diff --git a/src/HOL/Lattices.thy b/src/HOL/Lattices.thy --- a/src/HOL/Lattices.thy +++ b/src/HOL/Lattices.thy @@ -1,969 +1,969 @@ (* Title: HOL/Lattices.thy Author: Tobias Nipkow *) section \Abstract lattices\ theory Lattices imports Groups begin subsection \Abstract semilattice\ text \ These locales provide a basic structure for interpretation into bigger structures; extensions require careful thinking, otherwise undesired effects may occur due to interpretation. \ locale semilattice = abel_semigroup + assumes idem [simp]: "a \<^bold>* a = a" begin lemma left_idem [simp]: "a \<^bold>* (a \<^bold>* b) = a \<^bold>* b" by (simp add: assoc [symmetric]) lemma right_idem [simp]: "(a \<^bold>* b) \<^bold>* b = a \<^bold>* b" by (simp add: assoc) end locale semilattice_neutr = semilattice + comm_monoid locale semilattice_order = semilattice + fixes less_eq :: "'a \ 'a \ bool" (infix "\<^bold>\" 50) and less :: "'a \ 'a \ bool" (infix "\<^bold><" 50) assumes order_iff: "a \<^bold>\ b \ a = a \<^bold>* b" and strict_order_iff: "a \<^bold>< b \ a = a \<^bold>* b \ a \ b" begin lemma orderI: "a = a \<^bold>* b \ a \<^bold>\ b" by (simp add: order_iff) lemma orderE: assumes "a \<^bold>\ b" obtains "a = a \<^bold>* b" using assms by (unfold order_iff) sublocale ordering less_eq less proof show "a \<^bold>< b \ a \<^bold>\ b \ a \ b" for a b by (simp add: order_iff strict_order_iff) next show "a \<^bold>\ a" for a by (simp add: order_iff) next fix a b assume "a \<^bold>\ b" "b \<^bold>\ a" then have "a = a \<^bold>* b" "a \<^bold>* b = b" by (simp_all add: order_iff commute) then show "a = b" by simp next fix a b c assume "a \<^bold>\ b" "b \<^bold>\ c" then have "a = a \<^bold>* b" "b = b \<^bold>* c" by (simp_all add: order_iff commute) then have "a = a \<^bold>* (b \<^bold>* c)" by simp then have "a = (a \<^bold>* b) \<^bold>* c" by (simp add: assoc) with \a = a \<^bold>* b\ [symmetric] have "a = a \<^bold>* c" by simp then show "a \<^bold>\ c" by (rule orderI) qed lemma cobounded1 [simp]: "a \<^bold>* b \<^bold>\ a" by (simp add: order_iff commute) lemma cobounded2 [simp]: "a \<^bold>* b \<^bold>\ b" by (simp add: order_iff) lemma boundedI: assumes "a \<^bold>\ b" and "a \<^bold>\ c" shows "a \<^bold>\ b \<^bold>* c" proof (rule orderI) from assms obtain "a \<^bold>* b = a" and "a \<^bold>* c = a" by (auto elim!: orderE) then show "a = a \<^bold>* (b \<^bold>* c)" by (simp add: assoc [symmetric]) qed lemma boundedE: assumes "a \<^bold>\ b \<^bold>* c" obtains "a \<^bold>\ b" and "a \<^bold>\ c" using assms by (blast intro: trans cobounded1 cobounded2) lemma bounded_iff [simp]: "a \<^bold>\ b \<^bold>* c \ a \<^bold>\ b \ a \<^bold>\ c" by (blast intro: boundedI elim: boundedE) lemma strict_boundedE: assumes "a \<^bold>< b \<^bold>* c" obtains "a \<^bold>< b" and "a \<^bold>< c" using assms by (auto simp add: commute strict_iff_order elim: orderE intro!: that)+ lemma coboundedI1: "a \<^bold>\ c \ a \<^bold>* b \<^bold>\ c" by (rule trans) auto lemma coboundedI2: "b \<^bold>\ c \ a \<^bold>* b \<^bold>\ c" by (rule trans) auto lemma strict_coboundedI1: "a \<^bold>< c \ a \<^bold>* b \<^bold>< c" using irrefl by (auto intro: not_eq_order_implies_strict coboundedI1 strict_implies_order elim: strict_boundedE) lemma strict_coboundedI2: "b \<^bold>< c \ a \<^bold>* b \<^bold>< c" using strict_coboundedI1 [of b c a] by (simp add: commute) lemma mono: "a \<^bold>\ c \ b \<^bold>\ d \ a \<^bold>* b \<^bold>\ c \<^bold>* d" by (blast intro: boundedI coboundedI1 coboundedI2) lemma absorb1: "a \<^bold>\ b \ a \<^bold>* b = a" by (rule antisym) (auto simp: refl) lemma absorb2: "b \<^bold>\ a \ a \<^bold>* b = b" by (rule antisym) (auto simp: refl) lemma absorb_iff1: "a \<^bold>\ b \ a \<^bold>* b = a" using order_iff by auto lemma absorb_iff2: "b \<^bold>\ a \ a \<^bold>* b = b" using order_iff by (auto simp add: commute) end locale semilattice_neutr_order = semilattice_neutr + semilattice_order begin sublocale ordering_top less_eq less "\<^bold>1" by standard (simp add: order_iff) end text \Passive interpretations for boolean operators\ lemma semilattice_neutr_and: "semilattice_neutr HOL.conj True" by standard auto lemma semilattice_neutr_or: "semilattice_neutr HOL.disj False" by standard auto subsection \Syntactic infimum and supremum operations\ class inf = fixes inf :: "'a \ 'a \ 'a" (infixl "\" 70) class sup = fixes sup :: "'a \ 'a \ 'a" (infixl "\" 65) subsection \Concrete lattices\ -class semilattice_inf = order + inf + +class semilattice_inf = order + inf + assumes inf_le1 [simp]: "x \ y \ x" and inf_le2 [simp]: "x \ y \ y" and inf_greatest: "x \ y \ x \ z \ x \ y \ z" class semilattice_sup = order + sup + assumes sup_ge1 [simp]: "x \ x \ y" and sup_ge2 [simp]: "y \ x \ y" and sup_least: "y \ x \ z \ x \ y \ z \ x" begin text \Dual lattice.\ lemma dual_semilattice: "class.semilattice_inf sup greater_eq greater" by (rule class.semilattice_inf.intro, rule dual_order) (unfold_locales, simp_all add: sup_least) end class lattice = semilattice_inf + semilattice_sup subsubsection \Intro and elim rules\ context semilattice_inf begin lemma le_infI1: "a \ x \ a \ b \ x" by (rule order_trans) auto lemma le_infI2: "b \ x \ a \ b \ x" by (rule order_trans) auto lemma le_infI: "x \ a \ x \ b \ x \ a \ b" by (fact inf_greatest) (* FIXME: duplicate lemma *) lemma le_infE: "x \ a \ b \ (x \ a \ x \ b \ P) \ P" by (blast intro: order_trans inf_le1 inf_le2) lemma le_inf_iff: "x \ y \ z \ x \ y \ x \ z" by (blast intro: le_infI elim: le_infE) lemma le_iff_inf: "x \ y \ x \ y = x" by (auto intro: le_infI1 antisym dest: eq_iff [THEN iffD1] simp add: le_inf_iff) lemma inf_mono: "a \ c \ b \ d \ a \ b \ c \ d" by (fast intro: inf_greatest le_infI1 le_infI2) lemma mono_inf: "mono f \ f (A \ B) \ f A \ f B" for f :: "'a \ 'b::semilattice_inf" by (auto simp add: mono_def intro: Lattices.inf_greatest) end context semilattice_sup begin lemma le_supI1: "x \ a \ x \ a \ b" by (rule order_trans) auto lemma le_supI2: "x \ b \ x \ a \ b" by (rule order_trans) auto lemma le_supI: "a \ x \ b \ x \ a \ b \ x" by (fact sup_least) (* FIXME: duplicate lemma *) lemma le_supE: "a \ b \ x \ (a \ x \ b \ x \ P) \ P" by (blast intro: order_trans sup_ge1 sup_ge2) lemma le_sup_iff: "x \ y \ z \ x \ z \ y \ z" by (blast intro: le_supI elim: le_supE) lemma le_iff_sup: "x \ y \ x \ y = y" by (auto intro: le_supI2 antisym dest: eq_iff [THEN iffD1] simp add: le_sup_iff) lemma sup_mono: "a \ c \ b \ d \ a \ b \ c \ d" by (fast intro: sup_least le_supI1 le_supI2) lemma mono_sup: "mono f \ f A \ f B \ f (A \ B)" for f :: "'a \ 'b::semilattice_sup" by (auto simp add: mono_def intro: Lattices.sup_least) end subsubsection \Equational laws\ context semilattice_inf begin sublocale inf: semilattice inf proof fix a b c show "(a \ b) \ c = a \ (b \ c)" by (rule antisym) (auto intro: le_infI1 le_infI2 simp add: le_inf_iff) show "a \ b = b \ a" by (rule antisym) (auto simp add: le_inf_iff) show "a \ a = a" by (rule antisym) (auto simp add: le_inf_iff) qed sublocale inf: semilattice_order inf less_eq less by standard (auto simp add: le_iff_inf less_le) lemma inf_assoc: "(x \ y) \ z = x \ (y \ z)" by (fact inf.assoc) lemma inf_commute: "(x \ y) = (y \ x)" by (fact inf.commute) lemma inf_left_commute: "x \ (y \ z) = y \ (x \ z)" by (fact inf.left_commute) lemma inf_idem: "x \ x = x" by (fact inf.idem) (* already simp *) lemma inf_left_idem: "x \ (x \ y) = x \ y" by (fact inf.left_idem) (* already simp *) lemma inf_right_idem: "(x \ y) \ y = x \ y" by (fact inf.right_idem) (* already simp *) lemma inf_absorb1: "x \ y \ x \ y = x" by (rule antisym) auto lemma inf_absorb2: "y \ x \ x \ y = y" by (rule antisym) auto lemmas inf_aci = inf_commute inf_assoc inf_left_commute inf_left_idem end context semilattice_sup begin sublocale sup: semilattice sup proof fix a b c show "(a \ b) \ c = a \ (b \ c)" by (rule antisym) (auto intro: le_supI1 le_supI2 simp add: le_sup_iff) show "a \ b = b \ a" by (rule antisym) (auto simp add: le_sup_iff) show "a \ a = a" by (rule antisym) (auto simp add: le_sup_iff) qed sublocale sup: semilattice_order sup greater_eq greater by standard (auto simp add: le_iff_sup sup.commute less_le) lemma sup_assoc: "(x \ y) \ z = x \ (y \ z)" by (fact sup.assoc) lemma sup_commute: "(x \ y) = (y \ x)" by (fact sup.commute) lemma sup_left_commute: "x \ (y \ z) = y \ (x \ z)" by (fact sup.left_commute) lemma sup_idem: "x \ x = x" by (fact sup.idem) (* already simp *) lemma sup_left_idem [simp]: "x \ (x \ y) = x \ y" by (fact sup.left_idem) lemma sup_absorb1: "y \ x \ x \ y = x" by (rule antisym) auto lemma sup_absorb2: "x \ y \ x \ y = y" by (rule antisym) auto lemmas sup_aci = sup_commute sup_assoc sup_left_commute sup_left_idem end context lattice begin lemma dual_lattice: "class.lattice sup (\) (>) inf" by (rule class.lattice.intro, rule dual_semilattice, rule class.semilattice_sup.intro, rule dual_order) (unfold_locales, auto) lemma inf_sup_absorb [simp]: "x \ (x \ y) = x" by (blast intro: antisym inf_le1 inf_greatest sup_ge1) lemma sup_inf_absorb [simp]: "x \ (x \ y) = x" by (blast intro: antisym sup_ge1 sup_least inf_le1) lemmas inf_sup_aci = inf_aci sup_aci lemmas inf_sup_ord = inf_le1 inf_le2 sup_ge1 sup_ge2 text \Towards distributivity.