src/HOL/HOLCF/Up.thy
changeset 67312 0d25e02759b7
parent 63040 eb4ddd18d635
child 67399 eab6ce8368fa
--- a/src/HOL/HOLCF/Up.thy	Mon Jan 01 21:17:28 2018 +0100
+++ b/src/HOL/HOLCF/Up.thy	Mon Jan 01 23:07:24 2018 +0100
@@ -6,40 +6,47 @@
 section \<open>The type of lifted values\<close>
 
 theory Up
-imports Cfun
+  imports Cfun
 begin
 
 default_sort cpo
 
+
 subsection \<open>Definition of new type for lifting\<close>
 
 datatype 'a u  ("(_\<^sub>\<bottom>)" [1000] 999) = Ibottom | Iup 'a
 
-primrec Ifup :: "('a \<rightarrow> 'b::pcpo) \<Rightarrow> 'a u \<Rightarrow> 'b" where
+primrec Ifup :: "('a \<rightarrow> 'b::pcpo) \<Rightarrow> 'a u \<Rightarrow> 'b"
+  where
     "Ifup f Ibottom = \<bottom>"
- |  "Ifup f (Iup x) = f\<cdot>x"
+  | "Ifup f (Iup x) = f\<cdot>x"
+
 
 subsection \<open>Ordering on lifted cpo\<close>
 
 instantiation u :: (cpo) below
 begin
 
-definition
-  below_up_def:
-    "(op \<sqsubseteq>) \<equiv> (\<lambda>x y. case x of Ibottom \<Rightarrow> True | Iup a \<Rightarrow>
-      (case y of Ibottom \<Rightarrow> False | Iup b \<Rightarrow> a \<sqsubseteq> b))"
+definition below_up_def:
+  "(op \<sqsubseteq>) \<equiv>
+    (\<lambda>x y.
+      (case x of
+        Ibottom \<Rightarrow> True
+      | Iup a \<Rightarrow> (case y of Ibottom \<Rightarrow> False | Iup b \<Rightarrow> a \<sqsubseteq> b)))"
 
 instance ..
+
 end
 
 lemma minimal_up [iff]: "Ibottom \<sqsubseteq> z"
-by (simp add: below_up_def)
+  by (simp add: below_up_def)
 
 lemma not_Iup_below [iff]: "Iup x \<notsqsubseteq> Ibottom"
-by (simp add: below_up_def)
+  by (simp add: below_up_def)
 
 lemma Iup_below [iff]: "(Iup x \<sqsubseteq> Iup y) = (x \<sqsubseteq> y)"
-by (simp add: below_up_def)
+  by (simp add: below_up_def)
+
 
 subsection \<open>Lifted cpo is a partial order\<close>
 
@@ -47,28 +54,28 @@
 proof
   fix x :: "'a u"
   show "x \<sqsubseteq> x"
-    unfolding below_up_def by (simp split: u.split)
+    by (simp add: below_up_def split: u.split)
 next
   fix x y :: "'a u"
-  assume "x \<sqsubseteq> y" "y \<sqsubseteq> x" thus "x = y"
-    unfolding below_up_def
-    by (auto split: u.split_asm intro: below_antisym)
+  assume "x \<sqsubseteq> y" "y \<sqsubseteq> x"
+  then show "x = y"
+    by (auto simp: below_up_def split: u.split_asm intro: below_antisym)
 next
   fix x y z :: "'a u"
-  assume "x \<sqsubseteq> y" "y \<sqsubseteq> z" thus "x \<sqsubseteq> z"
-    unfolding below_up_def
-    by (auto split: u.split_asm intro: below_trans)
+  assume "x \<sqsubseteq> y" "y \<sqsubseteq> z"
+  then show "x \<sqsubseteq> z"
+    by (auto simp: below_up_def split: u.split_asm intro: below_trans)
 qed
 
