms have **: "{y. \x\X. (x, y) \ r} \ X" + by auto + have "x \ X" if 1: "(y, x) \ r\<^sup>*" and 2: "y \ X" for x y proof - - fix x y - assume *: "y \ X" - assume "(y, x) \ r\<^sup>*" - then show "x \ X" + from 1 show "x \ X" proof induct - case base show ?case by (fact *) + case base + show ?case by (fact 2) next - case step with ** show ?case by auto + case step + with ** show ?case by auto qed qed then show ?thesis by auto @@ -334,31 +325,30 @@ subsection \Transitive closure\ -lemma trancl_mono: "!!p. p \ r^+ ==> r \ s ==> p \ s^+" +lemma trancl_mono: "\p. p \ r\<^sup>+ \ r \ s \ p \ s\<^sup>+" apply (simp add: split_tupled_all) apply (erule trancl.induct) apply (iprover dest: subsetD)+ done -lemma r_into_trancl': "!!p. p : r ==> p : r^+" +lemma r_into_trancl': "\p. p \ r \ p \ r\<^sup>+" by (simp only: split_tupled_all) (erule r_into_trancl) -text \ - \medskip Conversions between \trancl\ and \rtrancl\. -\ +text \\<^medskip> Conversions between \trancl\ and \rtrancl\.\ -lemma tranclp_into_rtranclp: "r^++ a b ==> r^** a b" +lemma tranclp_into_rtranclp: "r\<^sup>+\<^sup>+ a b \ r\<^sup>*\<^sup>* a b" by (erule tranclp.induct) iprover+ lemmas trancl_into_rtrancl = tranclp_into_rtranclp [to_set] -lemma rtranclp_into_tranclp1: assumes r: "r^** a b" - shows "!!c. r b c ==> r^++ a c" using r - by induct iprover+ +lemma rtranclp_into_tranclp1: + assumes "r\<^sup>*\<^sup>* a b" + shows "r b c \ r\<^sup>+\<^sup>+ a c" + using assms by (induct arbitrary: c) iprover+ lemmas rtrancl_into_trancl1 = rtranclp_into_tranclp1 [to_set] -lemma rtranclp_into_tranclp2: "[| r a b; r^** b c |] ==> r^++ a c" +lemma rtranclp_into_tranclp2: "r a b \ r\<^sup>*\<^sup>* b c \ r\<^sup>+\<^sup>+ a c" \ \intro rule from \r\ and \rtrancl\\ apply (erule rtranclp.cases) apply iprover @@ -370,26 +360,23 @@ text \Nice induction rule for \trancl\\ lemma tranclp_induct [consumes 1, case_names base step, induct pred: tranclp]: - assumes a: "r^++ a b" - and cases: "!!y. r a y ==> P y" - "!!y z. r^++ a y ==> r y z ==> P y ==> P z" - shows "P b" using a - by (induct x\a b) (iprover intro: cases)+ + assumes a: "r\<^sup>+\<^sup>+ a b" + and cases: "\y. r a y \ P y" "\y z. r\<^sup>+\<^sup>+ a y \ r y z \ P y \ P z" + shows "P b" + using a by (induct x\a b) (iprover intro: cases)+ lemmas trancl_induct [induct set: trancl] = tranclp_induct [to_set] lemmas tranclp_induct2 = - tranclp_induct [of _ "(ax,ay)" "(bx,by)", split_rule, - consumes 1, case_names base step] + tranclp_induct [of _ "(ax,ay)" "(bx,by)", split_rule, consumes 1, case_names base step] lemmas trancl_induct2 = trancl_induct [of "(ax,ay)" "(bx,by)", split_format (complete), consumes 1, case_names base step] lemma tranclp_trans_induct: - assumes major: "r^++ x y" - and cases: "!!x y. r x y ==> P x y" - "!!x y z. [| r^++ x y; P x y; r^++ y z; P y z |] ==> P x z" + assumes major: "r\<^sup>+\<^sup>+ x y" + and cases: "\x y. r x y \ P x y" "\x y z. r\<^sup>+\<^sup>+ x y \ P x y \ r\<^sup>+\<^sup>+ y z \ P y z \ P x z" shows "P x y" \ \Another induction rule for trancl, incorporating transitivity\ by (iprover intro: major [THEN tranclp_induct] cases) @@ -397,49 +384,49 @@ lemmas trancl_trans_induct = tranclp_trans_induct [to_set] lemma tranclE [cases set: trancl]: - assumes "(a, b) : r^+" + assumes "(a, b) \ r\<^sup>+" obtains - (base) "(a, b) : r" - | (step) c where "(a, c) : r^+" and "(c, b) : r" + (base) "(a, b) \ r" + | (step) c where "(a, c) \ r\<^sup>+" and "(c, b) \ r" using assms by cases simp_all -lemma trancl_Int_subset: "[| r \ s; (r^+ \ s) O r \ s|] ==> r^+ \ s" +lemma trancl_Int_subset: "r \ s \ (r\<^sup>+ \ s) O r \ s \ r\<^sup>+ \ s" apply (rule subsetI) apply auto apply (erule trancl_induct) apply auto done -lemma trancl_unfold: "r^+ = r Un r^+ O r" +lemma trancl_unfold: "r\<^sup>+ = r \ r\<^sup>+ O r" by (auto intro: trancl_into_trancl elim: tranclE) -text \Transitivity of @{term "r^+"}\ -lemma trans_trancl [simp]: "trans (r^+)" +text \Transitivity of @{term "r\<^sup>+"}\ +lemma trans_trancl [simp]: "trans (r\<^sup>+)" proof (rule transI) fix x y z - assume "(x, y) \ r^+" - assume "(y, z) \ r^+" - then show "(x, z) \ r^+" + assume "(x, y) \ r\<^sup>+" + assume "(y, z) \ r\<^sup>+" + then show "(x, z) \ r\<^sup>+" proof induct case (base u) - from \(x, y) \ r^+\ and \(y, u) \ r\ - show "(x, u) \ r^+" .. + from \(x, y) \ r\<^sup>+\ and \(y, u) \ r\ + show "(x, u) \ r\<^sup>+" .. next case (step u v) - from \(x, u) \ r^+\ and \(u, v) \ r\ - show "(x, v) \ r^+" .. + from \(x, u) \ r\<^sup>+\ and \(u, v) \ r\ + show "(x, v) \ r\<^sup>+" .. qed qed lemmas trancl_trans = trans_trancl [THEN transD] lemma tranclp_trans: - assumes xy: "r^++ x y" - and yz: "r^++ y z" - shows "r^++ x z" using yz xy - by induct iprover+ + assumes "r\<^sup>+\<^sup>+ x y" + and "r\<^sup>+\<^sup>+ y z" + shows "r\<^sup>+\<^sup>+ x z" + using assms(2,1) by