\ lemma distrib_sup_le: "x \ (y \ z) \ (x \ y) \ (x \ z)" by (auto intro: le_infI1 le_infI2 le_supI1 le_supI2) lemma distrib_inf_le: "(x \ y) \ (x \ z) \ x \ (y \ z)" by (auto intro: le_infI1 le_infI2 le_supI1 le_supI2) text \If you have one of them, you have them all.\ lemma distrib_imp1: assumes distrib: "\x y z. x \ (y \ z) = (x \ y) \ (x \ z)" shows "x \ (y \ z) = (x \ y) \ (x \ z)" proof- have "x \ (y \ z) = (x \ (x \ z)) \ (y \ z)" by simp also have "\ = x \ (z \ (x \ y))" by (simp add: distrib inf_commute sup_assoc del: sup_inf_absorb) also have "\ = ((x \ y) \ x) \ ((x \ y) \ z)" by (simp add: inf_commute) also have "\ = (x \ y) \ (x \ z)" by(simp add:distrib) finally show ?thesis . qed lemma distrib_imp2: assumes distrib: "\x y z. x \ (y \ z) = (x \ y) \ (x \ z)" shows "x \ (y \ z) = (x \ y) \ (x \ z)" proof- have "x \ (y \ z) = (x \ (x \ z)) \ (y \ z)" by simp also have "\ = x \ (z \ (x \ y))" by (simp add: distrib sup_commute inf_assoc del: inf_sup_absorb) also have "\ = ((x \ y) \ x) \ ((x \ y) \ z)" by (simp add: sup_commute) also have "\ = (x \ y) \ (x \ z)" by (simp add:distrib) finally show ?thesis . qed end subsubsection \Strict order\ context semilattice_inf begin lemma less_infI1: "a < x \ a \ b < x" by (auto simp add: less_le inf_absorb1 intro: le_infI1) lemma less_infI2: "b < x \ a \ b < x" by (auto simp add: less_le inf_absorb2 intro: le_infI2) end context semilattice_sup begin lemma less_supI1: "x < a \ x < a \ b" using dual_semilattice by (rule semilattice_inf.less_infI1) lemma less_supI2: "x < b \ x < a \ b" using dual_semilattice by (rule semilattice_inf.less_infI2) end subsection \Distributive lattices\ class distrib_lattice = lattice + assumes sup_inf_distrib1: "x \ (y \ z) = (x \ y) \ (x \ z)" context distrib_lattice begin lemma sup_inf_distrib2: "(y \ z) \ x = (y \ x) \ (z \ x)" by (simp add: sup_commute sup_inf_distrib1) lemma inf_sup_distrib1: "x \ (y \ z) = (x \ y) \ (x \ z)" by (rule distrib_imp2 [OF sup_inf_distrib1]) lemma inf_sup_distrib2: "(y \ z) \ x = (y \ x) \ (z \ x)" by (simp add: inf_commute inf_sup_distrib1) lemma dual_distrib_lattice: "class.distrib_lattice sup (\) (>) inf" by (rule class.distrib_lattice.intro, rule dual_lattice) (unfold_locales, fact inf_sup_distrib1) lemmas sup_inf_distrib = sup_inf_distrib1 sup_inf_distrib2 lemmas inf_sup_distrib = inf_sup_distrib1 inf_sup_distrib2 lemmas distrib = sup_inf_distrib1 sup_inf_distrib2 inf_sup_distrib1 inf_sup_distrib2 end subsection \Bounded lattices and boolean algebras\ class bounded_semilattice_inf_top = semilattice_inf + order_top begin sublocale inf_top: semilattice_neutr inf top + inf_top: semilattice_neutr_order inf top less_eq less proof show "x \ \ = x" for x by (rule inf_absorb1) simp qed end class bounded_semilattice_sup_bot = semilattice_sup + order_bot begin sublocale sup_bot: semilattice_neutr sup bot + sup_bot: semilattice_neutr_order sup bot greater_eq greater proof show "x \ \ = x" for x by (rule sup_absorb1) simp qed end class bounded_lattice_bot = lattice + order_bot begin subclass bounded_semilattice_sup_bot .. lemma inf_bot_left [simp]: "\ \ x = \" by (rule inf_absorb1) simp lemma inf_bot_right [simp]: "x \ \ = \" by (rule inf_absorb2) simp lemma sup_bot_left: "\ \ x = x" by (fact sup_bot.left_neutral) lemma sup_bot_right: "x \ \ = x" by (fact sup_bot.right_neutral) lemma sup_eq_bot_iff [simp]: "x \ y = \ \ x = \ \ y = \" by (simp add: eq_iff) lemma bot_eq_sup_iff [simp]: "\ = x \ y \ x = \ \ y = \" by (simp add: eq_iff) end class bounded_lattice_top = lattice + order_top begin subclass bounded_semilattice_inf_top .. lemma sup_top_left [simp]: "\ \ x = \" by (rule sup_absorb1) simp lemma sup_top_right [simp]: "x \ \ = \" by (rule sup_absorb2) simp lemma inf_top_left: "\ \ x = x" by (fact inf_top.left_neutral) lemma inf_top_right: "x \ \ = x" by (fact inf_top.right_neutral) lemma inf_eq_top_iff [simp]: "x \ y = \ \ x = \ \ y = \" by (simp add: eq_iff) end class bounded_lattice = lattice + order_bot + order_top begin subclass bounded_lattice_bot .. subclass bounded_lattice_top .. lemma dual_bounded_lattice: "class.bounded_lattice sup greater_eq greater inf \ \" by unfold_locales (auto simp add: less_le_not_le) end class boolean_algebra = distrib_lattice + bounded_lattice + minus + uminus + assumes inf_compl_bot: "x \ - x = \" and sup_compl_top: "x \ - x = \" assumes diff_eq: "x - y = x \ - y" begin lemma dual_boolean_algebra: "class.boolean_algebra (\x y. x \ - y) uminus sup greater_eq greater inf \ \" by (rule class.boolean_algebra.intro, rule dual_bounded_lattice, rule dual_distrib_lattice) (unfold_locales, auto simp add: inf_compl_bot sup_compl_top diff_eq) lemma compl_inf_bot [simp]: "- x \ x = \" by (simp add: inf_commute inf_compl_bot) lemma compl_sup_top [simp]: "- x \ x = \" by (simp add: sup_commute sup_compl_top) lemma compl_unique: assumes "x \ y = \" and "x \ y = \" shows "- x = y" proof - have "(x \ - x) \ (- x \ y) = (x \ y) \ (- x \ y)" using inf_compl_bot assms(1) by simp then have "(- x \ x) \ (- x \ y) = (y \ x) \ (y \ - x)" by (simp add: inf_commute) then have "- x \ (x \ y) = y \ (x \ - x)" by (simp add: inf_sup_distrib1) then have "- x \ \ = y \ \" using sup_compl_top assms(2) by simp then show "- x = y" by simp qed lemma double_compl [simp]: "- (- x) = x" using compl_inf_bot compl_sup_top by (rule compl_unique) lemma compl_eq_compl_iff [simp]: "- x = - y \ x = y" proof assume "- x = - y" then have "- (- x) = - (- y)" by (rule arg_cong) then show "x = y" by simp next assume "x = y" then show "- x = - y" by simp qed lemma compl_bot_eq [simp]: "- \ = \" proof - from sup_compl_top have "\ \ - \ = \" . then show ?thesis by simp qed lemma compl_top_eq [simp]: "- \ = \" proof - from inf_compl_bot have "\ \ - \ = \" . then show ?thesis by simp qed lemma compl_inf [simp]: "- (x \ y) = - x \ - y" proof (rule compl_unique) have "(x \ y) \ (- x \ - y) = (y \ (x \ - x)) \ (x \ (y \ - y))" by (simp only: inf_sup_distrib inf_aci) then show "(x \ y) \ (- x \ - y) = \" by (simp add: inf_compl_bot) next have "(x \ y) \ (- x \ - y) = (- y \ (x \ - x)) \ (- x \ (y \ - y))" by (simp only: sup_inf_distrib sup_aci) then show "(x \ y) \ (- x \ - y) = \" by (simp add: sup_compl_top) qed lemma compl_sup [simp]: "- (x \ y) = - x \ - y" using dual_boolean_algebra by (rule boolean_algebra.compl_inf) lemma compl_mono: assumes "x \ y" shows "- y \ - x" proof - from assms have "x \ y = y" by (simp only: le_iff_sup) then have "- (x \ y) = - y" by simp then have "- x \ - y = - y" by simp then have "- y \ - x = - y" by (simp only: inf_commute) then show ?thesis by (simp only: le_iff_inf) qed lemma compl_le_compl_iff [simp]: "- x \ - y \ y \ x" by (auto dest: compl_mono) lemma compl_le_swap1: assumes "y \ - x" shows "x \ -y" proof - from assms have "- (- x) \ - y" by (simp only: compl_le_compl_iff) then show ?thesis by simp qed lemma compl_le_swap2: assumes "- y \ x" shows "- x \ y" proof - from assms have "- x \ - (- y)" by (simp only: compl_le_compl_iff) then show ?thesis by simp qed lemma compl_less_compl_iff: "- x < - y \ y < x" (* TODO: declare [simp] ? *) by (auto simp add: less_le) lemma compl_less_swap1: assumes "y < - x" shows "x < - y" proof - from assms have "- (- x) < - y" by (simp only: compl_less_compl_iff) then show ?thesis by simp qed lemma compl_less_swap2: assumes "- y < x" shows "- x < y" proof - from assms have "- x < - (- y)" by (simp only: compl_less_compl_iff) then show ?thesis by simp qed lemma sup_cancel_left1: "sup (sup x a) (sup (- x) b) = top" by (simp add: inf_sup_aci sup_compl_top) lemma sup_cancel_left2: "sup (sup (- x) a) (sup x b) = top" by (simp add: inf_sup_aci sup_compl_top) lemma inf_cancel_left1: "inf (inf x a) (inf (- x) b) = bot" by (simp add: inf_sup_aci inf_compl_bot) lemma inf_cancel_left2: "inf (inf (- x) a) (inf x b) = bot" by (simp add: inf_sup_aci inf_compl_bot) declare inf_compl_bot [simp] and sup_compl_top [simp] lemma sup_compl_top_left1 [simp]: "sup (- x) (sup x y) = top" by (simp add: sup_assoc[symmetric]) lemma sup_compl_top_left2 [simp]: "sup x (sup (- x) y) = top" using sup_compl_top_left1[of "- x" y] by simp lemma inf_compl_bot_left1 [simp]: "inf (- x) (inf x y) = bot" by (simp add: inf_assoc[symmetric]) lemma inf_compl_bot_left2 [simp]: "inf x (inf (- x) y) = bot" using inf_compl_bot_left1[of "- x" y] by simp lemma inf_compl_bot_right [simp]: "inf x (inf y (- x)) = bot" by (subst inf_left_commute) simp end locale boolean_algebra_cancel begin lemma sup1: "(A::'a::semilattice_sup) \ sup k a \ sup A b \ sup k (sup a b)" by (simp only: ac_simps) lemma sup2: "(B::'a::semilattice_sup) \ sup k b \ sup a B \ sup k (sup a b)" by (simp only: ac_simps) lemma sup0: "(a::'a::bounded_semilattice_sup_bot) \ sup a bot" by simp lemma inf1: "(A::'a::semilattice_inf) \ inf k a \ inf A b \ inf k (inf a b)" by (simp only: ac_simps) lemma inf2: "(B::'a::semilattice_inf) \ inf k b \ inf a B \ inf k (inf a b)" by (simp only: ac_simps) lemma inf0: "(a::'a::bounded_semilattice_inf_top) \ inf a top" by simp end ML_file \Tools/boolean_algebra_cancel.ML\ simproc_setup boolean_algebra_cancel_sup ("sup a b::'a::boolean_algebra") = \fn phi => fn ss => try Boolean_Algebra_Cancel.cancel_sup_conv\ simproc_setup boolean_algebra_cancel_inf ("inf a b::'a::boolean_algebra") = \fn phi => fn ss => try Boolean_Algebra_Cancel.cancel_inf_conv\ subsection \\min/max\ as special case of lattice\ context linorder begin sublocale min: semilattice_order min less_eq less + max: semilattice_order max greater_eq