+
 subsection \<open>Lifted cpo is a cpo\<close>
 
-lemma is_lub_Iup:
-  "range S <<| x \<Longrightarrow> range (\<lambda>i. Iup (S i)) <<| Iup x"
-unfolding is_lub_def is_ub_def ball_simps
-by (auto simp add: below_up_def split: u.split)
+lemma is_lub_Iup: "range S <<| x \<Longrightarrow> range (\<lambda>i. Iup (S i)) <<| Iup x"
+  by (auto simp: is_lub_def is_ub_def ball_simps below_up_def split: u.split)
 
 lemma up_chain_lemma:
-  assumes Y: "chain Y" obtains "\<forall>i. Y i = Ibottom"
+  assumes Y: "chain Y"
+  obtains "\<forall>i. Y i = Ibottom"
   | A k where "\<forall>i. Iup (A i) = Y (i + k)" and "chain A" and "range Y <<| Iup (\<Squnion>i. A i)"
 proof (cases "\<exists>k. Y k \<noteq> Ibottom")
   case True
@@ -78,20 +85,19 @@
   proof
     fix i :: nat
     from Y le_add2 have "Y k \<sqsubseteq> Y (i + k)" by (rule chain_mono)
-    with k have "Y (i + k) \<noteq> Ibottom" by (cases "Y k", auto)
-    thus "Iup (A i) = Y (i + k)"
+    with k have "Y (i + k) \<noteq> Ibottom" by (cases "Y k") auto
+    then show "Iup (A i) = Y (i + k)"
       by (cases "Y (i + k)", simp_all add: A_def)
   qed
   from Y have chain_A: "chain A"
-    unfolding chain_def Iup_below [symmetric]
-    by (simp add: Iup_A)
-  hence "range A <<| (\<Squnion>i. A i)"
+    by (simp add: chain_def Iup_below [symmetric] Iup_A)
+  then have "range A <<| (\<Squnion>i. A i)"
     by (rule cpo_lubI)
-  hence "range (\<lambda>i. Iup (A i)) <<| Iup (\<Squnion>i. A i)"
+  then have "range (\<lambda>i. Iup (A i)) <<| Iup (\<Squnion>i. A i)"
     by (rule is_lub_Iup)
-  hence "range (\<lambda>i. Y (i + k)) <<| Iup (\<Squnion>i. A i)"
+  then have "range (\<lambda>i. Y (i + k)) <<| Iup (\<Squnion>i. A i)"
     by (simp only: Iup_A)
-  hence "range (\<lambda>i. Y i) <<| Iup (\<Squnion>i. A i)"
+  then have "range (\<lambda>i. Y i) <<| Iup (\<Squnion>i. A i)"
     by (simp only: is_lub_range_shift [OF Y])
   with Iup_A chain_A show ?thesis ..
 next
@@ -104,59 +110,62 @@
 proof
   fix S :: "nat \<Rightarrow> 'a u"
   assume S: "chain S"
-  thus "\<exists>x. range (\<lambda>i. S i) <<| x"
+  then show "\<exists>x. range (\<lambda>i. S i) <<| x"
   proof (rule up_chain_lemma)
     assume "\<forall>i. S i = Ibottom"
-    hence "range (\<lambda>i. S i) <<| Ibottom"
+    then have "range (\<lambda>i. S i) <<| Ibottom"
       by (simp add: is_lub_const)
-    thus ?thesis ..
+    then show ?thesis ..
   next
     fix A :: "nat \<Rightarrow> 'a"
     assume "range S <<| Iup (\<Squnion>i. A i)"
-    thus ?thesis ..
+    then show ?thesis ..
   qed
 qed
 
+
 subsection \<open>Lifted cpo is pointed\<close>
 
 instance u :: (cpo) pcpo
-by intro_classes fast
+  by intro_classes fast
 
 text \<open>for compatibility with old HOLCF-Version\<close>
 lemma inst_up_pcpo: "\<bottom> = Ibottom"
-by (rule minimal_up [THEN bottomI, symmetric])
+  by (rule minimal_up [THEN bottomI, symmetric])
+
 
 subsection \<open>Continuity of \emph{Iup} and \emph{Ifup}\<close>
 
 text \<open>continuity for @{term Iup}\<close>
 
 lemma cont_Iup: "cont Iup"
-apply (rule contI)
-apply (rule is_lub_Iup)
-apply (erule cpo_lubI)
-done
+  apply (rule contI)
+  apply (rule is_lub_Iup)
+  apply (erule cpo_lubI)
+  done
 
 text \<open>continuity for @{term Ifup}\<close>
 
 lemma cont_Ifup1: "cont (\<lambda>f. Ifup f x)"
-by (induct x, simp_all)
+  by (induct x) simp_all
 
 lemma monofun_Ifup2: "monofun (\<lambda>x. Ifup f x)"
-apply (rule monofunI)
-apply (case_tac x, simp)
-apply (case_tac y, simp)
-apply (simp add: monofun_cfun_arg)
-done
+  apply (rule monofunI)
+  apply (case_tac x, simp)
+  apply (case_tac y, simp)
+  apply (simp add: monofun_cfun_arg)
+  done
 