induct iprover+ -lemma trancl_id [simp]: "trans r \ r^+ = r" +lemma trancl_id [simp]: "trans r \ r\<^sup>+ = r" apply auto apply (erule trancl_induct) apply assumption @@ -448,18 +435,18 @@ done lemma rtranclp_tranclp_tranclp: - assumes "r^** x y" - shows "!!z. r^++ y z ==> r^++ x z" using assms - by induct (iprover intro: tranclp_trans)+ + assumes "r\<^sup>*\<^sup>* x y" + shows "\z. r\<^sup>+\<^sup>+ y z \ r\<^sup>+\<^sup>+ x z" + using assms by induct (iprover intro: tranclp_trans)+ lemmas rtrancl_trancl_trancl = rtranclp_tranclp_tranclp [to_set] -lemma tranclp_into_tranclp2: "r a b ==> r^++ b c ==> r^++ a c" +lemma tranclp_into_tranclp2: "r a b \ r\<^sup>+\<^sup>+ b c \ r\<^sup>+\<^sup>+ a c" by (erule tranclp_trans [OF tranclp.r_into_trancl]) lemmas trancl_into_trancl2 = tranclp_into_tranclp2 [to_set] -lemma tranclp_converseI: "(r^++)^--1 x y ==> (r^--1)^++ x y" +lemma tranclp_converseI: "(r\<^sup>+\<^sup>+)\\ x y \ (r\\)\<^sup>+\<^sup>+ x y" apply (drule conversepD) apply (erule tranclp_induct) apply (iprover intro: conversepI tranclp_trans)+ @@ -467,7 +454,7 @@ lemmas trancl_converseI = tranclp_converseI [to_set] -lemma tranclp_converseD: "(r^--1)^++ x y ==> (r^++)^--1 x y" +lemma tranclp_converseD: "(r\\)\<^sup>+\<^sup>+ x y \ (r\<^sup>+\<^sup>+)\\ x y" apply (rule conversepI) apply (erule tranclp_induct) apply (iprover dest: conversepD intro: tranclp_trans)+ @@ -475,19 +462,17 @@ lemmas trancl_converseD = tranclp_converseD [to_set] -lemma tranclp_converse: "(r^--1)^++ = (r^++)^--1" - by (fastforce simp add: fun_eq_iff - intro!: tranclp_converseI dest!: tranclp_converseD) +lemma tranclp_converse: "(r\\)\<^sup>+\<^sup>+ = (r\<^sup>+\<^sup>+)\\" + by (fastforce simp add: fun_eq_iff intro!: tranclp_converseI dest!: tranclp_converseD) lemmas trancl_converse = tranclp_converse [to_set] -lemma sym_trancl: "sym r ==> sym (r^+)" +lemma sym_trancl: "sym r \ sym (r\<^sup>+)" by (simp only: sym_conv_converse_eq trancl_converse [symmetric]) lemma converse_tranclp_induct [consumes 1, case_names base step]: - assumes major: "r^++ a b" - and cases: "!!y. r y b ==> P(y)" - "!!y z.[| r y z; r^++ z b; P(z) |] ==> P(y)" + assumes major: "r\<^sup>+\<^sup>+ a b" + and cases: "\y. r y b \ P y" "\y z. r y z \ r\<^sup>+\<^sup>+ z b \ P z \ P y" shows "P a" apply (rule tranclp_induct [OF tranclp_converseI, OF conversepI, OF major]) apply (rule cases) @@ -497,7 +482,7 @@ lemmas converse_trancl_induct = converse_tranclp_induct [to_set] -lemma tranclpD: "R^++ x y ==> EX z. R x z \ R^** z y" +lemma tranclpD: "R\<^sup>+\<^sup>+ x y \ \z. R x z \ R\<^sup>*\<^sup>* z y" apply (erule converse_tranclp_induct) apply auto apply (blast intro: rtranclp_trans) @@ -507,48 +492,48 @@ lemma converse_tranclpE: assumes major: "tranclp r x z" - assumes base: "r x z ==> P" - assumes step: "\ y. [| r x y; tranclp r y z |] ==> P" + and base: "r x z \ P" + and step: "\ y. r x y \ tranclp r y z \ P" shows P proof - - from tranclpD[OF major] - obtain y where "r x y" and "rtranclp r y z" by iprover + from tranclpD [OF major] obtain y where "r x y" and "rtranclp r y z" + by iprover from this(2) show P proof (cases rule: rtranclp.cases) case rtrancl_refl - with \r x y\ base show P by iprover + with \r x y\ base show P + by iprover next case rtrancl_into_rtrancl from this have "tranclp r y z" by (iprover intro: rtranclp_into_tranclp1) - with \r x y\ step show P by iprover + with \r x y\ step show P + by iprover qed qed lemmas converse_tranclE = converse_tranclpE [to_set] -lemma tranclD2: - "(x, y) \ R\<^sup>+ \ \z. (x, z) \ R\<^sup>* \ (z, y) \ R" +lemma tranclD2: "(x, y) \ R\<^sup>+ \ \z. (x, z) \ R\<^sup>* \ (z, y) \ R" by (blast elim: tranclE intro: trancl_into_rtrancl) -lemma irrefl_tranclI: "r^-1 \ r^* = {} ==> (x, x) \ r^+" +lemma irrefl_tranclI: "r\ \ r\<^sup>* = {} \ (x, x) \ r\<^sup>+" by (blast elim: tranclE dest: trancl_into_rtrancl) -lemma irrefl_trancl_rD: "\x. (x, x) \ r^+ \ (x, y) \ r \ x \ y" +lemma irrefl_trancl_rD: "\x. (x, x) \ r\<^sup>+ \ (x, y) \ r \ x \ y" by (blast dest: r_into_trancl) -lemma trancl_subset_Sigma_aux: - "(a, b) \ r^* ==> r \ A \ A ==> a = b \ a \ A" +lemma trancl_subset_Sigma_aux: "(a, b) \ r\<^sup>* \ r \ A \ A \ a = b \ a \ A" by (induct rule: rtrancl_induct) auto -lemma trancl_subset_Sigma: "r \ A \ A ==> r^+ \ A \ A" +lemma trancl_subset_Sigma: "r \ A \ A \ r\<^sup>+ \ A \ A" apply (rule subsetI) apply (simp only: split_tupled_all) apply (erule tranclE) apply (blast dest!: trancl_into_rtrancl trancl_subset_Sigma_aux)+ done -lemma reflclp_tranclp [simp]: "(r^++)^== = r^**" +lemma reflclp_tranclp [simp]: "(r\<^sup>+\<^sup>+)\<^sup>=\<^sup>= = r\<^sup>*\<^sup>*" apply (safe intro!: order_antisym) apply (erule tranclp_into_rtranclp) apply (blast elim: rtranclp.cases dest: rtranclp_into_tranclp1) @@ -556,7 +541,7 @@ lemmas reflcl_trancl [simp] = reflclp_tranclp [to_set] -lemma trancl_reflcl [simp]: "(r^=)^+ = r^*" +lemma trancl_reflcl [simp]: "(r\<^sup>=)\<^sup>+ = r\<^sup>*" apply safe apply (drule trancl_into_rtrancl, simp) apply (erule rtranclE, safe) @@ -565,32 +550,30 @@ apply (erule rtrancl_reflcl [THEN equalityD2, THEN subsetD], fast) done -lemma rtrancl_trancl_reflcl [code]: "r^* = (r^+)^=" +lemma rtrancl_trancl_reflcl [code]: "r\<^sup>* = (r\<^sup>+)\<^sup>=" by simp -lemma trancl_empty [simp]: "{}^+ = {}" +lemma trancl_empty [simp]: "{}\<^sup>+ = {}" by (auto elim: trancl_induct) -lemma rtrancl_empty [simp]: "{}^* = Id" +lemma rtrancl_empty [simp]: "{}\<^sup>* = Id" by (rule subst [OF reflcl_trancl]) simp -lemma rtranclpD: "R^** a b ==> a = b \ a \ b \ R^++ a b" -by (force simp add: reflclp_tranclp [symmetric] simp del: reflclp_tranclp) +lemma rtranclpD: "R\<^sup>*\<^sup>* a b \ a = b \ a \ b \ R\<^sup>+\<^sup>+ a b" + by (force simp add: reflclp_tranclp [symmetric] simp del: reflclp_tranclp) lemmas rtranclD = rtranclpD [to_set] -lemma rtrancl_eq_or_trancl: - "(x,y) \ R\<^sup>* = (x=y \ x\y \ (x,y) \ R\<^sup>+)" +lemma rtrancl_eq_or_trancl: "(x,y) \ R\<^sup>* \ x = y \ x \ y \ (x, y) \ R\<^sup>+" by (fast elim: trancl_into_rtrancl dest: rtranclD) -lemma trancl_unfold_right: "r^+ = r^* O r" -by (auto dest: tranclD2 intro: rtrancl_into_trancl1) +lemma trancl_unfold_right: "r\<^sup>+ = r\<^sup>* O r" + by (auto dest: tranclD2 intro: rtrancl_into_trancl1) -lemma trancl_unfold_left: "r^+ = r O r^*" -by (auto dest: tranclD intro: rtrancl_into_trancl2) +lemma trancl_unfold_left: "r\<^sup>+ = r O r\<^sup>*" + by (auto dest: tranclD intro: rtrancl_into_trancl2) -lemma trancl_insert: - "(insert (y, x) r)^+ = r^+ \ {(a, b). (a, y) \ r^* \ (x, b) \ r^*}" +lemma trancl_insert: "(insert (y, x) r)\<^sup>+ = r\<^sup>+ \ {(a, b). (a, y) \ r\<^sup>* \ (x, b) \ r\<^sup>*}" \ \primitive recursion for \trancl\ over finite relations\ apply (rule equalityI) apply (rule subsetI) @@ -603,62 +586,60 @@ done lemma trancl_insert2: - "(insert (a,b) r)^+ = r^+ \ {(x,y). ((x,a) : r^+ \ x=a) \ ((b,y) \ r^+ \ y=b)}" -by(auto simp add: trancl_insert rtrancl_eq_or_trancl) + "(insert (a, b) r)\<^sup>+ = r\<^sup>+ \ {(x, y). ((x, a) \ r\<^sup>+ \ x = a) \ ((b, y) \ r\<^sup>+ \ y = b)}" + by (auto simp add: trancl_insert rtrancl_eq_or_trancl) -lemma rtrancl_insert: - "(insert (a,b) r)^* = r^* \ {(x,y). (x,a) : r^* \ (b,y) \ r^*}" -using trancl_insert[of a b r] -by(simp add: rtrancl_trancl_reflcl del: reflcl_trancl) blast +lemma rtrancl_insert: "(insert (a,b) r)\<^sup>* = r\<^sup>* \ {(x, y). (x, a) \ r\<^sup>* \ (b, y) \ r\<^sup>*}" + using trancl_insert[of a b r] + by (simp add: rtrancl_trancl_reflcl del: reflcl_trancl) blast text \Simplifying nested closures\ -lemma rtrancl_trancl_absorb[simp]: "(R^*)^+ = R^*" -by (simp add: trans_rtrancl) +lemma rtrancl_trancl_absorb[simp]: "(R\<^sup>*)\<^sup>+ = R\<^sup>*" + by (simp add: trans_rtrancl) -lemma trancl_rtrancl_absorb[simp]: "(R^+)^* = R^*" -by (subst reflcl_trancl[symmetric]) simp +lemma trancl_rtrancl_absorb[simp]: "(R\<^sup>+)\<^sup>* = R\<^sup>*" + by (subst reflcl_trancl[symmetric]) simp -lemma rtrancl_reflcl_absorb[simp]: "(R^*)^= = R^*" -by auto +lemma rtrancl_reflcl_absorb[simp]: "(R\<^sup>*)\<^sup>= = R\<^sup>*" + by auto text \\Domain\ and \Range\\ -lemma Domain_rtrancl [simp]: "Domain (R^*) = UNIV" +lemma Domain_rtrancl [simp]: "Domain (R\<^sup>*) = UNIV" by blast -lemma Range_rtrancl [simp]: "Range (R^*) = UNIV" +lemma Range_rtrancl [simp]: "Range (R\<^sup>*) = UNIV" by blast -lemma rtrancl_Un_subset: "(R^* \ S^*) \ (R Un S)^*" +lemma rtrancl_Un_subset: "(R\<^sup>* \ S\<^sup>*) \ (R \ S)\<^sup>*" by (rule rtrancl_Un_rtrancl [THEN subst]) fast -lemma in_rtrancl_UnI: "x \ R^* \ x \ S^* ==> x \ (R \ S)^*" +lemma in_rtrancl_UnI: "x \ R\<^sup>* \ x \ S\<^sup>* \ x \ (R \ S)\<^sup>*" by (blast intro: subsetD [OF rtrancl_Un_subset]) -lemma trancl_domain [simp]: "Domain (r^+) = Domain r" +lemma trancl_domain [simp]: "Domain (r\<^sup>+) = Domain r" by (unfold Domain_unfold) (blast dest: tranclD) -lemma trancl_range [simp]: "Range (r^+) = Range r" +lemma trancl_range [simp]: "Range (r\<^sup>+) = Range r" unfolding Domain_converse [symmetric] by (simp add: trancl_converse [symmetric]) -lemma Not_Domain_rtrancl: - "x ~: Domain R ==> ((x, y) : R^*) = (x = y)" +lemma Not_Domain_rtrancl: "x \ Domain R \ (x, y) \ R\<^sup>* \ x = y" apply auto apply (erule rev_mp) apply (erule rtrancl_induct) apply auto done -lemma trancl_subset_Field2: "r^+ <= Field r \ Field r" +lemma trancl_subset_Field2: "r\<^sup>+ \ Field r \ Field r" apply clarify apply (erule trancl_induct) apply (auto simp add: Field_def) done -lemma finite_trancl[simp]: "finite (r^+) = finite r" +lemma finite_trancl[simp]: "finite (r\<^sup>+) = finite r" apply auto prefer 2 apply (rule trancl_subset_Field2 [THEN finite_subset]) @@ -672,8 +653,7 @@ be merged with main body.