greater by standard (auto simp add: min_def max_def) lemma min_le_iff_disj: "min x y \ z \ x \ z \ y \ z" unfolding min_def using linear by (auto intro: order_trans) lemma le_max_iff_disj: "z \ max x y \ z \ x \ z \ y" unfolding max_def using linear by (auto intro: order_trans) lemma min_less_iff_disj: "min x y < z \ x < z \ y < z" unfolding min_def le_less using less_linear by (auto intro: less_trans) lemma less_max_iff_disj: "z < max x y \ z < x \ z < y" unfolding max_def le_less using less_linear by (auto intro: less_trans) lemma min_less_iff_conj [simp]: "z < min x y \ z < x \ z < y" unfolding min_def le_less using less_linear by (auto intro: less_trans) lemma max_less_iff_conj [simp]: "max x y < z \ x < z \ y < z" unfolding max_def le_less using less_linear by (auto intro: less_trans) lemma min_max_distrib1: "min (max b c) a = max (min b a) (min c a)" by (auto simp add: min_def max_def not_le dest: le_less_trans less_trans intro: antisym) lemma min_max_distrib2: "min a (max b c) = max (min a b) (min a c)" by (auto simp add: min_def max_def not_le dest: le_less_trans less_trans intro: antisym) lemma max_min_distrib1: "max (min b c) a = min (max b a) (max c a)" by (auto simp add: min_def max_def not_le dest: le_less_trans less_trans intro: antisym) lemma max_min_distrib2: "max a (min b c) = min (max a b) (max a c)" by (auto simp add: min_def max_def not_le dest: le_less_trans less_trans intro: antisym) lemmas min_max_distribs = min_max_distrib1 min_max_distrib2 max_min_distrib1 max_min_distrib2 lemma split_min [no_atp]: "P (min i j) \ (i \ j \ P i) \ (\ i \ j \ P j)" by (simp add: min_def) lemma split_max [no_atp]: "P (max i j) \ (i \ j \ P j) \ (\ i \ j \ P i)" by (simp add: max_def) lemma min_of_mono: "mono f \ min (f m) (f n) = f (min m n)" for f :: "'a \ 'b::linorder" by (auto simp: mono_def Orderings.min_def min_def intro: Orderings.antisym) lemma max_of_mono: "mono f \ max (f m) (f n) = f (max m n)" for f :: "'a \ 'b::linorder" by (auto simp: mono_def Orderings.max_def max_def intro: Orderings.antisym) end lemma max_of_antimono: "antimono f \ max (f x) (f y) = f (min x y)" and min_of_antimono: "antimono f \ min (f x) (f y) = f (max x y)" for f::"'a::linorder \ 'b::linorder" by (auto simp: antimono_def Orderings.max_def min_def intro!: antisym) lemma inf_min: "inf = (min :: 'a::{semilattice_inf,linorder} \ 'a \ 'a)" by (auto intro: antisym simp add: min_def fun_eq_iff) lemma sup_max: "sup = (max :: 'a::{semilattice_sup,linorder} \ 'a \ 'a)" by (auto intro: antisym simp add: max_def fun_eq_iff) subsection \Uniqueness of inf and sup\ lemma (in semilattice_inf) inf_unique: fixes f (infixl "\" 70) assumes le1: "\x y. x \ y \ x" and le2: "\x y. x \ y \ y" and greatest: "\x y z. x \ y \ x \ z \ x \ y \ z" shows "x \ y = x \ y" proof (rule antisym) show "x \ y \ x \ y" by (rule le_infI) (rule le1, rule le2) have leI: "\x y z. x \ y \ x \ z \ x \ y \ z" by (blast intro: greatest) show "x \ y \ x \ y" by (rule leI) simp_all qed lemma (in semilattice_sup) sup_unique: fixes f (infixl "\" 70) assumes ge1 [simp]: "\x y. x \ x \ y" and ge2: "\x y. y \ x \ y" and least: "\x y