 lemma cont_Ifup2: "cont (\<lambda>x. Ifup f x)"
 proof (rule contI2)
-  fix Y assume Y: "chain Y" and Y': "chain (\<lambda>i. Ifup f (Y i))"
+  fix Y
+  assume Y: "chain Y" and Y': "chain (\<lambda>i. Ifup f (Y i))"
   from Y show "Ifup f (\<Squnion>i. Y i) \<sqsubseteq> (\<Squnion>i. Ifup f (Y i))"
   proof (rule up_chain_lemma)
     fix A and k
     assume A: "\<forall>i. Iup (A i) = Y (i + k)"
     assume "chain A" and "range Y <<| Iup (\<Squnion>i. A i)"
-    hence "Ifup f (\<Squnion>i. Y i) = (\<Squnion>i. Ifup f (Iup (A i)))"
+    then have "Ifup f (\<Squnion>i. Y i) = (\<Squnion>i. Ifup f (Iup (A i)))"
       by (simp add: lub_eqI contlub_cfun_arg)
     also have "\<dots> = (\<Squnion>i. Ifup f (Y (i + k)))"
       by (simp add: A)
@@ -166,96 +175,86 @@
   qed simp
 qed (rule monofun_Ifup2)
 
+
 subsection \<open>Continuous versions of constants\<close>
 
-definition
-  up  :: "'a \<rightarrow> 'a u" where
-  "up = (\<Lambda> x. Iup x)"
+definition up  :: "'a \<rightarrow> 'a u"
+  where "up = (\<Lambda> x. Iup x)"
 
-definition
-  fup :: "('a \<rightarrow> 'b::pcpo) \<rightarrow> 'a u \<rightarrow> 'b" where
-  "fup = (\<Lambda> f p. Ifup f p)"
+definition fup :: "('a \<rightarrow> 'b::pcpo) \<rightarrow> 'a u \<rightarrow> 'b"
+  where "fup = (\<Lambda> f p. Ifup f p)"
 
 translations
-  "case l of XCONST up\<cdot>x \<Rightarrow> t" == "CONST fup\<cdot>(\<Lambda> x. t)\<cdot>l"
-  "case l of (XCONST up :: 'a)\<cdot>x \<Rightarrow> t" => "CONST fup\<cdot>(\<Lambda> x. t)\<cdot>l"
-  "\<Lambda>(XCONST up\<cdot>x). t" == "CONST fup\<cdot>(\<Lambda> x. t)"
+  "case l of XCONST up\<cdot>x \<Rightarrow> t" \<rightleftharpoons> "CONST fup\<cdot>(\<Lambda> x. t)\<cdot>l"
+  "case l of (XCONST up :: 'a)\<cdot>x \<Rightarrow> t" \<rightharpoonup> "CONST fup\<cdot>(\<Lambda> x. t)\<cdot>l"
+  "\<Lambda>(XCONST up\<cdot>x). t" \<rightleftharpoons> "CONST fup\<cdot>(\<Lambda> x. t)"
 
 text \<open>continuous versions of lemmas for @{typ "('a)u"}\<close>
 
 lemma Exh_Up: "z = \<bottom> \<or> (\<exists>x. z = up\<cdot>x)"
-apply (induct z)
-apply (simp add: inst_up_pcpo)
-apply (simp add: up_def cont_Iup)
-done
+  by (induct z) (simp add: inst_up_pcpo, simp add: up_def cont_Iup)
 
 lemma up_eq [simp]: "(up\<cdot>x = up\<cdot>y) = (x = y)"
-by (simp add: up_def cont_Iup)
+  by (simp add: up_def cont_Iup)
 
 lemma up_inject: "up\<cdot>x = up\<cdot>y \<Longrightarrow> x = y"
-by simp
+  by simp
 
 lemma up_defined [simp]: "up\<cdot>x \<noteq> \<bottom>"
-by (simp add: up_def cont_Iup inst_up_pcpo)
+  by (simp add: up_def cont_Iup inst_up_pcpo)
 
 lemma not_up_less_UU: "up\<cdot>x \<notsqsubseteq> \<bottom>"
-by simp (* FIXME: remove? *)
+  by simp (* FIXME: remove? *)
 
 lemma up_below [simp]: "up\<cdot>x \<sqsubseteq> up\<cdot>y \<longleftrightarrow> x \<sqsubseteq> y"
-by (simp add: up_def cont_Iup)
+  by (simp add: up_def cont_Iup)
 