\ lemma single_valued_confluent: - "\ single_valued r; (x,y) \ r^*; (x,z) \ r^* \ - \ (y,z) \ r^* \ (z,y) \ r^*" + "single_valued r \ (x, y) \ r\<^sup>* \ (x, z) \ r\<^sup>* \ (y, z) \ r\<^sup>* \ (z, y) \ r\<^sup>*" apply (erule rtrancl_induct) apply simp apply (erule disjE) @@ -681,18 +661,16 @@ apply(blast intro:rtrancl_trans) done -lemma r_r_into_trancl: "(a, b) \ R ==> (b, c) \ R ==> (a, c) \ R^+" +lemma r_r_into_trancl: "(a, b) \ R \ (b, c) \ R \ (a, c) \ R\<^sup>+" by (fast intro: trancl_trans) -lemma trancl_into_trancl [rule_format]: - "(a, b) \ r\<^sup>+ ==> (b, c) \ r --> (a,c) \ r\<^sup>+" - apply (erule trancl_induct) +lemma trancl_into_trancl: "(a, b) \ r\<^sup>+ \ (b, c) \ r \ (a, c) \ r\<^sup>+" + apply (induct rule: trancl_induct) apply (fast intro: r_r_into_trancl) apply (fast intro: r_r_into_trancl trancl_trans) done -lemma tranclp_rtranclp_tranclp: - "r\<^sup>+\<^sup>+ a b ==> r\<^sup>*\<^sup>* b c ==> r\<^sup>+\<^sup>+ a c" +lemma tranclp_rtranclp_tranclp: "r\<^sup>+\<^sup>+ a b \ r\<^sup>*\<^sup>* b c \ r\<^sup>+\<^sup>+ a c" apply (drule tranclpD) apply (elim exE conjE) apply (drule rtranclp_trans, assumption) @@ -715,37 +693,39 @@ declare trancl_into_rtrancl [elim] + subsection \The power operation on relations\ -text \\R ^^ n = R O ... O R\, the n-fold composition of \R\\ +text \\R ^^ n = R O \ O R\, the n-fold composition of \R\\ overloading - relpow == "compow :: nat \ ('a \ 'a) set \ ('a \ 'a) set" - relpowp == "compow :: nat \ ('a \ 'a \ bool) \ ('a \ 'a \ bool)" + relpow \ "compow :: nat \ ('a \ 'a) set \ ('a \ 'a) set" + relpowp \ "compow :: nat \ ('a \ 'a \ bool) \ ('a \ 'a \ bool)" begin -primrec relpow :: "nat \ ('a \ 'a) set \ ('a \ 'a) set" where - "relpow 0 R = Id" - | "relpow (Suc n) R = (R ^^ n) O R" +primrec relpow :: "nat \ ('a \ 'a) set \ ('a \ 'a) set" +where + "relpow 0 R = Id" +| "relpow (Suc n) R = (R ^^ n) O R" -primrec relpowp :: "nat \ ('a \ 'a \ bool) \ ('a \ 'a \ bool)" where - "relpowp 0 R = HOL.eq" - | "relpowp (Suc n) R = (R ^^ n) OO R" +primrec relpowp :: "nat \ ('a \ 'a \ bool) \ ('a \ 'a \ bool)" +where + "relpowp 0 R = HOL.eq" +| "relpowp (Suc n) R = (R ^^ n) OO R" end lemma relpowp_relpow_eq [pred_set_conv]: - fixes R :: "'a rel" - shows "(\x y. (x, y) \ R) ^^ n = (\x y. (x, y) \ R ^^ n)" + "(\x y. (x, y) \ R) ^^ n = (\x y. (x, y) \ R ^^ n)" for R :: "'a rel" by (induct n) (simp_all add: relcompp_relcomp_eq) -text \for code generation\ +text \For code generation:\ -definition relpow :: "nat \ ('a \ 'a) set \ ('a \ 'a) set" where - relpow_code_def [code_abbrev]: "relpow = compow" +definition relpow :: "nat \ ('a \ 'a) set \ ('a \ 'a) set" + where relpow_code_def [code_abbrev]: "relpow = compow" -definition relpowp :: "nat \ ('a \ 'a \ bool) \ ('a \ 'a \ bool)" where - relpowp_code_def [code_abbrev]: "relpowp = compow" +definition relpowp :: "nat \ ('a \ 'a \ bool) \ ('a \ 'a \ bool)" + where relpowp_code_def [code_abbrev]: "relpowp = compow" lemma [code]: "relpow (Suc n) R = (relpow n R) O R" @@ -760,54 +740,40 @@ hide_const (open) relpow hide_const (open) relpowp -lemma relpow_1 [simp]: - fixes R :: "('a \ 'a) set" - shows "R ^^ 1 = R" +lemma relpow_1 [simp]: "R ^^ 1 = R" for R :: "('a \ 'a) set" by simp -lemma relpowp_1 [simp]: - fixes P :: "'a \ 'a \ bool" - shows "P ^^ 1 = P" +lemma relpowp_1 [simp]: "P ^^ 1 = P" for P :: "'a \ 'a \ bool" by (fact relpow_1 [to_pred]) -lemma relpow_0_I: - "(x, x) \ R ^^ 0" +lemma relpow_0_I: "(x, x) \ R ^^ 0" by simp -lemma relpowp_0_I: - "(P ^^ 0) x x" +lemma relpowp_0_I: "(P ^^ 0) x x" by (fact relpow_0_I [to_pred]) -lemma relpow_Suc_I: - "(x, y) \ R ^^ n \ (y, z) \ R \ (x, z) \ R ^^ Suc n" +lemma relpow_Suc_I: "(x, y) \ R ^^ n \ (y, z) \ R \ (x, z) \ R ^^ Suc n" by auto -lemma relpowp_Suc_I: - "(P ^^ n) x y \ P y z \ (P ^^ Suc n) x z" +lemma relpowp_Suc_I: "(P ^^ n) x y \ P y z \ (P ^^ Suc n) x z" by (fact relpow_Suc_I [to_pred]) -lemma relpow_Suc_I2: - "(x, y) \ R \ (y, z) \ R ^^ n \ (x, z) \ R ^^ Suc n" +lemma relpow_Suc_I2: "(x, y) \ R \ (y, z) \ R ^^ n \ (x, z) \ R ^^ Suc n" by (induct n arbitrary: z) (simp, fastforce) -lemma relpowp_Suc_I2: - "P x y \ (P ^^ n) y z \ (P ^^ Suc n) x z" +lemma relpowp_Suc_I2: "P x y \ (P ^^ n) y z \ (P ^^ Suc n) x z" by (fact relpow_Suc_I2 [to_pred]) -lemma relpow_0_E: - "(x, y) \ R ^^ 0 \ (x = y \ P) \ P" +lemma relpow_0_E: "(x, y) \ R ^^ 0 \ (x = y \ P) \ P" by simp -lemma relpowp_0_E: - "(P ^^ 0) x y \ (x = y \ Q) \ Q" +lemma relpowp_0_E: "(P ^^ 0) x y \ (x = y \ Q) \ Q" by (fact relpow_0_E [to_pred]) -lemma relpow_Suc_E: - "(x, z) \ R ^^ Suc n \ (\y. (x, y) \ R ^^ n \ (y, z) \ R \ P) \ P" +lemma relpow_Suc_E: "(x, z) \ R ^^ Suc n \ (\y. (x, y) \ R ^^ n \ (y, z) \ R \ P) \ P" by auto -lemma relpowp_Suc_E: - "(P ^^ Suc n) x z \ (\y. (P ^^ n) x y \ P y z \ Q) \ Q" +lemma relpowp_Suc_E: "(P ^^ Suc n) x z \ (\y. (P ^^ n) x y \ P y z \ Q) \ Q" by (fact relpow_Suc_E [to_pred]) lemma relpow_E: @@ -822,31 +788,25 @@ \ Q" by (fact relpow_E [to_pred]) -lemma relpow_Suc_D2: - "(x, z) \ R ^^ Suc n \ (\y. (x, y) \ R \ (y, z) \ R ^^ n)" +lemma relpow_Suc_D2: "(x, z) \ R ^^ Suc n \ (\y. (x, y) \ R \ (y, z) \ R ^^ n)" apply (induct n arbitrary: x z) apply (blast intro: relpow_0_I elim: relpow_0_E relpow_Suc_E) apply (blast intro: relpow_Suc_I elim: relpow_0_E relpow_Suc_E) done -lemma relpowp_Suc_D2: - "(P ^^ Suc n) x z \ \y. P x y \ (P ^^ n) y z" +lemma relpowp_Suc_D2: "(P ^^ Suc n) x z \ \y. P x y \ (P ^^ n) y z" by (fact relpow_Suc_D2 [to_pred]) -lemma relpow_Suc_E2: - "(x, z) \ R ^^ Suc n \ (\y. (x, y) \ R \ (y, z) \ R ^^ n \ P) \ P" +lemma relpow_Suc_E2: "(x, z) \ R ^^ Suc n \ (\y. (x, y) \ R \ (y, z) \ R ^^ n \ P) \ P" by (blast dest: relpow_Suc_D2) -lemma relpowp_Suc_E2: - "(P ^^ Suc n) x z \ (\y. P x y \ (P ^^ n) y z \ Q) \ Q" +lemma relpowp_Suc_E2: "(P ^^ Suc n) x z \ (\y. P x y \ (P ^^ n) y z \ Q) \ Q" by (fact relpow_Suc_E2 [to_pred]) -lemma relpow_Suc_D2': - "\x y z. (x, y) \ R ^^ n \ (y, z) \ R \ (\w. (x, w) \ R \ (w, z) \ R ^^ n)" +lemma relpow_Suc_D2': "\x y z. (x, y) \ R ^^ n \ (y, z) \ R \ (\w. (x, w) \ R \ (w, z) \ R ^^ n)" by (induct n) (simp_all, blast) -lemma relpowp_Suc_D2': - "\x y z. (P ^^ n) x y \ P y z \ (\w. P x w \ (P ^^ n) w z)" +lemma relpowp_Suc_D2': "\x y z. (P ^^ n) x y \ P y z \ (\w. P x w \ (P ^^ n) w z)" by (fact relpow_Suc_D2' [to_pred]) lemma relpow_E2: @@ -864,83 +824,78 @@ \ Q" by (fact relpow_E2 [to_pred]) -lemma relpow_add: "R ^^ (m+n) = R^^m O R^^n" +lemma relpow_add: "R ^^ (m + n) = R^^m O R^^n" by (induct n) auto lemma relpowp_add: "P ^^ (m + n) = P ^^ m OO P ^^ n" by (fact relpow_add [to_pred]) lemma relpow_commute: "R O R ^^ n = R ^^ n O R" - by (induct n) (simp, simp add: O_assoc [symmetric]) + by (induct n) (simp_all add: O_assoc [symmetric]) lemma relpowp_commute: "P OO P ^^ n = P ^^ n OO P" by (fact relpow_commute [to_pred]) -lemma relpow_empty: - "0 < n \ ({} :: ('a \ 'a) set) ^^ n = {}" +lemma relpow_empty: "0 < n \ ({} :: ('a \ 'a) set) ^^ n = {}" by (cases n) auto -lemma relpowp_bot: - "0 < n \ (\ :: 'a \ 'a \ bool) ^^ n = \" +lemma relpowp_bot: "0 < n \ (\ :: 'a \ 'a \ bool) ^^ n = \" by (fact relpow_empty [to_pred]) lemma rtrancl_imp_UN_relpow: - assumes "p \ R^*" + assumes "p \ R\<^sup>*" shows "p \ (\n. R ^^ n)" proof (cases p) case (Pair x y) - with assms have "(x, y) \ R^*" by simp + with assms have "(x, y) \ R\<^sup>*" by simp then have "(x, y) \ (\n. R ^^ n)" proof induct - case base show ?case by (blast intro: relpow_0_I) + case base + show ?case by (blast intro: relpow_0_I) next - case step then show ?case by (blast intro: relpow_Suc_I) + case step + then show ?case by (blast intro: relpow_Suc_I) qed with Pair show ?thesis by simp qed lemma rtranclp_imp_Sup_relpowp: - assumes "(P^**) x y" + assumes "(P\<^sup>*\<^sup>*) x y" shows "(\n. P ^^ n) x y" using assms and rtrancl_imp_UN_relpow [of "(x, y)", to_pred] by simp lemma relpow_imp_rtrancl: assumes "p \ R ^^ n" - shows "p \ R^*" + shows "p \ R\<^sup>*" proof (cases p) case (Pair x y) with assms have "(x, y) \ R ^^ n" by simp - then have "(x, y) \ R^*" proof (induct n arbitrary: x y) - case 0 then show ?case by simp + then have "(x, y) \ R\<^sup>*" proof (induct n arbitrary: x y) + case 0 + then show ?case by simp next - case Suc then show ?case + case Suc + then show ?case by (blast elim: relpow_Suc_E intro: rtrancl_into_rtrancl) qed with Pair show ?thesis by simp qed -lemma relpowp_imp_rtranclp: - assumes "(P ^^ n) x y" - shows "(P^**) x y" - using assms and relpow_imp_rtrancl [of "(x, y)", to_pred] by simp +lemma relpowp_imp_rtranclp: "(P ^^ n) x y \ (P\<^sup>*\<^sup>*) x y" + using relpow_imp_rtrancl [of "(x, y)", to_pred] by simp -lemma rtrancl_is_UN_relpow: - "R^* = (\n. R ^^ n)" +lemma rtrancl_is_UN_relpow: "R\<^sup>* = (\n. R ^^ n)" by (blast intro: rtrancl_imp_UN_relpow relpow_imp_rtrancl) -lemma rtranclp_is_Sup_relpowp: - "P^** = (\n. P ^^ n)" +lemma rtranclp_is_Sup_relpowp: "P\<^sup>*\<^sup>* = (\n. P ^^ n)" using rtrancl_is_UN_relpow [to_pred, of P] by auto -lemma rtrancl_power: - "p \ R^* \ (\n. p \ R ^^ n)" +lemma rtrancl_power: "p \ R\<^sup>* \ (\n. p \ R ^^ n)" by (simp add: rtrancl_is_UN_relpow) -lemma rtranclp_power: - "(P^**) x y \ (\n. (P ^^ n) x y)" +lemma rtranclp_power: "(P\<^sup>*\<^sup>*) x y \ (\n. (P ^^ n) x y)" by (simp add: rtranclp_is_Sup_relpowp) -lemma trancl_power: - "p \ R^+ \ (\n > 0. p \ R ^^ n)" +lemma trancl_power: "p \ R\<^sup>+ \ (\n > 0. p \ R ^^ n)" apply (cases p) apply simp apply (rule iffI) @@ -956,187 +911,204 @@ apply (drule rtrancl_into_trancl1) apply auto done -lemma tranclp_power: - "(P^++) x y \ (\n > 0. (P ^^ n) x y)" +lemma tranclp_power: "(P\<^sup>+\<^sup>+) x y \ (\n > 0. (P ^^ n) x