z. y \ x \ z \ x \ y \ z \ x" shows "x \ y = x \ y" proof (rule antisym) show "x \ y \ x \ y" by (rule le_supI) (rule ge1, rule ge2) have leI: "\x y z. x \ z \ y \ z \ x \ y \ z" by (blast intro: least) show "x \ y \ x \ y" by (rule leI) simp_all qed subsection \Lattice on \<^typ>\bool\\ instantiation bool :: boolean_algebra begin definition bool_Compl_def [simp]: "uminus = Not" definition bool_diff_def [simp]: "A - B \ A \ \ B" definition [simp]: "P \ Q \ P \ Q" definition [simp]: "P \ Q \ P \ Q" instance by standard auto end lemma sup_boolI1: "P \ P \ Q" by simp lemma sup_boolI2: "Q \ P \ Q" by simp lemma sup_boolE: "P \ Q \ (P \ R) \ (Q \ R) \ R" by auto subsection \Lattice on \<^typ>\_ \ _\\ instantiation "fun" :: (type, semilattice_sup) semilattice_sup begin definition "f \ g = (\x. f x \ g x)" lemma sup_apply [simp, code]: "(f \ g) x = f x \ g x" by (simp add: sup_fun_def) instance by standard (simp_all add: le_fun_def) end instantiation "fun" :: (type, semilattice_inf) semilattice_inf begin definition "f \ g = (\x. f x \ g x)" lemma inf_apply [simp, code]: "(f \ g) x = f x \ g x" by (simp add: inf_fun_def) instance by standard (simp_all add: le_fun_def) end instance "fun" :: (type, lattice) lattice .. instance "fun" :: (type, distrib_lattice) distrib_lattice by standard (rule ext, simp add: sup_inf_distrib1) instance "fun" :: (type, bounded_lattice) bounded_lattice .. instantiation "fun" :: (type, uminus) uminus begin definition fun_Compl_def: "- A = (\x. - A x)" lemma uminus_apply [simp, code]: "(- A) x = - (A x)" by (simp add: fun_Compl_def) instance .. end instantiation "fun" :: (type, minus) minus begin definition fun_diff_def: "A - B = (\x. A x - B x)" lemma minus_apply [simp, code]: "(A - B) x = A x - B x" by (simp add: fun_diff_def) instance .. end instance "fun" :: (type, boolean_algebra) boolean_algebra by standard (rule ext, simp_all add: inf_compl_bot sup_compl_top diff_eq)+ subsection \Lattice on unary and binary predicates\ lemma inf1I: "A x \ B x \ (A \ B) x" by (simp add: inf_fun_def) lemma inf2I: "A x y \ B x y \ (A \ B) x y" by (simp add: inf_fun_def) lemma inf1E: "(A \ B) x \ (A x \ B x \ P) \ P" by (simp add: inf_fun_def) lemma inf2E: "(A \ B) x y \ (A x y \ B x y \ P) \ P" by (simp add: inf_fun_def) lemma inf1D1: "(A \ B) x \ A x" by (rule inf1E) lemma inf2D1: "(A \ B) x y \ A x y" by (rule inf2E) lemma inf1D2: "(A \ B) x \ B x" by (rule inf1E) lemma inf2D2: "(A \ B) x y \ B x y" by (rule inf2E) lemma sup1I1: "A x \ (A \ B) x" by (simp add: sup_fun_def) lemma sup2I1: "A x y \ (A \ B) x y" by (simp add: sup_fun_def) lemma sup1I2: "B x \ (A \ B) x" by (simp add: sup_fun_def) lemma sup2I2: "B x y \ (A \ B) x y" by (simp add: sup_fun_def) lemma sup1E: "(A \ B) x \ (A x \ P) \ (B x \ P) \ P" by (simp add: sup_fun_def) iprover lemma sup2E: "(A \ B) x y \ (A x y \ P) \ (B x y \ P) \ P" by (simp add: sup_fun_def) iprover text \ \<^medskip> Classical introduction rule: no commitment to \A\ vs \B\.\ lemma sup1CI: "(\ B x \ A x) \ (A \ B) x" by (auto simp add: sup_fun_def) lemma sup2CI: "(\ B x y \ A x y) \ (A \ B) x y" by (auto simp add: sup_fun_def) end