-lemma upE [case_names bottom up, cases type: u]:
-  "\<lbrakk>p = \<bottom> \<Longrightarrow> Q; \<And>x. p = up\<cdot>x \<Longrightarrow> Q\<rbrakk> \<Longrightarrow> Q"
-apply (cases p)
-apply (simp add: inst_up_pcpo)
-apply (simp add: up_def cont_Iup)
-done
+lemma upE [case_names bottom up, cases type: u]: "\<lbrakk>p = \<bottom> \<Longrightarrow> Q; \<And>x. p = up\<cdot>x \<Longrightarrow> Q\<rbrakk> \<Longrightarrow> Q"
+  by (cases p) (simp add: inst_up_pcpo, simp add: up_def cont_Iup)
 
-lemma up_induct [case_names bottom up, induct type: u]:
-  "\<lbrakk>P \<bottom>; \<And>x. P (up\<cdot>x)\<rbrakk> \<Longrightarrow> P x"
-by (cases x, simp_all)
+lemma up_induct [case_names bottom up, induct type: u]: "P \<bottom> \<Longrightarrow> (\<And>x. P (up\<cdot>x)) \<Longrightarrow> P x"
+  by (cases x) simp_all
 
 text \<open>lifting preserves chain-finiteness\<close>
 
 lemma up_chain_cases:
-  assumes Y: "chain Y" obtains "\<forall>i. Y i = \<bottom>"
+  assumes Y: "chain Y"
+  obtains "\<forall>i. Y i = \<bottom>"
   | A k where "\<forall>i. up\<cdot>(A i) = Y (i + k)" and "chain A" and "(\<Squnion>i. Y i) = up\<cdot>(\<Squnion>i. A i)"
-apply (rule up_chain_lemma [OF Y])
-apply (simp_all add: inst_up_pcpo up_def cont_Iup lub_eqI)
-done
+  by (rule up_chain_lemma [OF Y]) (simp_all add: inst_up_pcpo up_def cont_Iup lub_eqI)
 
 lemma compact_up: "compact x \<Longrightarrow> compact (up\<cdot>x)"
-apply (rule compactI2)
-apply (erule up_chain_cases)
-apply simp
-apply (drule (1) compactD2, simp)
-apply (erule exE)
-apply (drule_tac f="up" and x="x" in monofun_cfun_arg)
-apply (simp, erule exI)
-done
+  apply (rule compactI2)
+  apply (erule up_chain_cases)
+   apply simp
+  apply (drule (1) compactD2, simp)
+  apply (erule exE)
+  apply (drule_tac f="up" and x="x" in monofun_cfun_arg)
+  apply (simp, erule exI)
+  done
 
 lemma compact_upD: "compact (up\<cdot>x) \<Longrightarrow> compact x"
-unfolding compact_def
-by (drule adm_subst [OF cont_Rep_cfun2 [where f=up]], simp)
+  unfolding compact_def
+  by (drule adm_subst [OF cont_Rep_cfun2 [where f=up]], simp)
 
 lemma compact_up_iff [simp]: "compact (up\<cdot>x) = compact x"
-by (safe elim!: compact_up compact_upD)
+  by (safe elim!: compact_up compact_upD)
 
 instance u :: (chfin) chfin
-apply intro_classes
-apply (erule compact_imp_max_in_chain)
-apply (rule_tac p="\<Squnion>i. Y i" in upE, simp_all)
-done
+  apply intro_classes
+  apply (erule compact_imp_max_in_chain)
+  apply (rule_tac p="\<Squnion>i. Y i" in upE, simp_all)
+  done
 
 text \<open>properties of fup\<close>
 
 lemma fup1 [simp]: "fup\<cdot>f\<cdot>\<bottom> = \<bottom>"
-by (simp add: fup_def cont_Ifup1 cont_Ifup2 inst_up_pcpo cont2cont_LAM)
+  by (simp add: fup_def cont_Ifup1 cont_Ifup2 inst_up_pcpo cont2cont_LAM)
 
 lemma fup2 [simp]: "fup\<cdot>f\<cdot>(up\<cdot>x) = f\<cdot>x"
-by (simp add: up_def fup_def cont_Iup cont_Ifup1 cont_Ifup2 cont2cont_LAM)
+  by (simp add: up_def fup_def cont_Iup cont_Ifup1 cont_Ifup2 cont2cont_LAM)
 
 lemma fup3 [simp]: "fup\<cdot>up\<cdot>x = x"
-by (cases x, simp_all)
+  by (cases x) simp_all
 
 end