y)" using trancl_power [to_pred, of P "(x, y)"] by simp -lemma rtrancl_imp_relpow: - "p \ R^* \ \n. p \ R ^^ n" +lemma rtrancl_imp_relpow: "p \ R\<^sup>* \ \n. p \ R ^^ n" by (auto dest: rtrancl_imp_UN_relpow) -lemma rtranclp_imp_relpowp: - "(P^**) x y \ \n. (P ^^ n) x y" +lemma rtranclp_imp_relpowp: "(P\<^sup>*\<^sup>*) x y \ \n. (P ^^ n) x y" by (auto dest: rtranclp_imp_Sup_relpowp) -text\By Sternagel/Thiemann:\ -lemma relpow_fun_conv: - "((a,b) \ R ^^ n) = (\f. f 0 = a \ f n = b \ (\i R))" +text \By Sternagel/Thiemann:\ +lemma relpow_fun_conv: "(a, b) \ R ^^ n \ (\f. f 0 = a \ f n = b \ (\i R))" proof (induct n arbitrary: b) - case 0 show ?case by auto + case 0 + show ?case by auto next case (Suc n) show ?case proof (simp add: relcomp_unfold Suc) - show "(\y. (\f. f 0 = a \ f n = y \ (\i R)) \ (y,b) \ R) - = (\f. f 0 = a \ f(Suc n) = b \ (\i R))" + show "(\y. (\f. f 0 = a \ f n = y \ (\i R)) \ (y,b) \ R) \ + (\f. f 0 = a \ f(Suc n) = b \ (\i R))" (is "?l = ?r") proof assume ?l - then obtain c f where 1: "f 0 = a" "f n = c" "\i. i < n \ (f i, f (Suc i)) \ R" "(c,b) \ R" by auto + then obtain c f + where 1: "f 0 = a" "f n = c" "\i. i < n \ (f i, f (Suc i)) \ R" "(c,b) \ R" + by auto let ?g = "\ m. if m = Suc n then b else f m" - show ?r by (rule exI[of _ ?g], simp add: 1) + show ?r by (rule exI[of _ ?g]) (simp add: 1) next assume ?r - then obtain f where 1: "f 0 = a" "b = f (Suc n)" "\i. i < Suc n \ (f i, f (Suc i)) \ R" by auto + then obtain f where 1: "f 0 = a" "b = f (Suc n)" "\i. i < Suc n \ (f i, f (Suc i)) \ R" + by auto show ?l by (rule exI[of _ "f n"], rule conjI, rule exI[of _ f], insert 1, auto) qed qed qed -lemma relpowp_fun_conv: - "(P ^^ n) x y \ (\f. f 0 = x \ f n = y \ (\i (\f. f 0 = x \ f n = y \ (\i0" -shows "R^^k \ (UN n:{n. 0 ?r") -proof- - { fix a b k - have "(a,b) : R^^(Suc k) \ EX n. 0 {}" by auto - with card_0_eq[OF \finite R\] have "card R >= Suc 0" by auto - thus ?case using 0 by force + fixes R :: "('a \ 'a) set" + assumes "finite R" and "k > 0" + shows "R^^k \ (\n\{n. 0 < n \ n \ card R}. R^^n)" (is "_ \ ?r") +proof - + have "(a, b) \ R^^(Suc k) \ \n. 0 < n \ n \ card R \ (a, b) \ R^^n" for a b k + proof (induct k arbitrary: b) + case 0 + then have "R \ {}" by auto + with card_0_eq[OF \finite R\] have "card R \ Suc 0" by auto + then show ?case using 0 by force + next + case (Suc k) + then obtain a' where "(a, a') \ R^^(Suc k)" and "(a', b) \ R" + by auto + from Suc(1)[OF \(a, a') \ R^^(Suc k)\] obtain n where "n \ card R" and "(a, a') \ R ^^ n" + by auto + have "(a, b) \ R^^(Suc n)" + using \(a, a') \ R^^n\ and \(a', b)\ R\ by auto + from \n \ card R\ consider "n < card R" | "n = card R" by force + then show ?case + proof cases + case 1 + then show ?thesis + using \(a, b) \ R^^(Suc n)\ Suc_leI[OF \n < card R\] by blast next - case (Suc k) - then obtain a' where "(a,a') : R^^(Suc k)" and "(a',b) : R" by auto - from Suc(1)[OF \(a,a') : R^^(Suc k)\] - obtain n where "n \ card R" and "(a,a') \ R ^^ n" by auto - have "(a,b) : R^^(Suc n)" using \(a,a') \ R^^n\ and \(a',b)\ R\ by auto - { assume "n < card R" - hence ?case using \(a,b): R^^(Suc n)\ Suc_leI[OF \n < card R\] by blast - } moreover - { assume "n = card R" - from \(a,b) \ R ^^ (Suc n)\[unfolded relpow_fun_conv] - obtain f where "f 0 = a" and "f(Suc n) = b" - and steps: "\i. i <= n \ (f i, f (Suc i)) \ R" by auto - let ?p = "%i. (f i, f(Suc i))" - let ?N = "{i. i \ n}" - have "?p ` ?N <= R" using steps by auto - from card_mono[OF assms(1) this] - have "card(?p ` ?N) <= card R" . - also have "\ < card ?N" using \n = card R\ by simp - finally have "~ inj_on ?p ?N" by(rule pigeonhole) - then obtain i j where i: "i <= n" and j: "j <= n" and ij: "i \ j" and - pij: "?p i = ?p j" by(auto simp: inj_on_def) - let ?i = "min i j" let ?j = "max i j" - have i: "?i <= n" and j: "?j <= n" and pij: "?p ?i = ?p ?j" - and ij: "?i < ?j" - using i j ij pij unfolding min_def max_def by auto - from i j pij ij obtain i j where i: "i<=n" and j: "j<=n" and ij: "i R ^^ ?n" unfolding relpow_fun_conv - proof (rule exI[of _ ?g], intro conjI impI allI) - show "?g ?n = b" using \f(Suc n) = b\ j ij by auto + case 2 + from \(a, b) \ R ^^ (Suc n)\ [unfolded relpow_fun_conv] + obtain f where "f 0 = a" and "f (Suc n) = b" + and steps: "\i. i \ n \ (f i, f (Suc i)) \ R" by auto + let ?p = "\i. (f i, f(Suc i))" + let ?N = "{i. i \ n}" + have "?p ` ?N \ R" + using steps by auto + from card_mono[OF assms(1) this] have "card (?p ` ?N) \ card R" . + also have "\ < card ?N" + using \n = card R\ by simp + finally have "\ inj_on ?p ?N" + by (rule pigeonhole) + then obtain i j where i: "i \ n" and j: "j \ n" and ij: "i \ j" and pij: "?p i = ?p j" + by (auto simp: inj_on_def) + let ?i = "min i j" + let ?j = "max i j" + have i: "?i \ n" and j: "?j \ n" and pij: "?p ?i = ?p ?j" and ij: "?i < ?j" + using i j ij pij unfolding min_def max_def by auto + from i j pij ij obtain i j where i: "i \ n" and j: "j \ n" and ij: "i < j" + and pij: "?p i = ?p j" + by blast + let ?g = "\l. if l \ i then f l else f (l + (j - i))" + let ?n = "Suc (n - (j - i))" + have abl: "(a, b) \ R ^^ ?n" + unfolding relpow_fun_conv + proof (rule exI[of _ ?g], intro conjI impI allI) + show "?g ?n = b" + using \f(Suc n) = b\ j ij by auto + next + fix k + assume "k < ?n" + show "(?g k, ?g (Suc k)) \ R" + proof (cases "k < i") + case True + with i have "k \ n" + by auto + from steps[OF this] show ?thesis + using True by simp next - fix k assume "k < ?n" - show "(?g k, ?g (Suc k)) \ R" - proof (cases "k < i") + case False + then have "i \ k" by auto + show ?thesis + proof (cases "k = i") case True - with i have "k <= n" by auto - from steps[OF this] show ?thesis using True by simp + then show ?thesis + using ij pij steps[OF i] by simp next case False - hence "i \ k" by auto + with \i \ k\ have "i < k" by auto + then have small: "k + (j - i) \ n" + using \k by arith show ?thesis - proof (cases "k = i") - case True - thus ?thesis using ij pij steps[OF i] by simp - next - case False - with \i \ k\ have "i < k" by auto - hence small: "k + (j - i) <= n" using \k by arith - show ?thesis using steps[OF small] \i by auto - qed + using steps[OF small] \i by auto qed - qed (simp add: \f 0 = a\) - moreover have "?n <= n" using i j ij by arith - ultimately have ?case using \n = card R\ by blast - } - ultimately show ?case using \n \ card R\ by force + qed + qed (simp add: \f 0 = a\) + moreover have "?n \ n" + using i j ij by arith + ultimately show ?thesis + using \n = card R\ by blast qed - } - thus ?thesis using gr0_implies_Suc[OF \k>0\] by auto + qed + then show ?thesis + using gr0_implies_Suc[OF \k > 0\] by auto qed lemma relpow_finite_bounded: -assumes "finite(R :: ('a*'a)set)" -shows "R^^k \ (UN n:{n. n <= card R}. R^^n)" -apply(cases k) - apply force -using relpow_finite_bounded1[OF assms, of k] by auto + fixes R :: "('a \ 'a) set" + assumes "finite R" + shows "R^^k \ (UN n:{n. n \ card R}. R^^n)" + apply (cases k) + apply force + using relpow_finite_bounded1[OF assms, of k] + apply auto + done -lemma rtrancl_finite_eq_relpow: - "finite R \ R^* = (UN n : {n. n <= card R}. R^^n)" -by(fastforce simp: rtrancl_power dest: relpow_finite_bounded) +lemma rtrancl_finite_eq_relpow: "finite R \ R\<^sup>* = (\n\{n. n \ card R}. R^^n)" + by (fastforce simp: rtrancl_power dest: relpow_finite_bounded) -lemma trancl_finite_eq_relpow: - "finite R \ R^+ = (UN n : {n. 0 < n & n <= card R}. R^^n)" -apply(auto simp add: trancl_power) -apply(auto dest: relpow_finite_bounded1) -done +lemma trancl_finite_eq_relpow: "finite R \ R\<^sup>+ = (\n\{n. 0 < n \ n \ card R}. R^^n)" + apply (auto simp: trancl_power) + apply (auto dest: relpow_finite_bounded1) + done lemma finite_relcomp[simp,intro]: -assumes "finite R" and "finite S" -shows "finite(R O S)" + assumes "finite R" and "finite S" + shows "finite (R O S)" proof- have "R O S = (\(x, y)\R. \(u, v)\S. if u = y then {(x, v)} else {})" by (force simp add: split_def image_constant_conv split: if_splits) - then show ?thesis using assms by clarsimp + then show ?thesis + using assms by clarsimp qed -lemma finite_relpow[simp,intro]: - assumes "finite(R :: ('a*'a)set)" shows "n>0 \ finite(R^^n)" -apply(induct n) - apply simp -apply(case_tac n) - apply(simp_all add: assms) -done +lemma finite_relpow [simp, intro]: + fixes R :: "('a \ 'a) set" + assumes "finite R" + shows "n > 0 \ finite (R^^n)" + apply (induct n) + apply simp + apply (case_tac n) + apply (simp_all add: assms) + done lemma single_valued_relpow: - fixes R :: "('a * 'a) set" + fixes R :: "('a \ 'a) set" shows "single_valued R \ single_valued (R ^^ n)" -apply (induct n arbitrary: R) -apply simp_all -apply (rule single_valuedI) -apply (fast dest: single_valuedD elim: relpow_Suc_E) -done + apply (induct n arbitrary: R) + apply simp_all + apply (rule single_valuedI) + apply (fast dest: single_valuedD elim: relpow_Suc_E) + done subsection \Bounded transitive closure\ definition ntrancl :: "nat \ ('a \ 'a) set \ ('a \ 'a) set" -where - "ntrancl n R = (\i\{i. 0 < i \ i \ Suc n}. R ^^ i)" + where "ntrancl n R = (\i\{i. 0 < i \ i \ Suc n}. R ^^ i)" -lemma ntrancl_Zero [simp, code]: - "ntrancl 0 R = R" +lemma ntrancl_Zero [simp, code]: "ntrancl 0 R = R" proof show "R \ ntrancl 0 R" unfolding ntrancl_def by fastforce next - { - fix i have "0 < i \ i \ Suc 0 \ i = 1" by auto - } - from this show "ntrancl 0 R \ R" + have "0 < i \ i \ Suc 0 \ i = 1" for i + by auto + then show "ntrancl 0 R \ R" unfolding ntrancl_def by auto qed -lemma ntrancl_Suc [simp]: - "ntrancl (Suc n) R = ntrancl n R O (Id \ R)" +lemma ntrancl_Suc [simp]: "ntrancl (Suc n) R = ntrancl n R O (Id \ R)" proof { fix a b @@ -1159,75 +1131,67 @@ from this c2 show ?thesis by fastforce qed } - from this show "ntrancl (Suc n) R \ ntrancl n R O (Id \ R)" + then show "ntrancl (Suc n) R \ ntrancl n R O (Id \ R)" by auto -next show "ntrancl n R O (Id \ R) \ ntrancl (Suc n) R" unfolding ntrancl_def by fastforce qed -lemma [code]: - "ntrancl (Suc n) r = (let r' = ntrancl n r in r' Un r' O r)" -unfolding Let_def by auto +lemma [code]: "ntrancl (Suc n) r = (let r' = ntrancl n r in r' \ r' O r)" + by (auto simp: Let_def) -lemma finite_trancl_ntranl: - "finite R \ trancl R = ntrancl (card R - 1) R" +lemma finite_trancl_ntranl: "finite R \ trancl R = ntrancl (card R - 1) R" by (cases "card R") (auto simp add: trancl_finite_eq_relpow relpow_empty ntrancl_def) subsection \Acyclic relations\ -definition acyclic :: "('a * 'a) set => bool" where - "acyclic r \ (!x. (x,x) ~: r^+)" +definition acyclic :: "('a \ 'a) set \ bool" + where "acyclic r \ (\x. (x,x) \ r\<^sup>+)" -abbreviation acyclicP :: "('a => 'a => bool) => bool" where - "acyclicP r \ acyclic {(x, y). r x y}" +abbreviation acyclicP :: "('a \ 'a \ bool) \ bool" + where "acyclicP r \ acyclic {(x, y). r x y}" -lemma acyclic_irrefl [code]: - "acyclic r \ irrefl (r^+)" +lemma acyclic_irrefl [code]: "acyclic r \ irrefl (r\<^sup>+)" by (simp add: acyclic_def irrefl_def) -lemma acyclicI: "ALL x. (x, x) ~: r^+ ==> acyclic r" +lemma acyclicI: "\x. (x, x) \ r\<^sup>+ \ acyclic r" by (simp add: acyclic_def) lemma (in order) acyclicI_order: assumes *: "\a b. (a, b) \ r \ f b < f a" shows "acyclic r" proof - - { fix a b assume "(a, b) \ r\<^sup>+" - then have "f b < f a" - by induct (auto intro: * less_trans) } + have "f b < f a" if "(a, b) \ r\<^sup>+" for a b + using that by induct (auto intro: * less_trans) then show ?thesis by (auto intro!: acyclicI) qed -lemma acyclic_insert [iff]: - "acyclic(insert (y,x) r) = (acyclic r & (x,y) ~: r^*)" -apply (simp add: acyclic_def trancl_insert) -apply (blast intro: rtrancl_trans) -done +lemma acyclic_insert [iff]: "acyclic (insert (y, x) r) \ acyclic r \ (x, y) \ r\<^sup>*" + apply (simp add: acyclic_def trancl_insert) + apply (blast intro: rtrancl_trans) + done -lemma acyclic_converse [iff]: "acyclic(r^-1) = acyclic r" -by (simp add: acyclic_def trancl_converse) +lemma acyclic_converse [iff]: "acyclic (r\) \ acyclic r" + by (simp add: acyclic_def trancl_converse) lemmas acyclicP_converse [iff] = acyclic_converse [to_pred] -lemma acyclic_impl_antisym_rtrancl: "acyclic r ==> antisym(r^*)" -apply (simp add: acyclic_def antisym_def) -apply (blast elim: rtranclE intro: rtrancl_into_trancl1 rtrancl_trancl_trancl) -done +lemma acyclic_impl_antisym_rtrancl: "acyclic r \ antisym (r\<^sup>*)" + apply (simp add: acyclic_def antisym_def) + apply (blast elim: rtranclE intro: rtrancl_into_trancl1 rtrancl_trancl_trancl) + done (* Other direction: acyclic = no loops antisym = only self loops -Goalw [acyclic_def,antisym_def] "antisym( r^* ) ==> acyclic(r - Id) -==> antisym( r^* ) = acyclic(r - Id)"; +Goalw [acyclic_def,antisym_def] "antisym( r\<^sup>* ) \ acyclic(r - Id) +\ antisym( r\<^sup>* ) = acyclic(r - Id)"; *) -lemma acyclic_subset: "[| acyclic s; r <= s |] ==> acyclic r" -apply (simp add: acyclic_def) -apply (blast intro: trancl_mono) -done +lemma acyclic_subset: "acyclic s \ r \ s \ acyclic r" + unfolding acyclic_def by (blast intro: trancl_mono) subsection \Setup of transitivity reasoner\ @@ -1246,14 +1210,16 @@ val rtrancl_trans = @{thm rtrancl_trans}; fun decomp (@{const Trueprop} $ t) = - let fun dec (Const (@{const_name Set.member}, _) $ (Const (@{const_name Pair}, _) $ a $ b) $ rel ) = - let fun decr (Const (@{const_name rtrancl}, _ ) $ r) = (r,"r*") - | decr (Const (@{const_name trancl}, _ ) $ r) = (r,"r+") - | decr r = (r,"r"); - val (rel,r) = decr (Envir.beta_eta_contract rel); - in SOME (a,b,rel,r) end - | dec _ = NONE - in dec t end + let + fun dec (Const (@{const_name Set.member}, _) $ (Const (@{const_name Pair}, _) $ a $ b) $ rel) = + let + fun decr (Const (@{const_name rtrancl}, _ ) $ r) = (r,"r*") + | decr (Const (@{const_name trancl}, _ ) $ r) = (r,"r+") + | decr r = (r,"r"); + val (rel,r) = decr (Envir.beta_eta_contract rel); + in SOME (a,b,rel,r) end + | dec _ = NONE + in dec t end | decomp _ = NONE; ); @@ -1269,14 +1235,16 @@ val rtrancl_trans = @{thm rtranclp_trans}; fun decomp (@{const Trueprop} $ t) = - let fun dec (rel $ a $ b) = - let fun decr (Const (@{const_name rtranclp}, _ ) $ r) = (r,"r*") - | decr (Const (@{const_name tranclp}, _ ) $ r) = (r,"r+") - | decr r = (r,"r"); - val (rel,r) = decr rel; - in SOME (a, b, rel, r) end - | dec _ = NONE - in dec t end + let + fun dec (rel $ a $ b) = + let + fun decr (Const (@{const_name rtranclp}, _ ) $ r) = (r,"r*") + | decr (Const (@{const_name tranclp}, _ ) $ r) = (r,"r+") + | decr r = (r,"r"); + val (rel,r) = decr rel; + in SOME (a, b, rel, r) end + | dec _ = NONE + in dec t end | decomp _ = NONE; ); \